Severe weather outbreak? December 25-26

[CrazyC83]

It could be a very rough Christmas for some in the lower Mississippi Valley...possible tornado outbreak or intense squall line.

SPC AC 230829

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0229 AM CST SUN DEC 23 2012

VALID 251200Z - 261200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
PLAINS...LOWER MS VALLEY AND CNTRL GULF COAST STATES...

...GULF COAST STATES...
AN IMPRESSIVE UPPER-LEVEL SYSTEM IS FORECAST TO MOVE EWD INTO THE
SRN PLAINS EARLY TUESDAY MORNING AS THE EXIT REGION OF A POWERFUL
MID-LEVEL JET MOVES INTO THE GULF COAST STATES. AHEAD OF THE
SYSTEM...MOISTURE IS FORECAST TO RETURN NWD INTO THE LOWER MS VALLEY
AND CNTRL GULF COAST STATES WITH MODERATE INSTABILITY DEVELOPING
ACROSS THE SRN AND WRN PART OF THE SLIGHT RISK AREA EARLY IN THE DAY
ON TUESDAY. A CLUSTER OF THUNDERSTORMS OR SQUALL-LINE MAY BE ALREADY
DEVELOPED BY DAYBREAK ON TUESDAY ACROSS EAST TX WITH ADDITIONAL
STORMS POSSIBLY ONGOING ACROSS THE LOWER MS VALLEY. MODEL FORECASTS
INCREASE CONVECTIVE COVERAGE ACROSS THE LOWER MS VALLEY AND APPEAR
TO MOVE A WELL-DEVELOPED MCS EWD ACROSS THE REGION DURING THE DAY.

FORECAST SOUNDINGS AT MIDDAY TUESDAY IN THE LOWER MS VALLEY DEVELOP
AN IMPRESSIVE SHEAR ENVIRONMENT AS THE MID-LEVEL JET APPROACHES THE
REGION FROM THE WEST. NAM FORECAST SOUNDINGS VALID TUESDAY AT 21Z
JUST SOUTHWEST OF JACKSON MS SHOW MLCAPE VALUES AROUND 1500 J/KG
WITH ABOUT 60 KT OF DEEP LAYER SHEAR. THIS COMBINED WITH 0-3 KM
STORM RELATIVE HELICITIES AROUND 400 M2/S2 COULD BE FAVORABLE FOR
SUPERCELLS AND TORNADOES. IF MANY CELLS CAN REMAIN DISCRETE...THEN
CONDITIONS COULD ALSO BE FAVORABLE FOR STRONG TORNADOES AS THE
LOW-LEVEL JET MOVES EWD ACROSS THE CNTRL GULF COAST STATES FROM
TUESDAY MORNING INTO THE AFTERNOON. AT THIS POINT...THE POTENTIAL
FOR WIDESPREAD WIND DAMAGE APPEARS JUST AS VIABLE. THE MAGNITUDE OF
THESE THREATS MAY DEPEND UPON THE DOMINANT STORM MODE. IF THE
FAVORED MODE ENDS UP BEING LINEAR...THEN WIND DAMAGE COULD BE THE
GREATER THREAT.

FORECAST SOUNDINGS ACROSS THE LOWER MS VALLEY AND CNTRL GULF COAST
STATES TUESDAY INTO TUESDAY NIGHT SHOW POTENTIAL FOR A SUBSTANTIAL
SEVERE WEATHER EVENT. THE COMBINATION OF SHEAR AND INSTABILITY
COMBINED WITH A POTENT WEATHER SYSTEM SUGGESTS A 30 PERCENT
PROBABILITY AND SIGNIFICANT SEVERE HATCHED AREA ARE WARRANTED. THE
SEVERE THREAT SHOULD CONTINUE INTO TUESDAY EVENING AND POSSIBLY INTO
THE OVERNIGHT PERIOD AS THE UPPER-LEVEL TROUGH MOVES QUICKLY EWD
ACROSS THE GULF COAST STATES.

