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

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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