Severe Weather Season 2012

[toxictwister00]

October off to a lion start, I'm under a Tornado Watch.

http://www.spc.noaa.gov/products/watch/ww0658.html

[Mr. Rainman]

It looks like Mother Nature is gearing up for another severe weather session on Saturday across the northern Mississippi Valley into Iowa and Missouri as a cut-off low swings northeastward into the Midwest. Looks like damaging winds and possibly a few tornadoes will be the main threats.

[toxictwister00]

Mesoscale Discussion

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MESOSCALE DISCUSSION 2139
   NWS STORM PREDICTION CENTER NORMAN OK
   1238 PM CST SUN DEC 09 2012
   
   AREAS AFFECTED...SWRN INTO NERN AR...SERN MO...FAR SRN IL...WRN
   KY/TN
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
   
   VALID 091838Z - 092045Z
   
   PROBABILITY OF WATCH ISSUANCE...40 PERCENT
   
   SUMMARY...PORTIONS OF SWRN INTO NERN AR...SERN MO...FAR SRN IL...AND
   WRN KY/TN ARE BEING MONITORED FOR A WW THIS AFTERNOON. PRIMARY SVR
   WEATHER THREAT WILL BE LARGE HAIL/DAMAGING WIND GUSTS...THOUGH A
   TORNADO OR TWO WILL ALSO BE POSSIBLE.
   
   DISCUSSION...EARLY AFTERNOON SURFACE ANALYSIS PLACES AN AREA OF LOW
   PRESSURE OVER CNTRL AR...WITH A COLD FRONT EXTENDING SWWD INTO CNTRL
   TX...AND A WARM FRONT SLOWLY RETREATING NWD OVER WRN/CNTRL KY. AS AN
   UPPER TROUGH CONSOLIDATES AND DEEPENS OVER THE CNTRL CONUS THIS
   AFTERNOON/EVENING...THE SURFACE LOW IS FORECAST TO EJECT NEWD INTO
   THE LOWER OH VALLEY...AND THE WARM FRONT WILL CONTINUE LIFTING NWD
   INTO SRN IND/OH.
   
   MEANWHILE...A 30-40 KT SWLY LLJ HAS AIDED IN TRANSPORTING LOW TO MID
   60F DEWPOINTS ALONG AN AXIS FROM SWRN AR INTO WRN KY/TN. IN
   ADDITION...POCKETS OF CLEARING OVER AR HAVE ALLOWED TEMPERATURES TO
   LOCALLY WARM TO AROUND 70F...WHICH HAS AIDED IN BOUNDARY LAYER
   DESTABILIZATION AND THE DEVELOPMENT OF AGITATED CUMULUS CLOUD
   STREETS. WV AND VIS SATELLITE IMAGERY SHOW A PLUME OF HIGH LEVEL
   CLOUDINESS OVERSPREADING THE REGION...WHICH MAY INFER THE APPROACH
   OF A SUBTLE UPPER-LEVEL DISTURBANCE. ASCENT ASSOCIATED WITH THAT
   FEATURE COMBINED WITH CONTINUED SURFACE HEATING...CONTRIBUTING
   TOWARD SBCAPE VALUES FROM 500-1500 J/KG...MAY AID IN GRADUAL
   DEEPENING OF THE CUMULUS FIELD OVER AR AND EVENTUAL SCATTERED
   THUNDERSTORM DEVELOPMENT BY MID AFTERNOON.
   
   OTHERWISE...ASCENT ALONG THE COLD FRONT WILL STRENGTHEN BY LATE
   AFTERNOON/EVENING...AND BE SUFFICIENT FOR THE DEVELOPMENT OF
   SCATTERED TO NUMEROUS STORMS FROM WRN KY INTO SRN AR. IF CELLULAR
   ACTIVITY CAN DEVELOP DURING THE AFTERNOON...THEN DEEP-LAYER SHEAR
   NEAR 50 KT WILL FAVOR SUPERCELLS. IF STORMS QUICKLY ORGANIZE INTO
   LINES ALONG THE FRONT LATE THIS AFTERNOON/EVENING...THEN BOWING/LEWP
   STRUCTURES WILL BE MORE LIKELY. LARGE HAIL AND DAMAGING WIND GUSTS
   WILL BE THE PRIMARY SVR WEATHER THREATS WITH EITHER MODE OF
   CONVECTION. HOWEVER...A TORNADO OR TWO WILL BE POSSIBLE AS THE 30-40
   KT SWLY LLJ AIDS IN EFFECTIVE SRH VALUES FROM 150-250 M2 S-2.
   
   ..GARNER/HART.. 12/09/2012
   
   
   ATTN...WFO...PAH...MEG...LZK...SGF...SHV...
   
