July: Week of 25th - Don Near S TX/ Hot & Dry

[srainhoutx]

With 90L lurking in the NW Caribbean moving WNW located S of Western Cuba, our rainfall chances look to increase as we head toward the end of the week...

[redneckweather]

An hour of lightning, and 43 drops of rain...

Same here. How exciting.

[srainhoutx]

Activity will likely increase for our Weather Forum with tropical disturbance 90L (near the Yucatan Channel) forming and RECON heading out to investigate later today. Folks will need to follow development closely as we may have issues along the Upper TX Coast depending on track and intensity. Stay Tuned as they say... NWS Houston/Galveston early morning discussion...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
420 AM CDT WED JUL 27 2011

...MONITORING A TROPICAL DISTURBANCE IN THE NW CARIBBEAN...

.DISCUSSION...
THE REALITY IS THAT THERE WILL BE QUITE A BIT OF MOISTURE AND
ENOUGH OF A WEAKNESS IN THE UPPER LEVEL RIDGE TO AT LEAST SUPPORT
SOME THUNDERSTORM ACTIVITY ACROSS SE TX TODAY AND TOMORROW. POPS
WILL STILL RANGE FROM 20 TO 30 PERCENT EACH DAY AND REMAIN HOT
WITH MAX TEMPS REACHING THE LOW 100S INLAND. HEAT INDEX VALUES
WILL PROBABLY REACH CLOSE TO 107F IN A FEW LOCATIONS.

BUT THE MAIN TOPIC OF DISCUSSION IS THE TROPICAL DISTURBANCE IN
THE NW CARIBBEAN. IR SATELLITE REPRESENTATION LOOKS FAIRLY DECENT
WITH DEEP CONVECTION AROUND WHAT APPEARS TO BE A CENTER OF
CIRCULATION. NHC GIVES THIS A 70 PERCENT CHANCE OF BECOMING A
T.D. BUT THINK THE ODDS ARE THAT THIS SYSTEM IS ON ITS WAY TO
BECOMING A TROPICAL SYSTEM. AIRCRAFT RECON WILL FLY INTO THE
SYSTEM LATER TODAY AND DATA WILL LIKELY DETERMINE THE STATUS OF
THE SYSTEM. THE TRACK FORECAST OF THIS SYSTEM IS OF PARTICULAR
INTEREST BECAUSE QUITE A FEW OF THE TROPICAL MODEL GUIDANCES
BRING THE SYSTEM TO THE UPPER TX COAST. THERE IS STILL SOME
SPREAD AMONG THE GUIDANCE BUT THE NAM/GFS SEEM TO BRING THE
SYSTEM TOWARDS THE TX COAST AS WELL. FUTURE MODEL GUIDANCE SHOULD
HELP WITH THE TRACK FORECAST AS THEY WILL BENEFIT FROM A MORE
DEVELOPED SYSTEM. RIGHT NOW THE FORECAST FOR FRIDAY WILL BE ON
THE CONSERVATIVE SIDE GIVEN UNCERTAINTY SURROUNDING THE
DEVELOPMENT OF THE SYSTEM AND HOW MODEL GUIDANCE HANDLE WEAK
SYSTEMS RATHER POORLY. THAT SAID A MORE NW TRACK MAKES MORE SENSE
AS THE UPPER LEVEL RIDGE SHOULD BE LOCATED OVER THE CAROLINAS BY
THU NIGHT. RIDGES AT 700/850MB WILL ALSO BE LOCATED IN THIS
GENERAL AREA WITH A WEAKNESS OVER THE NW GULF THROUGH TX. GIVEN
THE FLOW AROUND THE RIDGE...THINK THIS SYSTEM FOR NOW WILL TRACK
AROUND THE RIDGE IN THE GENERAL DIRECTION OF THE TX COAST. THE
INTENSITY OF THE SYSTEM WILL BE CLOSELY WATCHED. RIGHT NOW THE
SYSTEM HAS WARM WATERS TO PASS THROUGH IN THE NW CARIB AND S
GULF. SHEAR IS ALSO QUITE WEAK BUT AS NOTED IN UPPER AIR
SOUNDINGS AND ANALYSIS...THERE IS QUITE A BIT OF EASTERLY SHEAR
ACROSS THE NORTHERN HALF OF THE GULF. THE SHEAR IS FORECAST BY
BOTH THE NAM/GFS TO WEAKEN SOME BUT THE MAIN QUESTION WILL BE HOW
MUCH EFFECT THE SHEAR HAS ON THE SYSTEM AND ITS INTENSITY.