..BROYLES.. 12/23/2012

CLICK TO GET WUUS03 PTSDY3 PRODUCT

NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z
CURRENT UTC TIME: 1526Z (10:26AM), RELOAD THIS PAGE TO UPDATE THE TIME

[Ntxw]

Dynamics of this system is extensive. People in Dixie should follow closely, hope no one sees tornadoes on Christmas but the possibility is growing.

[CrazyC83]

Dynamics of this system is extensive. People in Dixie should follow closely, hope no one sees tornadoes on Christmas but the possibility is growing.

I'd be worried about low awareness. Many radio and TV stations, especially in smaller markets, are understaffed at best on Christmas and many people would likely not pay as much attention about the weather as well. It could also put a strain on NWS offices if there is low staffing.

[cycloneye]

Here is a message from Dr Greg Forbes of TWC:

Dr. Greg Forbes

TUESDAY

Severe thunderstorm and tornado outbreak likely with hail, damaging gusts, and isolated tornadoes in east TX, LA, MS, AL, west and central FL panhandle.

TORCON - 5 central and south MS, 5 northeast LA, 5 central and southwest AL.

[psyclone]

this has significant potential. really this is a 3 day event starting Christmas eve in Texas and hitting the carolinas and georgia on the 26th with the core of the event Christmas day over southern LA,MS,AL the FL panhandle and perhaps working into GA late.

[TropicalAnalystwx13]

The potential is there for a few strong tornadoes, meaning tornadoes of EF2 intensity or greater. Large hail greater than 2" in diameter and damaging wind gusts over 70 mph will also be possible in a region stretching from eastern Texas to western Georgia and the Florida Panhandle on Christmas Day.

[CYCLONE MIKE]

Our local NWS office has been discussing this for a couple of days. Had a caution headline up this morning for possible severe weather outbreak christmas eve through christams day. With the low looking like it will be moving a little more off the the NE means we will get a greater influx of unstable gulf moisture to work with as far as storm development goes before main squall line gets here.

[yzerfan]

SPECIAL WEATHER STATEMENT...UPDATED
NATIONAL WEATHER SERVICE MOBILE AL
507 PM CST SUN DEC 23 2012

ALZ051>064-FLZ001>006-MSZ067-075-076-078-079-241600-
CHOCTAW-WASHINGTON-CLARKE-WILCOX-MONROE-CONECUH-BUTLER-CRENSHAW-
ESCAMBIA-COVINGTON-UPPER MOBILE-UPPER BALDWIN-LOWER MOBILE-
LOWER BALDWIN-INLAND ESCAMBIA-COASTAL ESCAMBIA-INLAND SANTA ROSA-
COASTAL SANTA ROSA-INLAND OKALOOSA-COASTAL OKALOOSA-WAYNE-PERRY-
GREENE-STONE-GEORGE-
INCLUDING THE CITIES OF...BUTLER...LISMAN...SILAS...CHATOM...
MILLRY...JACKSON...THOMASVILLE...GROVE HILL...CAMDEN...
PINE HILL...HOMEWOOD...MONROEVILLE...EVERGREEN...GREENVILLE...
LUVERNE...BRANTLEY...ATMORE...BREWTON...EAST BREWTON...
ANDALUSIA...OPP...MOBILE...PRICHARD...SARALAND...BAY MINETTE...
TILLMANS CORNER...THEODORE...DAPHNE...FAIRHOPE...FOLEY...
SPANISH FORT...CENTURY...FLOMATON...MOLINO...PENSACOLA...
FERRY PASS...BRENT...WEST PENSACOLA...BELLVIEW...ENSLEY...
MYRTLE GROVE...JAY...PACE...MILTON...GULF BREEZE...CRESTVIEW...
WRIGHT...FORT WALTON BEACH...NICEVILLE...DESTIN...SEMINOLE...
EGLIN AFB...VALPARAISO...WAYNESBORO...RICHTON...BEAUMONT...
NEW AUGUSTA...LEAKESVILLE...MCLAIN...WIGGINS...LUCEDALE
507 PM CST SUN DEC 23 2012

...SEVERE STORMS POSSIBLE ON CHRISTMAS DAY...

