Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 4

[DoctorMu]

CAPE between 2500-3000 J/kg. DP = 76° We have some convergence just N of CLL..cumulus clouds piling up in the soupy air like a chain reaction wreck on LA's 105.

000

FXUS64 KHGX 121549

AFDHGX

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX

1049 AM CDT TUE JUN 12 2012

.UPDATE...

TRICKY FORECAST THIS MORNING AS MOST OF THE HIGHER RES MODELS DO

NOT APPEAR TO HAVE INITIALIZED WELL WITH THE MCS TO OUR EAST.

SURFACE WINDS SHOW A BIT OF CONVERGENCE ACROSS OUR NORTHERN

COUNTIES AND A FEW SHOWERS HAVE DEVELOPED IN THIS AREA OVER THE

LAST HOUR OR SO. HAVE INCREASED POPS ACROSS THE NORTHERN HALF OF

THE REGION THROUGH THIS EVENING AND ADDED A MENTION OF ISOLATED

SEVERE ACROSS OUR NORTHEASTERN COUNTIES THIS AFTERNOON. 38

[Srain]

Afternoon e-mail from Jeff:

Severe thunderstorms erupting over our northern counties at present time along old outflow boundary from this morning complex over LA. At the same time upstream thunderstorm complex over NW TX has been growing in intensity and size and SPC has issued a severe thunderstorm watch to cover this incoming activity. Based on current trends, expect thunderstorms to affect many areas north of I-10 and possibly south of I-10 from now through the mid evening hours. Severe threat will be based on damaging winds and large hail in this strongly unstable air mass. Based on current trends the more aggressive meso models showing more widespread development may have been on the right track for today.

Severe Thunderstorm Watch and Radar Overlay:

[Srain]

From NESID:

SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678

LATEST DATA USED: GOES-13 1815Z RUMINSKI

.

LOCATION...TEXAS...

.

ATTN WFOS...LCH...SHV...HGX...FWD...SJT...

ATTN RFCS...WGRFC...

.

EVENT...HEAVY RAIN EVENT SETTING UP FOR EAST TEXAS

.

SATELLITE ANALYSIS AND TRENDS...LATEST STLT IMAGERY SHOWING TWO

AREAS OF ACTIVE CD TOPPED CNVTN NR KSEP/KMWL AND NEAR KJAS WITH WELL

DEFINED BOUNDARY BTWN THEM. CNVTN NR KSEP/KMWL ALSO SHOWING CYCLONIC

ROTATION IN THE LOW LEVEL CU FIELD WHICH IS AIDING LOW LEVEL MOISTURE

CONVERGENCE. LATEST GOES DERIVED SOUNDER PRODUCTS SHOW CNVTN IS FIRING

ALG AXIS OF HIGHEST PW VALUES (1.75" TO 2") WITH VERY HIGH CAPE (ARND

5000J/KG) AND DIMINISHING CINH. CNVTN IS BACKBUILING INTO POLK/TRINITY

ALG OUTFLOW BOUNDARY AND EXPECT THIS TREND TO CONT THRU THE AFTN/EVE

AND MERGE WITH CNVTV COMPLEX TO THE W AS IT SHIFTS TO THE E. EXPECT

HEAVY RAIN AREA ALG AN ERATH TO POLK AXIS WITH RAINFALL AMNTS OF 2.0"

TO 2.5"/HR PSBL UNDER CNVTV CORES.

.

AN ANNOTATED SATELLITE GRAPHIC SHOWING THE HEAVY PRECIPITATION THREAT AREA

SHOULD BE AVAILABLE ON THE INTERNET ADDRESS LISTED BELOW IN APPROXIMATELY

10-15 MINUTES.

.

SHORT TERM OUTLOOK VALID 1900-2200Z...MEDIUM HIGH CONFIDENCE FACTOR

IN SHORT

TERM OUTLOOK...EXPECT CNVTV LN FROM HOOD TO BROWN COUNTIES TO CONT

PROPAGATING TO THE E WITH CNVTN FILLING IN ALG OLD OUTFLOW BOUNDARY ON

NORTHERN FLANK ALG A HOOD TO HOUSTON AXIS. WITH PSBLY OF REPEAT CNVTN

ALNG THIS LN LOCALIZED 3 HR RAINFALL TOTALS OF 3-4" PSBL.