WITH ALL THAT SAID...POPS WERE INCREASED TO AROUND 50 PERCENT FOR
FRIDAY BUT COULD CERTAINLY GO HIGHER DEPENDING ON THE TRACK OF THE
SYSTEM. MAX TEMPS WERE DROPPED A COUPLE DEGREES MORE IN LINE WITH
SOME OF THE GUIDANCE BUT SHOULD THE SYSTEM IMPACT SE TX...MAX
TEMPS WILL LIKELY BE IN THE 80S WHICH WOULD BE A WELCOME BREAK
FROM THE HEAT. RAINFALL AMOUNTS ARE CONSERVATIVELY A 0.50 TO 1.00
INCH BUT HEAVY RAINFALL WILL BE A GROWING THREAT DEPENDING ON THE
TRACK. ALSO KEPT POPS AROUND 30 PERCENT OVERNIGHT AND 20 PERCENT
ON SATURDAY FOR ANY LINGERING ACTIVITY AFTER THE SYSTEM MOVES
INLAND.

IF THE TROPICAL DISTURBANCE TAKES A MORE SOUTHERN TRACK AND
RAINFALL MISSES SE TX...DROUGHT CONDITIONS WILL REALLY WORSEN. BY
SAT/SUN THE UPPER LEVEL RIDGE EXPANDS INTO THE PLAINS AND
STRENGTHENS. THE RIDGE WILL REMAIN IN PLACE MON/TUE NEXT WEEK AND
BE STRONG ENOUGH TO INHIBIT THUNDERSTORM ACTIVITY. MAX TEMPS
WILL BE BACK IN THE UPPER 90S/LOW 100S. HEAT INDEX VALUES WILL
NEED TO BE WATCHED FOR POSSIBLE HEAT ADVISORIES. SE TX COULD VERY
WELL HAVE HEAT INDEX VALUES TOPPING OUT NEAR 110F. MIN TEMPS WILL
ALSO BE ON THE WARM SIDE WITH NOT A LOT OF OVERNIGHT COOLING.


Follow our discussions and analysis in our Hurricane Central section (link provided below) and if the disturbance develops and Official Advisories are issued by the National Hurricane Center or NWS offices along Coastal Texas, we will post such Advisories/Watches/Warnings on our main page as well.

Hurricane Central 90L Discussions Link...
http://forums.khou.com/viewtopic.php?f= ... &start=100

[srainhoutx]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
355 PM CDT WED JUL 27 2011

...TROPICAL STORM DON FORMS IN THE SOUTHERN GULF OF MEXICO...

.DISCUSSION...
NHC HAS DECLARED THAT THE TROPICAL DISTURBANCE JUST NORTH OF THE
YUCATAN HAS STRENGTHENED TO TROPICAL STORM DON. THE SYSTEM IS
FORECAST TO SLOWLY INTENSIFY AS IT TRACKS NORTHWESTWARD OVER THE
NEXT COUPLE OF DAYS. THE STORM IS EXPECTED TO MAKE LANDFALL ALONG
THE MIDDLE TEXAS COAST FRIDAY NIGHT. THE CURRENT FORECAST TRACK OF
THE SYSTEM WOULD RESULT IN IMPACTS ACROSS SE TX IN THE FRIDAY
THROUGH SATURDAY TIME FRAME.

HIGHLY MOIST AIRMASS REMAINS IN PLACE ACROSS SE ZONES (PWS 2.1-2.3
INCHES) WHILE SOME DRYING HAS OCCURRED OVER THE WESTERN ZONES (PWS
DOWN TO 1.7 INCHES). CONVECTIVE COVERAGE HAS SO FAR BEEN RATHER
SPARSE EXCEPT OVER THE FAR EASTERN ZONES. ONGOING ACTIVITY SHOULD
DISSIPATE THIS EVENING WITH THE LOSS OF DAYTIME HEATING. MODELS
FORECAST SCATTERED CONVECTION AGAIN THURSDAY ESPECIALLY ACROSS THE
NORTHEAST TWO-THIRDS OF THE AREA WHERE PWS ARE FORECAST TO REMAIN
2.1-2.3 INCHES. ATMOSPHERE WILL REMAIN UNCAPPED WITH DAYTIME
HEATING RESULTING IN CONVECTIVE DEVELOPMENT. SUBSIDENCE AROUND THE
PERIPHERY OF THE TROPICAL STORM MAY BEGIN TO AFFECT THE COASTAL
AREAS THURSDAY AFTN...AND WILL SPREAD ACROSS ALL OF SE TX RESULTING
IN A TEMPORARY LULL IN CONVECTIVE DEVELOPMENT. HAVE KEPT MOST OF
THE CWA DRY FOR THURSDAY NIGHT. HAVE GONE WITH PERSISTENCE FOR
TEMPS THROUGH THIS PERIOD.