A POWERFUL LOW PRESSURE SYSTEM WILL MOVE ACROSS NORTHERN MISSISSIPPI
AND ALABAMA ON CHRISTMAS DAY...BRINGING A STRONG COLD FRONT ACROSS THE
AREA. UNSEASONABLY WARM...MOIST AND UNSTABLE AIR WILL BE INJECTED FROM
THE GULF OF MEXICO INTO THE SOUTHEAST STATES AHEAD OF THE FRONT. YOUR
NATIONAL WEATHER SERVICE OFFICE IN MOBILE HAS FOUND THAT THERE IS A
SUBSTANTIAL RISK OF SEVERE WEATHER IN SOUTHEAST MISSISSIPPI...SOUTHWEST
ALABAMA...AND THE WESTERN FLORIDA PANHANDLE ON CHRISTMAS DAY.

LATEST COMPUTER MODEL GUIDANCE CONTINUES TO INDICATE SCATTERED
STRONG TO SEVERE THUNDERSTORMS DEVELOPING THROUGH CHRISTMAS MORNING
AND AFTERNOON. THERE IS A RISK OF THESE STORMS PRODUCING TORNADOES
DURING THE DAY WITH SOME TORNADOES POSSIBLY STRONG. IN ADDITION...LARGE
HAIL WITH THESE STORMS IS LIKELY.

BY LATE AFTERNOON...A LINE OF THUNDERSTORMS WILL FORM OUT WEST ALONG
THE INTERSTATE 59 CORRIDOR IN MISSISSIPPI. THE LINE OF THUNDERSTORMS
WILL QUICKLY MOVE EAST...REACHING THE INTERSTATE 65 CORRIDOR BY EARLY
CHRISTMAS EVENING AND EAST OF A BRANTLEY/LUVERNE TO DESTIN LINE BY
MIDNIGHT. THE PRIMARY SEVERE WEATHER CONCERN ALONG THE SQUALL LINE
WILL BE DAMAGING STRAIGHT LINE WINDS...LARGE HAIL...AND ISOLATED
TORNADOES. THE THREAT OF SEVERE WEATHER IS EXPECTED TO END CHRISTMAS
NIGHT AS THE STRONG COLD FRONT EXITS THE AREA.

STAY TUNED FOR FURTHER UPDATES ON THIS POTENTIALLY DANGEROUS WEATHER
SITUATION.

$$

[Ntxw]

Not your typical December discussion...



***
...SIGNIFICANT SEVERE WEATHER EVENT SETTING UP FOR CHRISTMAS DAY FOR
PARTS OF THE GULF COAST STATES...

...LOWER MS VALLEY/GULF COAST STATES...
AN IMPRESSIVE UPPER-LEVEL SYSTEM IS FORECAST TO MOVE ACROSS THE SRN
PLAINS INTO THE LOWER MS VALLEY ON TUESDAY. A POWERFUL MID-LEVEL JET
IN THE BASE OF THE UPPER-LEVEL SYSTEM WILL TRANSLATE QUICKLY EWD
OVER A MOISTENING WARM SECTOR RESULTING IN THE POTENTIAL FOR A
SIGNIFICANT SEVERE WEATHER EVENT ACROSS PARTS OF THE LOWER MS VALLEY
AND CNTRL GULF COAST STATES. AS THE UPPER-LEVEL TROUGH APPROACHES
THE REGION...MODEL FORECASTS MOVE A BAND OF STRONG LARGE-SCALE
ASCENT QUICKLY EWD ACROSS CNTRL TX EARLY TUESDAY MORNING WHICH
COINCIDES WITH A MOISTENING BOUNDARY LAYER ACROSS MUCH OF THE TX
COASTAL PLAINS. IN RESPONSE...THUNDERSTORM DEVELOPMENT SHOULD BE
UNDERWAY AT DAYBREAK ON TUESDAY WITH A CLUSTER OF STRONG TO
POTENTIALLY SEVERE STORMS MOVING ENEWD FROM SE TX INTO THE LOWER MS
VALLEY AROUND MIDDAY.

