November: Cool & Dry To End The Month

[unome]

it sure doesn't look like the ULL is moving, but moisture is streaming into TX from the Pacific

loop http://cimss.ssec.wisc.edu/snaap/convin ... nframes=40

[redneckweather]

I sure hope this becomes a good solid rain maker with good cold air behind it....the good ol days so to speak. I do know that the air is now down right thick outside. Yack!!!

[srainhoutx]

If the 12Z WRF is correct, Tuesday will be the day to watch...

[srainhoutx]

LOL AZ. There are many a forecaster doing a double take right now. The pattern is throwing curve balls right and left. Now 80's are not that uncommon in mid November. If Dan was still alive and with us, he'd tell you the same thing. And just so you know AZ, no one, and I mean no one misses Dan more than I do. He was my long time bud and one of my best friends. No one misses those daily phone chats more than I do. Trust me on that one...

[biggerbyte]

Everything is getting pushed back. What looked like a Monday event has transitioned into overnight into Tuesday. Everything should be done by nightfall.

[Ptarmigan]

Everything is getting pushed back. What looked like a Monday event has transitioned into overnight into Tuesday. Everything should be done by nightfall.

Should be an interesting night. Another middle of the night storm?

[biggerbyte]

Sometime overnight into Tuesday afternoon. Middle of the night is most likely too soon for this event to
move out.

[srainhoutx]

HGX seems to think Tuesday will be the day to watch locally. The Euro solution hints severe weather may be a possibility, but I'd like to see this system get fully onshore in the Baja Region before biting off on any solution two days out. That said, Austin/San Antonio almost pulled the trigger on Flash Flood Advisory/Watches, but decided a Special Weather Statement would be the best way to handle things today. Should the trends continue for widespread 1-2 inch rainfalls in our area, HGX may consider doing the same tomorrow. We will see...

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
352 PM CST SUN NOV 13 2011

TXZ171>173-183>194-202>209-217>225-228-140300-
LLANO-BURNET-WILLIAMSON-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-
GILLESPIE-KENDALL-BLANCO-HAYS-TRAVIS-BASTROP-LEE-KINNEY-UVALDE-
MEDINA-BEXAR-COMAL-GUADALUPE-CALDWELL-FAYETTE-MAVERICK-ZAVALA-
FRIO-ATASCOSA-WILSON-KARNES-GONZALES-DE WITT-LAVACA-DIMMIT-
INCLUDING THE CITIES OF...LLANO...BURNET...GEORGETOWN...DEL RIO...
ROCKSPRINGS...LEAKEY...KERRVILLE...BANDERA...FREDERICKSBURG...
BOERNE...BLANCO...SAN MARCOS...AUSTIN...BASTROP...GIDDINGS...
BRACKETTVILLE...UVALDE...HONDO...SAN ANTONIO...NEW BRAUNFELS...
SEGUIN...LOCKHART...LA GRANGE...EAGLE PASS...CRYSTAL CITY...
PEARSALL...PLEASANTON...FLORESVILLE...KARNES CITY...GONZALES...
CUERO...HALLETTSVILLE...CARRIZO SPRINGS
352 PM CST SUN NOV 13 2011

...MUCH NEEDED RAINFALL LIKELY MONDAY NIGHT THROUGH TUESDAY...

AN UPPER LEVEL STORM SYSTEM CURRENTLY OFFSHORE OF THE BAJA OF
MEXICO WILL MOVE EAST ACROSS SOUTH CENTRAL TEXAS LATE MONDAY NIGHT
THROUGH TUESDAY. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
WILL DEVELOP LATE MONDAY NIGHT ACROSS WESTERN PORTIONS OF THE AREA
AND TRANSITION EAST TO THE INTERSTATE 35 CORRIDOR TUESDAY MORNING...
THEN CONTINUE EAST OUT OF SOUTH CENTRAL TEXAS TUESDAY AFTERNOON.