[PottercountyWXobserver]

Looks like some action is slowly approaching the greater Houston area. Not to mention some possible bonus rains behind the t-storms. Hopefully that bonus rain holds up as it pushes to the south.

[Srain]

SE Texas including the Houston Metro under a Severe Thunderstorm Watch until 10:00PM CDT

[Ed Lizard]

Wind increased at HOU from South with a rise in the dewpoint the last hour, and while I'm not seeing it on vis imagery or radar, if there was an seabreeze headed in to meet the storms coming down from Montgomery County, well, that'd be awfully interesting.

[DoctorMu]

Things are beginning to rock out there, and hoping for an outflow boundary NW TX T-storm complex sandwich in CLL. 5000 J/kg - I can believe it. The show's on!

Severe T-storm watch until 10 pm

[PottercountyWXobserver]

I'm not quite familiar with Houston's weather quite yet, but I'm assuming the sea breeze adds extra lift? Looks like some much need rain is on the way, hopefully the El Nino on the way, postive departs will start showing up towards winter and next spring time. Haha and just think, all this action when NWS was saying 20%. I'm sorry for the noob TX questions, I promise it doesn't take me long to learn the climate of the area.

Hopefully we can get all surrounding areas some good rain, moisten up that ground as it will do wonders to help keep down those summer temps.

[Srain]

Nice rotation between The Woodlands and Spring along I-45 N

[Srain]

Getting multiple reports of trees down across S Montgomery County

[DoctorMu]

Getting multiple reports of trees down across S Montgomery County

looked like some rotation moving S just E of IAH?

Just had a straight line wind of 40+ here

a wimpy post oak down here - but, hey, it's a victim!

[DoctorMu]

want a little mustard on that sandwich?

https://twitter.com/...2807168/photo/1

... SIGNIFICANT WEATHER ADVISORY FOR BURLESON... WASHINGTON... NORTHWESTERN AUSTIN... NORTHWESTERN COLORADO... SOUTHWESTERN GRIMES AND BRAZOS COUNTIES UNTIL 730 PM CDT...

AT 554 PM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A LINE OF STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 12 MILES NORTHWEST OF BRYAN TO 9 MILES SOUTH OF CALDWELL TO 8 MILES NORTHEAST OF BASTROP... AND MOVING SOUTHEAST AT 20 MPH.

HAIL UP TO THE SIZE OF PEAS AND WIND GUSTS UP TO 40 MPH WILL BE POSSIBLE WITH THESE STORMS.

LOCATIONS IMPACTED INCLUDE... COLLEGE STATION... BRYAN... BRENHAM... NAVASOTA... SOMERVILLE... SNOOK AND BURTON.

[PottercountyWXobserver]

Here is a need little link I though you guys might like.

http://hint.fm/wind/

[Srain]

I suspect the pattern that is unfolding is similar to what we saw in 1989. Hurricane Cosme made landfall near the Gulf of Tehuantepec in the EPAC and left over energy developed into what would become Tropical Storm Allison in the Western Gulf in late June of that year. We will keep an eye on the developing 94E in the EPAC on the Main Page Tropical Discussion threads that Josh is hosting, as guidance suggests a somewhat similar setup. The pattern does suggest increased moisture in the Western Caribbean/Western Gulf as the monsoonal trough lifts N and multiple areas of vorticity develop within the monsoonal gyre of a broad area of low pressure near the Bay of Campeche. Forecaster Roth covers this in the HPC overnight extended forecast...

