Ike Prelim Radar Analysis

Now that power has finally been restored to my house, I have had the opportunity to download all of the raw level2 radar data from the hurricane. After driving around for only about 10 min and looking at the damage left by the storm, I started to notice some interesting patterns in the damage. You would see streets where most of the homes received light to moderate roof damage right next to other streets that received little to no roof damage. As was the case on my street, this pattern was played out on a more local level, where my neighbors house had significant roof damage while I managed to only lose a couple of shingles.

This type of pattern suggested that there were likley strong localized downburst events within the western eye wall which was characterized by unusually deep convection while it moved across the central and western sections of the Houston metro areas. Below are some prelim findings from analyzing some of the 88D radar data.

The screen shots below illustrate the local wind maxima (brighter blue streaks in the base velocity data) which occured throughout the western sections of Ike.

Post Ike

Well, it looks like this was not another Rita as most of the region remains without power and is still cleaning up the mess left behind by the first "major" hurricane to hit the Houston/Galveston area in 25 years. Once my house gets electricity back, I will begin an extensive post storm research project and will post any interesting results I find. 

Rita Repeat?

This is a link to the RITA Graphics Archive.  The way Ike's track is moving looks very similar to what Rita did in 2005. 

http://www.nhc.noaa.gov/archive/2005/RITA_graphics.shtml

This is the archive of the Ike Graphics

Ike_Graphics

The tracks do differ slightly.  I don't believe Ike will make it as far as Louisiana, but it may continue to put farther up the coast.

Hurricane Ike - Intensity Discussion - 9am Wednesday

Ike continues to look better and better on the latest IR satellite imagery this morning. The NOAA plane had an extrapolated pressure of 955 mb when it made a pass through the center at 13Z. Even though the pressures are down, we continue to wait for the winds to catch up. Ambient pressures throughout the outer portions of the storm are also rather low, therefore not creating a very tight pressure gradient as of yet, which maybe one of the reasons why we haven't see a substantial increase in the winds yet; however as convection continues to increase around the center of circulation, we should see the pressures rise and wind speeds in the outer bands come down and that will allow for the storm to really start to pick up steam.

It also looks like Ike will pass over some very warm loop currents in the southern gulf as he moves off to the northwest or west-northwest over the next 24 hours or so, which also favors significant strengthening.

It will be interesting to see what the winds are during the 10am update, although we might not really start to see Ike take off until this evening.

12z Model Update - Hurricane Ike

The models which were south of Corpus look to have shifted back north towards the rest of the model guidance with the UKMET model still north of Matagorda Bay. We won't be able to take a look at the 12z ECMWF until noon or so, but unless Ike makes an unexpected change in its current track, then I would not expect to see much change when compared to the 00z (Which I analyzed in my previous post).

I will continue to keep the forecast track I made yesterday which brings the center of Ike onshore through or just north of Matagorda Bay. I would expect to not see much change in the current NHC track at the 10am update; however a slight shift north is possible, given the latest model runs and slower forward speed of Ike seen over the past couple of hours.

12z Models
http://www.wunderground.com/tropical/tracking/at200809_model.html

Ike Update - 8am Wednesday

The latest update on Ike as of 8am has the storm still at category 1 strength moving northwest at 8mph. The latest satellite imagery shows lots of central dense overcast around the center which would tend to suggest that Ike is getting ready to really start to strengthen. Right now Ike is currently forecast by the NHC to make landfall along the middle or upper Texas coast as a major cat 3 or cat 4 hurricane late Friday or early Saturday morning.

Below is a summary of a convo I had last night with a good friend and 30 year seasoned tropical forecaster here in Houston...

I am concerned that county officials are not taking this storm seriously. We are looking at a setup almost identical to Rita in 2005 and there does not seem to be much concern. Rita was forecast to hit on Saturday morning like Ike, but on the Wednesday before Rita was to hit near or just south of Matagorda Bay, we were already in full evacuation.

Mean while the people near the TX/LA border were thankful that the storm was forecast to hit well down the coast from them.

Ike is very likely going to be a Cat 3-4 when it hits the mid (or upper) Texas coast early Saturday morning. It's size means that squalls will begin impacting the upper to middle coast Friday morning. That leaves only today and tomorrow for evacuations. I can tell you this, if Ike deviates from the forecast track then it's far more likely to move inland north of the current projection than south. And only a TINY shift in timing of the turn, and a shift to the east side of Matagorda Bay, will mean a potential catastrophe here in the Houston-Galveston area.

If I lived in a surge zone near Galveston Bay I'd be prepared to leave and I'd get out before the hasty evacuation is called for tomorrow. Maybe we'll get lucky and NOW the forecast track is perfect. Yeah, maybe. But if the forecast is wrong, then we are looking at a very serious situation.
Again, we won't know for sure Ike isn't going to make a direct hit on Freeport/Galveston until during the day on Friday. We won't know today, we won't really know for sure tomorrow either.

I sure hope the current forecast is dead on, but I fear it isn't. Statistics over the past 10 years (from a study by Lance Wood at the Houston/Galveston NWS) show that 74% of the time, in the Gulf, the hurricanes track right of the forecast track.

Ok, back to the data...

The 00z models continue to be in good agreement in a landfall just south of Matagorda Bay, somewhere between Corpus and Rockport; however the ECMWF has actually shifted up to just north of Matagorda Bay. This would be a good model to watch as it has an excellent track history of being able to capture the long term synoptic scale motions and I would put a good bit of weight behind this model...something that the NHC has been doing recently.

What is concerning is that Ike is currently moving a couple hours slower than the forecast track...something that will be needed in order to see that northerly turn prior to landfall. If this trend continues then we could see models possibly try and shift further up the coast. Again, it is still a bit early to really boost confidence in any one scenario, but this will be a trend worth watching.

Early 00z Guidance - Hurricane Ike

Below is some very early 00z numerical guidance....look for another update around 10pm once all the models complete there runs.

