Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 7

[Roy]

Latest Tech WRF appears to hang the front back slightly, about an hour slower through DFW, so that may help eastern areas to get something. Will have to see what does verify today.

[cstrunk]

We've had much more sunshine today than I expected in Tyler. Instability is building nicely, we have 35-40 kt effective bulk shear in the area, and 100-200 m2/s2 effective helicity.  Showers and thunderstorms are beginning to build just to the north and west.  I'm expecting severe thunderstorms with an outside chance at a couple tornadoes in the NE TX area.

[jhamps10]

I'm stsrting to think the lack of Water at lake granbury and possum kingdom is really effecting storm development chances in ft worth... Seems like EVERY time we either get capped or they develop east of us... Every system that's a bust is one day closer to summer with no rain... This is NOT good!

[Roy]

Yeah nothing is really towering yet. There was a glimmer of hope for parts of FW this morning...it wouldn't surprise me if lake levels do impact things to some degree. We need rain badly.

[Quixotic1]

Yeah nothing is really towering yet. There was a glimmer of hope for parts of FW this morning...it wouldn't surprise me if lake levels do impact things to some degree. We need rain badly.

 

The drought elsewhere and the NW flow have killed us but the lack of tropical activity in the summer hasn't helped.  We used to get easterly waves now and then, but it's been a long while since we've had one of note.      

[NTXYankee]

Well at least folks in DFW can start counting how many times this severe weather season we have a boundary knocking on our door that produces nothing....  Sad

[jhamps10]

Well at least folks in DFW can start counting how many times this severe weather season we have a boundary knocking on our door that produces nothing.... Sad

Just as annoying as our winter was.... So much for El Niño helping us out... Ugh....

[bubba hotep]

Still holding out hope that MBY can score something. Front is still pretty far to the NW but not seeing anything in the sky or radar indicating that storms are about to go up.

Edit: and just like that storms firing along cold front west of DFW

[vwgrrc]

Well at least folks in DFW can start counting how many times this severe weather season we have a boundary knocking on our door that produces nothing.... Sad

exactly like our winter

[aggiegeog]

Storming pretty good around here, nothing severe yet though.

 

Still holding out hope that MBY can score something. Front is still pretty far to the NW but not seeing anything in the sky or radar indicating that storms are about to go up.

Edit: and just like that storms firing along cold front west of DFW

 A line is trying to form NW of the Metroplex.

[Quixotic1]

If you're a fan of historic DFW area tornadoes, you'll love the possible scenario described in the FWD AFD.

 

Paris and Lancaster tornadoes were mentioned.  

 

ETA:  This is for Monday.  

[jhamps10]

Still holding out hope that MBY can score something. Front is still pretty far to the NW but not seeing anything in the sky or radar indicating that storms are about to go up.

Edit: and just like that storms firing along cold front west of DFW

Yeah your back yard like the rest of north Texas east of 35e... STOP HOGGING THE RAIN WHY DONt Ya lol

At this point the only thing saving Tarrant county from a major water disaster would be a hurricane... We aren't as bad as Wichita falls but we're dang close...

[jhamps10]

If you're a fan of historic DFW area tornadoes, you'll love the possible scenario described in the FWD AFD.

Paris and Lancaster tornadoes were mentioned.

ETA: This is for Monday.

Heh I was gonna say how would we get a tornado out of this today... Hail and straight line winds sure but don't see any twisting for dfw proper

[Quixotic1]

Heh I was gonna say how would we get a tornado out of this today... Hail and straight line winds sure but don't see any twisting for dfw proper

 

No, the lower level shear isn't there.  Not sure we're going to see anything at all.  that line started well but might be getting cutoff from the storms to the south.  

[Quixotic1]

No, the lower level shear isn't there.  Not sure we're going to see anything at all.  that line started well but might be getting cutoff from the storms to the south.

Annnnd it's going to split me. Great googly moogly.

[bubba hotep]

Some very healthy looking towers going up along the cold front.

[Roy]

Well that happened quick. Some towering when I left to go to an appointment at 4, but radar echoes were extremely light. Then, it explodes quickly. Been raining hard for a good 15-20 minutes now in North Fort Worth. Nothing severe, but we need some stinking heavy rain, so I will take it. Sky starting to lighten so likely ending soon.

[jhamps10]

Annnnd it's going to split me. Great googly moogly.

Welcome to my world....

[jhamps10]

Well that happened quick. Some towering when I left to go to an appointment at 4, but radar echoes were extremely light. Then, it explodes quickly. Been raining hard for a good 15-20 minutes now in North Fort Worth. Nothing severe, but we need some stinking heavy rain, so I will take it. Sky starting to lighten so likely ending soon.

Would have been nice to have gotten that on the sw side of town, not a single drop down here by hulen mall

[bubba hotep]

Was thinking we might see things unzip all along the front but have seen nothing but false starts to the NE of the warned cell.

[Roy]

Really surprised to not be seeing more cells considering how fast that one went up.