   LAT...LON   34079436 35209349 36749090 37378894 37028801 35708856
               33819192 33339390 34079436    
Outlooks for today/tomorrow. SPC is playing up a possible tornado threat specifically around Birmingham, AL tomorrow. (Day Two Outlook)

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DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1010 AM CST SUN DEC 09 2012
   
   VALID 091630Z - 101200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING FROM
   CENTRAL TX INTO THE LOWER OH VALLEY...
   
   AN EXPANSIVE UPPER TROUGH LIES ACROSS THE ENTIRE CONUS TODAY...WITH
   A VIGOROUS SHORTWAVE TROUGH DIGGING SOUTHWARD ACROSS THE ROCKIES.
   AT THE SURFACE...THE MAIN BAROCLINIC ZONE EXTENDS FROM TX INTO THE
   OH VALLEY.  THIS ZONE WILL BE THE FOCUS FOR SCATTERED SHOWERS AND
   THUNDERSTORMS TODAY AND TONIGHT.
   
   A FEW THUNDERSTORMS HAVE BEEN ONGOING THIS MORNING OVER PARTS OF
   MO/AR INTO THE TN/OH VALLEYS.  THIS ACTIVITY IS ASSOCIATED WITH LOW
   LEVEL WARM ADVECTION IN VICINITY OF 30-40 KNOT SOUTHWESTERLY LOW
   LEVEL JET.  THESE WINDS ARE ALSO HELPING TO TRANSPORT GULF MOISTURE
   NORTHWARD WITH 60S SURFACE DEWPOINTS EXPECTED AS FAR NORTH AS
   WESTERN KY BY LATE AFTERNOON.  EXTENSIVE CLOUD COVER WILL LIKELY
   LIMIT HEATING OVER THIS CORRIDOR...BUT THE APPROACH OF A STRONG COLD
   FRONT SHOULD RESULT IN INCREASING COVERAGE OF THUNDERSTORMS BY LATE
   AFTERNOON AND EARLY EVENING.  FORECAST SOUNDINGS FROM NORTHEAST TX
   INTO WESTERN KY/TN SHOW MODERATELY STEEP MID LEVEL LAPSE RATES AND
   MLCAPE VALUES OF AROUND 1000 J/KG.  SUFFICIENT DEEP LAYER SHEAR WILL
   PROMOTE SUPERCELL AND BOW/LEWP STRUCTURES OVER THIS REGION CAPABLE
   OF LOCALLY DAMAGING WIND GUSTS.  A TORNADO OR TWO IS ALSO POSSIBLE
   THIS EVENING AS LOW LEVEL WINDS STRENGTHEN FURTHER.  THE MAIN
   TORNADO THREAT APPEARS TO BE FROM CENTRAL AR/SOUTHEAST MO INTO
   WESTERN KY/TN.  STORMS ARE EXPECTED TO ORGANIZE INTO A QLCS BY LATE
   EVENING AND PROGRESS EASTWARD INTO PARTS OF NORTHERN MS/WESTERN TN
   THROUGH THE NIGHT.
   
   DURING THE EVENING...STORMS MAY DEVELOP SOUTHWARD ALONG THE COLD
   FRONT INTO PORTIONS OF EASTERN/CENTRAL TX.  GREATER
   MOISTURE/INSTABILITY ARE FORECAST TO BE PRESENT IN THIS AREA...WHICH
   MAY AID IN THE RISK OF HAIL IN ADDITION TO GUSTY WINDS IN THE
   STRONGER STORMS.
   
   ..HART/DISPIGNA.. 12/09/2012

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DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1129 AM CST SUN DEC 09 2012
   
   VALID 101200Z - 111200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF MS...AL AND
   GA...
   
   ...GULF COAST STATES...
   AN UPPER-LEVEL TROUGH OVER THE CNTRL AND SRN PLAINS WILL DEAMPLIFY
   ON MONDAY AND MOVE QUICKLY NEWD INTO THE OH VALLEY. AT THE START OF
   THE PERIOD...THUNDERSTORMS WILL LIKELY BE ONGOING AHEAD OF THE
   TROUGH ALONG A COLD FRONT EXTENDING FROM KY SWWD ACROSS TN...MS AND
   LA. THIS ACTIVITY WILL BE LOCATED ON THE WRN EDGE OF A 40 TO 50 KT
   LOW-LEVEL JET WHICH IS FORECAST TO MOVE NEWD AWAY FROM THE GULF
   COAST STATES MONDAY AFTERNOON. THIS MAY RESULT IN A GRADUAL DECREASE
   IN CONVECTIVE COVERAGE ESPECIALLY IN THE LATE AFTERNOON AS THE
   UPPER-LEVEL TROUGH MOVES NEWD AWAY FROM THE REGION. THE POTENTIAL
   FOR ORGANIZED THUNDERSTORMS SHOULD BE GREATEST EARLY IN THE DAY WHEN
   LOW-LEVEL SHEAR IS FORECAST TO BE THE STRONGEST.
   