Major Hurricane Ike - Possible NW Gulf Threat

Once again, it looks like the northwestern Gulf could potentially be threatened by yet another potentially major hurricane towards the end of the week. Since yesterday all of the model guidance along with the official NHC track has shifted westward (towards the Texas coast) as it looks like Ike will not be impacted by the eastern US trough left in the wake of Hanna.

The main player which will determine Ike's eventual movement and landfall location will be a developing west coast trough which is forecast by models to eject eastward across the US by mid-week. The hope for us was that this trough would eject a bit faster and deeper and therefore turn Ike off to the north sooner, taking the system off to our east. However, the last day and a half of model runs suggest that this feature might not have any impact on Ike's movement at all since it looks like it could remain too far to the north and rather weak. Now it is important to note, that there could be additional significant changes in Ike's track depending upon how he interacts with Cuba over the next 24-36 hours.

The intensity forecast remains the most uncertain, especially since it is getting ready to move over Cuba and will undergo some significant weakening on the current NHC forecast track. The storm is expected to emerge out in the southeast Gulf Tuesday evening and slowly regain major Hurricane status by 2pm Friday. Therefore, all southeast Texas residents need to review their hurricane preparation plans and get ready to take action later on in the week, should there be little change to the current forecast track.

Below is an upate from the pro Met here in Houston and a look at the latest Track and IR Sat imagery.

Update from Pro Met Jeff Linder
Large and dangerous hurricane forecast in the NW Gulf of Mexico the end of this week. State of Texas began their 120 hour count down for impact of a major hurricane on the TX coast today at 1100am. H-72: 1100am Tuesday H-36: 1100pm Wednesday H-0: 1100am Friday Full activation of the State Operations Center at 800am Monday. Large scale evacuations along the entire TX coast and full scale contra-flow operations will be possible this week given the current NHC forecast track. TX residents need to review their hurricane preparation plans and be fully ready to enact these plans this week. Residents in coastal storm surge evacuation zones need to review evacuation routes and be fully ready to leave this week if ordered to do so. Ike Update: Powerful hurricane bearing down on eastern Cuba. Recon. suggest double wind maximum suggesting Ike is undergoing an eyewall replacement cycle. There is not enough time for Ike to complete this cycle before is crosses the Cuban coast. Track: Nearly all global models except for the HWRF suggest the NW Gulf of Mexico will now be threatened by Ike. There is just not enough of a weakness... to turn the hurricane to our east...and it will round the southern side of the high building over the SC states and aim at the NW Gulf of Mexico. The guidance is fairly well clustered when the HWRF is tossed out and it is now fully expected that Ike will not be captured by the US E coast trough and will be a problem for TX and LA. Intensity: It appears we will be facing a major hurricane a some point in the Gulf of Mexico. The intensity is more uncertain than the track given the interaction with Cuba and what shape the inner core will be in once it emerges into the Gulf of Mexico. NHC is forecasting Ike to gradually rebuild its inner core and regain major hurricane status in the central Gulf of Mexico. Past experience has shown that once an inner core is destroyed it does take a while for it to rebuild...we shall see. Also of note...Ike will become a very large hurricane over the Gulf of Mexico likely expanding in size to nearly the entire Gulf as the interaction with Cuba broadens the wind field.

8pm NHC Forecast Track



18z Model Guidance



Latest IR Sat Imagery

Gustav Update (Redeveloping south of Jamaica)

A lot of uncertainty remains in where Gustav will ultimately make landfall along the US Gulf coast. There is still a rather big spread beyond 48 hours with several of the so called "most reliable" models taking the far eastern extreme (MS/AL coast) and others taking the far western extreme (towards Corpus Christi). Below I will try and break down the possible senarios and what the models and NHC have said recently about Gustav.

So far today the storm's center redeveloped further south from its original location which caused a slight westward shift in both the model guidance and the official NHC track; however this evening we have seen another shift back to the east some 20 miles. Models are still having a hard time grasping a hold of a well defined center of circulation and therefore continue to be all over the place as far as possible landfall locations.

It looks like we will really start to get a better handle on where Gustav might end up going by tomorrow evening once the storm has a chance to get out over open waters and strengthen. The main forecast variable that will likely end up being the deciding player in where Gustav eventually ends up going will be a large ridge of high pressure located over the southeastern US. Current thinking from the NHC has Gustav getting caught up in a mid-level weakenss over the eastern gulf which will help curve the storm more to the right, towards the central LA coastline by late Monday or early Tuesday.

Something to watch closley over the next few days is that the models slow the storm down as it approaches the central LA coastline Monday. This is because Gustav will be runing up into the southwestern edge of the southeastern US high. If the storm slows down, it is possible that it could be pushed westward along the LA coast and into Texas.

On the otherhand, other models really develop a strong weakenss in the high which intern "pulls" the storm northeast and onshore somewhere near the Mississippi/Alabama coastline.

So needless to say, it is still too early to really start to narrow down where Gustav might make landfall. I will be out of town until Monday (so un, but it will be important for everyone to make sure they exersice there Hurricance precautions this weekend as Gustav is forecast to become a major Hurricane (Cat 3+) once he gets over the very warm waters in the gulf.

On one more out of order note...it will be interesting to see how our own MM5 model does once the storm gets closer to landfall since it only goes out 3 days.

Below are the two extremes between some of the more "reliable" models.

GFDL Output (Eastern Exreme)



HRWF Output (Western Extreme)



8pm NHC Update Track

Hurricane Gustav in the Gulf Early Next Week

The quick formation and intensification of Hurricane Gustav as many people scrambling to get a handle on where he is expected to go next week as all the models and the official NHC track have him entering the gulf Saturday afternoon.

Right now the ECMWF, Canadian, and UKMET models all depict a strong area of high pressure over the southeastern US early next week which would favor a more west-northwest movement of Gustav as he trecks into the central gulf Sunday. At this time the GFS is the only model I can find which still shows a weakness in the ridge over the central to eastern gulf Sunday through Tuesday. Should the mid-upper level pattern indeed turn out to favor the ECMWF, Canadian, and UKMET, then a western gulf landfall looks quite possible; however we are still a week out so look for the forecast to change a lot. Right now we will just have to wait and watch. By Saturday afternoon, we will likely have a better handel on where Gustav might end up making landfall.