[cstrunk]

We've had much more sunshine today than I expected in Tyler. Instability is building nicely, we have 35-40 kt effective bulk shear in the area, and 100-200 m2/s2 effective helicity.  Showers and thunderstorms are beginning to build just to the north and west.  I'm expecting severe thunderstorms with an outside chance at a couple tornadoes in the NE TX area.

 

Had our first tornado warning in the area issued for southern Smith County/Northern Cherokee county here in NE TX.  I don't think it was anything substantial but the storm had a nice area of rotation.  Might have spun up something very briefly.  Will have to watch the southern ends of these storms as they move east.

 

Here in Tyler we've had a lot of heavy rain and lightning, which has been very refreshing to see for once!

[radarman]

Would have been nice to have gotten that on the sw side of town, not a single drop down here by hulen mall

Yeah I am right there too... we might have got a few drops lol.

Once the SVR went up for much of Arlington, Grand Prairie and the like the cell fell apart quickly. Had a really sloppy radar presentation.

[cstrunk]

New tornado warnings for Gregg County (Longview) and Rusk County (New London).

[NTXYankee]

If you're a fan of historic DFW area tornadoes, you'll love the possible scenario described in the FWD AFD.

 

Paris and Lancaster tornadoes were mentioned.  

 

ETA:  This is for Monday.  

Oh lord, I read the AFD and thankfully they are not talking up an outbreak.  Personally the heavy rain event is more likely and what is probably even more likely is the boundary will be way up in Oklahoma by the time Monday comes around and there will be numerous storms south of DFW and North Texas blocking any moisture from working it's way up to us so we miss out on another good rain event...

[Disc]

Longview, TX

 

[Quixotic1]

You guys in East Texas think you're so superior with your high CAPEs and impeccable timing.

[Roy]

Of course, NTX.

[bubba hotep]

Bam!

 

000
FXUS64 KFWD 092054
AFDFWD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
354 PM CDT THU APR 9 2015

.SHORT TERM...

THROUGH TONIGHT...THE PRIMARY FORECAST CONCERN IS THUNDERSTORM
CHANCES AND ASSOCIATED SEVERE WEATHER EXPECTATIONS FOR NORTH AND
CENTRAL TEXAS.

AT 3 PM CDT A COLD FRONT WAS LOCATED ALONG A LINE FROM GAINESVILLE
TO CISCO...MOVING SOUTHEAST TOWARDS THE DFW METROPLEX. FARTHER TO
THE SOUTHEAST...A PERSISTENT LOW-LEVEL WARM AIR ADVECTION REGIME
RESULTED IN THE INITIATION OF SCATTERED THUNDERSTORMS FROM WACO
NORTHEAST TO TERRELL AND EAST TOWARDS PALESTINE. LOCAL CONVECTIVE
PARAMETERS INDICATE THAT SURFACE BASED CONVECTION IS ONLY CAPPED
BY 50 J/KG OF INHIBITION OR LESS FOR MOST LOCATIONS SOUTHEAST OF
THE COLD FRONT. AS A RESULT...THERE IS A CHANCE THAT ANY
THUNDERSTORM ACTIVITY THAT DEVELOPS WILL BECOME SURFACE BASED
THROUGH SUNSET.

SURFACE BASED CONVECTION HAS ANYWHERE FROM 1500 TO 2500 J/KG OF
AVAILABLE ENERGY FOR UPDRAFT GROWTH (CAPE)...WHICH IS CERTAINLY
ENOUGH TO SUPPORT STORMS STRONG ENOUGH TO PRODUCE SEVERE WEATHER
IMPACTS. DEEP LAYER SHEAR OVER THE REGION WAS ON THE ORDER OF 30
TO 35 KTS IN THE 0-6 KM LAYER...WHICH IS ON THE LOW END OF WHAT IS
TYPICALLY CONSIDERED SUFFICIENT FOR SUPERCELLS/ROTATING UPDRAFTS.
LOW-LEVEL WIND PROFILES ARE CHARACTERIZED BY 0-1 KM HELICITY
VALUES OF LESS THAN 50 M2/S2 WHICH IS NOT VERY SUPPORTIVE OF LOW-
LEVEL UPDRAFT ROTATION. AS A RESULT...THE TORNADO POTENTIAL FOR
MOST OF THE CWA APPEARS TO BE LOW AT THIS TIME. THIS IS MAINLY DUE
TO VEERED LOW-LEVEL WINDS ASSOCIATED WITH A PREFRONTAL TROUGH OUT
AHEAD OF THE COLD FRONT. THESE VEERED WINDS EXTEND TO A LINE FROM
APPROXIMATELY ATHENS TO TEMPLE. ALONG AND SOUTHEAST OF AN ATHENS
TO TEMPLE LINE...SURFACE WINDS ARE BACKED...RESULTING IN A LOW-
LEVEL SHEAR PROFILE MORE SUPPORTIVE OF LOW-LEVEL ROTATING UPDRAFTS
AND A TORNADO POTENTIAL. WILL BE WATCHING THIS AREA CLOSELY FOR AN
ENHANCED SUPERCELL/TORNADO POTENTIAL THROUGH SUNSET AS A RESULT.