ELSEWHERE...A RETROGRADING REX BLOCK MOVED FROM THE 60TH PARALLEL

TOWARDS THE EAST COAST...WITH ITS SOUTHERN MEMBER DRAGGING A COLD

FRONT THROUGH NORTHWEST CUBA...SOMEWHAT UNUSUAL FOR MID TO LATE

JUNE. DUE TO THE RETROGRADING UPPER LOW BETWEEN BERMUDA AND THE

SOUTHEAST...DISTURBED WEATHER/A BROAD AREA OF LOW PRESSURE IS

EXPECTED ACROSS THE WESTERN CARIBBEAN...WHICH MAY DRIFT NORTHWEST

TOWARDS THE YUCATAN CHANNEL BY NEXT WEDNESDAY. GENERAL RIDGING

ACROSS NORTHWEST MEXICO AND INCREASINGLY ACROSS THE SOUTHWEST

FAVORS DISTURBED WEATHER WITHIN THE TROPICAL EASTERN PACIFIC...AND

THE 12Z GLOBAL ENSEMBLE GUIDANCE SHOWS TWO PROSPECTS FOR

DEVELOPMENT OVER THE NEXT WEEK IN THIS REGION. SATURDAY SEEMS TO

BEST CHANCE FOR THUNDERSTORMS ACROSS ARID NEW MEXICO...BUT EVEN

THEN THEY SHOULD BE SCATTERED TO WIDELY SCATTERED IN NATURE AND

COULD DO MORE HARM THAN GOOD.

[Srain]

We have a somewhat challenging forecast today as a MCS is ongoing near N Texas once again with left of boundaries across the region. Guidance is not very keen on developing anything like we saw yesterday, but with lack luster confidence in the shorter range meso models, it is prudent to at least follow developments throughout the day. Storms are firing near the Coast and the upstream activity shows some development SE as the short wave moves across the region this afternoon/evening.

[Srain]

Morning e-mail from Jeff:

More uncertainty today with respect to storm coverage and intensity this afternoon.

Large complex of storms that erupted over the northern ½ of the region yesterday which produced the damaging winds and widespread power outages have left behind a large outflow boundary which extends from SW TX to south of Victoria to off the upper TX coast. This boundary appears to be starting to lift northward and moisture returning with radar showing isolated to scattered showers over the nearshore waters into the coastal counties. Air mass was worked over pretty good by the convection yesterday and suspect it will take much of the morning and into the afternoon to recover…and even then instability does not look nearly as great as yesterday. With that said, there is a large weakening complex of storms from Fort Worth to Brownwood with a large outflow boundary likely moving SE along/ahead of this activity. This complex is tied to a short wave over SW OK which will drive SE today in the upper level NW flow aloft. Short term meso models do not show much if any development today across the area as they weaken the current complex and do not show re-development this afternoon…possibly because the air mass has been stabilized or because the outflow boundary weakens with time.

With that said, still expect some sort of boundary to enter the area by mid afternoon from the NW/N along with some dynamics from the short wave over OK (although the main thrust will be not our N and NE). This combined with strong heating and likely returning southerly flow and deeper moisture may set things off once again. Lack of strong well defined outflow boundaries at least initially will likely keep storms isolated to scattered. Based on the current trends, the seabreeze or returning offshore boundary, may be more of a driver today than anything coming from the NW. Much like yesterday the forecast is very uncertain as to when/if storms will develop and the locations that will see the greatest impacts.

As with the storms yesterday, damaging winds will be the main threats. Wind gust to 60-70mph will be possible under the strongest storms along with hail. Dead trees from the drought were heavily impacted by the strong winds yesterday and this will continue to be a concern with such trees falling on power lines and structures.

Should see less activity tomorrow into Friday as ridging briefly rebuilds over the area. Upper level trough develops over the northern Gulf coast this weekend and extends SW into coastal TX lowering the height field aloft. This will create favorable conditions for seabreeze convection this weekend into early next week mainly south of I-10 each afternoon. For now with throw in 20-30% south of I-10 for each day starting on Saturday.

Tropics:

Models continue their widely varying solutions of potential development in the Caribbean or Gulf of Mexico next week. With nothing currently in place and solutions different between each model and from run to run will need to keep an eye to the tropics for next week.