Flooding Rains Possible Through Wednesday

A very fall like weather pattern will set up across southeast Texas this week and provide not only drought busting rains, but bring the potential for flooding through at least Wednesday. The upper level synoptic pattern will consist of a slow moving north Texas cut-off area of mid to upper level low pressure which will be moving slowly down across the state through Wednesday. Very good agreement exists among the computer models in depicting increasing diffluence aloft along with increasing lift through Monday evening. Several rounds of heavy thunderstorms look likely through mid week as vort max's rotate around the upper level low and get ejected across the region.

Flooding rains are looking more and more likely as models now forecast precip-water values to be close to topping the charts (near 2.3-2.5'') over the area which will lead to excessive rain rates under the convective activity. Of concern is the fact the models don't really show the low lifting out of the region until Friday which will allow for round after round to train over the area.

At this time the HPC (Hydrometeorological Prediction Center) has the 1-5 day precip accumulations in the 4 inch range; however our local NWS would not be surprised to see those numbers increased by another 1-3 inches by tomorrow afternoon. The reason being, the extremely high precip-water values combined with the slow movement of the low.

This will be a situation that will need to be watched closley as we head through the week and flash flood watching might be issued at some point in time this week.

12z NAM- 19z Tuesday Forecast Sounding (Showing Saturated Profile)



HPC 5-Day Forecasted Precip-Accumulations


GFS Monday Precip-Water Forecast



GFS Precip Accumulations through Wednesday

2 tropical systems in the models

ECMWF takes the current tropical wave east of Cuba and strengthens it into a tropical storm to hit the tip of Florida in 168hr, intensifies over land (?) and continues across and hits the panhandle of Florida as hurricane around hour 216. Model agreement is medium for the GFS does not capture the system, however the CMC takes it into the Atlantic and away from the Gulf.

There is a tropical wave currently off of Africa and the GFS takes the system into the Gulf of Mexico as a very strong hurricane. HOWEVER, this forecast is 324 hours out and the GFS is not always reliable. We will have to watch the other models when they are available for those forecast hours, and monitor this system.

Just thought you guys would like to know!

- Monica

Locally Heavy Rainfall Possible Late Monday/Tuesday

The latest models continue to point towards a rather significant pattern chance across southeast Texas over the next 24-48 hours as a slow moving frontal boundary up across north Texas and associated mid level low move southeast. The 00z model run of the NAM and GFS still show some type of mesoscale convective system working its way southeast out of north/central Texas Monday night and into the northern sections of southeast Texas Tuesday morning. The models then develop widespread convection over the majority of the region during the day as moisture levels pool ahead of the 850mb trough axis which should be slowly moving south out of north Texas.

Thunderstorms will likely be very efficient heavy rain makers as precip water values are expected to be in the 2.2-2.5'' range, which is about 2 standard deviations above the normal for this time of year. Also, we will see a slow moving weak frontal boundary acting as a focus for the shower and thunderstorm activity along with a diffluence noted in the 300-250mb winds to help add additional lift.

Now, it is not certain where the heaviest rain will fall across the area, but it looks pretty good that some people in southeast Texas could see some drought busting rain during the late Monday through Wednesday time frame.

Much Needed Rainfall from Edouard

Even though the center of circulation from tropical storm Edouard moved inland well to the east of where it was first forecast to make landfall, he still managed to produce some drought relieving rainfall across central and eastern sections of southeast Texas Tuesday. As a matter of fact, KIAH set a record for the date picking up 2.81'' which broke the old record of 2.65'' set back in 1994. A complete list of rainfall totals from around the region can be found below, along with the KHGX radar estimated storm total precip.

One item to note is that the Moody Tower H-Net site seems to be over estimating rainfall as it reported a little bit over 6'' from Edouard, while other official and non-official sites recorded rainfall in the 2-3 inch range. I archived the raw radar data files from KHGX for the entire event and will be going back over the data to see if it could have been a very small scale event; however I do not suspect that it was. Nicole and I will be running a calibration test on the gauge sometime over the next week or so and will post out findings. The other H-Net sites with the exception of UHCC (which we already know that is broken) gathered what looks to be very accurate rainfall data...matching up nicely with surrounding gauges and radar estimates.

Rainfall Data from Around Southeast Texas

HARRIS COUNTY -
BAYTOWN: BAYTOWN EOC..........................6.48 IN
SHELDON: SAN JACINTO RIVER AT BANANA BEND.....5.91 IN
PASADENA: BIG ISLAND SLOUGH AT FAIRMONT PKWY..5.75 IN
BAYTOWN: CEDAR BAYOU AT SH 146................5.27 IN
BAYTOWN: GOOSE CREEK AT SH 146................5.08 IN
BAYTOWN: GOOSE CREEK AT BAKER ROAD............3.51 IN
PASADENA: WILLOW SPRING AT FAIRMONT PARKWAY...5.08 IN
SHOREACRES: TAYLOR BAYOU AT SHOREACRES BLVD...4.73 IN
LA PORTE: LITTLE CEDAR BAYOU AT 8TH ST........4.49 IN
SHELDON: CARPENTERS BAYOU AT US HWY 90........4.49 IN
WALLISVILLE: CARPENTERS BAYOU AT WALLISVILLE..4.41 IN
E HOUSTON: I-10 AT NORMANDY...................4.41 IN
SAN JACINTO RIVER AT I-10 EAST................4.37 IN
HOUSTON: HOUSTON TRANSTAR.....................4.02 IN
FRED HARTMAN BRIDGE...........................4.01 IN
NE HOUSTON: GREENS BAYOU AT LEY ROAD..........3.90 IN
NE HOUSTON: GREENS BAYOU AT TIDWELL...........3.78 IN
NE HOUSTON: GREENS BAYOU AT MT HOUSTON PKWY...3.46 IN
SE HOUSTON: I-610 AT SHIP CHANNEL.............3.38 IN
PASADENA: BERRY BAYOU AT FOREST OAKS..........3.27 IN
NW HOUSTON: VOGEL CREEK AT VICTORY............3.19 IN
HOUSTON: BUFFALO BAYOU AT TURNING BASIN.......2.92 IN
WHITE OAK BAYOU AT FAIRBANKS-N HOUSTON........2.91 IN
HOUSTON: LITTLE WHITE OAK BAYOU AT TRIMBLE....2.88 IN
HOUSTON INTERCONTINENTAL AIRPORT..............2.76 IN
ALDINE: GREENS BAYOU AT KNOBCREST.............2.68 IN
SPRING: CYPRESS LATERAL AT FM 1960............2.64 IN
SE HOUSTON: BEAMER DITCH AT HUGHES ROAD.......2.44 IN
SPRING: CYPRESS CREEK AT I-45.................2.41 IN
HOUSTON: RELIANT PARK.........................2.16 IN
MEDICAL CENTER: METRO RAIL AT FANNIN..........2.01 IN
HOUSTON HOBBY AIRPORT.........................1.99 IN
TOMBALL: HOOKS AIRPORT........................1.80 IN
W HOUSTON: BUFFALO BAYOU AT DAIRY ASHFORD.....1.77 IN
JERSEY VILLAGE: LANGHAM CREEK/W LITTLE YORK...1.77 IN
MISSION BEND: BRAYS BAYOU AT SH 6.............1.18 IN
KATY: BUFFALO BAYOU AT US HWY 90..............0.55 IN