EXPECT THAT STORMS WILL DEVELOP ALONG THE COLD FRONT BEFORE
SUNSET...WHICH WOULD BE IN ADDITION TO THE STORMS THAT WERE
ALREADY DEVELOPING IN THE WARM AIR ADVECTION REGIME WELL SOUTHEAST
OF THE FRONT. INITIALLY ELEVATED THUNDERSTORMS WILL LIKELY BECOME
SURFACE BASED AS UPDRAFTS PERSIST AND EVENTUALLY INGEST THE FAIRLY
UNSTABLE AIR LOCATED BELOW THE NOW WEAK CAPPING INVERSION ALOFT.
THE INITIAL STORM MODE MAY BE DISCRETE SUPERCELLS ONCE STORMS
TRANSITION TO SURFACE BASED...HOWEVER THIS STORM MODE IS NOT
EXPECTED TO LAST LONG. SOMEWHAT MARGINAL DEEP LAYER SHEAR WILL
LIKELY NOT BE ENOUGH TO KEEP COLD POOLS SEPARATED...AND COOL
OUTFLOW MERGERS AND UPSCALE GROWTH INTO MULTI-CELL CLUSTERS OR A
QLCS IS LIKELY. THE PRIMARY HAZARDS ASSOCIATED WITH ORGANIZED
STORMS THROUGH THIS EVENING ARE LARGE HAIL AND DAMAGING WINDS. THE
ONLY DIFFERENCE IN THREAT FOR SUPERCELLS COMPARED TO MULTI-CELLS
IS THAT THE HAIL WILL TEND TO BE LARGE IN SUPERCELL STORMS. THE
TORNADO THREAT FOR MOST LOCATIONS IS LOW...BUT WE WILL KEEP A
CLOSE EYE ON ANY SURFACE BASED STORMS NEAR THE SMALL PORTION OF
THE SOUTHEASTERN CWA WHERE LOW-LEVEL WINDS ARE BACKED AROUND TO
THE SSE.

THE COLD FRONT IS EXPECTED TO ADVANCE SOUTH ACROSS CENTRAL TEXAS
OVERNIGHT. THUNDERSTORMS SHOULD DIMINISH IN INTENSITY AND COVERAGE
AS THE FRONT CONTINUES SOUTH TONIGHT. COOLER AND DRIER AIR IS
EXPECTED TO BUILD ACROSS THE CWA BY FRIDAY MORNING BEHIND THE COLD
FRONT.

&&

.LONG TERM...

FRIDAY THROUGH SUNDAY...THE COLD FRONT IS EXPECTED TO SINK SOUTH
TOWARDS THE TEXAS GULF COAST ON FRIDAY...LEAVING THE CWA IN A
RELATIVELY COOL AND DRIER AIRMASS FOR MUCH OF THE DAY ON FRIDAY.
ANOTHER UPPER LEVEL STORM SYSTEM...EMBEDDED WITHIN THE
SUBTROPICAL JET...WILL BE APPROACHING THE REGION THIS WEEKEND. THE
FLOW ALOFT COMING OFF OF THE HIGH TERRAIN THE SOUTHERN CONUS AND
NORTHERN MEXICO WILL RESULT IN LEE SIDE TROUGHING OVER THE
SOUTHERN HIGH PLAINS BY FRIDAY AFTERNOON. THIS WILL INITIATE A
QUICK RESPONSE TO SOUTHERLY FLOW ALOFT OVER THE SHALLOW COLD
FRONTAL INVERSION BY FRIDAY AFTERNOON. DO NOT EXPECT MUCH IN THE
WAY OF PRECIPITATION/STORMS OVER NORTH OR CENTRAL TEXAS ON FRIDAY
AS IT WILL TAKE THIS SOUTHERLY FLOW ALOFT SOME TIME TO ADVECT RICH
GULF MOISTURE BACK OVER THE CWA. DID MAINTAIN SOME 20 POPS OVER
THE SOUTHERN CWA FRIDAY AFTERNOON HOWEVER TO ACCOUNT FOR THE
WARM/MOIST ASCENT OVER THE FRONTAL INVERSION.