   FORECAST SOUNDINGS AT 18Z MONDAY IN CNTRL AL GENERALLY SHOW SBCAPE
   VALUES IN THE 500 TO 750 J/KG RANGE WITH STRONG DEEP LAYER SHEAR
   PROFILES. IN SPITE OF THE WEAK INSTABILITY...0-6 KM SHEAR OF 55 TO
   60 KT MAY BE ENOUGH FOR A SEVERE THREAT DURING THE LATE MORNING AND
   EARLY AFTERNOON AS SFC TEMPS WARM AHEAD OF THE FRONT. THE BEST
   COMBINATION OF SHEAR AND INSTABILITY IS FORECAST TO BE LOCATED IN
   THE VICINITY OF BIRMINGHAM WHERE AN ISOLATED TORNADO THREAT AND/OR
   WIND DAMAGE THREAT COULD DEVELOP. BECAUSE OF THE WEAK
   INSTABILITY...WILL MAKE THE SLIGHT RISK AREA SMALLER AND SHIFTED
   SWD. FURTHER TO THE NORTHEAST ACROSS THE SRN APPALACHIAN MTNS...ANY
   SEVERE THREAT SHOULD REMAIN MARGINAL AND SHORT-LIVED DUE TO VERY
   WEAK INSTABILITY.
   
   ..BROYLES.. 12/09/2012   

[Trevor]

I'm in that MD. Hopefully we'll get something...

[phw115wvwx]

A tornado watch is in effect for that area until 9 PM CST.

[Localonthe8s]

I'm too lazy to check but is it because of that storm front coming through? Today's high in Dallas hit 82, tomorrow - 46. OUCH!

[toxictwister00]

Severe Thunderstorm Watch 678

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SEL8
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 678
   NWS STORM PREDICTION CENTER NORMAN OK
   550 PM CST SUN DEC 9 2012
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
   
          SOUTHERN ARKANSAS
          WESTERN AND NORTHERN LOUISIANA
          EXTREME WESTERN MISSISSIPPI
          SOUTHEAST TEXAS
   
   EFFECTIVE THIS SUNDAY AFTERNOON FROM 550 PM UNTIL MIDNIGHT CST.
   
   HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
   MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
   
   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 90
   STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH
   NORTHWEST OF MONTICELLO ARKANSAS TO 45 MILES SOUTHEAST OF
   HUNTSVILLE TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
   ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).
   
   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
   DO PRODUCE TORNADOES.
   
   OTHER WATCH INFORMATION...CONTINUE...WW 677...
   
   DISCUSSION...SCATTERED TSTMS NEAR FRONT...AS WELL AS CLUSTERED
   CONVECTION TO ITS E...SHOULD POSE RISK FOR SVR HAIL AND DAMAGING
   GUSTS THROUGH EVENING.  MRGL SUPERCELL SCENARIO EXISTS FOR
   DISCRETE/PREFRONTAL CONVECTION...WITH 45-55 KT EFFECTIVE SHEAR
   MAGNITUDES BUT WEAK NEAR-SFC WINDS.  EFFECTIVELY SFC-BASED PARCELS
   SHOULD PERSIST THROUGH ABOUT 06Z OVER MUCH OF AREA AS LONG AS
   WARM/MOIST ADVECTION OFFSETS DIABATIC SFC COOLING.  TSTMS NEAR FRONT
   SHOULD BE UNDERCUT QUICKLY...PER SPC MESOSCALE DISCUSSION 2141.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
   MOTION VECTOR 23035.
   
   
   ...EDWARDS

[toxictwister00]

For Sunday, December 16, 2012

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SPC AC 151730
   
   DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1130 AM CST SAT DEC 15 2012
   
   VALID 161200Z - 171200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS SOUTHEAST TX/CENTRAL GULF COAST
   STATES...
   
   ...SOUTHEAST TX/CENTRAL GULF COAST REGION TO TN VALLEY...
   BROAD CYCLONIC UPPER FLOW WILL PREVAIL OVER THE MAJORITY OF THE
   CONUS ON SUNDAY. SEVERAL LOW AMPLITUDE DISTURBANCES ALOFT WILL CROSS
   THE REGION /AND ADJACENT MIDWEST/ DURING THE PERIOD...BUT MORE
   SUBSTANTIAL TROUGH AMPLIFICATION IS EXPECTED TO OCCUR OVER THE
   PLAINS/OZARKS SUNDAY NIGHT/EARLY MONDAY.
   