OUTER CONVECTIVE BANDS WITH TROPICAL STORM DON WILL BEGIN TO
AFFECT THE COASTAL WATERS EARLY FRIDAY AND WILL SPREAD ACROSS SE
TX FRIDAY AFTERNOON/EVENING. WITH THE STORM FORECAST TO MAKE
LANDFALL JUST WEST OF THE CWA AS A TROPICAL STORM...THE MAIN
IMPACTS WOULD BE HEAVY RAINFALL AND THE POSSIBILITY OF ISOLATED
TORNADOES...ESPECIALLY ACROSS THE WESTERN PORTIONS OF THE CWA.
SEVERAL FACTORS MAY HELP MITIGATE THE OVERALL POTENTIAL FOR INLAND
FLOODING: THE SMALLER AREAL SIZE OF THE STORM...THE STEADY
FORWARD SPEED...AND OF COURSE THE ONGOING EXCEPTIONAL DROUGHT.
BASED ON THE CURRENT FORECAST TRACK...TROPICAL STORM FORCE WINDS
WILL BE POSSIBLE OVER THE SOUTHWEST ZONES AND ALONG THE WESTERN
COASTAL AREAS...ALONG WITH MINOR TIDAL FLOODING ALONG THE
IMMEDIATE COAST AND BAYS. THERE IS STILL CONSIDERABLE UNCERTAINTY
IN THE TRACK AND INTENSITY FORECAST. PERSONS ACROSS SE TX SHOULD
CLOSELY MONITOR THE LATEST FORECAST INFORMATION FROM NHC.

HAVE GENERALLY INCREASED POPS AND CLOUD COVER AND LOWERED
TEMPERATURES FOR THE FRIDAY THROUGH SATURDAY PERIOD.

TROPICAL STORM DON WILL MOVE QUICKLY INLAND AFTER LANDFALL AND
WILL BE OUT OF THE AREA BY SATURDAY EVENING. SOME ISOLATED
CONVECTION COULD PERSIST SATURDAY NIGHT WITH LINGERING MOISTURE.
THE UPPER LEVEL RIDGE OF HIGH PRESSURE WILL SPREAD BACK ACROSS
TEXAS BEGINNING SUNDAY AND STRENGTHEN THROUGH THE FIRST PART OF
NEXT WEEK. BASED ON MODEL CONSISTENCY AND FORECAST 850 MB
TEMPS...IT LOOKS LIKE THE HOTTEST TEMPERATURES SO FAR OF THIS
VERY HOT SUMMER ARE LIKELY NEXT WEEK. EVEN THE CONSERVATIVE MEXMOS
IS FORECASTING HIGHS CLOSE TO 100 DEGREES IN HOUSTON. HAVE BUMPED
UP TEMPS MONDAY THROUGH WEDNESDAY. KEPT 20 POPS GOING EACH DAY FOR
POSSIBILITY OF SOME ISOLATED DIURNAL CONVECTIVE DEVELOPMENT.

[srainhoutx]

There is some hope that TS Don will provide the area with some badly needed rain beginning late Thursday through Saturday. The HPC QPF discussion offers some hints...fingers crossed...

...TROPICAL STORM DON...

PER THE NHC... BY THE START OF DAY 2... 12Z/29... T.S. DON IS
FORECAST TO BE ABOUT 220 MI SE OF CORPUS CHRISTI. THE GUIDANCE
GENERALLY TAKES THIS STORM WEST NORTHWESTWARD AND THE OFFICIAL NHC
TRACK FORECAST PROJECTS A LANDFALL IN SOUTHEASTER TEXAS FRI NIGHT
OR EARLY SAT MORNING. MODELS ARE TOO WEAK WITH THIS SYSTEM AND
THUS THEIR QPFS ARE LIKELY WAY UNDERDONE. HPC QPF WILL ASSUME
SUFFICIENT CONVECTIVE ORGANIZATION FOR HEAVY RAINFALL TO OCCUR
ALONG THE MIDDLE TX COAST AND THEN WELL INLAND TOWARD THE HILL
COUNTRY OVER THE WEEKEND. SEVERAL INCHES OF RAIN SHOULD FALL IN A
VERY PARCHED AREA OF THE STATE BUT THE SMALL SIZE AND STEADY
MOVEMENT SHOULD PRECLUDE WIDESPREAD FLOODING. FEEDER BAND ENHANCED
RAINFALL IS POSSIBLE NORTH OF THE CENTER WITH GOOD INFLOW OFF THE
GULF BUT DID NOT GET CUTE WITH THE QPF AT THIS POINT GIVEN THE
POOR MODEL AGREEMENT. PLEASE REFER TO THE LATEST NHC ADVISORIES
FOR MORE INFORMATION ON DON.