SATURDAY AND SUNDAY...THE LEE SIDE TROUGH AND APPROACHING UPPER
LEVEL STORM SYSTEM WILL WORK IN TANDEM TO KEEP PERSISTENT MOIST
ASCENT OVER NORTH AND CENTRAL TEXAS THROUGH THE WEEKEND. FORECAST
SOUNDINGS INDICATE THAT THIS MAY RESULT IN SCATTERED ELEVATED
THUNDERSTORMS ACROSS THE CWA DURING THE DAY ON SATURDAY. THE AREAS
MOST LIKELY TO SEE THUNDERSTORMS ARE THOSE WEST OF INTERSTATE 35
AND SOUTH OF INTERSTATE 20 WHERE THE WARM/MOIST ADVECTION REGIME
IS FORECAST TO BE STRONGEST IN MODEL MASS FIELDS. THIS PERSISTENT
LIFT SPREADS NORTH AND EAST DURING THE DAY ON SUNDAY...MAKING
SCATTERED STORMS MORE LIKELY ACROSS THE ENTIRE CWA BY SUNDAY
AFTERNOON.

WITHOUT A WELL-DEFINED FRONT...EXPECT MOST THUNDERSTORM ACTIVITY
TO BE HIT AND MISS THIS WEEKEND...WITH THE GREATEST COVERAGE OF
STORMS STARTING OFF SOUTHWEST ON SATURDAY...AND EXPANDING NORTH
AND EAST ON SUNDAY. SEVERE WEATHER ON SATURDAY APPEARS TO BE
UNLIKELY BECAUSE STORMS ARE EXPECTED TO REMAIN ELEVATED IN NATURE.
SEVERE WEATHER CHANCES INCREASE ON SUNDAY AS PERSISTENT WARM/MOIST
ADVECTION MAY RESULT IN SOME NEAR SURFACE BASED STORMS. THINK THAT
WIDESPREAD CLOUD COVER WILL TEND TO LIMIT POTENTIAL INSTABILITY
THROUGH...SO THINK THAT MOST STORMS WILL REMAIN SUB-SEVERE ON
SUNDAY.

MONDAY...THE UPPER LEVEL STORM SYSTEM EMBEDDED IN THE SUB-TROPICAL
JET IS EXPECTED TO MOVE OVER THE SOUTHERN HIGH PLAINS ON MONDAY
WHILE BECOMING CUT OFF COMPLETELY FROM THE MUCH FASTER POLAR JET
STREAM TO THE NORTH. MOST MODEL GUIDANCE IS IN LINE WITH THIS
EVOLUTION FOR THIS UPPER LEVEL STORM SYSTEM...SO CONFIDENCE IS
FAIRLY HIGH IN THIS GENERAL PATTERN TAKING SHAPE. WITH A LARGE
UPPER TROUGH TO OUR WEST...AND A VERY WARM AND MOIST LOW-LEVEL AIR
MASS IN PLACE ACROSS THE REGION...THIS IS SYNOPTICALLY A VERY GOOD
SET UP FOR THUNDERSTORM CHANCES ACROSS THE CWA ON MONDAY.

THE CIPS ANALOG GUIDANCE PAGE HOSTED BY ST. LOUIS UNIVERSITY
INDICATES THAT THIS SYNOPTIC PATTERN IS SIMILAR IN PLACEMENT AND
DYNAMIC STRENGTH TO STORM SYSTEMS THAT HAVE HISTORICALLY RESULTED
IN HIGH IMPACT SEVERE WEATHER OUTBREAKS ACROSS NORTH OR CENTRAL
TEXAS. MODEL GUIDANCE INDICATES THAT A STATIONARY FRONT WILL LINE
UP JUST NORTH OF THE INTERSTATE 20 CORRIDOR ON MONDAY...WITH THE
SUBTROPICAL JET LOCATED OVER THE CWA WITHIN THE BASE OF THIS CUT-
OFF UPPER LOW TO OUR WEST. THIS WOULD SET UP A FAVORABLE
ENVIRONMENT FOR STRONG SHEAR OVER THE CWA WHICH COULD POTENTIALLY
BE SUPPORTIVE OF SUPERCELLS. THE PRIMARY LIMITING FACTOR FOR
SEVERE STORMS APPEARS TO BE THE EXTENT OF CLOUD COVER AND RAIN
SOUTH OF THE STATIONARY FRONT DURING THE DAY ON MONDAY. HERE ARE A
COUPLE OF SCENARIOS...ASSUMING THAT THE LARGE SCALE SYNOPTIC
PATTERN WILL HAPPEN AS ADVERTISED (WHICH IS NEVER 100 PERCENT
CERTAIN 4-5 DAYS OUT):