   ISOLATED TO SCATTERED SHOWERS/SOME TSTMS WILL LIKELY BE ONGOING
   ACROSS THE REGION EARLY SUNDAY IN ASSOCIATION WITH PERSISTENT WARM
   ADVECTION AND A STEADY MOISTURE INFLUX AHEAD OF A FRONT. RELATIVELY
   WEAK LAPSE RATES ALOFT AND A LIMITED NORTHWARD MOISTURE
   RETURN...ALONG WITH CLOUD COVER/POSSIBLE PRECIPITATION...SHOULD
   LIMIT THE DEGREE OF DESTABILIZATION ACROSS THE REGION. EVEN
   SO...SOME OF THESE STORMS COULD BECOME SURFACE BASED AS THE BOUNDARY
   LAYER WARMS...WITH AT LEAST SOME ISOLATED SEVERE WIND/PERHAPS
   TORNADO POTENTIAL.
   
   THE MOST PROBABLE SCENARIO FOR STORM INTENSIFICATION MAY OCCUR
   ACROSS PARTS OF SOUTHEAST TX INTO LA/PARTS OF MS SUNDAY AFTERNOON
   AND SUNDAY NIGHT/EARLY MONDAY NEAR AN ADVANCING/ACCELERATING COLD
   FRONT. SOMEWHAT STRONGER DESTABILIZATION IS LIKELY IN THESE AREAS IN
   THE PRESENCE OF A HIGHER THETA-E AIRMASS...WITH THE REGION
   INCREASINGLY COMING UNDER THE INFLUENCE OF THE AMPLIFYING UPPER
   TROUGH OVER THE PLAINS/OZARKS BY SUNDAY NIGHT. WHERE STORMS DO
   INCREASE/MATURE...VERY STRONG DEEP LAYER SOUTHWESTERLY FLOW AND
   ASSOCIATED VERTICAL SHEAR OF 50-80 KT /0-6 KM/ WILL SUPPORT
   FAST-MOVING LINE SEGMENTS/SOME SUPERCELLS WITH ASSOCIATED POTENTIAL
   FOR DAMAGING WIND/ISOLATED TORNADOES.
   
   ..GUYER.. 12/15/2012   

[toxictwister00]

For those keeping tabs on the severe wx today/tomorrow, here's the first watch of the day. It includes the areas of SE Texas and the northern half of Louisiana.

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SEL2
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 682
   NWS STORM PREDICTION CENTER NORMAN OK
   550 AM CST SUN DEC 16 2012
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
   
          WESTERN...CENTRAL AND NORTHERN LOUISIANA
          SOUTHEAST AND EAST TEXAS
          COASTAL WATERS
   
   EFFECTIVE THIS SUNDAY MORNING AND AFTERNOON FROM 550 AM UNTIL 100
   PM CST.
   
   HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75
   MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
   
   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75
   STATUTE MILES NORTH AND SOUTH OF A LINE FROM 80 MILES SOUTHWEST
   OF COLLEGE STATION TEXAS TO 40 MILES NORTH NORTHEAST OF NATCHEZ
   MISSISSIPPI.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
   ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).
   
   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
   AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
   THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
   AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
   DO PRODUCE TORNADOES.
   
   DISCUSSION...TSTMS FCST TO CONTINUE INCREASING IN COVERAGE AND
   SPREAD FROM W-E ACROSS WW AREA...WHILE STRENGTHENING TO SVR LEVELS.
   STG MID-UPPER WINDS -- E.G. 90 KT OBSERVED AROUND 6 KM AGL OVER LDB
   PROFILER SITE -- WILL CONTRIBUTE TO FAVORABLE DEEP-LAYER SHEAR.
   MEAN-WIND AND DEEP-SHEAR VECTORS WILL BE ALIGNED NEARLY PARALLEL TO
   LOW-LEVEL FRONTAL/CONVERGENCE ZONE...SUPPORTING PREDOMINANT
   QUASI-LINEAR AND CLUSTERED MODES...WITH LEWPS AND SMALL BOWS
   POSSIBLE.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
   MOTION VECTOR 24035.
   
   
   ...EDWARDS

[Donovan]

Given that it's December, I'm quite shocked to see SC featured in a day 4-8 outlook. Very rarely do you get these, even during peak thunderstorm seasons.  Arkansas, Mississippi, and Tennessee are in the other part of the outlook as well.

[Mr. Rainman]

Fairly significant severe weather episode expected on Christmas Day. Widespread damaging winds and/or tornadoes, a few long-tracked, are possible across mainly LA/MS/AL.  Looks like this year is going to go out with a true bang.