FORECAST SOUNDINGS AT VICKSBURG AND JACKSON MS ON TUESDAY GRADUALLY
DEVELOP MODERATE INSTABILITY WITH SFC DEWPOINTS REACHING THE LOWER
TO MID 60S F. THIS COMBINED WITH STRENGTHENING DEEP LAYER SHEAR AS
0-6 KM SHEAR APPROACHES 60 KT BY EARLY AFTERNOON SHOULD BE FAVORABLE
FOR SUPERCELLS AND TORNADOES.0-3 KM STORM RELATIVE HELICITIES OF
350 TO 400 M2/S2 SHOULD BE SUPPORTIVE OF STRONG TORNADOES WITH THE
GREATEST THREAT ALONG A CORRIDOR FROM NEAR LAKE CHARLES LA TUESDAY
MORNING ACROSS SCNTRL MS INTO WCNTRL AL BY TUESDAY EVENING.
INSTABILITY...MOISTURE AND SHEAR PROFILES SUGGEST THAT ANY MCS THAT
BECOMES WELL-ORGANIZED COULD CONTAIN A TORNADO THREAT FOR AN
EXTENDED PERIOD. FOR THIS REASON...LONG TRACK TORNADOES COULD OCCUR
WITH SUPERCELLS THAT REMAIN DISCRETE AND MOVE ALONG THE NRN EDGE OF
MODERATE INSTABILITY. IN ADDITION...WIND DAMAGE WILL BE LIKELY WITH
LINE-SEGMENTS THAT ORGANIZE ON THE LEADING EDGE OF THE MCS. A THREAT
FOR WIDESPREAD WIND DAMAGE MAY DEVELOP ACROSS THE REGION TUESDAY
WITH WIND GUSTS OVER 70 KT POSSIBLE WITH BOWING SEGMENTS EMBEDDED IN
THE LINE. IF A WELL-DEVELOPED AND FAST MOVING SQUALL-LINE
ORGANIZES...THEN THE WIND DAMAGE THREAT COULD BECOME SUBSTANTIAL.
THE THREAT FOR SEVERE STORMS SHOULD CONTINUE THROUGH MUCH OF THE
OVERNIGHT PERIOD REACHING THE SRN APPALACHIAN MTNS AND ERN GULF
COAST STATES LATE TUESDAY NIGHT.

..BROYLES.. 12/24/2012

[CrazyC83]

Could this be a High Risk in the end? Honestly, being Christmas with low awareness, I would through every weapon out of the arsenal to get the message, even if it runs a bust risk.

[CrazyC83]

Wednesday (Boxing Day) looks active as well:

SPC AC 240831

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0231 AM CST MON DEC 24 2012

VALID 261200Z - 271200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE ERN GULF
COAST STATES...FL PENINSULA...CAROLINAS AND MID-ATLANTIC...

...CAROLINAS/ERN GULF COAST STATES/MID-ATLANTIC...
AN IMPRESSIVE NEGATIVELY-TILTED UPPER-LEVEL SYSTEM IS FORECAST TO
MOVE QUICKLY NEWD ACROSS THE ATLANTIC COASTAL REGION ON WEDNESDAY.
AN UPPER-LEVEL LOW OVER THE MID MS VALLEY AT DAYBREAK ON WEDNESDAY
SHOULD MOVE NEWD ACROSS THE OH VALLEY AS A SLAB OF VERY STRONG
LARGE-SCALE ASCENT MOVES FROM THE ERN GULF COAST STATES EWD ACROSS
THE CAROLINAS WEDNESDAY AFTERNOON. DUE TO THE STRONG FORCING...A
WELL-DEVELOPED SQUALL-LINE SHOULD BE ONGOING AT 12Z ON WEDNESDAY
WITH THIS LINEAR CONVECTIVE SYSTEM REMAINING INTACT ALL THE WAY TO
THE COAST.