STORM TOTAL RAINFALL AMOUNTS WILL RANGE FROM ONE TO TWO INCHES
WITH HEAVY DOWNPOURS AFFECTING MUCH OF THE AREA. IN ADDITION...A
FEW STORMS MAY APPROACH SEVERE LEVELS.

[Portastorm]

Yeah, EWX said with the ongoing drought they were a bit reluctant to pull the trigger on a FFA.

[srainhoutx]

Guidance continues to struggle with the timing of the upper low nearing the Baja Region, but enough agreement is in place that a potential exists for a severe weather episode that the SPC has placed most of SE TX in a Slight Risk for Tuesday. While the parameter are not that strong, the risk for tornadoes with strong down bursts appears to be the biggest threat. While heavy rainfall has diminished somewhat due to the progressive nature of the upper disturbance and capping ahead of that feature, there remains enough uncertainty to warrant caution of quick heavy rainfall if caught under any thunderstorms that do develop. Soundings indicate a cap will be in place today, but I wouldn't be surprise to see streamer showers begin to develop as the day goes on. Breaks in the clouds should allow the low 80's to be again reached today. We'll need to keep on eye to our W this evening to see if a meso convective system develops. Longer range suggests we'll do it all again in the coming weekend as yet another upper disturbance/trough develops to our W.

[srainhoutx]

For what it's worth, the 12z WRF develops a MCS (meso convection system) over Central TX tomorrow and shifts it E. We will see...

[srainhoutx]

For what it's worth, the 12z WRF develops a MCS (meso convection system) over Central TX tomorrow and shifts it E. We will see...

Fairly good agreement from the 12Z GFS...

[wxman666]

The microcast David Paul showed this morning has the bullseye over my region and NWS HGX says it looks like the most favorable conditions will be NW of Houston so I'm a little on edge.

[srainhoutx]

SPC expands Slight Risk with latest update:

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1130 AM CST MON NOV 14 2011

VALID 151200Z - 161200Z

...THERE IS A SLGT RISK OF SVR TSTMS TUE AND TUE NIGHT ACROSS PARTS
OF SOUTHEAST TEXAS INTO THE LWR MISSISSIPPI VALLEY...

...SYNOPSIS...
WITHIN THE GENERALLY ZONAL STRONGER BELT OF WESTERLIES EXTENDING
ACROSS THE NORTHERN TWO-THIRDS OF THE U.S...BROAD UPPER TROUGHING
APPEARS LIKELY TO REMAIN PROMINENT ACROSS THE NORTH CENTRAL STATES
THROUGH THIS PERIOD. WITHIN THIS REGIME ANOTHER SIGNIFICANT SHORT
WAVE IMPULSE IS EXPECTED TO DIG INTO THE NORTHERN PLAINS BY EARLY
TUESDAY...BEFORE TURNING EASTWARD THROUGH THE UPPER MIDWEST. AS
THIS OCCURS...A REINFORCING COLD INTRUSION IS PROGGED TO THE LEE OF
THE ROCKIES. WHILE THE PRIMARY SURFACE CYCLONE EVOLVES ACROSS AND
NORTHEAST OF THE UPPER GREAT LAKES REGION...MODELS INDICATE WEAK
SURFACE WAVE DEVELOPMENT WILL OCCUR ALONG THE FRONT ACROSS THE
SOUTHERN PLAINS INTO UPPER PORTIONS OF THE LOWER MISSISSIPPI VALLEY
BY LATE TUESDAY EVENING. THIS IS EXPECTED TO OCCUR IN RESPONSE TO
THE NORTHEASTWARD ACCELERATION OF A CLOSED LOW/UPPER TROUGH OUT OF
THE MEXICAN PLATEAU. THE UPPER IMPULSE PROBABLY WILL WEAKEN WITHIN
THE CONFLUENT REGIME TO THE NORTHWEST OF A SUBTROPICAL RIDGE...WHICH
MAY BE SLOW TO LOSE ITS INFLUENCE ON THE EASTERN GULF AND SOUTH
ATLANTIC COAST STATES.