Tuesday Storm Reports:

A large severe thunderstorm developed along the leading edge of NE TX outflow boundary yesterday afternoon along I-45 near Conroe and moved southward to Downtown Houston. Widespread wind damage occurred from this storm in a corridor from Conroe to near Aldine. A total of 161,000 residents lost power mainly from falling trees on power lines. As of this morning 25,000 remain without power.

Conroe, Montgomery: Trees and street signs blown down. Traffic lights damaged. Trees into homes.

The Woodlands, Montgomery: Trees down across the road at Forestgate and Woodlands Pkwy

The Woodlands, Montgomery: Trees down at Rayford and Sawdust, large sign blown down onto a car, Est winds to 65mph

The Woodlands, Montgomery: Lightening strike caught garage on fire.

The Woodlands, Montgomery: Numerous trees down at Augusta Pines Golf Club, Research Forest Dr, Panther Creek Subdivision.

Spring, Harris: Large tree down through a brick wall west of I-45 near Spring Stuebner

Spring, Harris: street sign damaged at Richey Rd and I-45

Houston, Harris: 70mph wind at FM 1960 and Aldine Westfield. Numerous trees down. 52mph wind gust at BUSH IAH. 1.0 inch diameter hail at IAH.

Houston, Harris: Trees blown down on Cypresswood Dr near Spring High School.

Snook, Burleson: Trees down on CR 268 near Snook

Caldwell, Burleson: Trees down along FM 1362

North Harris County (note the blowing dust at the street level):

[Ed Lizard]

Drive home yesterday was awesome. Only about two tenths at the house (from HGX 88D storm totals and DWH obs), but wind gusts were near severe limits on I-45 South of BW8. Haven't seen 50 knot winds or wind gusts in almost 4 years, probably didn't break the streak yesterday, but it was close. Gust front before the rain had a couple swirls of dust and paper/debris, was keeping my eyes out for a gustnado, not to be.

Healthy cu development out my South facing window, South winds on the coast, near calm inland, radar showing storms on what is probably last night's OFB coming back, SPC meso page under -25 J/Kg CINH, near 2500 J/Kg MLCAPE in the morning, nearly -7ºC SBLI already, 1.6" PW. NAM sim radar at 3 hours underdone, but still shows local showers later.

Glass half full optimistic on rain for SETX.

Bonus feature, MCV on Red River almost has a tropical cyclonish look with lower cyclonic flow and anticyclonic cirrus outflow as seen on ICT centered ADD visible loop.

[yoda]

http://www.weather.g...story/KDFW.html

a

t

e Time

(cdt) Wind

(mph) Vis.

(mi.) Weather Sky Cond. Temperature (ºF) Relative

Humidity Wind

Chill

(°F) Heat

Index

(°F) Pressure Precipitation (in.) Air Dwpt 6 hour altimeter

(in) sea level

(mb) 1 hr 3 hr 6 hr Max. Min. 13 18:53 NW 17 1.00 Thunderstorm Heavy Small Hail/Snow Pellets Rain FEW020 BKN035CB OVC070 78 73 91 77 85% NA 80 29.87 1010.8 0.30 0.30

[Ian]

nice supercell over west dalas county now. reports of wall cloud etc.. tho it's being undercut by outflow for now.

[bubba hotep]

Very cool aternoon and evening across DFW today! No pictures but some of the most impressive cloud structure that I have ever seen in person. The back side of the 2nd Dallas supercell was wicked cool, like watching an aircraft carrier go across the deep blue sea with the sun setting behind it.

Edit to add some pics from the DFW area:

[Ian]

http://pix.myfoxdfw.com/Media/View/2410315

http://pix.myfoxdfw.com/Media/View/2410317

[Quixotic1]

Once again, people are trapped in traffic because of others blocking underpasses.

[Ed Lizard]

Dallas stuff was wrong place/wrong time. SPC MCD, IIRC, only gave a 20% chance of a watch issuance, and there were only 3 cells, but they just happened to catch population centers.