[toxictwister00]

Moderate risk initiated for Christmas Day via SPC.

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SPC AC 240653
   
   DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1253 AM CST MON DEC 24 2012
   
   VALID 251200Z - 261200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF LA...SCNTRL MS
   AND WCNTRL AL...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
   PLAINS...LOWER MS VALLEY...TN VALLEY...ERN GULF COAST STATES AND SRN
   APPALACHIAN MTNS...
   
   ...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   

[toxictwister00]

Slight and Moderate Risk areas have been expended for Christmas Day.




In addition, the tornado threat has been elevated for those in the moderate risk area where strong, long lived tornadoes are possible, not only during the day tomorrow, but overnight tomorrow night as well as advised by The Storm Prediction Center. Given tomorrow is Christmas and people will be out and about traveling to see family I hope the media does whatever is necessary to keep folks abreast of the situation.

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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
   


[toxictwister00]

Snippets of AFDs across the Southeast region concerning severe weather...

Atlanta, GA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
645 PM EST MON DEC 24 2012

.PREV DISCUSSION... /ISSUED 320 PM EST MON DEC 24 2012/

..SEVERE STORMS LIKELY TUES NIGHT/WED MORNING...

SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
SEVERAL FORECAST CONCERNS THIS PERIOD...NOT THE LEAST OF WHICH IS
CHC FOR SIGNIFICANT SEVERE QLCS EVENT TUES NIGHT/WED MORNING.

SVR WX PARAMETERS
CONTINUE TO INCREASE. SBCAPE NOW PROGGED AT 500-1000 J/KG AND 0-1KM
BULK SHEAR OF 40-50KT VALID 06Z WED. CAPE AND SHEAR DROPS SOME BY
12Z...BU BY THE TIME THE EVENT ENDS...
TOTAL RAINFALL SHOULD NOT EXCEED 2 OR 2.5 INCHES. DO NOT ANTICIPATE
ANY FLOODING ISSUES DUE TO LONG TERM DRY SOIL CONDITIONS AND STEADY
RAINFALL RATES AROUND 1 INCH PER 6 HOURS.

EVEN IF SLOWER NAM IS RIGHT...TSRA WILL MOVE OUT OF FAR SE COUNTIES
BY 18Z WED. STRONG WEST WINDS WITH GUSTS TO 35 MPH LIKELY BEHIND
FRONT BUT SHOULD SUBSIDE AFTER SUNSET.T SVR THREAT WILL CONTINUE.

Houston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
334 PM CST MON DEC 24 2012

...INCREASING POTENTIAL FOR SEVERE WEATHER CHRISTMAS DAY...

MODELS ALL BRING
A STRONG JET INTO TEXAS OVERNIGHT WITH ONE INITIAL JET STREAK
MOVING OVER THE AREA AT 06Z TUE AHEAD OF THE MAIN JET. LARGE SCALE
ASCENT WILL INCREASE MORE AS THE NOSE OF THE JET PUSHES INTO C TX
AND E TX FROM 12-18Z TUE. GIVEN FAVORABLE JET DYNAMICS AND
DIFFLUENT FLOW ALOFT...EXPECT SFC LOW TO FORM ALONG WARM FRONT AND
MOVE ALONG IT. DEEP MOISTURE WILL NOT BE MUCH OF A QUESTION WITH
SFC DEWPOINTS IN THE 60S SOUTH OF THE BOUNDARY WITH PRECIP WATER
VALUES AROUND 1.4 INCHES. INSTABILITY WILL BE AN ISSUE FOR SEVERE
WEATHER BUT MODELS STILL SHOW AT LEAST 1000-1500 J/KG OF CAPE IN
THE WARM SECTOR WITH POSSIBLY 2000 J/KG ALONG THE COAST. ONE OF
THE OTHER ISSUES WILL BE CAPPING FROM ELEVATED MIXED LAYER. BOTH
NAM/GFS BUFR SOUNDINGS SHOW CAPPING IN THE 800-700MB LAYER FOR
KIAH AND POINTS SOUTHWARD. MODEL SOUNDINGS FROM KCXO/KUTS/KCLL
SHOW MUCH WEAKER CAP. DEEP LAYER SHEAR OF 50-60KTS AND LOW LEVEL
SHEAR AROUND 20-30KTS ARE EXPECTED TO BE STRONG ENOUGH FOR STORM
ROTATION. THE QUESTION WILL BE HOW MUCH THE CAP HOLDS AND HOW MUCH
THE CAP INHIBITS SURFACE BASED STORMS IN THE WARM SECTOR. STILL
ANY STORMS THAT CAN BE ROOTED IN THE BOUNDARY LAYER SHOULD ROTATE
AND TORNADOES WILL BE THE MAIN THREAT. THINK SPC DAY 1 AND 2
OUTLOOKS REALLY HIGHLIGHT THE THREAT. GENERALLY THIS WILL BE NORTH
OF I-10 MAINLY ALONG THE WARM FRONT AND FROM 3-4AM THROUGH NOON ON
CHRISTMAS DAY. THINK THE MAIN UNCERTAINTY WILL BE WHERE THE WARM
FRONT MOVES AND HOW STRONG CAPPING BECOMES.