GALVESTON COUNTY -
KEMAH: SH 146.................................2.67 IN
LEAGUE CITY: CLEAR CREEK AT I-45..............2.01 IN
GALVESTON CAUSEWAY............................1.11 IN
BOLIVAR AT LOOP 108...........................0.86 IN
GALVESTON: SCHOLES FIELD......................0.58 IN

KHGX Storm Total Precip Graphic

2pm Harris County Rainfall

Note: Ignore the 43+ inch totals that several of the gauges are reporting, that is an error.

Edouard Inland, Heavy Rain Possible

Tropical storm Edouard has moved inland this morning across Chambers county and based on the latest radar imagery looks to be located around the Anahuac area moving off to the west-northwest around 15mph. So far the main impacts have been the rain with doppler radar estimating a swath of 2-5 inches has fallen across central/eastern Harris, northern Galveston, and most of Chambers counties this morning. Moderate to heavy rain continues to wrap around the circulation on Edouard across most of metro Houston and this trend should continue through the early afternoon. A break in the heavier rain may occur later this afternoon before additional convection will be possible this evening as the eastern side of the storm arrives. Currently the KHGX radar shows some very deep thunderstorm activity occurring over the gulf moving towards southeast Texas where wind gusts to 60mph have been measured.

As far as the winds are concerned, with the shift in track, Houston and most of the H-Net sites have seen winds in the 20-30mph range with higher gusts, especially down at UHCC and UHWL. Look for winds to continue out of the north and northwest for the next several hours, before swinging around to the south and increasing as the circulation moves off to the northwest of the metro area.

Latest Radar with NHC Track

10pm NHC Edouard Track Map

Latest track with the official NHC track overlaid. It is interesting to note the increase in convection around the storm. When I put the storm into motion, it actually looks like the center might be a bit south of where the NHC currently has it...maybe just my eyes playing tricks on me though.

Storm Update 10pm - Edouard Turns West-Northwest

Kind of a big update from the NHC with the center of Edouard redeveloping close to the new flare up of convection, slightly north of the previous center of circulation. This has caused the latest forecast track to be shifted up the coastline with the storm's center now expected to cross the coast around High Island, a good shift east from the 7pm position.

This will be something to watch closely to see if a further shift up the coast occurs through the night. If this trend were to continue, we would likely see much less of an impact here in Houston since the storm remains rather small and unorganized with all of the convection on the north and east side of the system. Also note that the advisory has no 60 mph wind west of the center at landfall, only in the NE quadrant in the heavy squalls. Barely TS wind in SW-NW part of storm, if that. So, it is possible that Houston might only see an inch or two of rain as Edouard moves inland and we will have to wait until his circulation moves northwest of the city in order to see some feeder bands set up and possibly give us some more substantial rainfall. Again, this is assuming the storm doesn't start to produce more significant convection around the western side of the circulation. The latest radar and satellite imagery does show a flare up of storms on the northern side which is trying to wrap around to the west.

Here is the latest public advisory from the NHC and I will post the latest Hurricane Local Statement from the National Weather Service when it becomes available around 11pm.

TROPICAL STORM EDOUARD ADVISORY NUMBER   7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL052008
1000 PM CDT MON AUG 04 2008

...EDOUARD STRENGTHENS AND TURNS WEST-NORTHWESTWARD...

AT 10 PM CDT...0300 UTC...THE TROPICAL STORM WARNING IS DISCONTINUED
EAST OF GRAND ISLE LOUISIANA.

A TROPICAL STORM WARNING REMAINS IN EFFECT FROM GRAND ISLE WESTWARD
TO PORT O'CONNOR TEXAS.

A HURRICANE WATCH REMAINS IN EFFECT FROM WEST OF INTRACOASTAL CITY
LOUISIANA TO PORT O'CONNOR.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 1000 PM CDT...0300Z...THE CENTER OF TROPICAL STORM EDOUARD WAS
LOCATED NEAR LATITUDE 28.7 NORTH...LONGITUDE 92.2 WEST OR ABOUT 105
MILES...170 KM...SOUTH OF LAFAYETTE LOUISIANA AND ABOUT 160 MILES...
260 KM...EAST-SOUTHEAST OF GALVESTON TEXAS.

EDOUARD IS MOVING TOWARD THE WEST-NORTHWEST NEAR 8 MPH...13 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE WITH SOME INCREASE
IN FORWARD SPEED DURING THE NEXT COUPLE OF DAYS.  ON THE FORECAST
TRACK...THE CENTER OF EDOUARD IS EXPECTED TO BE NEAR OR OVER THE
UPPER TEXAS OR SOUTHWESTERN LOUISIANA COASTS BY MIDDAY TUESDAY.

