2013 U.S Severe Weather: Videos / Photos / Stats / Forecasts

[cycloneye]

There will be a possible outbreak for the 29-30 of January timeframe.

CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0342 AM CST THU JAN 24 2013

VALID 271200Z - 011200Z

...DISCUSSION...
MODEL TRENDS CONTINUE TO BE CLOSELY MONITORED FOR THE POSSIBILITY OF
SIGNIFICANT SEVERE WEATHER AROUND TUE/D6 AND POSSIBLY INTO WED/D7.

INSPECTION OF THE ECMWF...GFS...CMC...UKMET AND VARIOUS MREF MEMBERS
REVEALS VERY GOOD AGREEMENT WITH THE PATTERN EVOLUTION THROUGH ABOUT
108 HOURS OR VALID MON/D5 AT 12Z. ALTHOUGH DIFFERENCES EXIST FURTHER
OUT...THEY ARE MOSTLY IN RELATION TO TIMING AND LOCATION OF THE
LIKELY SEVERE THREAT.

A WEAK LEAD SHORTWAVE TROUGH IS EXPECTED TO DE-AMPLIFY ACROSS THE
MID MS VALLEY ON SUN/D4...WITH A SUBTLE UPPER RIDGE ACROSS THE OH/TN
VALLEYS. THIS PATTERN WILL MAINTAIN SELY FLOW ACROSS THE GULF OF
MEXICO AROUND THE SURFACE HIGH WHICH SHOULD BE CENTERED JUST OFF THE
MID ATLANTIC COAST ON MON/D5. AS SUCH...LOW LEVEL MOISTURE WILL
CONTINUE TO INCREASE WITH MID 60S F BOUNDARY LAYER DEWPOINTS AS FAR
N AS DALLAS.

SINCE THE QUALITY OF THE LOW LEVEL MOISTURE RETURN DOES NOT APPEAR
TO BE IN QUESTION...ATTENTION TURNS TO THE TIMING OF THE WRN TROUGH.
VIRTUALLY ALL MODELS SHOW A LARGE TROUGH THAT WILL MOVE EWD INTO THE
PLAINS AROUND TUE/D6 AND WILL CONTINUE EWD THROUGH D8.

MODELS ARE IN GOOD AGREEMENT WITH DEPICTING A LEADING SHORTWAVE
MOVING ACROSS THE CNTRL AND SRN PLAINS AND INTO THE MS VALLEY BY TUE
AFTERNOON. THE ECMWF AMPLIFIES THIS FEATURE MORE THAN THE
OPERATIONAL GFS...BUT IS IN AGREEMENT WITH THE CMC AND A FEW MREF
MEMBERS. IN THIS SCENARIO...A STRONGER SURFACE LOW FORMS FROM IA
INTO WI...WHICH WOULD EXPAND THE SEVERE THREAT FARTHER NWD ACROSS
IL. EVEN IF THE LESS AMPLIFIED GFS SITUATION DEVELOPS...SEVERE WOULD
STILL BE LIKELY ACROSS MUCH OF AR AND NERN TX WHERE LARGER MOISTURE
AND INSTABILITY WOULD BE PRESENT ALONG WITH STRONG SHEAR. HAVE
MAINTAINED PREVIOUS AREA AND EXPANDED NWD AND EWD SLIGHTLY FOR
TUE/D6.

FOR WED/D7...WHILE THE GFS APPEARS TO BE AN OUTLIER LAGGING THE MAIN
TROUGH OVER THE FOUR CORNERS...IT DOES INDICATE THE POTENTIAL FOR A
SECONDARY SHORTWAVE TO EJECT EWD ACROSS THE SRN PLAINS AND LOW MS
VALLEY ON WED/D7...THEN CONTINUING TOWARD THE E COAST ON D8. THE
MOST LIKELY SOLUTION AT THIS TIME LOOKS TO BE FOR A MORE MARGINAL
SEVERE THREAT PERSISTING INTO WED/D7 WITH THUNDERSTORMS ALONG A COLD
FRONT ACROSS MUCH OF THE ERN STATES. HOWEVER...PREDICTABILITY FOR D7
AND D8 IS QUITE LOW AT THIS TIME.

..JEWELL.. 01/24/2013

[cycloneye]

Latest outlook for next week's possible outbreak.


DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0325 AM CST SAT JAN 26 2013

VALID 291200Z - 031200Z

...DISCUSSION...
LATEST SUITE OF MODEL GUIDANCE PRESENTS A BETTER GENERAL CONSENSUS
IN THE FORECAST EVOLUTION OF THE LARGE SCALE PATTERN ACROSS THE
CONUS INTO THE MIDDLE OF NEXT WEEK...ESPECIALLY WHEN COMPARED TO
THIS TIME YESTERDAY. WHILE THERE REMAIN DIFFERENCES IN THE
CONFIGURATIONS AND MAGNITUDES OF THE VARIOUS FLOW FIELDS AND
PARAMETERS...ANALYSIS OF THE GFS/ECMWF/UKMET/CMC/GFS ENSEMBLE AND
DPROG/DT LOOPS LEND SUFFICIENT SUPPORT FOR THE REINTRODUCTION OF A
SEVERE WEATHER FORECAST...NOW VALID FOR D4/TUESDAY...WITH A
CONTINUING THREAT INTO AT LEAST PART OF D5/WEDNESDAY.