AHEAD OF THE SOUTHEASTWARD ADVANCING COLD FRONT...AND GENERALLY
ALONG AND SOUTH OF THE REMNANTS OF A WEAKENING/STALLING FRONT
CURRENTLY EXTENDING ACROSS THE SOUTHERN PLAINS/MIDDLE MISSISSIPPI
AND OHIO VALLEYS...AN INFLUX OF MOISTURE SHOULD CONTINUE OFF THE
WESTERN GULF OF MEXICO. THIS IS EXPECTED TO CONTRIBUTE TO
SUFFICIENT DESTABILIZATION TO SUPPORT THE RISK FOR THUNDERSTORM
ACTIVITY...FROM THE WESTERN GULF COAST STATES NORTHEASTWARD INTO
PARTS OF THE LOWER OHIO AND TENNESSEE VALLEYS. AT LEAST SOME
POTENTIAL EXISTS FOR THE DEVELOPMENT OF A FEW SEVERE STORMS...
MAINLY ACROSS SOUTHEASTERN TEXAS INTO PARTS OF THE LOWER MISSISSIPPI
VALLEY.

...SOUTHEAST TEXAS INTO THE LOWER MISSISSIPPI VALLEY...
AHEAD OF THE SOUTHERN IMPULSE...CONVECTIVE POTENTIAL COULD BE
ENHANCED SOMEWHAT BY AT LEAST MODEST MID-LEVEL LAPSE RATES. WITH
SURFACE HEATING...MODELS INDICATE MIXED LAYER CAPE ON THE ORDER OF
500 TO 1000 J/KG TUESDAY AFTERNOON...AS A 60-70 KT SOUTHWESTERLY 500
MB JET STREAK NOSES OUT OF THE LOWER RIO GRANDE VALLEY TOWARD THE
CENTRAL GULF COAST. COUPLING OF THIS SPEED MAXIMUM WITH A BROAD
DOWNSTREAM SOUTHWESTERLY MID/UPPER JET ...TO THE NORTH OF THE
SUBTROPICAL RIDGE...IS EXPECTED TO CONTRIBUTE TO CONSIDERABLE
THUNDERSTORM ACTIVITY. IN THE PRESENCE OF STRONG DEEP LAYER
SHEAR...ORGANIZED CONVECTIVE CLUSTERS AND ISOLATED SUPERCELLS WILL
BE POSSIBLE...WITH POTENTIAL FOR AT LEAST LARGE HAIL AND LOCALIZED
DAMAGING WIND GUSTS. UNCERTAINTY EXISTS CONCERNING THE STRENGTH OF
THE LOW-LEVEL FLOW FIELDS AND SHEAR...DUE TO THE RELATIVELY WEAK
NATURE OF THE FRONTAL WAVE...WHICH COULD LIMIT TORNADIC AND BROADER
SCALE DAMAGING WIND POTENTIAL.

THE STRONGER MID-LEVEL HEIGHT FALLS ASSOCIATED WITH THE SOUTHERN
IMPULSE COULD FOCUS ONE CORRIDOR OF SEVERE WEATHER POTENTIAL ACROSS
SOUTH CENTRAL AND SOUTHEAST TEXAS DURING THE DAY TUESDAY...PERHAPS
INTO PARTS OF LOUISIANA AND MISSISSIPPI TUESDAY NIGHT. ANOTHER
CORRIDOR COULD EVOLVE IN CLOSER PROXIMITY TO THE DEVELOPING FRONTAL
WAVE...ACROSS PARTS OF THE ARKLATEX THROUGH SOUTHEASTERN ARKANSAS
AND PARTS OF WESTERN TENNESSEE/NORTHERN MISSISSIPPI...LATE TUESDAY
AFTERNOON INTO TUESDAY NIGHT...WHERE/ WHEN POTENTIAL FOR THE
DEVELOPMENT OF LARGER LOW-LEVEL HODOGRAPHS SEEMS BEST.