REPORTS FROM COASTAL DOPPLER RADARS INDICATE THAT MAXIMUM SUSTAINED
WINDS HAVE INCREASED TO NEAR 60 MPH...95 KM/HR...WITH HIGHER GUSTS.
EDOUARD IS FORECAST TO STRENGTHEN...AND IT IS EXPECTED TO BE NEAR
HURRICANE STRENGTH BY THE TIME IT REACHES THE COASTLINE DURING
THE DAY TOMORROW.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER.  SEVERAL ELEVATED OIL RIGS SOUTH OF THE LOUISIANA
COAST HAVE BEEN REPORTING SUSTAINED WINDS OF 45 TO 55 MPH DURING
THE PAST FEW HOURS.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB...29.50 INCHES.

A STORM SURGE OF 2 TO 4 FT ABOVE NORMAL TIDE LEVELS CAN BE EXPECTED
IN THE WARNING AREA IN AREAS OF ONSHORE WINDS.

EDOUARD IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 3 TO 5
INCHES IN SOME LOUISIANA COASTAL PARISHES.  ACCUMULATIONS OF 4 TO 6
INCHES...WITH ISOLATED MAXIMUM AMOUNTS OF 10 INCHES ARE POSSIBLE
OVER SOUTHEASTERN TEXAS.

ISOLATED TORNADOES ARE POSSIBLE OVER PORTIONS OF SOUTHERN LOUISIANA
AND THE UPPER TEXAS COAST TONIGHT AND TUESDAY.

REPEATING THE 1000 PM CDT POSITION...28.7 N...92.2 W.  MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 8 MPH.  MAXIMUM SUSTAINED WINDS...60
MPH.  MINIMUM CENTRAL PRESSURE...999 MB.

10pm NHC Track

Tropical Storm Edouard 7pm Update

Edouard continues to get better organized this afternoon with new convection developing around the low level circulation. There has been some misconceptions this afternoon that the storm is taking a "jog" to the north but it looks like its the rain bands moving north which is giving the illusion that the storm is moving north. This will be something that I will be watching however there have been no indications that this is occurring.

The latest GOES-East Shear Analysis shows little to no shear over and ahead of the system, along with very warm sea surface temperatures which favor a strengthening system; however since Edouard remains close to land, he has been pulling in some of the dry continental air at the mid-levels which could be one of the reasons why we haven't see a significant increase in strength yet. The continued slower forward speed is something to be watched as well since this would also favor a strengthening system as it will have more time to spin over water. The latest forecast from the hurricane center has slowed the arrival of Edouard by about 4 hours with a landfall around Galveston Island by noon tomorrow possibly as a cat 1 Hurricane.

Below is a threat outline that I was given by a friend from Impact Weather who has 20 years of tropical experience here in Houston.

"I've busy forecasting the storm from 4am until 5:30pm today. I think it may just reach 75-80 mph at landfall, but hurricane force winds should remain offshore. For central Houston, we could be looking at occasional sustained winds in the 45-55 mph range from 10-11AM until late afternoon. There will be peaks and lulls, the wind won't always be that high. Gusts may reach 20 mph higher, or near hurricane force in central and southwest/west Houston. Closer to the coast, winds on Galveston and across Texas City, League City, etc., may reach 55-65 mph sustained with gusts 80-90 mph.

Rainfall on the order of 4-6 inches will be widespread, with totals over 10 inches in some areas.

Surge into Galveston Bay won't be too bad, given the very small area of high winds, perhaps 3-5 feet.

I'll be at work all day tomorrow riding it out. At least we have a generator and the AC is on generator power. I expect much of Houston will lose power tomorrow for a period from a few hours to a few days. We can be thankful this will just be a taste of tropical storm winds (considerably stronger than what we saw with Rita) and not hurricane-force winds through"

August 4, Edouard 1 pm update

A VARIETY OF WEATHER WILL IMPACT THE TERMINAL SITES OVER THE NEXT
24 HOURS. THE EVENTUAL TRACK AND STRENGTH OF EDOUARD IS THE MAIN
ISSUE...ALTHOUGH THE MODELS TO INDICATE AN ISOLATED CHANCE FOR
THUNDERSTORMS BETWEEN 21Z AND 03Z AT BOTH KCLL AND KUTS. THINK
THAT SUBSIDENCE AHEAD OF THE APPROACHING TROPICAL CYCLONE WILL
KEEP THE CONVECTION ELSEWHERE NIL INTO THIS EVENING. CONFIDENCE IN
THE FORECAST IS DEPENDENT UPON THE NHC FORECAST.

ACCORDING TO THE LATEST FORECAST FROM NHC...WINDS FROM EDOUARD
SHOULD BEGIN TO AFFECT KGLS AND KLBX BY AROUND MIDNIGHT...WITH
TROPICAL STORM FORCE WINDS DEVELOPING AT THOSE TWO SITES AND KHOU
AFTER 09Z. THE CURRENT FORECAST MOVES THE CENTER OF THE STORM OVER
BOTH SITES DURING THE MID MORNING PERIOD. TROPICAL STORM FORCE
WINDS ARE POSSIBLE AT KSGR BY AROUND 15Z. KIAH MAY NOT EXPERIENCE
TROPICAL STORM FORCE WINDS UNTIL TOWARD MIDDAY.

Tropical Storm Edouard Threat Update 7am

THIS STATEMENT RECOMMENDS ACTIONS TO BE TAKEN BY PERSONS IN THE FOLLOWING COUNTIES OR MARINE

AREAS:CHAMBERS...GALVESTON...HARRIS...LIBERTY.

...PRECAUTIONARY/PREPAREDNESS ACTIONS...

DAMAGING WINDS ARE EXPECTED.