1. WIDESPREAD RAIN SHOWER AND THUNDERSTORM ACTIVITY OCCURS ALL
ALONG AND OUT AHEAD OF THE STATIONARY BOUNDARY. THIS APPEARS TO BE
THE MOST LIKELY SCENARIO TO PAN OUT AS ALL MODEL GUIDANCE FAVORS
THIS SOLUTION AT THIS TIME. THIS WOULD LIMIT HEATING WHICH WOULD
LIMIT POTENTIAL INSTABILITY FOR STRONG/SEVERE STORMS MONDAY
AFTERNOON. WHILE THIS LIMITS THE SEVERE WEATHER POTENTIAL BY
REDUCING LAPSE RATES FROM THE SURFACE TO THE TROPOPAUSE...THIS
ALSO RESULTS IN A DEEPER MOIST LAYER IN PLACE OVER THE CWA. THIS
SYNOPTIC SET UP SEEMS VERY FAVORABLE FOR HEAVY RAINFALL AND
POTENTIALLY FLOODING...ESPECIALLY NEAR THE STATIONARY BOUNDARY. IF
THE STATIONARY BOUNDARY DOES WIND UP OVER THE DFW METROPLEX...
THERE WOULD BE A PRETTY GOOD THREAT FOR FLASH FLOODING FROM MONDAY
MORNING THROUGH MONDAY NIGHT. THIS IS WHAT WE ARE GOING WITH IN
THE CURRENT FORECAST. NO FLOOD WATCHES WILL BE ISSUED AT THIS TIME
BECAUSE A LOT CAN CHANGE IN 4-5 DAYS...BUT THE POTENTIAL FOR
FLOODING WILL REMAIN A PRIMARY CONCERN AS WE HEAD THROUGH THE
WEEKEND INTO MONDAY.

2. IF CLOUDS ARE ABLE TO SCATTER OUT SOUTH OF THE FRONT...AND
THERE IS LITTLE TO NO RAINFALL SOUTH OF THE STATIONARY BOUNDARY ON
MONDAY...CONDITIONS WOULD SEEM TO BECOME MUCH MORE SUPPORTIVE FOR
A LOCAL SEVERE WEATHER EVENT. SOME OF THE ANALOGS THAT THE CIPS
ALGORITHM CAME UP WITH WERE THE PARIS AND LANCASTER TORNADO
EVENTS...SO THE LARGE SCALE ENVIRONMENT COULD CERTAINLY SUPPORT
SUPERCELLS THAT MAY PRODUCE TORNADOES. HOWEVER...THE ANALOG PAGE
IS JUST THAT...STATISTICALLY COMPARING LARGE SCALE PARAMETERS TO
WHAT MEDIUM RANGE GUIDANCE IS INDICATING FOR MONDAY. SINCE ALL
AVAILABLE GUIDANCE INDICATES THAT WE WILL REMAIN CLOUDY WITH
SCATTERED SHOWERS AND THUNDERSTORMS SOUTH OF THE STATIONARY
FRONT...THIS SCENARIO APPEARS UNLIKELY TO PAN OUT AT THIS TIME.

NEEDLESS TO SAY...IT LOOKS LIKE MONDAY IS A FAVORABLE DAY FOR HIGH
IMPACT WEATHER ACROSS PORTIONS OF NORTH AND CENTRAL TEXAS. IT
APPEARS THAT THE MOST LIKELY HAZARD WILL BE HEAVY RAINFALL AND
FLOODING...BUT WE WILL KEEP A VERY CLOSE EYE ON THE EVOLUTION OF
THIS SYSTEM JUST IN CASE SCENARIO 2 LOOKS MORE LIKELY IN THE
FUTURE.

REMAINDER OF THE WEEK...WE REMAIN IN A FAIRLY WET AND UNSETTLED
WEATHER PATTERN FOR THE WEEK AHEAD. MAINTAINED A LOW CHANCE OF
THUNDERSTORMS EACH DAY AS THE LARGE SCALE PATTERN IS SIMPLY
MORE FAVORABLE FOR WET/UNSETTLED CONDITIONS RATHER THAN HOT AND
DRY PATTERN.

CAVANAUGH

[NTXYankee]

Bam!

 

000

FXUS64 KFWD 092054

AFDFWDAREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE FORT WORTH TX

354 PM CDT THU APR 9 2015

.SHORT TERM...

THROUGH TONIGHT...THE PRIMARY FORECAST CONCERN IS THUNDERSTORM

CHANCES AND ASSOCIATED SEVERE WEATHER EXPECTATIONS FOR NORTH AND

CENTRAL TEXAS.

AT 3 PM CDT A COLD FRONT WAS LOCATED ALONG A LINE FROM GAINESVILLE

TO CISCO...MOVING SOUTHEAST TOWARDS THE DFW METROPLEX. FARTHER TO

THE SOUTHEAST...A PERSISTENT LOW-LEVEL WARM AIR ADVECTION REGIME

RESULTED IN THE INITIATION OF SCATTERED THUNDERSTORMS FROM WACO

NORTHEAST TO TERRELL AND EAST TOWARDS PALESTINE. LOCAL CONVECTIVE

PARAMETERS INDICATE THAT SURFACE BASED CONVECTION IS ONLY CAPPED

BY 50 J/KG OF INHIBITION OR LESS FOR MOST LOCATIONS SOUTHEAST OF

THE COLD FRONT. AS A RESULT...THERE IS A CHANCE THAT ANYTHUNDERSTORM ACTIVITY THAT DEVELOPS WILL BECOME SURFACE BASED

THROUGH SUNSET.