HPC Short Range Forecast...

...TROPICAL STORM DON EXPECTED TO TRACK THROUGH GULF OF MEXICO
TOWARD TEXAS COAST...

...HEAVY RAINS MAY DEVELOP OVER PORTIONS OF THE TEXAS COAST...

...SLIGHT RISK OF SEVERE THUNDERSTORMS EXTENDS FROM THE GREAT
LAKES TO THE CENTRAL PLAINS...

TROPICAL STORM DON IS FORECAST TO CONTINUE ON A NORTHWEST TRACK
THROUGH SATURDAY TOWARDS THE SOUTHERN TEXAS COAST. PLEASE REFER
TO http://WWW.NHC.NOAA.GOV FOR THE LATEST INFORMATION ON DON. DEEP
TROPICAL MOISTURE ACROSS THE GULF COAST ... PARTLY ASSOCIATED WITH
TROPICAL STORM DON ... WILL KEEP SHOWERS AND THUNDERSTORMS IN THE
FORECAST FROM THE NORTH CENTRAL GULF COAST INTO THE UPPER TEXAS
COAST THROUGH FRIDAY ... WITH HEAVY RAINS ALONG THE TEXAS COAST
FRIDAY EVENING INTO SATURDAY.

[djjordan]

Even with a possible Corpus landfall I'm hoping Don has enough umph to slug some moisture our way and enhance rain chances. We need a heavy rain event. That goes without saying.

[C2G]

Nice heavy rain with some lightning. Two days in a row, it's a pattern by golly.

[djjordan]

Nice heavy rain with some lightning. Two days in a row, it's a pattern by golly.

LOL ..... Perhaps that trend will continue kinda wish I could get a good downpour for a few days in a row .... that would be awesome for my lawn and foundation.

[C2G]

LOL ..... Perhaps that trend will continue kinda wish I could get a good downpour for a few days in a row .... that would be awesome for my lawn and foundation.

Yup, doors are magically opening again without extreme force. Looks like some nice showers are developing again today. Plenty of Gulf moisture flowing onshore.

[C2G]

Another day.......another Gully washer.
Three days in a row's definitely a pattern, at least for Friendlywood.

[djjordan]

Looking good .....send it to Sugar Land please Ha ha ..... chance of rain looks good today for nearly everyone. 3 days in a row .... that's gotta be a record LOL.

[srainhoutx]

Hearing rumbles of thunder and some light sprinkles in NW Harris County at this time. TC's have really increased in the past hour or so...

[txflagwaver]

Thunder, wind picks up....thunder fades, wind dies down, sun back out...same conditions, different day

[CAK]

Whats with the anti-rain force field around Houston? All day I've been watching moisture surge just to reach Houston and dissipate just to reform again over Conroe area. NWS says "12Z soundings show no capping with convective temps only in the mid to upper 80's." Argh!

[mckinne63]

Finally getting a nice storm in Stafford. It's been cloudy and windy most of the day. Would look like it was going to rain, but nothing. Hearing some thunder too. Hope the rain hangs around for awhile and doesn't clear out quickly.

[tireman4]

To end July on a lovely note, here now is the National Weather Service HGX:

40

CLIMATE...
JULY IS IN THE BOOKS AND IT WAS THE THIRD WARMEST JULY ON RECORD
FOR THE CITY OF HOUSTON...THE SECOND WARMEST JULY ON RECORD FOR
GALVESTON AND TIED FOR THE SECOND WARMEST JULY AT COLLEGE STATION.
IT WAS ALSO THE SEVENTH DRIEST JULY ON RECORD FOR COLLEGE STATION.
IT WAS THE THIRD WARMEST JULY ON RECORD FOR HOBBY AIRPORT.

THE NEW 1981-2010 CLIMATE NORMALS BECOME OPERATIONAL LATER TODAY.
THE CHANGE WILL BE REFLECTED WITH THE AFTERNOON DAILY CLIMATE
SUMMARY.

Sigh....


http://forecast.weather.gov/product.php ... glossary=1