MOST MOBILE HOMES WILL EXPERIENCE MODERATE DAMAGE. SOME OF POOR CONSTRUCTION WILL BE UNINHABITABLE UNTIL REPAIRED. HOUSES OF POOR TO AVERAGE CONSTRUCTION WILL HAVE DAMAGE TO SHINGLES...SIDING...ANDGUTTERS. SOME WINDOWS WILL BE BLOWN OUT. UNFASTENED HOME ITEMS OF LIGHT TO MODERATE WEIGHT WILL BECOME AIRBORNE...CAUSING ADDITIONAL DAMAGE AND POSSIBLE INJURY. DOZENS OF WIRES WILL BE BLOWN DOWN. LOCAL POWER OUTAGES WILL AFFECT ENTIRE NEIGHBORHOODS.MANY LARGE BRANCHES OF HEALTHY TREES WILL BE SNAPPED...AND ROTTING SMALL TO MEDIUM SIZED TREES WILL BE UPROOTED.

...WINDS...

TROPICAL STORM FORCE WINDS ARE EXPECTED TO BEGIN LATE MONDAY NIGHT AND PERSIST THROUGH THE MORNING HOURS ONTUESDAY. THE HIGHEST WINDS ARE EXPECTED TO OCCUR ACROSSCOASTAL AREAS OF BRAZORIA...GALVESTON...AND CHAMBERS COUNTIES WHERE SUSTAINED WINDS OF 50 TO 70 MPH ARE EXPECTED.ACROSS SOUTHERN LIBERTY AND EASTERN HARRIS COUNTIES SUSTAINED WINDS SHOULD PEAK IN THE 40 TO 60 MPH RANGE TUESDAYDURING THE MID TO LATE MORNING HOURS

....INLAND FLOODING...

AVERAGE RAINFALL AMOUNTS OF 2 TO 4 INCHES WITH ISOLATED AMOUNTS OF 6 INCHES ARE POSSIBLE...ESPECIALLY ALONGAND NEAR THE TRACK OF EDOUARD. THIS RAINFALL COULD PRODUCE SOME FLOODING PROBLEMS...ESPECIALLY ACROSS URBAN AREAS

....TORNADOES...

TORNADOES WILL BE A POSSIBILITY AS THE TROPICAL STORM APPROACHES AND RAIN BANDS BEGIN TO IMPACT THE COASTLINE.THIS THREAT SHOULD BEGIN MONDAY NIGHT AND PERSIST INTOTHE AFTERNOON HOURS ON TUESDAY.

10pm Edouard Threat Update

...WINDS...

TROPICAL STORM FORCE WINDS ARE EXPECTED TO BEGIN LATE
MONDAY NIGHT AND PERSIST THROUGH THE MORNING HOURS ON
TUESDAY. THE HIGHEST WINDS ARE EXPECTED TO OCCUR ACROSS
COASTAL AREAS OF BRAZORIA...GALVESTON...AND CHAMBERS
COUNTIES WHERE SUSTAINED WINDS OF 50 TO 70 MPH ARE EXPECTED.
ACROSS SOUTHERN LIBERTY AND EASTERN HARRIS COUNTIES
SUSTAINED WINDS SHOULD PEAK IN THE 40 TO 60 MPH RANGE TUESDAY
DURING THE MID TO LATE MORNING HOURS. COASTAL MATAGORDA
COUNTY CAN EXPECT TO SEE MINIMAL TROPICAL STORM FORCE WINDS
OF 35 TO 40 MPH. JACKSON COUNTY WILL ONLY SEE TROPICAL STORM
FORCE WINDS IF THE TRACK OF EDOUARD SHIFTS SOUTH...OR IF
EDOUARD STRENGTHENS TO A MINIMAL HURRICANE.

...INLAND FLOODING...

AVERAGE RAINFALL AMOUNTS OF 3 TO 5 INCHES WITH ISOLATED
AMOUNTS OF 8 INCHES ARE POSSIBLE...ESPECIALLY ALONG
AND NEAR THE TRACK OF EDOUARD. THIS RAINFALL COULD PRODUCE
SOME FLOODING PROBLEMS...ESPECIALLY ACROSS URBAN AREAS.

...TORNADOES...

TORNADOES WILL BE A POSSIBILITY AS THE TROPICAL STORM
APPROACHES AND RAIN BANDS BEGIN TO IMPACT THE COASTLINE.
THIS THREAT SHOULD BEGIN MONDAY NIGHT AND PERSIST INTO
THE AFTERNOON HOURS ON TUESDAY.

Tropical Storm Edouard 10pm Update

Not much change in the latest update with 00z models remaining in very good agreement for an upper Texas coast landfall Tuesday. There has been little change in the overall strength of the system but conditions should become more favorable for strengthening to occur over the next 24 hours and a Hurricane Watch has been issued for the Texas coast from Port O'Connor to Intercoastal City, LA which means Hurricane conditions are possible within in the next 36 hours.

Interestingly enough the BAMS model, which managed to correctly forecast the movement of Hurricane Rita back in 2005 continues to bring the system into or just south of Galveston Tuesday afternoon, so it will be interesting to watch is performance over the course of the next few days.

Tropical Storm Edouard 7pm Update : Threat to Houston

This is the latest word from the NWS as to what to expect if Edouard follows the 7pm update from the NHC. Again, if Edouard continues to strengthen faster than expected, then this forecast will have to be updated to increase the sustained winds.

...WINDS...

TROPICAL STORM FORCE WINDS ARE EXPECTED TO BEGIN LATE
MONDAY NIGHT AND PERSIST THROUGH THE MORNING HOURS ON
TUESDAY. THE HIGHEST WINDS ARE EXPECTED TO OCCUR ACROSS
COASTAL AREAS OF BRAZORIA...GALVESTON...AND CHAMBERS
COUNTIES WHERE SUSTAINED WINDS OF 50 TO 70 MPH ARE EXPECTED.
ACROSS LIBERTY...HARRIS...JACKSON...AND MATAGORDA COUNTIES
SUSTAINED WINDS SHOULD PEAK IN THE 40 TO 55 MPH RANGE.

...INLAND FLOODING...