SURFACE BASED CONVECTION HAS ANYWHERE FROM 1500 TO 2500 J/KG OF

AVAILABLE ENERGY FOR UPDRAFT GROWTH (CAPE)...WHICH IS CERTAINLY

ENOUGH TO SUPPORT STORMS STRONG ENOUGH TO PRODUCE SEVERE WEATHER

IMPACTS. DEEP LAYER SHEAR OVER THE REGION WAS ON THE ORDER OF 30

TO 35 KTS IN THE 0-6 KM LAYER...WHICH IS ON THE LOW END OF WHAT IS

TYPICALLY CONSIDERED SUFFICIENT FOR SUPERCELLS/ROTATING UPDRAFTS.

LOW-LEVEL WIND PROFILES ARE CHARACTERIZED BY 0-1 KM HELICITY

VALUES OF LESS THAN 50 M2/S2 WHICH IS NOT VERY SUPPORTIVE OF LOW-

LEVEL UPDRAFT ROTATION. AS A RESULT...THE TORNADO POTENTIAL FOR

MOST OF THE CWA APPEARS TO BE LOW AT THIS TIME. THIS IS MAINLY DUE

TO VEERED LOW-LEVEL WINDS ASSOCIATED WITH A PREFRONTAL TROUGH OUT

AHEAD OF THE COLD FRONT. THESE VEERED WINDS EXTEND TO A LINE FROM

APPROXIMATELY ATHENS TO TEMPLE. ALONG AND SOUTHEAST OF AN ATHENS

TO TEMPLE LINE...SURFACE WINDS ARE BACKED...RESULTING IN A LOW-

LEVEL SHEAR PROFILE MORE SUPPORTIVE OF LOW-LEVEL ROTATING UPDRAFTS

AND A TORNADO POTENTIAL. WILL BE WATCHING THIS AREA CLOSELY FOR AN

ENHANCED SUPERCELL/TORNADO POTENTIAL THROUGH SUNSET AS A RESULT.

EXPECT THAT STORMS WILL DEVELOP ALONG THE COLD FRONT BEFORE

SUNSET...WHICH WOULD BE IN ADDITION TO THE STORMS THAT WERE

ALREADY DEVELOPING IN THE WARM AIR ADVECTION REGIME WELL SOUTHEAST

OF THE FRONT. INITIALLY ELEVATED THUNDERSTORMS WILL LIKELY BECOME

SURFACE BASED AS UPDRAFTS PERSIST AND EVENTUALLY INGEST THE FAIRLYUNSTABLE AIR LOCATED BELOW THE NOW WEAK CAPPING INVERSION ALOFT.

THE INITIAL STORM MODE MAY BE DISCRETE SUPERCELLS ONCE STORMS

TRANSITION TO SURFACE BASED...HOWEVER THIS STORM MODE IS NOT

EXPECTED TO LAST LONG. SOMEWHAT MARGINAL DEEP LAYER SHEAR WILLLIKELY NOT BE ENOUGH TO KEEP COLD POOLS SEPARATED...AND COOLOUTFLOW MERGERS AND UPSCALE GROWTH INTO MULTI-CELL CLUSTERS OR A

QLCS IS LIKELY. THE PRIMARY HAZARDS ASSOCIATED WITH ORGANIZED

STORMS THROUGH THIS EVENING ARE LARGE HAIL AND DAMAGING WINDS. THE

ONLY DIFFERENCE IN THREAT FOR SUPERCELLS COMPARED TO MULTI-CELLS

IS THAT THE HAIL WILL TEND TO BE LARGE IN SUPERCELL STORMS. THETORNADO THREAT FOR MOST LOCATIONS IS LOW...BUT WE WILL KEEP A

CLOSE EYE ON ANY SURFACE BASED STORMS NEAR THE SMALL PORTION OF

THE SOUTHEASTERN CWA WHERE LOW-LEVEL WINDS ARE BACKED AROUND TO

THE SSE.

THE COLD FRONT IS EXPECTED TO ADVANCE SOUTH ACROSS CENTRAL TEXAS

OVERNIGHT. THUNDERSTORMS SHOULD DIMINISH IN INTENSITY AND COVERAGE

AS THE FRONT CONTINUES SOUTH TONIGHT. COOLER AND DRIER AIR IS

EXPECTED TO BUILD ACROSS THE CWA BY FRIDAY MORNING BEHIND THE COLDFRONT.

&&

.LONG TERM...

FRIDAY THROUGH SUNDAY...THE COLD FRONT IS EXPECTED TO SINK SOUTH

TOWARDS THE TEXAS GULF COAST ON FRIDAY...LEAVING THE CWA IN A

RELATIVELY COOL AND DRIER AIRMASS FOR MUCH OF THE DAY ON FRIDAY.