AS INDICATED IN THE D3 OTLK...A WARM MOIST BOUNDARY LAYER IS
EXPECTED TO RESIDE ACROSS THE SCNTRL U.S. AHEAD OF A STRENGTHENING
LARGE SCALE TROUGH AND ASSOCIATED DEVELOPING COLD FRONT. WHILE ECMWF
CONTINUES TO FORECAST A SLIGHTLY SLOWER AND LESS FULLY-PHASED UPPER
TROUGH WHEN COMPARED WITH GFS/UKMET MODELS...EVEN IT COMES AROUND TO
FORECASTING AN AMPLIFIED AND SUBSTANTIALLY PHASED LARGE SCALE UPPER
TROUGH ACROSS THE SCNTRL AND ERN U.S. BEGINNING D4/TUESDAY AND
CONTINUING THROUGH D5/WEDNESDAY. THIS PROCESS WILL CONTRIBUTE TO A
RAPID ONSET OF DEEP-LAYER ASCENT AND SUBSEQUENT TSTM DEVELOPMENT
ALONG AND AHEAD OF A SHARPENING COLD FRONT THAT WILL SWEEP EWD/SEWD
ACROSS THE CNTRL/SRN PLAINS DURING THE DAY TUESDAY...AND THEN TO THE
TN VALLEY/NRN GULF COAST AND SOUTHEAST THROUGH WEDNESDAY. SHEAR AND
INSTABILITY AS CURRENTLY FORECAST WILL PROMOTE ORGANIZED STORMS IN
EITHER SUPERCELL OR LINEAR FORMS FROM NORTHEAST TX ACROSS THE
ARKLATEX TO SERN MO/WRN TN. SQUALL LINE OR LINE SEGMENT EVOLUTION
SHOULD BECOME MORE LIKELY WITH TIME AS COLD FRONT/CONVECTIVE COLD
POOLS FURTHER INTENSIFY AMIDST MODEST INSTABILITY. DAMAGING
WINDS...POSSIBLY WIDESPREAD...WILL BE THE GREATEST HAZARD WITH THIS
CONVECTION. HOWEVER...LOW LEVEL SHEAR WILL BE STRONG ENOUGH FOR
TORNADOES AS WELL.

EXPECT THE STRONG FORCING AND SHEAR TO MAINTAIN A QLSC WITH DAMAGING
WIND POTENTIAL AT LEAST INTO THE TN VALLEY THROUGH EARLY
WEDNESDAY/D5. BEYOND THIS TIME...GREATER MODEL SPREAD AND RESULTING
UNCERTAINTY BEGIN TO IMPACT FORECAST CONFIDENCE IN SEVERE WEATHER.
HAVE OPTED TO RELY ON GFS ENSEMBLE JOINT PROBABILITY FORECASTS FOR
INSTABILITY AND SHEAR THROUGH LATE WEDNESDAY. THESE PRODUCTS SUGGEST
THAT SEVERE WEATHER POTENTIAL WILL BE MUCH MORE UNCERTAIN WITH EWD
EXTENT DESPITE STRONG QPF AND UVV SIGNALS ALONG THE ADVANCING FRONT
TO THE EAST COAST. PORTIONS OF THE SOUTHEAST MAY BE ADDED IN LATER
OUTLOOKS IF MODEL CONSENSUS IMPROVES.

..CARBIN.. 01/26/2013

[Cyclenall]

I'll be following this as it went to a very rare D7 outlook this week.

There is a new page launched by the SPC that is called the Tornado Environment Browser: http://www.spc.noaa.gov/exper/envbrowser/

Something new there.

[cycloneye]

Slight Risk for day 3

They add at the end of the discussion that it may go up to Moderate Risk status.

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0224 AM CST SUN JAN 27 2013

VALID 291200Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM TX NORTHEAST TO IL AND
EAST ACROSS THE LOWER MS VALLEY...