FORECAST SOUNDINGS AT 21Z/WED AHEAD OF THE SQUALL-LINE IN ERN NC AND
NCNTRL SC SHOW INCREASING INSTABILITY DURING THE LATE MORNING AND
EARLY AFTERNOON WITH SFC DEWPOINTS REACHING THE LOWER 60S F. THIS
MAY ALLOW MODERATE INSTABILITY TO DEVELOP ACROSS PARTS OF THE ERN
CAROLINAS WEDNESDAY AFTERNOON. IN ADDITION...A WELL-DEVELOPED
LOW-LEVEL JET COMBINED WITH A POWERFUL MID-LEVEL JET WRAPPING AROUND
THE UPPER-LEVEL LOW WILL CREATE STRONG DEEP LAYER SHEAR PROFILES
FAVORABLE FOR SEVERE STORMS. ACROSS MUCH OF THE REGION...WINDS IN
THE BOUNDARY LAYER ARE FORECAST TO EXCEED 50 KT JUST ABOVE THE SFC
WHICH SHOULD ENABLE ANY LINE OF STORMS TO BE EFFICIENT AT PRODUCING
WIND DAMAGE. IF DISCRETE CELLS CAN INITIATE AHEAD OF THE APPROACHING
SQUALL-LINE...THEN A SUBSTANTIAL TORNADO THREAT COULD ALSO DEVELOP
WEDNESDAY AFTERNOON WITH THE POTENTIAL FOR A STRONG TORNADO.
CONSIDERING THE STRENGTH OF THE UPPER-LEVEL SYSTEM WHICH COMBINED
WITH MODERATE INSTABILITY AND STRONG DEEP LAYER SHEAR...ANY SEVERE
THREAT THAT DEVELOPS ACROSS THE CAROLINAS COULD BECOME ENHANCED. FOR
THIS REASON...A 30 PERCENT SEVERE PROBABILITY WITH A SIGNIFICANT
HATCHED AREA APPEARS WARRANTED.

FURTHER TO THE NORTH ACROSS THE MID-ATLANTIC...ANY SEVERE THREAT
WITH THE LINE OF STORMS SHOULD BE MORE ISOLATED DUE TO WEAKENING
INSTABILITY WITH NWD EXTENT. TO THE SOUTH ACROSS ERN GA AND NRN
FL...A SUBSTANTIAL WIND DAMAGE THREAT COULD EXIST BUT THE THREAT
SHOULD DECREASE WITH SWD EXTENT DUE TO WEAKER LARGE-SCALE ASCENT AND
DEEP LAYER SHEAR.

..BROYLES.. 12/24/2012

CLICK TO GET WUUS03 PTSDY3 PRODUCT

NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0830Z
CURRENT UTC TIME: 1502Z (10:02AM), RELOAD THIS PAGE TO UPDATE THE TIME

[CrazyC83]

http://www.srh.noaa.gov/bmx/?n=mmbrief

NWS Birmingham briefing.

[CrazyC83]

SPC AC 241722

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1122 AM CST MON DEC 24 2012

VALID 251200Z - 261200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF LA...CENTRAL/SRN
MS...AND WRN AL...

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN TX ACROSS THE GULF
COAST/LOWER MS VALLEY AND SRN APPALACHIANS...

...SIGNIFICANT SEVERE WEATHER EVENT EXPECTED FOR CHRISTMAS DAY OVER
PARTS OF THE GULF COAST STATES...