ANOTHER UPPER LEVEL STORM SYSTEM...EMBEDDED WITHIN THE

SUBTROPICAL JET...WILL BE APPROACHING THE REGION THIS WEEKEND. THEFLOW ALOFT COMING OFF OF THE HIGH TERRAIN THE SOUTHERN CONUS AND

NORTHERN MEXICO WILL RESULT IN LEE SIDE TROUGHING OVER THE

SOUTHERN HIGH PLAINS BY FRIDAY AFTERNOON. THIS WILL INITIATE A

QUICK RESPONSE TO SOUTHERLY FLOW ALOFT OVER THE SHALLOW COLD

FRONTAL INVERSION BY FRIDAY AFTERNOON. DO NOT EXPECT MUCH IN THE

WAY OF PRECIPITATION/STORMS OVER NORTH OR CENTRAL TEXAS ON FRIDAY

AS IT WILL TAKE THIS SOUTHERLY FLOW ALOFT SOME TIME TO ADVECT RICH

GULF MOISTURE BACK OVER THE CWA. DID MAINTAIN SOME 20 POPS OVER

THE SOUTHERN CWA FRIDAY AFTERNOON HOWEVER TO ACCOUNT FOR THE

WARM/MOIST ASCENT OVER THE FRONTAL INVERSION.

SATURDAY AND SUNDAY...THE LEE SIDE TROUGH AND APPROACHING UPPER

LEVEL STORM SYSTEM WILL WORK IN TANDEM TO KEEP PERSISTENT MOIST

ASCENT OVER NORTH AND CENTRAL TEXAS THROUGH THE WEEKEND. FORECAST

SOUNDINGS INDICATE THAT THIS MAY RESULT IN SCATTERED ELEVATED

THUNDERSTORMS ACROSS THE CWA DURING THE DAY ON SATURDAY. THE AREAS

MOST LIKELY TO SEE THUNDERSTORMS ARE THOSE WEST OF INTERSTATE 35

AND SOUTH OF INTERSTATE 20 WHERE THE WARM/MOIST ADVECTION REGIME

IS FORECAST TO BE STRONGEST IN MODEL MASS FIELDS. THIS PERSISTENT

LIFT SPREADS NORTH AND EAST DURING THE DAY ON SUNDAY...MAKINGSCATTERED STORMS MORE LIKELY ACROSS THE ENTIRE CWA BY SUNDAY

AFTERNOON.

WITHOUT A WELL-DEFINED FRONT...EXPECT MOST THUNDERSTORM ACTIVITY

TO BE HIT AND MISS THIS WEEKEND...WITH THE GREATEST COVERAGE OF

STORMS STARTING OFF SOUTHWEST ON SATURDAY...AND EXPANDING NORTH

AND EAST ON SUNDAY. SEVERE WEATHER ON SATURDAY APPEARS TO BE

UNLIKELY BECAUSE STORMS ARE EXPECTED TO REMAIN ELEVATED IN NATURE.

SEVERE WEATHER CHANCES INCREASE ON SUNDAY AS PERSISTENT WARM/MOISTADVECTION MAY RESULT IN SOME NEAR SURFACE BASED STORMS. THINK THAT

WIDESPREAD CLOUD COVER WILL TEND TO LIMIT POTENTIAL INSTABILITY

THROUGH...SO THINK THAT MOST STORMS WILL REMAIN SUB-SEVERE ON

SUNDAY.

MONDAY...THE UPPER LEVEL STORM SYSTEM EMBEDDED IN THE SUB-TROPICALJET IS EXPECTED TO MOVE OVER THE SOUTHERN HIGH PLAINS ON MONDAY

WHILE BECOMING CUT OFF COMPLETELY FROM THE MUCH FASTER POLAR JET

STREAM TO THE NORTH. MOST MODEL GUIDANCE IS IN LINE WITH THIS

EVOLUTION FOR THIS UPPER LEVEL STORM SYSTEM...SO CONFIDENCE IS

FAIRLY HIGH IN THIS GENERAL PATTERN TAKING SHAPE. WITH A LARGE

UPPER TROUGH TO OUR WEST...AND A VERY WARM AND MOIST LOW-LEVEL AIR

MASS IN PLACE ACROSS THE REGION...THIS IS SYNOPTICALLY A VERY GOOD

SET UP FOR THUNDERSTORM CHANCES ACROSS THE CWA ON MONDAY.