...SYNOPSIS...
A POTENT HIGH AMPLITUDE UPPER TROUGH AND ASSOCIATED COLD FRONT WILL
SWEEP EAST AND SOUTH ACROSS THE PLAINS/MIDWEST AND LOWER MS VALLEY
FROM TUESDAY INTO EARLY WEDNESDAY. THIS SYSTEM COULD PRODUCE A
FAIRLY WIDESPREAD SWATH OF SEVERE WEATHER FROM CNTRL AND NERN
TX...NRN LA...ACROSS MUCH OF AR AND SERN MO...AND EAST AND SOUTH
ACROSS THE MS RIVER FROM IL TO MS. WHILE IT IS TOO EARLY TO BE
OVERLY DETAILED REGARDING THE CHARACTER OF THIS EVENT...THE
SIZE...STRENGTH...AND RAPID EVOLUTION OF THE LARGE SCALE TROUGH
SYSTEM...AS CURRENTLY FORECAST...SUGGESTS THE DEVELOPMENT OF AN
EXTENSIVE AND FAST-MOVING SQUALL LINE CAPABLE OF PRODUCING DAMAGING
WINDS ACROSS SOME OR ALL OF THE ABOVE MENTIONED AREAS FROM AROUND
MID-DAY TUESDAY INTO EARLY WEDNESDAY.

...TX TO IL SOUTHEAST ACROSS THE LOWER MS VALLEY...
PREFER THE SOMEWHAT SLOWER AND NOT SO PHASED DEPICTION OF THE UPPER
TROUGH AS SHOWN BY LATEST ECMWF AND NAM THROUGH EARLY TUESDAY. THESE
SCENARIOS INDICATE A MOIST BUT GENERALLY WEAK TO MODERATELY UNSTABLE
AIRMASS WILL BE SITUATED FROM TX NEWD ACROSS MO AND INTO IL BY
TUESDAY AFTERNOON. LACK OF STRONGER INSTABILITY WILL LIKELY BE
COMPENSATED FOR BY RELATIVELY RAPID ONSET OF INTENSE ASCENT
ASSOCIATED WITH THE APPROACH OF MID/UPPER TROUGH AND 100KT MID LEVEL
SPEED MAX SPREADING OUT ACROSS THE WARM SECTOR TO NEAR ARLATEX BY
AROUND 00Z. DEEP CONVECTION WILL ERUPT ALONG THE ENTIRE LENGTH OF
THE SHARPENING COLD FRONT THROUGH THE LATE AFTERNOON WITH STORMS
COMING UNDER THE INFLUENCE OF EVER INCREASING DEEP-LAYER SHEAR/FLOW.
EXTENSIVE QLCS APPEARS LIKELY TO SPREAD EAST ACROSS THE MID/LOWER MS
VALLEY INTO TUESDAY NIGHT WITH CELL MOTIONS FORECAST IN EXCESS OF
50KT LEADING DAMAGING WINDS. LACK OF STRONGER CYCLONIC DEVELOPMENT
ALONG THE COLD FRONT SUGGESTS LINEAR MODE SHOULD DOMINATE BUT
SUPERCELLS AND LEWPS EMBEDDED IN THE LINE AND NEAR TRANSIENT FRONTAL
WAVE STRUCTURES WOULD POSE SOME TORNADO THREAT WITH TIME.
[b]UNCERTAINTIES REGARDING OVERALL TIMING AND DEGREE OF SURFACE-BASED
DESTABILIZATION PRECLUDE HIGHER OR SIGNIFICANT PROBABILITIES AT THIS
FORECAST RANGE. HOWEVER...FUTURE UPGRADE TO MDT RISK SEEMS POSSIBLE
IF THESE DETAILS BECOME CLEARER.

..CARBIN.. 01/27/2013
[/b]

[cycloneye]

Day 2 Outlook

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1242 AM CST MON JAN 28 2013

VALID 291200Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER OH/MID MS VALLEY
REGION SWWD INTO NERN TX...

...SYNOPSIS...
A HIGHLY AMPLIFIED/PROGRESSIVE UPPER PATTERN WILL AFFECT THE U.S.
THIS PERIOD...WITH A STRONG TROUGH FORECAST TO EXIT THE ROCKIES AND
SHIFT INTO THE CENTRAL PORTION OF THE COUNTRY WITH TIME.

AS THE STRONG/SHARP TROUGH ADVANCES...A SHARPENING COLD FRONT IS
FORECAST TO SHIFT ACROSS THE PLAINS DURING THE FIRST HALF OF THE
PERIOD...AND THEN CONTINUE EWD OVERNIGHT. BY THE END OF THE
PERIOD...THIS BOUNDARY SHOULD STRETCH FROM LOWER MI SWD TO THE
CENTRAL GULF COAST AND ON INTO THE GULF OF MEXICO. IT IS THIS FRONT
WHICH WILL FOCUS A ZONE OF STRONG/LOCALLY SEVERE CONVECTION ACROSS
PARTS OF THE CENTRAL U.S. -- PARTICULARLY DURING THE LATE AFTERNOON
AND EVENING HOURS.