Unrelated, GFS at 192, before truncation, has a sloppy low South-Southeast of BRO, but happily, it is about to throw a big blob of rain into the Upper Texas Coast.

[Srain]

The storms that were in the Dallas area last night have drifted SE into E TX/LA with outflow boundaries to our N. HGX has issued a Flash Flood Warning in Houston County were 4+ inches of rain has fallen early this morning with a very strong thunderstorm. Strong storms continue to trek S in our Northern Counties mainly E of I-45 and that should continue the next couple of hours. Isolated showers/storms may be an issue during peak heating again today, so we'll monitor that potential. The GFS and Euro suggest the upper low associated with the morning showers/storms will drop S into the Gulf and drift Westward during the weekend keeping an unsettled pattern in place with daily scattered showers/storms across the Region. There remains some uncertainty regarding where and when this disturbance will track inland, but chances are a wet pattern will be ahead depending on which model is more correct.

The 00Z GFS and Euro both suggest a broad area of low pressure developing next week as the monsoonal trough lifts N and moisture and rainfall chances increase in the Bay of Campeche. The GFS is rather aggressive suggesting a meandering TS or Hurricane developing just E of Tampico while the Euro keeps the board low pressure a bit weaker, but also very slow to move. Meanwhile TS Carlotta has formed in the EPAC and is expected to become a Hurricane near the Gulf of Tehuantepec by Friday. Needless to say the tropics are showing signs of becoming active and eyes turn to the Western Caribbean/Gulf later this weekend.

[Ed Lizard]

Euro forecast would not being significant rain to my lawn. GFS would. But Euro is usually better.

I wish they had panned up to the see the awesome structure some more, but sweet wall cloud action from our friends at Texas Storm Chasers...

[Srain]

SPC:

...E TX/GULF CST TODAY THROUGH EARLY FRI...

COMBINATION OF VERY MOIST AIR /PW AROUND 1.75 INCHES/ AND PERIODIC

UPLIFT INVOF AFOREMENTIONED MCVS EXPECTED TO FOSTER A CONTINUING

RISK FOR STRONG TO OCCASIONALLY SVR TSTMS WITH HAIL AND LOCALLY DMGG

WIND FROM E TX E/SE ALONG THE CNTRL AND ERN GULF CST. WEAK DEEP

SHEAR WILL LIMIT STORM ORGANIZATION AND SUSTENANCE. AN EXCEPTION

WILL BE OVER E/SE TX AND WRN LA...WHERE 30 KT NWLY SHEAR MAY SUPPORT

A FEW LONGER-LIVED CELLS. WHILE ALL THE STORMS WILL BE DIURNALLY

ENHANCED...SPORADIC SVR ACTIVITY MAY PERSIST THROUGH EARLY FRI.

[bubba hotep]

Dallas stuff was wrong place/wrong time. SPC MCD, IIRC, only gave a 20% chance of a watch issuance, and there were only 3 cells, but they just happened to catch population centers.

And those cells were basically unexpected. I know there was no mention of storms in the morning FWD discussion and I don't believe there was any in the afternoon one either. There was an area of aggitated cumulus north of downtown that caught my eye when I left work. They really started to tower as I headed north on the train and by the time I reached my house you could see the base of the 1st super with a rain shaft. It was drifting east and looked like it would pass just south of us and then it really exploded and made a hard right turn as it ran south just to the east of 75. It was very cool to watch. Then as it moved south I could see the back side of the 2nd super while I was out on my run. Then a 3rd super formed to the north of us and that was wicked to watch as it raced south towards us. The coolest part was when it started hailing on me as I was running back up to my house but you could see that the rain shaft was still a mile or so away.

[Quixotic1]

And those cells were basically unexpected. I know there was no mention of storms in the morning FWD discussion and I don't believe there was any in the afternoon one either. There was an area of aggitated cumulus north of downtown that caught my eye when I left work. They really started to tower as I headed north on the train and by the time I reached my house you could see the base of the 1st super with a rain shaft. It was drifting east and looked like it would pass just south of us and then it really exploded and made a hard right turn as it ran south just to the east of 75. It was very cool to watch. Then as it moved south I could see the back side of the 2nd super while I was out on my run. Then a 3rd super formed to the north of us and that was wicked to watch as it raced south towards us. The coolest part was when it started hailing on me as I was running back up to my house but you could see that the rain shaft was still a mile or so away.