...SYNOPSIS...
AN ENERGETIC FLOW PATTERN IS EVIDENT IN SATELLITE IMAGERY FROM THE
EASTERN PACIFIC ACROSS THE CONUS AS A SERIES OF VIGOROUS UPPER
TROUGHS PROGRESS EWD. THE PRIMARY SYSTEM ASSOCIATED WITH A MAJOR
SEVERE WEATHER THREAT TOMORROW IS CURRENTLY OVER THE GREAT BASIN.
WITH LATEST UPPER AIR DATA INDICATING THE STRONGEST MID/UPPER LEVEL
WINDS DIGGING INTO THE SWRN PORTION OF THE TROUGH...MODEL CONSENSUS
INDICATES THE SYSTEM WILL AMPLIFY/DEVELOP INTO A PROGRESSIVE CLOSED
LOW MOVING ACROSS THE SRN PLAINS DURING THE DAY REACHING THE MIDDLE
MS VALLEY BY 26/12Z. AT THE SURFACE...A BROAD LOW PRESSURE REGION
OVER CENTRAL/ERN TX EARLY IN THE PERIOD IS FORECAST TO CONSOLIDATE
INTO A DEEPENING LOW MOVING ACROSS NRN LA DURING THE AFTERNOON AND
CONTINUING INTO MIDDLE TN BY THE END OF THE PERIOD. AN EAST-WEST
ORIENTED WARM FRONT FROM SERN TX ACROSS THE SRN PARTS OF MS/AL AND
GA WILL SLOWLY LIFT NWD AS THE LOW MOVES NEWD...WHILE A COLD FRONT
EXTENDING SWWD FROM THE LOW IS EXPECTED TO ACCELERATE EWD
/ESPECIALLY DURING THE NIGHT/ ACROSS THE LOWER MS VALLEY REACHING AL
BY 26/12Z.

...GULF COAST REGION/LOWER MS VALLEY...
AREAS OF STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO BE ONGOING FROM
ERN TX INTO THE LOWER MS VALLEY AT THE START OF THE PERIOD AS
INTENSE LARGE SCALE ASCENT IN THE LEFT EXIT REGION OF THE UPPER
LEVEL JET COINCIDES WITH FOCUSED LOW LEVEL CONVERGENCE/WARM
ADVECTION ALONG/NORTH OF THE WARM FRONT. SOUTH OF THE WARM
FRONT...SURFACE DEW POINTS IN THE LOW/MID 60S F WILL BE RETURNING
NWD ACROSS A BROAD WARM SECTOR EXTENDING ACROSS MUCH OF THE GULF
COAST REGION. THIS WILL CONTRIBUTE TO AN UNSTABLE ENVIRONMENT WITH
MLCAPE RANGING FROM 1000-1250 J/KG NEAR THE COAST TO AOB 500 J/KG
NORTH OF THE WARM FRONT.

STRONG WINDS IN THE MID AND UPPER LEVELS /70-90 KT AT 500 MB AND
110+ KT AT 250 MB/ WILL RESULT IN DEEP LAYER SHEAR SUPPORTIVE OF
ROTATING UPDRAFTS...INCLUDING ELEVATED SUPERCELLS NORTH OF THE WARM
FRONT. AS THE DAY PROGRESSES...FORCED ASCENT ALONG THE ADVANCING
COLD FRONT IS EXPECTED TO RESULT IN QLCS DEVELOPMENT CONTAINING
EMBEDDED FAST-MOVING BOW ECHOES AND POSSIBLE
SUPERCELLS/MESO-VORTICES AS IT MOVES EWD ACROSS LA AND THE SRN HALF
OF SRN MS. THERE WILL ALSO BE CONTINUED POTENTIAL FOR A FEW
DISCRETE SUPERCELLS IN THE WARM SECTOR AND ALONG THE WARM FRONT
AHEAD OF THE QLCS. LOW LCL HEIGHTS AND CLOCKWISE TURNING LOW LEVEL
HODOGRAPHS /SRH VALUES OF 200-400 M2 PER S2/ INDICATE POTENTIAL FOR
TORNADIC SUPERCELLS. THE POSSIBILITY EXISTS FOR SEVERAL LONG-TRACK
STRONG TORNADOES ASSOCIATED WITH ANY LONG-LIVED FAST-MOVING
SUPERCELLS...ALONG WITH MORE WIDESPREAD DAMAGING WINDS ALONG THE
MOST INTENSE PARTS OF THE BOWING QLCS. DESPITE GRADUALLY DECREASING
INSTABILITY AS BOUNDARY LAYER COOLING OCCURS AFTER DARK...A SEVERE
THREAT IS EXPECTED TO SPREAD EWD/NEWD ACROSS PARTS OF AL...SRN TN
AND WRN GA DURING THE NIGHT AS THE SYSTEM CONTINUES TO STRENGTHEN.