...LOWER OH/MID MS VALLEYS SWWD INTO NERN TX...
SHOWERS AND PERHAPS A THUNDERSTORM OR TWO SHOULD BE ONGOING AT THE
START OF THE PERIOD ACROSS PARTS OF OK AND ADJACENT N TX/SRN
KS...AHEAD OF THE SHARPENING SURFACE FRONT. CONVECTION SHOULD
REMAIN GENERALLY SUB-SEVERE HOWEVER INTO THE AFTERNOON...AS
MOISTENING/WEAK DESTABILIZATION OF THE PRE-FRONTAL AIRMASS OCCURS.

BY MID TO LATE AFTERNOON...500 J/KG MIXED-LAYER CAPE SHOULD COMBINE
WITH INCREASING ASCENT WITH THE APPROACH OF THE UPPER SYSTEM TO
RESULT IN AN INCREASE IN CONVECTIVE COVERAGE/INTENSITY ALONG/AHEAD
OF THE COLD FRONT. WHILE STORMS FROM ROUGHLY THE MS VALLEY NEWD
INTO IL SHOULD STRUGGLE TO BECOME TRULY SURFACE-BASED THUS LIMITING
SEVERE POTENTIAL...STORMS FROM MO SWD WILL BE OCCURRING IN A
SUFFICIENTLY MOIST BOUNDARY LAYER TO PERMIT DAMAGING WIND/TORNADO
POTENTIAL. WITH THE MAIN SURFACE LOW TO REMAIN WELL TO THE
N...MINIMAL LOW-LEVEL VEERING MAY LIMIT OVERALL TORNADO POTENTIAL.
HOWEVER...STRONG SPEED SHEAR GIVEN A RAPIDLY STRENGTHENING FLOW
FIELD WITH HEIGHT WILL SUPPORT ORGANIZED STORMS CAPABLE OF PRODUCING
DAMAGING GUSTS AND LIKELY A FEW ISOLATED TORNADOES.

THREAT SHOULD CONTINUE THROUGH THE EVENING AND INTO THE OVERNIGHT
HOURS...WITH LINEAR EVOLUTION OF THE CONVECTION EXPECTED WITH TIME.
DAMAGING WIND POTENTIAL MAY EVENTUALLY SPREAD E OF THE MS RIVER
VALLEY...THOUGH THE GREATEST THREAT SHOULD OCCUR DURING THE EVENING
WITHIN A REGION EXTENDING FROM THE ARKLATEX REGION NEWD ACROSS THE
OZARKS.

..GOSS.. 01/28/2013



Day 3 Outlook

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0151 AM CST MON JAN 28 2013

VALID 301200Z - 311200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE GULF COAST
STATES...MID SOUTH REGION...AND MID/SRN ATLANTIC COAST STATES...

...SYNOPSIS...
CONTINUED EWD PROGRESSION OF A LARGE CENTRAL/ERN NOAM TROUGH IS
FORECAST THIS PERIOD...THOUGH REINFORCEMENT OF THE TROUGH ON ITS WRN
FRINGE SUGGESTS A BROAD AREA OF CYCLONIC FLOW SHOULD COVER MOST OF
THE U.S. BY THE END OF THE PERIOD.

AT THE SURFACE...A COLD FRONT INITIALLY EXTENDING FROM ROUGHLY LOWER
MI SWD TO THE CENTRAL GULF COAST REGION IS FORECAST TO MAKE STEADY
EWD PROGRESS...MOVING OFF THE MIDDLE ATLANTIC COAST DURING THE
EVENING AND THEN VACATING THE ENTIRE ERN SEABOARD OVERNIGHT. PRIOR
TO MOVING OFFSHORE...THIS FRONT WILL CONTINUE TO FOCUS
CONVECTION...AND POTENTIAL FOR DAMAGING WINDS ACROSS PORTIONS OF THE
CENTRAL AND ERN CONUS.

...CENTRAL GULF COAST/MID SOUTH REGION EWD TO THE ATLANTIC COAST...
SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING TO START THE PERIOD
NEAR/AHEAD OF THE ADVANCING COLD FRONT...FROM THE MIDWEST SWD TO THE
MOUTH OF THE MS RIVER. THIS BAND OF CONVECTION WILL MARCH STEADILY
EWD ALONG WITH THE CORRESPONDING COLD FRONT...BUT VERY MODEST
INSTABILITY -- PARTICULARLY FROM THE MID SOUTH/CAROLINAS NWD --
SHOULD ACT TO HINDER OVERALL SEVERE POTENTIAL.

HAVING SAID THAT...VERY STRONG FLOW ALOFT WILL EXIST...WHICH WILL
FAVOR LOCALLY GUSTY/DAMAGING WINDS EVEN IN AREAS WITH LITTLE CAPE --
AND PERHAPS NO LIGHTNING.