Alexandria, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
318 PM CST MON DEC 24 2012

...INDICATIONS FOR SEVERE WEATHER EVENT TONIGHT INTO CHRISTMAS DAY
STILL EXIST...

.SYNOPSIS...
A POTENT UPPER AIR DISTURBANCE MOVING OUT OF THE SOUTHWEST U.S. TODAY
WILL HELP ENERGIZE AN ACTIVE JET STREAM OVER THE REGION...WITH A
DEVELOPING AND DEEPENING LOW PRESSURE SYSTEM OVER SOUTH CENTRAL
TEXAS BY MORNING THE RESULT. THESE SYSTEMS WILL COMBINE WITH
INCREASING GULF MOISTURE TO PRODUCE THE POTENTIAL FOR EPISODES OF
SEVERE WEATHER STARTING TONIGHT AND CONTINUING INTO THE DAY ON
CHRISTMAS. ALL INTERESTS SHOULD BE AWARE OF THIS SITUATION AND
PLACE ANY WEATHER RADIOS THEY MAY HAVE ON THE ALERT MODE BEFORE
GOING TO BED TONIGHT. ALSO...ONE MAY WANT TO MAKE SURE ALL OUTSIDE
CHRISTMAS DECORATIONS OR INFLATABLE CHRISTMAS OBJECTS ARE SAFELY
SECURE FROM THE POSSIBILITY OF STRONG WINDS.

CHRISTMAS DAY...DEEPENING LOW PRESSURE SYSTEM THAT IS EXPECTED TO
FORM OVER SOUTH CENTRAL TEXAS BY MORNING...WILL MOVE NORTHEASTWARD
TO BETWEEN LUFKIN AND TOLEDO BEND BY NOON...THEN QUICKLY TO THE
NORTHEAST INTO THE LOWER MISSISSIPPI VALLEY BY THE EVENING HOURS.
AS THE LOW APPROACHES...LOW LEVEL JET IS PROGGED TO INCREASE TO
OVER 50 KNOTS. MEANWHILE...LEFT EXIT REGION OF STRONG MID LEVEL
JET WILL REACH THE AREA DURING THE MORNING HOURS. THE STRONG LOW
LEVEL SHEAR WILL CAUSE THE POTENTIAL FOR DISCRETE ROTATING CELLS
WITH ISOLATED TORNADOES...ESPECIALLY NEAR THE WARM FRONT WHERE
VEERING LOW LEVEL WINDS WILL BE AT ITS GREATEST. THEREFORE...THE
BEST POTENTIAL FOR THESE ROTATING CELLS WILL BE ALONG AND NORTH OF
THE HIGHWAY 190 CORRIDOR...AND ACCORDINGLY SPC HAS THAT AREA
OUTLINED IN A MODERATE RISK FOR TOMORROW.

MEANWHILE...A SQUALL LINE IS EXPECTED TO DEVELOP DURING THE
MORNING HOURS OVER EAST TEXAS AHEAD OF THE COLD FRONT. THIS
PROGRESSIVE MOVING SQUALL LINE WILL BE AIDED BY 60 PLUS KNOT MID
LEVEL WINDS...AND FAVORABLE MID LEVEL LAPSE RATES...THAT WILL CREATE
THE POTENTIAL FOR DAMAGING STRAIGHT LINE WIND GUSTS AS THE LOW
LEVEL WIND PROFILE BECOMES MORE UNI-DIRECTIONAL. THIS SQUALL LINE
SHOULD BE EAST OF THE SABINE RIVER BY NOON TIME...AND CONTINUE TO
EAST THROUGH THE FORECAST AREA BY 6 PM.

Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
403 PM CST MON DEC 24 2012

...SEVERE WEATHER TO IMPACT THE REGION ON CHRISTMAS DAY...

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)...