..WEISS.. 12/24/2012

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NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0700Z
CURRENT UTC TIME: 1751Z (12:51PM), RELOAD THIS PAGE TO UPDATE THE TIME

[cycloneye]

[Portastorm]

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DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1029 AM CST MON DEC 24 2012

VALID 241630Z - 251200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVERNIGHT FOR PORTIONS
CENTRAL-E TX AND WRN LA...

...SYNOPSIS...
PROGRESSIVE UPPER-AIR PATTERN WAS ANALYZED THIS MORNING OVER
CONUS...FEATURING TWO SHORTWAVE TROUGHS OF PRIMARY PERTINENCE TO
THIS FCST INITIALLY OVER...
1. MID-SOUTH REGION TO MS/AL COAST. THIS FEATURE WILL MOVE EWD AND
DEAMPLIFY SLIGHTLY BEFORE MOVING OFFSHORE SC AROUND 03Z.
2. INLAND PAC NW SSEWD ACROSS NV. PERTURBATION IS FCST TO
STRENGTHEN THROUGH PERIOD AND MOVE SEWD ACROSS CENTRAL/SRN
ROCKIES...REACHING CENTRAL/SRN HIGH PLAINS BY 12Z. EMBEDDED/500-MB
CLOSED LOW SHOULD FORM BY 12Z OVER TX PANHANDLE/SOUTH-PLAINS
REGION...WHILE MID-UPPER HEIGHT GRADIENT INTENSIFIES MARKEDLY TO ITS
SW-SE. BY 12Z...EXPECT 500-MB JET MAX 90-100 KT OVER SERN NM/TX
PERMIAN BASIN REGION...WITH FLOW STRENGTHENING TO 60-70 KT RANGE
OVER SFC WARM SECTOR IN SE TX.

AT SFC...WEAK LOW NOW OVER NRN KY IS FCST TO PROCEED NEWD UP OH
VALLEY THROUGH REMAINDER DAYLIGHT HOURS AND WEAKEN...WITH OCCLUSION
TRIPLE-POINT LOW POSSIBLY FORMING INVOF SERN NY COASTAL WATERS
AROUND 06Z. ACCOMPANYING SFC COLD FRONT WAS ANALYZED AT 15Z FROM
LOW SSWWD ACROSS NRN AL...SWRN MS...SWRN LA...AND S-CENTRAL TX. TX
PORTION OF BOUNDARY IS DECELERATING...AND IS FCST TO MOVE NWD ACROSS
PORTIONS CENTRAL/SE TX OVERNIGHT AS WARM FRONT. MEANWHILE...LEE
CYCLONE IS FCST TO DEEPEN CONSIDERABLY TODAY ACROSS NERN NM AND SERN
CO REGION...WITH APCH OF AMPLIFYING TROUGH ALOFT. DURING LAST 6
HOURS OF PERIOD...SFC CYCLONE WILL TRANSITION TO FRONTAL-WAVE
FEATURE AND MOVE/REPOSITION SEWD ALONG ZONE OF
FRONTOGENESIS...REACHING POSITION OVER CENTRAL TX BY 12Z.

...TX/LA AREA OVERNIGHT...
CONVECTIVE POTENTIAL WILL INCREASE OVERNIGHT...FIRST N OF SFC FRONT
LATE EVENING THROUGH PRE-DAWN HOURS WITH MOST INTENSE CELLS POSING
HAIL THREAT. ACTIVITY MAY DEVELOP PROGRESSIVELY CLOSER TO FRONT
THROUGH END OF PERIOD...EVENTUALLY BECOMING SFC-BASED WITH
SUPERCELLS AND BOW/LEWP FEATURES POSSIBLE. AS SUCH...THREAT EXISTS
DURING LAST FEW HOURS OF PERIOD FOR SVR HAIL/GUSTS. TORNADO RISK
EXISTS FROM ANY SFC-BASED AND RELATIVELY DISCRETE CELLS IN WHAT
SHOULD BE VERY FAVORABLE SHEAR ENVIRONMENT...BUT COVERAGE OF
SFC-BASED TSTMS IS TOO UNCERTAIN ATTM FOR MORE THAN 5% UNCONDITIONAL
TORNADO RISK.