ATTM...GREATEST POTENTIAL FOR DAMAGING WINDS APPEARS TO EXIST FROM
ERN KY/ERN TN SWD INTO MS/ERN LA/AL/THE FL PANHANDLE AND INTO GA AND
THE CAROLINAS...WHERE AN ISOLATED TORNADO OR TWO COULD ALSO OCCUR.
THE THREAT SHOULD REMAIN GENERALLY W OF THE APPALACHIANS THROUGH
EARLY AFTERNOON...SPREADING EWD ACROSS THE ATLANTIC COAST STATES
THROUGH THE AFTERNOON AND INTO THE EVENING BEFORE STORMS MOVE
OFFSHORE.

..GOSS.. 01/28/2013

[cycloneye]

...THERE IS A MDT RISK OF SVR TSTMS FROM NRN LA...CNTRL AND ERN
AR...EXTREME SWRN TN AND NWRN TO WCNTRL MS...

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE SRN
PLAINS...LOWER THROUGH MID MS VALLEY INTO WRN PARTS OF THE TN AND OH
VALLEYS...


DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1130 AM CST MON JAN 28 2013

VALID 291200Z - 301200Z

...THERE IS A MDT RISK OF SVR TSTMS FROM NRN LA...CNTRL AND ERN
AR...EXTREME SWRN TN AND NWRN TO WCNTRL MS...

...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE SRN
PLAINS...LOWER THROUGH MID MS VALLEY INTO WRN PARTS OF THE TN AND OH
VALLEYS...

...SYNOPSIS...

THE HIGH AMPLITUDE UPPER TROUGH NOW OVER THE WRN U.S. WILL ADVANCE
EWD...WITH MODEL CONSENSUS INDICATING THAT THE TROUGH AXIS WILL BE
LOCATED FROM MN THROUGH CNTRL/ERN TX BY THE END OF THIS PERIOD. MID
LEVEL JET AND ATTENDANT VORT MAX LOCATED WITHIN BASE OF THE TROUGH
SHOULD EJECT FROM THE SRN PLAINS THROUGH THE LOWER-MID MS VALLEY
TUESDAY NIGHT. AS THIS OCCURS A CYCLONE WILL DEEPEN AND LIFT NEWD
THROUGH THE MID MS VALLEY REGION. A POLAR FRONT WILL EXTEND FROM THE
SFC LOW OVER IA SWWD INTO CNTRL/SRN HIGH PLAINS EARLY TUESDAY...WITH
A PACIFIC FRONT/DRYLINE EXTENDING SWD THROUGH WRN TX. POLAR FRONT
WILL ADVANCE SEWD DURING THE DAY...WHILE THE PACIFIC FRONT SURGES
EWD AND MERGES WITH DRYLINE...CONTINUING THROUGH THE LOWER MS VALLEY
OVERNIGHT.

...SRN PLAINS THROUGH LOWER MS VALLEY REGION...

POTENTIAL EXISTS FOR A SIGNIFICANT SEVERE WEATHER EVENT TUESDAY WITH
DAMAGING WIND AND TORNADOES THE PRIMARY THREATS...ESPECIALLY DURING
THE EVENING AND OVERNIGHT IN MODERATE RISK AREA. OBSERVATIONS SHOW A
RESERVOIR OF MIDDLE TO UPPER 60S DEWPOINTS FROM CNTRL INTO SRN TX.
SLY BOUNDARY LAYER FLOW ALREADY EXISTS FROM THE SRN PLAINS INTO THE
LOWER MS VALLEY AND WILL STRENGTHEN TUESDAY IN ASSOCIATION WITH AN
INTENSIFYING LLJ. WIDESPREAD MULTI-LAYER CLOUDS WILL LIMIT BOUNDARY
LAYER WARMING DURING THE DAY. HOWEVER...MID 60S DEWPOINTS SHOULD
ADVECT AS FAR NORTH AS SERN OK INTO CNTRL AR AND NRN MS BENEATH A
PLUME OF 6.5 C/KM MID LEVEL LAPSE RATES RESULTING IN AT LEAST
500-1000 J/KG MLCAPE.

STORMS ARE EXPECTED TO DEVELOP WITHIN PRE-FRONTAL CONFLUENCE BAND
ACROSS CNTRL/ERN OK INTO NCNTRL/NERN TX EARLY TUESDAY AND SHIFT EWD
AND NEWD DURING THE DAY. OTHER STORMS MAY DEVELOP FARTHER SOUTH
THROUGH ERN TX DURING THE AFTERNOON ALONG MERGING PACIFIC FRONT AND
SHIFT EWD THROUGH THE LOWER MS VALLEY. THE BOUNDARY LAYER WILL
MOISTEN SUFFICIENTLY FOR THIS ACTIVITY TO BECOME SFC BASED. STORMS
WILL BE EMBEDDED WITHIN STRONG DEEP LAYER FLOW WITH A 50+ KT SLY LLJ
AND MID LEVEL WINDS INCREASING TO 80 KT. STORMS ARE EXPECTED TO
EVOLVE INTO A PREDOMINANT QLCS WITH EMBEDDED SUPERCELL AND BOWING
SEGMENTS POSING A RISK FOR DAMAGING WIND AND TORNADOES. TORNADO
THREAT MAY INCREASE OVERNIGHT...ESPECIALLY IN MODERATE RISK AREA
WHERE LLJ INTENSIFYING TO IN EXCESS OF 70 KT WILL BE COLLOCATED WITH
NRN EDGE OF MID 60S DEWPOINTS.