WARM FRONTAL RAINS (AND POSSIBLY ELEVATED CONVECTION ALONG/SOUTH OF
I-20) WILL BEGIN TO OVERSPREAD THE REGION LATE TONIGHT AS THE
SURFACE LOW DEEPENS OVER EASTERN TEXAS AND TRANSLATES
EAST-NORTHEAST. INSTABILITY ISN`T OVERLY HIGH WITH THIS INITIAL
ACTIVITY BUT MUCAPES CLIMBING ABOVE 200-300J/KG CO-LOCATED WITH
INCREASING DEEP LAYER SHEAR/COLD TEMPS ALOFT MAY BE JUST ENOUGH FOR
SOME NICKEL TO QUARTER SIZE HAIL. WILL MONITOR THIS CLOSELY.

AS FOR STORM MODE...MOST OF THE HIGH-RES MODELS SHOW STORMS
ORGANIZING INTO A LINE OFF TO OUR WEST/SOUTHWEST TOMORROW MORNING
SHIFTING EAST...WITH THE MOST ROBUST CONVECTIVE ACTIVITY CONFINED
ALONG/SOUTH OF I-20. AGAIN...THIS WILL BE DETERMINED BY THE EXTENT
OF THE WARM SECTOR AND HOW FAR NORTH THE MOISTURE CAN PUSH. THIS
LINE WILL CERTAINLY POSE A 70+ MPH DAMAGING WIND RISK IN VICINITY OF
BOWING LINE SEGMENTS...IN ADDITION TO A SIGNIFICANT TORNADO RISK
GIVEN THE STRENGTH OF LOW LEVEL SHEAR IN PLACE. QUARTER SIZE HAIL IS
NOT OUT OF THE QUESTION EITHER GIVEN COLD TEMPS ALOFT/GOOD MID LEVEL
LAPSE RATES. THE MODELS ALSO SHOW POTENTIAL FOR SUPERCELLS TO
DEVELOP OUT AHEAD OF THE MAIN LINE...AND THESE CELLS WILL DEFINITELY
HAVE TO BE WATCHED CLOSELY FOR ROTATION AND TORNADO POTENTIAL.

AS FOR TIMING...THERE IS SOME QUESTION HOW EARLY THE LINE WILL BEGIN
TO IMPACT OUR SOUTHWESTERN AREAS...WHICH COULD BE AS EARLY AS MID TO
LATE MORNING BUT THINKING RIGHT NOW IS EARLY TO MID AFTERNOON.
SUPERCELLS AHEAD OF THE LINE COULD BEGIN TO IMPACT THE NATCHEZ AREA
EARLY TOMORROW MORNING SO FOLKS ACROSS THIS AREA NEED TO BE AWARE
EARLY. THE FAST-MOVING LINE SHOULD FINALLY SHIFT EAST OF THE REGION
BY EARLY TO MID EVENING. PLEASE REFER TO A TIMING GRAPHIC ON OUR WEB
PAGE FOR SPECIFICS.

[toxictwister00]

Dec 25, 2012 0600 UTC Day 1 Convective Outlook

Code: [Select]

SPC AC 250600
   
   DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1200 AM CST TUE DEC 25 2012
   
   VALID 251200Z - 261200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS SOUTHEAST TX AND PORTIONS
   OF LA/MS/AL/FL PANHANDLE...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE GULF COAST/SOUTHEAST
   STATES...
   
   ...A DANGEROUS CHRISTMAS DAY/NIGHT SEVERE WEATHER EPISODE IS LIKELY
   TO UNFOLD...INCLUDING THE POTENTIAL FOR STRONG TORNADOES AND
   WIDESPREAD DAMAGING WINDS...ACROSS PORTIONS OF THE GULF COAST REGION
   AND LOWER MS RIVER VALLEY...
   
   ...SYNOPSIS...
   A PROGRESSIVE LARGE SCALE FLOW PATTERN WILL PREVAIL OVER THE CONUS
   DURING THE PERIOD. THE PRIMARY SYSTEM OF FOCUS WITH RESPECT TO DEEP
   CONVECTION WILL BE A VIGOROUS SHORTWAVE TROUGH /AND ASSOCIATED
   STRONG UPPER JET STREAK/ AS IT SPREADS EASTWARD...AMPLIFIES...AND
   THEN BECOMES INCREASINGLY CLOSED/NEGATIVELY TILTED TONIGHT AS IT
   ADVANCES FROM THE SOUTHERN PLAINS TO THE LOWER MS VALLEY/TN VALLEY.
   