DEEP SHEAR AND LOW-LEVEL HODOGRAPHS EACH ARE EXPECTED TO STRENGTHEN
OVER RETURNING WARM SECTOR TONIGHT...AS 60S F SFC DEW POINTS
CONTRIBUTE TO 1000-1500 J/KG MLCAPE BY 12Z ALONG AND S OF FRONT OVER
SE TX. LARGEST LOW-LEVEL HODOGRAPHS WILL BE ALONG FRONT...WHERE
BACKED SFC WINDS WILL CONTRIBUTE TO EFFECTIVE SRH 300-500 J/KG. SRH
ALSO WILL BE FAVORABLE FARTHER S OVER COASTAL AREAS IN WARM
SECTOR...HOWEVER FCST SOUNDINGS SUGGEST PRONOUNCED EML-BASE
INVERSION BETWEEN 850-700 MB THAT MAY RESTRICT TSTM COVERAGE AWAY
FROM BOUNDARIES.

...CENTRAL-ERN GULF COASTAL PLAIN...NEXT 4-6 HOURS...
BULK OF CONVECTION IS EXPECTED TO OUTRUN LOW-LEVEL DESTABILIZATION
OVER THIS REGION THROUGH REMAINDER DAYLIGHT HOURS. HOWEVER...AT
LEAST ISOLATED TSTMS STILL MAY DEVELOP OVER THIS AREA THROUGH AROUND
21Z...SOME OF WHICH MAY BECOME SFC-BASED. DAMAGING WIND AND TORNADO
RISKS ARE NONZERO BUT VERY CONDITIONAL. DESTABILIZATION WILL BE
SLOWED BY ONGOING CLOUDS/PRECIP...WHICH WILL RESTRICT PACE OF
DIURNAL WARMING. LOW-LEVEL THETAE ADVECTION SHOULD RESULT IN
POTENTIAL INFLOW PARCELS EFFECTIVELY BECOMING SFC-BASED ACROSS THIS
REGION THROUGH MID-AFTN...WHILE DEEP-LAYER ASCENT WEAKENS. THESE
OFFSETTING INFLUENCES WILL AFFECT TSTM COVERAGE...BUT ANY
SUSTAINED/SFC-BASED CONVECTION HAS POTENTIAL TO BECOME
SUPERCELLULAR. AS SUCH...WILL MAINTAIN MRGL UNCONDITIONAL SVR
PROBABILITIES FOR THIS OUTLOOK.

[PTrackerLA]

It sure it warm and humid out there. Currently 74 degrees feeling more like April than December 24th! Concerned about this severe weather event tomorrow especially the thought of tornadoes in the area while everyone is trying to enjoy Christmas day .

[WeatherGuesser]

Twisters to the south, Blizzard to the north.

Could be interesting.

[CrazyC83]

If the SPC goes all-in with a High Risk tomorrow, it would be the first in December in 10 years.

It should seriously be considered, to boost awareness given the large number of distractions for Christmas. The message needs to get out...

[WeatherGuesser]

^ Most people are so entrenched in family mode, they're not even watching TV or anything else. Web traffic is even down on most of the boards I frequent.

[CrazyC83]

^ Most people are so entrenched in family mode, they're not even watching TV or anything else. Web traffic is even down on most of the boards I frequent.

That is a great concern I have, there may not be a lot of people paying attention on TV or anything. In addition, it is certainly possible some media outlets (especially in smaller markets) will be on autopilot or closed, and NWS offices may have a hard time getting the staff necessary.