AVERAGE RAINFALL AMOUNTS OF 2 TO 5 INCHES ARE EXPECTED
ACROSS THE WATCH AREA...WITH ISOLATED AMOUNTS IN THE 6
TO 8 INCH RANGE POSSIBLE. THIS COULD PRODUCE SOME
FLOODING PROBLEMS...ESPECIALLY ACROSS URBAN AREAS.

...TORNADOES...

TORNADOES WILL BE A POSSIBILITY AS THE TROPICAL STORM
APPROACHES AND RAIN BANDS BEGIN TO IMPACT THE COASTLINE.
THIS THREAT SHOULD BEGIN LATE MONDAY NIGHT AND PERSIST INTO
THE AFTERNOON HOURS ON TUESDAY.

5th Tropical Storm of the Season Threatens Houston

Tropical storm watches are currently up for the upper Texas coastline from Port O'Connor, TX to Intercoastal City, LA. As of 5pm, the National Hurricane Center as the center of Tropical Storm Edouard located at 28.1N 88.0W or about 95 miles south of the mouth of the Mississippi River or about 420 miles southeast of Galveston, TX. The storm is moving west at 6mph with a continued west or west northwest motion expected until landfall along the upper Texas coast, around Freeport Tuesday morning. At this time the Hurricane center currently keeps the system as a strong tropical storm at landfall; however the GFDL model continues to forecast Edouard to become a Hurricane before landfall. With water temps in the upper 80s across the northwest Gulf, there is the potential for the storm to undergo significant strengthening over the next 24 hours as the current forecast track takes the storm into an area with much less shear aloft.

The forecast models in the past have shown a leftward bias towards landfalling western gulf storms, which means they tend to forecast landfall to the left of where the storms actually ends up hitting the coast. At this time it does look however that the NHC is taking that into close consideration in their track forecast.

Rainfall from this storm should be extremely beneficial for southeast Texas with the current forecast calling for 2-6 inches widespread with isolated 6-8 inches in some spots.

5pm Track Forecast



5pm Tropical Storm Wind Prob



GOES Shear Tendency



Model forecast

Hot Weather to Continue through the weekend

Ever since Hurricane Dolly moved inland across south Texas, a large ridge of high pressure has dominated the weather over southeast Texas, keeping afternoon highs in the mid-upper 90s with heat indices's over 100 the past several days. Interestingly enough however, a rather stiff southerly breeze during the afternoons has helped keep ozone levels in the good range with no bad air days for the past week. I am planning on launching a ozone/radiosonde tomorrow at 1pm so it will be interesting to see the profile over the region. I will post the data plots once they become available.

We did see some isolated convection yesterday afternoon across Chambers and Liberty counties as a mid-level disturbance pumped some higher moisture levels out of the western gulf and into the region; however a very strong mid-level cap inhibited most of the shower activity one would expect from precip-water values in the 1.8-2.0'' range.

Both the 12z and 18z GFS model runs show building 500mb heights over the central plains down into southeast Texas with a 594DAM center located over Arkansas, Missouri, and eastern Oklahoma. This along with dew points forecast to drop into the mid 60s over much of the region should easily allow temps to warm to at or above 100 degrees Monday afternoon.

Some relief could be in the forecast starting Tuesday as models bring increased moisture on the east side of an inverted trough which will be moving inland across the upper/middle Texas coastline Tuesday/Wednesday of next week.

GFS Forecast Surface Temps 00z Tuesday (6pm Monday)



NWS Weekend Outlook

Weather Forecasting Contest

Here's the link to National Weather Forecast competition:

www.wxchallenge.com

here are the rules 

Much Needed Rain Falls Over Houston

The remnants of Dolly continue to spin over east central Mexico at this hour with rain dieing down across the state due to the loss of daytime heating. Much needed rain fell this afternoon across metro Houston as an area of speed/moisture convergence set up across our coastal counties and caused fired off round after round of showers and thunderstorms through the evening. Some locations that received the heaviest rain included Stafford, Alief, Shaprstown, Memorial Villages, downtown Houston, and eastern sections of Harris county from Deer Park, Sheldon, and up to the east of Kingwood. Harris county gauges and KHGX storm total estimates show that the aforementioned areas saw anywhere from 1-5 inches of rain with most everyone else seeing a nice 0.5-2'' of rain. There were only a few reports of some street flooding, mainly caused by the intense rainfall rates under the stronger storms.

Activity has completely dissipated over southeast Texas this evening but with deep tropical moisture in place, can't rule out some isolated shower activity re-developing near the coast after midnight. I am not completely convinced that tomorrow will be as dry as the current NWS forecast is calling for since a lot of moisture remains off to our east and northeast. After glancing at some model soundings, it looks like we will have a breakable cap and attainable convective temps along with some decent moisture around; therefore it looks like we could be in for another round of more scattered convective activity tomorrow afternoon.

The weekend looks hot as a strong ridge of high pressure builds in from the north. Ground moisture should remain high so dew points are expected to remain in the low to mid 70s which could lead to some dangerous heat index numbers as temps warm into the upper 90s. Extended models want to try and break the ridge down by the middle part of next week, which could signal a return to afternoon and evening shower and thunderstorm activity.

Official Storm Totals as of 5pm this evening

Bush Airport : 0.69''
Houston Hobby: 0.75''
Pearland: 0.85''
Sugar Land: 1.54''
Tomball: 0.80''
Conroe: 0.20''
Huntsville: T
Angelton: 0.68''
NWS Office: 1.38''
Mission Bend 1.4m N: 2.46'' (My House)

KHGX Storm Total Precip

Training rains over much of Houston

Will make this quick and will have a complete update later this evening but showers and thunderstorms continue to train over western and eastern sections of Harris county with downtown Houston in the clear at the moment. A quick check of the RUC-2 model analysis shows good moisture convergence continues across northern sections of Galveston and Brazoria counties where showers and being initiated before growing in intensity over Harris county. With very high moisture levels over the area, these storms are putting down 1-2 inches of rain per hour and there have been reports of some minor street flooding in your typical flood prone areas. With very low convective temps, look for the possibility of additional rain through the evening with things calming down after sunset.