   ...GULF COAST REGION/LOWER MS VALLEY TO SOUTHEAST STATES...
   GIVEN THE LARGE SCALE SCENARIO AS PREVIOUSLY DESCRIBED...A SURFACE
   LOW IS EXPECTED TO STEADILY DEEPEN AS IT SPREADS NORTHEASTWARD FROM
   SOUTHEAST TX THIS MORNING TO THE TN VALLEY TONIGHT. AS THIS
   OCCURS...AN INCREASINGLY MOIST LOW-LEVEL AIRMASS WILL DEVELOP
   NORTHWARD IN TANDEM WITH A WEST-EAST ORIENTED WARM FRONT...WITH
   LOWER 60S DEWPOINTS /AND SOME MIDDLE 60S F NEAR THE COAST/ BECOMING
   INCREASINGLY PREVALENT WITHIN THE WARM SECTOR.
   
   INITIALLY...STRONG/POTENTIALLY SEVERE TSTMS ARE EXPECTED TO BE
   ONGOING THIS MORNING...ESPECIALLY ACROSS SOUTHEAST TX INTO LA. THIS
   INCLUDES THE POSSIBILITY OF ELEVATED SUPERCELLS NORTH OF THE WARM
   FRONT /MAINLY CAPABLE OF HAIL/...ALONG WITH AN INCREASING SURFACE
   BASED SEVERE THREAT NEAR/SOUTH OF THE WARM FRONT THIS MORNING ACROSS
   THE UPPER TX COAST/SOUTHERN LA. WITHIN AN INCREASINGLY MOIST AND
   HIGHLY SHEARED ENVIRONMENT...THIS INCLUDES THE POSSIBILITY OF AN
   EARLY DAY TORNADO/WIND DAMAGE THREAT THIS MORNING/EARLY AFTERNOON
   ACROSS SOUTHEAST TX INTO SOUTHERN LA.
   
   WITH TIME...THE AIRMASS WILL FURTHER DESTABILIZE INTO THIS AFTERNOON
   ESPECIALLY ACROSS CENTRAL/SOUTHERN LA AND SOUTHERN PORTIONS OF
   MS/AL...WITH 1000+ J/KG MLCAPE FOR AREAS WITHIN 150-200 MILES OF THE
   GULF COAST. LESSER...AND A BIT MORE UNCERTAIN...DESTABILIZATION IS
   EXPECTED CLOSER TO THE EAST-NORTHEASTWARD SURFACE LOW LATER
   TODAY/TONIGHT...LARGELY OWING TO PERSISTENT PRECIPITATION NEAR/NORTH
   OF THE WARM FRONT AND A LESSER INFLUX OF LOW-LEVEL MOISTURE.
   
   REGARDLESS...THIS DESTABILIZATION COUPLED WITH AN INCREASINGLY
   STRONG DEEP LAYER WIND FIELD...WITH 70-100 KT AT 500 MB AND
   110+ KT AT 250 MB...WILL RESULT IN DEEP LAYER SHEAR SUPPORTIVE OF
   ROTATING UPDRAFTS/SUPERCELLS. ACCENTUATED BY THE DEEPENING PHASE OF
   THE CYCLONE...EVENTUAL QLCS DEVELOPMENT SEEMS LIKELY TO OCCUR THIS
   AFTERNOON INTO TONIGHT NEAR/AHEAD OF THE EASTWARD-ADVANCING COLD
   FRONT...ALTHOUGH DISCRETE SUPERCELLS WILL REMAIN POSSIBLE WITHIN THE
   WARM SECTOR AND NEAR/IMMEDIATELY AHEAD OF THE EVOLVING QLCS...WHICH
   SEEMS LIKELY TO CROSS LA AND THE SOUTHERN HALVES OF MS/AL THROUGH
   TONIGHT. POTENTIALLY WIDESPREAD DAMAGING WINDS WILL BE POSSIBLE WITH
   SUSTAINED BOWING SEGMENTS. FURTHERMORE...A FEW STRONG/POTENTIALLY
   LONG-LIVED TORNADOES WILL ALSO BE POSSIBLE WITH DISCRETE SUPERCELLS
   AND/OR EVENTUAL EMBEDDED MESO-VORTICES LATER THIS
   AFTERNOON/TONIGHT...ESPECIALLY GIVEN 200-500 M2/S2 0-1 KM SRH
   COINCIDENT WITH A 50-70 KT LOW LEVEL JET LATE THIS
   AFTERNOON/TONIGHT.
   
   WHILE THE OVERALL SYSTEM STRENGTHENS...INSTABILITY WILL WANE LATE IN
   THE PERIOD. EVEN SO...A SEVERE THREAT MAY REACH AS FAR EAST AS PARTS
   OF AL...SOUTHEAST TN...AND WESTERN GA LATER TONIGHT...WITH SOME
   POTENTIAL FOR AREAS INCLUDING COASTAL SC BY THE EARLY MORNING HOURS
   OF WEDNESDAY.
   
   ..GUYER/SMITH.. 12/25/2012