...UPPER MS VALLEY THROUGH TN VALLEY REGION...

OTHER STORMS WILL EXPAND NEWD THROUGH THE MID MS VALLEY AND SWRN
PARTS OF OH VALLEY WHERE INSTABILITY WILL BE MORE LIMITED...BUT
SUFFICIENT FOR A THREAT FOR DAMAGING WIND WITH PRIMARY MODE BEING
LINES AND BOWING SEGMENTS WITH MESO VORTICES. A FEW EMBEDDED
SUPERCELLS WILL ALSO BE POSSIBLE GIVEN SIZE OF HODOGRAPHS AND
STRENGTH OF DEEP LAYER FLOW/SHEAR SUGGESTING A FEW TORNADOES CANNOT
BE RULED OUT.

..DIAL.. 01/28/2013

[cycloneye]

Dr Greg Forbes Torcon Index

Dr. Greg Forbes Torcon Index
Tuesday, Jan. 29

Severe thunderstorms, possibly in a squall line, in north-central and east TX, east half OK, extreme southeast KS, south and central MO, central and south IL, AR, west and north LA, west KY, west TN, northwest MS.

AL north night - 4
AL west-central, southwest night - 3 to 4
AR east - 4
AR central, west - 3
FL west panhandle night - 3
IL central, south - 3
KS southeast - 3
KY west - 3
KY central night - 3
LA north - 4
LA west-central, southwest - 3
LA night - 3 to 4
MO central, south - 3
MS northwest - 4
MS night - 4
OK central, east - 3
TN west, middle night - 4
TX central, east - 3
other areas - 1 or less
Wednesday, Jan. 30

Severe thunderstorms, possibly in a squall line, in east KY, east half TN, south OH, south WV, central and south VA, NC, SC, GA, northeast, central and south AL, FL panhandle, extreme southeast MS and LA (morning).

AL northeast, central, south - 3
FL panhandle - 3
GA - 3
KY east - 3
LA extreme southeast morning -3
MS extreme southeast morning - 3
NC - 3
OH south - 3
SC - 3
TN east half - 3
VA central, south - 3
WV south half - 3
other areas - 1 or less

[cycloneye]

Day 1 outlook


DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0638 PM CST MON JAN 28 2013

VALID 290100Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
PLAINS...

...NW TX/WRN AND CNTRL OK/SE KS/WRN MO...
AN UPPER-LEVEL TROUGH OVER THE INTERMOUNTAIN WEST WILL MOVE EWD
ACROSS THE FOUR CORNERS REGION TONIGHT. AHEAD OF THE SYSTEM...A
WELL-DEVELOPED LOW-LEVEL JET ACROSS THE SRN PLAINS WILL TRANSPORT
MOISTURE NWD INTO CNTRL OK...SE KS AND WRN MO TONIGHT. ISOLATED
THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE FROM LATE THIS EVENING
INTO THE OVERNIGHT PERIOD FROM NE OK NNEWD ACROSS SE KS INTO WRN MO
ALONG THE WRN EDGE OF THE LOW-LEVEL JET. THIS ACTIVITY COULD POSE A
MARGINAL THREAT FOR WIND DAMAGE AND HAIL DUE TO THE STRONG SHEAR
ENVIRONMENT IN PLACE. FURTHER TO THE SOUTH ACROSS NW TX AND CNTRL
OK...THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE LATE TONIGHT DUE TO
INCREASING LIFT ASSOCIATED WITH AS AN 80 TO 100 KT MID-LEVEL JET
MOVING INTO THE SRN PLAINS.

FORECAST SOUNDINGS TONIGHT IN CNTRL OK GRADUALLY INCREASE
INSTABILITY TONIGHT WITH MLCAPE VALUES APPROACHING 1000 J/KG BY THE
09Z TO 12Z TIMEFRAME. THE INSTABILITY WILL COMPLIMENT A STRONGLY
SHEARED ENVIRONMENT WITH 0-6 KM SHEAR INCREASING TO AROUND 70 KT AS
THE MID-LEVEL JET APPROACHES THE REGION FROM THE SOUTHWEST. THE
STRONG SHEAR WILL LIKELY SUPPORT STORM ROTATION AS CELLS INITIATE
LATE TONIGHT AND SPREAD EWD ACROSS THE SRN PLAINS. ALTHOUGH THE
STORMS MAY BE SOMEWHAT ELEVATED...A THREAT FOR ISOLATED HAIL AND
WIND DAMAGE MAY DEVELOP ESPECIALLY IF A CLUSTER OF STRONG
THUNDERSTORMS CAN ORGANIZE BY 12Z AS IS SUGGESTED BY THE GFS MODEL.