..KERR.. 11/14/2011

[srainhoutx]

The models are all (NAM, GFS, Euro, Ukmet & Canadian) in agreement with timing and strength of the upper low currently onshore in Mexico, E of the Baja. Now we wait and see if things pan out as expected and perhaps monitor the shorter range meso models (HRRR, SREF, RUC) for any subtle changes.

[srainhoutx]

Afternoon e-mail from Jeff:

Widespread rainfall and some severe weather likely on Tuesday

Powerful upper level storm system over NW MX today is starting to move eastward this afternoon with downstream moisture advection in progress over TX from both the Gulf and the Pacific. Increasing low level moisture below the capping inversion in the mid levels is supporting isolated showers along and south of I-10 west of Katy or over the counties of Fort Bend, Brazoria, Matagorda, Wharton, Jackson, and Calhoun currently. Capping should limit overall intensity and coverage of these showers today.

Main event slated for Tuesday as potent upper level storm moves across TX. Large scale lift will come to bear across the region along with favorable jet stream positions and mid level cooling. Low level moisture surges early Tuesday with PWS rising into the 1.6-1.8 in range or nearly 150% of normal for mid November. Combination of cooling with the storm system in the mid levels and strong lift will help erode the mid level cap and expect numerous showers and thunderstorms to develop starting Tuesday morning and lasting into the afternoon hours.

Overall severe threat is expected to mainly be large hail and damaging winds, but a tornado threat does exist over the upper TX coastal plain Tuesday. Marginal surface heating will likely support early afternoon CAPE values of 500-1200J/Kg over SE TX amidst steepening lapse rates yielding an increasingly unstable low level air mass. 60-80kt jet streak noses into the upper TX coast from the southwest out of NE MX during the early afternoon hours and this should help support overall thunderstorm development and increasing intensity. While low level winds fields are backed to a degree, the intensity of the low level shear over SE TX remains questionable and this fact is currently mitigating a greater tornado threat. Should stronger low level wind fields and shear be realized over the region a greater tornado threat will be in place. At this time large hail appears to be the main severe mode.

A combination of linear lines and clusters along with a few isolated low topped supercells look possible on Tuesday. Favorable Gulf inflow and potential for cell training will yield some decent rainfall totals in SW to NE corridors across the region as the air mass nears saturation just ahead of the upper level impulse. Expect numerous thunderstorms to develop and move from SW to NE across the area with widespread rainfall amounts of .5 -1.5 inches and isolated amounts of 2-3 inches under the stronger cells or where cell training develops. Progressive nature of the entire system along with dry ground conditions should help mitigate the flash flood threat. This system looks to get everyone east of I-35 wet!

Dry conditions will be in place Wednesday-Friday with high pressure in control. Next upper level storms digs into the SW US this weekend, but the potential ejection eastward of this system appears more toward the central plains than TX as downstream sub-tropical ridging builds NW into the TX coast from the Gulf.

[unome]

backing off on rain totals

00Z http://www.hpc.ncep.noaa.gov/qpf/p120i00.gif

12Z http://www.hpc.ncep.noaa.gov/qpf/p120i12.gif

[redneckweather]

We will get a sprinkle out of this (maybe) but don't look for any drought relief. Ain't happening.

[wxman666]

Lol, I love how everyone gets excited, then pessimistic then exited again. Folks, look at NWS and SPC. We're wide open. I see 80% thunderstorms, some severe with heavy rain in HGX's forecast. Furthermore, the SPC has the entire CWA in a slight risk. Don't model hug. They're notorious for flip flopping. Remember last Tuesday? We weren't so confident once the time came around but we ended up getting tornadoes in parts of the area.

[srainhoutx]

Just the calm before the 'storm'. I'm sure you 'night owls' will be watching carefully...