THE CIPS ANALOG GUIDANCE PAGE HOSTED BY ST. LOUIS UNIVERSITY

INDICATES THAT THIS SYNOPTIC PATTERN IS SIMILAR IN PLACEMENT AND

DYNAMIC STRENGTH TO STORM SYSTEMS THAT HAVE HISTORICALLY RESULTED

IN HIGH IMPACT SEVERE WEATHER OUTBREAKS ACROSS NORTH OR CENTRAL

TEXAS. MODEL GUIDANCE INDICATES THAT A STATIONARY FRONT WILL LINE

UP JUST NORTH OF THE INTERSTATE 20 CORRIDOR ON MONDAY...WITH THE

SUBTROPICAL JET LOCATED OVER THE CWA WITHIN THE BASE OF THIS CUT-

OFF UPPER LOW TO OUR WEST. THIS WOULD SET UP A FAVORABLE

ENVIRONMENT FOR STRONG SHEAR OVER THE CWA WHICH COULD POTENTIALLY

BE SUPPORTIVE OF SUPERCELLS. THE PRIMARY LIMITING FACTOR FOR

SEVERE STORMS APPEARS TO BE THE EXTENT OF CLOUD COVER AND RAIN

SOUTH OF THE STATIONARY FRONT DURING THE DAY ON MONDAY. HERE ARE A

COUPLE OF SCENARIOS...ASSUMING THAT THE LARGE SCALE SYNOPTIC

PATTERN WILL HAPPEN AS ADVERTISED (WHICH IS NEVER 100 PERCENT

CERTAIN 4-5 DAYS OUT):

1. WIDESPREAD RAIN SHOWER AND THUNDERSTORM ACTIVITY OCCURS ALL

ALONG AND OUT AHEAD OF THE STATIONARY BOUNDARY. THIS APPEARS TO BE

THE MOST LIKELY SCENARIO TO PAN OUT AS ALL MODEL GUIDANCE FAVORS

THIS SOLUTION AT THIS TIME. THIS WOULD LIMIT HEATING WHICH WOULD

LIMIT POTENTIAL INSTABILITY FOR STRONG/SEVERE STORMS MONDAY

AFTERNOON. WHILE THIS LIMITS THE SEVERE WEATHER POTENTIAL BY

REDUCING LAPSE RATES FROM THE SURFACE TO THE TROPOPAUSE...THIS

ALSO RESULTS IN A DEEPER MOIST LAYER IN PLACE OVER THE CWA. THIS

SYNOPTIC SET UP SEEMS VERY FAVORABLE FOR HEAVY RAINFALL AND

POTENTIALLY FLOODING...ESPECIALLY NEAR THE STATIONARY BOUNDARY. IF

THE STATIONARY BOUNDARY DOES WIND UP OVER THE DFW METROPLEX...

THERE WOULD BE A PRETTY GOOD THREAT FOR FLASH FLOODING FROM MONDAY

MORNING THROUGH MONDAY NIGHT. THIS IS WHAT WE ARE GOING WITH IN

THE CURRENT FORECAST. NO FLOOD WATCHES WILL BE ISSUED AT THIS TIME

BECAUSE A LOT CAN CHANGE IN 4-5 DAYS...BUT THE POTENTIAL FOR

FLOODING WILL REMAIN A PRIMARY CONCERN AS WE HEAD THROUGH THE

WEEKEND INTO MONDAY.

2. IF CLOUDS ARE ABLE TO SCATTER OUT SOUTH OF THE FRONT...AND

THERE IS LITTLE TO NO RAINFALL SOUTH OF THE STATIONARY BOUNDARY ON

MONDAY...CONDITIONS WOULD SEEM TO BECOME MUCH MORE SUPPORTIVE FOR

A LOCAL SEVERE WEATHER EVENT. SOME OF THE ANALOGS THAT THE CIPSALGORITHM CAME UP WITH WERE THE PARIS AND LANCASTER TORNADO

EVENTS...SO THE LARGE SCALE ENVIRONMENT COULD CERTAINLY SUPPORT

SUPERCELLS THAT MAY PRODUCE TORNADOES. HOWEVER...THE ANALOG PAGE

IS JUST THAT...STATISTICALLY COMPARING LARGE SCALE PARAMETERS TO

WHAT MEDIUM RANGE GUIDANCE IS INDICATING FOR MONDAY. SINCE ALL

AVAILABLE GUIDANCE INDICATES THAT WE WILL REMAIN CLOUDY WITHSCATTERED SHOWERS AND THUNDERSTORMS SOUTH OF THE STATIONARYFRONT...THIS SCENARIO APPEARS UNLIKELY TO PAN OUT AT THIS TIME.

NEEDLESS TO SAY...IT LOOKS LIKE MONDAY IS A FAVORABLE DAY FOR HIGH

IMPACT WEATHER ACROSS PORTIONS OF NORTH AND CENTRAL TEXAS. IT

APPEARS THAT THE MOST LIKELY HAZARD WILL BE HEAVY RAINFALL AND

FLOODING...BUT WE WILL KEEP A VERY CLOSE EYE ON THE EVOLUTION OF

THIS SYSTEM JUST IN CASE SCENARIO 2 LOOKS MORE LIKELY IN THE

FUTURE.

REMAINDER OF THE WEEK...WE REMAIN IN A FAIRLY WET AND UNSETTLED

WEATHER PATTERN FOR THE WEEK AHEAD. MAINTAINED A LOW CHANCE OF

THUNDERSTORMS EACH DAY AS THE LARGE SCALE PATTERN IS SIMPLY

MORE FAVORABLE FOR WET/UNSETTLED CONDITIONS RATHER THAN HOT AND

DRY PATTERN.

CAVANAUGH

Bam for what?