...NRN MO/ERN IA/WRN IL AND FAR SW WI...
A WELL-DEVELOPED 55 TO 65 KT LOW-LEVEL JET WILL STRENGTHEN TONIGHT
ACROSS MO AND IA HELPING MOISTURE TO GRADUALLY INCREASE ACROSS THE
REGION. MODEL FORECASTS DEVELOP SCATTERED THUNDERSTORMS LATE THIS
EVENING FROM NRN MO NEWD ACROSS ERN IA ON THE NOSE OF THE LOW-LEVEL
JET AND SPREAD THIS CONVECTION NEWD ACROSS THE MID TO UPPER MS
VALLEY DURING THE OVERNIGHT PERIOD. FORECASTS SOUNDINGS IN ERN IA AT
06 TO 09Z INCREASE MUCAPE VALUES TO AROUND 1500 J/KG WITH THE
INSTABILITY CONCENTRATED ABOVE 850 MB DUE TO A SHARP SFC INVERSION.
FOR THIS REASON...THE WIND DAMAGE THREAT SHOULD BE LIMITED BUT A
THREAT FOR HAIL COULD EXIST ESPECIALLY WITH CELLS CAN DEVELOP
ROTATION.

..BROYLES.. 01/29/2013

[cycloneye]

Updated outlook of the Moderate Risk area

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1201 AM CST TUE JAN 29 2013

VALID 291200Z - 301200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF SE MO...FAR WRN
TN...AR...NW MS...NRN LA AND FAR NE TX...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
PLAINS...CNTRL PLAINS...MID MS VALLEY....LOWER MS VALLEY...OH VALLEY
AND TN VALLEY...

...SRN PLAINS/ARKLATEX/LOWER TO MID MS VALLEY...
AN UPPER-LEVEL TROUGH OVER THE ROCKIES WILL MOVE EWD INTO THE GREAT
PLAINS TODAY AS A POWERFUL 90 TO 110 KT MID-LEVEL JET OVERSPREADS
THE SRN AND CNTRL PLAINS. AS THE EXIT REGION OF THE MID-LEVEL JET
CORE MOVES ACROSS THE SRN PLAINS THIS MORNING...THUNDERSTORMS APPEAR
LIKELY TO DEVELOP FROM SE KS SWWD ACROSS CNTRL OK INTO NORTH TX.
THIS ACTIVITY SHOULD DEVELOP A SEVERE THREAT AROUND DAYBREAK AS A
BAND OF LARGE-SCALE ASCENT MOVES INTO THE SRN PLAINS AHEAD OF THE
APPROACHING UPPER-LEVEL SYSTEM. CONVECTIVE COVERAGE SHOULD QUICKLY
INCREASE THIS MORNING WITH A SQUALL-LINE DEVELOPING AND MOVING EWD
ACROSS THE OZARKS AND ARKLATEX REGION THIS AFTERNOON. CONDITIONS
WILL BE FAVORABLE FOR SEVERE STORMS ACROSS A LARGE AREA AND A
SIGNIFICANT SEVERE WEATHER EVENT APPEARS LIKELY TO OCCUR LATE THIS
AFTERNOON FROM SERN MO SWWD ACROSS AR INTO NRN LA.

FORECAST SOUNDINGS THIS AFTERNOON FROM NEAR THE BOOTHEEL OF MO SWWD
TO LITTLE ROCK AND SHREVEPORT INCREASE SFC TEMPS INTO THE LOWER 70S
F ALLOWING FOR INSTABILITY TO APPROACH MODERATE LEVELS. IN
ADDITION...DEEP LAYER SHEAR WILL BECOME STRONG AS THE RIGHT SIDE OF
THE MID-LEVEL JET APPROACHES THE REGION FROM THE WEST LATE THIS
AFTERNOON. 0-6 KM SHEAR VALUES OF 60 TO 70 KT ALONG WITH LONG LOOPED
HODOGRAPHS SHOULD SUPPORT SUPERCELL AND TORNADO DEVELOPMENT. THE
GREATEST TORNADO THREAT SHOULD EXIST WITH DISCRETE CELLS THAT
INITIATE AHEAD OF THE SQUALL-LINE FROM SE MO EXTENDING SWD ACROSS
ECNTRL AR WHERE A FEW SIGNIFICANT TORNADOES WILL BE POSSIBLE.
TORNADOES WILL ALSO BE POSSIBLE WITH BOWS AND ROTATING STORMS
EMBEDDED IN THE SQUALL-LINE ITSELF. WINDS JUST ABOVE THE SFC ARE
FORECAST TO BE AROUND 50 KT SUGGESTING THE LINE WILL BE VERY
EFFICIENT AT PRODUCING WIND DAMAGE. SOME DAMAGING WIND GUSTS ABOVE
70 KT MAY OCCUR ACROSS THE SLIGHT AND MODERATE RISK AREA WITH THE
GREATEST THREAT IN ECNTRL AR WHERE THE GFS SUGGESTS THE APEX OF A
LARGE-SCALE BOW COULD DEVELOP. MODEL FORECASTS MOVE THE SQUALL-LINE
EWD ACROSS THE TN VALLEY AND CNTRL GULF COAST STATES AFTER 06Z
SUGGESTING A WIND DAMAGE AND TORNADO THREAT WILL PERSIST THROUGH
MUCH OF THE NIGHT.