The KHGX 3 hour rainfall total shows a large swath of 1.5-2.75'' rain amounts across the western sections of the city and then right across downtown Houston. At the moment though, downtown looks to just be getting some scattered rain with the more organized stuff across areas west of Beltway 8 where another 1-2 inches is possible over the next hour.

KHGX 3-Hour Precip Estimate

Dolly Brings Afternoon Rain

As the center of Dolly gets ready to exit the US into central Mexico, the large synoptic circulation continues to bring up very deep tropical moisture out of the western gulf and into southeast Texas. The latest RUC-2 analysis shows precip water values remain in the 2.2-2.4'' range over the region along with strong moisture flux convergence along our coastal counties. After a brief break this morning, some daytime heating around noon has helped kick off another round of showers and thunderstorms this afternoon. Storm motions continue to be rather high which should help to limit the flooding potential unless we see training of storms develop. Rainfall rates will be quite high in the stronger storms due to the amount of moisture in the atmosphere.

We should see things start to die down this evening with the loss of daytime heating. The weather for Friday should be much improved with a return to hot/humid weather for the weekend as a strong ridge of high pressure settles into our part of the state.

Dolly Update 2 / Hou Forecast Discussion

The 12pm update from the NHC and latest radar imagery show that center Dolly has pretty much come to a halt over south Padre Island with a slight drift to the northwest. Most of the ASOS sites near the center have lost power, but the last reading (11:31am) from Port Isabel had northeast winds at 54mph gusting to 70mph with a peak gust of 72mph. Look for the storm to resume a northwest motion around 7mph in a couple of hours.

Locally, Houston has been in between two developing feeder bands, one located across Brazoria county with the other extending from southwest LA, west/northwest across Beaumont, central Liberty county, and back towards KIAH. So far rainfall has been rather light; however a lot of moisture will continue to stream northward out of the gulf over the next 24-36 hours as Dolly slowly moves inland across south Texas. As we head into the afternoon look for scattered showers and thunderstorms to develop across areas north of I-10 as temps warm towards our convective temps. With precip-water values expected to remain in the 2.2-2.4'' range this afternoon and overnight, any of the stronger storms will have the potential for putting down 2-3 inches of rain per hour, therefore if we see training develop, some areas could experience some urban flooding problems.

As far as the winds are concerned, my forecast from last night looks to be holding up pretty well with winds at UHMT this afternoon in the 15-25mph range and the RASS profiler at UHCC showing east winds at 20-25mph with 40mph winds (35kts) around 1km. Look for these breezy conditions to continue through the afternoon as the pressure gradient remains tight around Dolly's circulation. As she moves inland this afternoon, look for winds to slowly die down through the evening.

KBRO Reflectivity



KHGX Reflectivity

Dolly Update 1 / Hou Forecast

Quick update this morning on Dolly. The 6am update shows dolly about 55 miles east of Brownsville, TX moving off to the northwest around 8mph. She is currently forecast to make landfall around noon just north of Brownsville as a strong Cat 1 or possibly Cat 2 hurricane. The latest surface obs from south Texas show tropical storm force winds already moving onshore with strong rain bands now moving into south Texas. See below for a very impressive radar display of the storm.

Locally, we have already seen one heavy band of thunderstorms associated with Dolly move across the city this morning with UHMT H-Net site picking up around 1.25'' of rain in just less than an hours time. The 11z RUC-2 model shows some very impressive precip-water values (2.2-2.4'') already in place over southern and central sections of southeast Texas with a lot more poised to move in during the day on a strong 20-30kt low level jet. The latest radar imagery shows a lot more activity out over the gulf which will likely move across the area through the day. Right now it looks like most areas should pick up about 1-2 inches of rain with some spots seeing 2-5'' where training develops.

As far as winds are concerned, it still looks like my previous forecast will hold up rather well today. We will see stronger winds in the rain bands as UHMT reported winds up to 25mph as this mornings band moved through. We will likely see winds pick up into the 10-20mph range later this morning as the sun comes up and helps to mix down some of the strong winds just above the surface.

KBRO Reflectivity (7:28am)



11z RUC-2 Precip-Water



11z RUC-2 850mb winds/ Td

Hurricane Dolly

The latest (7pm intermediate) advisory on Dolly continues to show that the storm has strengthened little since this afternoon, with max sustained winds still clocked 75mph or minimal Cat 1 strength. The storm does look rather impressive on the KBRO radar display with a nicely defined northwest eye wall (See below for image) and some strengthening is possible before landfall tomorrow morning.The early cycle 00z model track guidance is in somewhat better agreement than the 18z run with the models very tightly packed now along the northern Mexican/far southern Texas coastline. The NAM and HWRF look to continue to be the outliers and continue to show the storm making landfall much further north, over Corpus Christi. This is likely because they want to stall the storm out later tonight just off the Texas coastline which would help pull it further north around a retreating area of high pressure. This however looks unlikely as Dolly continues to remain on a steady path to the northwest at 11mph.

Locally, we have seen rather breezy conditions this afternoon across Houston and surrounding areas as the pressure gradient tightens up across the region. With the storm expected to make landfall well south of the area, I would expect to see winds calm down a bit overnight with 10-15mph winds prevailing, especially along the coast. Tomorrow we should see winds pick back up into the 15-20mph range with higher gusts, especially if we manage to see any outer squalls from Dolly work there way onshore. The main threat from the Hurricane will be the potential for some locally heavy rainfall late tonight along the coast and then spreading inland during the morning. As we have seen this evening, storm motions will remain rather quick, so it will take training of the rain bands to get any significant rainfall amounts. Thursday could remain active as deep tropical moisture will remain over the area; however by Friday another ridge of high pressure will build in from the north and set the stage for a hot and relatively dry weekend.

H-Net Wind Forecasts

UHMT: Tonight 10-15mph
Wednesday: 15-25mph
UHCC: Tonight: 15-20mph
Wednesday: 20-25mph

KBRO Radar Display (9:54pm) Reflectivity



KBRO Radar Display (9:54pm) Base Velocity



Early Track 00z Model Guidance



18z Model's