Irving/Dallas storm from Tarrant County view. My nephew took this pic. Looks like we weren't that far off from having bigger problems than hail:

[Srain]

HPC Afternoon Update re: Tropics...

CURRENT MJO IN PHASE 8 ENTERING PHASE 1 CONTINUES SHOWING

FAVORABLE VELOCITY POTENTAIL ANOMALIES AND H200 AND H850 OVER THE

EASTERN TROPICAL PACIFIC/ CENTRAL AMERICA AND THE WRN

CARRIBEAN/GLFMEX. BROAD SCALE ANOMALOUS H850 WESTERLY FLOW IN THE

TROPICAL EPAC SUPPORTS BROAD SCALE CYCLONIC CIRCULATION AIDING IN

POTENTIAL TROPICAL DEVELOPMENT ESPECIALLY EPAC AND TO A LESSER

EXTENT WRN CARIB AND LOWER GLFMEX. MOST OF THE MODELS HAVE BEEN

SHOWING VARIOUS FORMS OF TROPICAL DEVELOPMENT IN BOTH THE EPAC AND

WRN CARIB/LOWER GLFMEX BASINS AND EXPECT THAT SOME FORM OF

TROPICAL DVELOPMENT MAY OCCUR OR BEGIN TO OCCUR LATE PERIOD AND

THE FOLLOWING WEEK.

[Srain]

HGX afternoon update:

OVERALL WATER VAPOR CONTENT REMAINS ELEVATED OVER MOST OF THE

PERIOD AND...WITH THE MODELS DEVELOPING LOWER PRESSURES OVER THE

NORTHERN AND SOUTHERN GULF...EASTERLY FLOW STEERING THIS WAVE(S)

TOWARDS OUR COAST WILL KEEP SOUTHERN FA/MARINE LOWER-END CHANCE

POPS IN PLACE THROUGH MID-JUNE. THE ENSEMBLE TRENDS TOWARDS GENERALLY

WEAKER RIDGING...OR SOUTHEAST TEXAS EVENTUALLY FALLING WITHIN A

(HEIGHT) WEAKNESS CHANNEL. THIS MESHES WITH THE IDEA OF BRINGING A

NORTHERN GULF EASTERLY WAVE WESTWARD TOWARDS OUR COAST. NAM12 HAS

A BROAD CYCLONIC CIRCULATION MOVING INTO OUR WATERS SUNDAY. THE

GFS SOLUTION STILL DEVELOPS A LARGE SCALE CIRCULATION /WEAK SFC

LOW OVER THE BAY OF CAMPECHE FROM AROUND THURSDAY INTO NEXT WEEKEND

...CLOSED-OFF UPPER LOW BY NEXT WEEKEND. THE ECMWF ALSO PICKS UP

ON THESE LOWER SFC PRESSURES AND...ALBEIT MORE BROAD AND WEAK...DOES

MOVE THIS FEATURE UP THE MEXICO COAST THROUGH DAY 10. FWIW...THE

NOGAPS ALSO DEVELOPS A SFC LOW IN THE SOUTHERN BAY OF CAMPECHE AT

HR 144. ALL OF THIS TRANSLATES TO AN EARLY WEEK SOUTHEAST-TRANSITIONING

-TO-EASTERLY FETCH THAT WILL PUMP IN GULF MOISTURE INTO AN ALREADY

UNSTABLE ENVIRONMENT. IF THESE SOLUTIONS GAIN MORE CONSISTENCY IN

THE COMING DAYS THEN EXPECT A BAY OF CAMPECHE/SW GULF TROPICAL SYSTEM

WITHIN A WEEK AND HEIGHTENED SE TX RAIN/ISO STORM PROBABILITIES.