...MID MS VALLEY/LOWER OH VALLEY....
AN UPPER-LEVEL TROUGH WILL MOVE INTO THE GREAT PLAINS TODAY AS A 90
TO 110 KT MID-LEVEL JET TRANSLATES EWD INTO THE SRN AND CNTRL
PLAINS. THUNDERSTORMS SHOULD DEVELOP ACROSS ERN KS AND WRN MO THIS
MORNING WITH CONVECTION RAPIDLY EXPANDING NEWD ACROSS THE MID MS
VALLEY AROUND MIDDAY. AS THE EXIT REGION OF THE MID-LEVEL JET
OVERSPREADS THE REGION THIS AFTERNOON...SQUALL-LINE DEVELOPMENT
SHOULD OCCUR ACROSS CNTRL MO WITH A WELL-DEVELOPED LINE-SEGMENT
MOVING EWD ACROSS THE VICINITY OF ST LOUIS EARLY THIS EVENING.
FORECAST SOUNDINGS AT 03Z IN THE VICINITY OF ST LOUIS INCREASE
SBCAPE TO AROUND 1000 J/KG AS 0-6 KM SHEAR REACHES 60 KT. THIS ALONG
WITH VERY STRONG LOW-LEVEL FLOW EXCEEDING 70 KT SHOULD BE FAVORABLE
FOR WIND DAMAGE. A SPLIT MID-LEVEL JET STRUCTURE IMPLIES THAT LIFT
WILL BE VERY STRONG HELPING TO ORGANIZE A WELL-DEVELOP SQUALL-LINE.
THIS LINE IS FORECAST TO MOVE EWD ACROSS THE LOWER OH VALLEY TONIGHT
WHERE THERE WILL BE A POTENTIAL FOR DAMAGING WIND GUSTS AND
TORNADOES EVEN INTO THE OVERNIGHT HOURS.

..BROYLES/MOSIER.. 01/29/2013

[WeatherGuesser]

Moderate zone expanded.

Prospects for going High?

[cycloneye]

Updated Outlook by SPC at 12:50z

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0650 AM CST TUE JAN 29 2013

VALID 291300Z - 301200Z

...THERE IS A MDT RISK OF SVR TSTMS THIS EVENING INTO TONIGHT FOR
MUCH OF AR...FAR NERN TX...FAR NRN LA...WEST CENTRAL AND NW MS...FAR
SWRN TN AND PART OF SERN MO...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM
THE SRN PLAINS TO CENTRAL GULF COAST STATES AND NNEWD INTO THE MID
MS AND LOWER OH VALLEYS...

...SYNOPSIS...
A DEEP LONGWAVE TROUGH...CURRENTLY CENTERED OVER THE ROCKIES INTO
NRN MEXICO PER WATER VAPOR IMAGERY...WILL CONTINUE TO SHIFT E TOWARD
THE PLAINS STATES THIS FORECAST PERIOD. A STRONG SHORTWAVE TROUGH
WILL EJECT NEWD FROM THE BASE OF THE LONGWAVE TROUGH THROUGH THE SRN
PLAINS...REACHING THE LOWER MO/MID MS VALLEYS LATER TONIGHT/EARLY
WED MORNING. A STRONG 90-100 KT SWLY MIDLEVEL JET WILL ACCOMPANY
THE LEAD SHORTWAVE TROUGH. FURTHER STRENGTHENING OF THIS SWLY WIND
FIELD IS EXPECTED DURING THE SECOND HALF OF THE PERIOD FROM CENTRAL
TX THROUGH AR TO THE LOWER OH VALLEY. THIS WILL OCCUR AS A STRONG
UPSTREAM JET OVER THE PACIFIC NW TO GREAT BASIN TRANSLATES THROUGH
THE BASE OF THE PARENT LONGWAVE TROUGH AND EMERGES ACROSS TX TO THE
LOWER OH VALLEY THIS EVENING AND TONIGHT.

EARLY MORNING SURFACE ANALYSIS SHOWED A SYNOPTIC LOW CENTERED OVER
IA WITH A POLAR FRONT EXTENDING SSWWD THROUGH FAR NWRN MO...ERN KS
TO NWRN OK...AND THEN WWD THROUGH THE OK PANHANDLE TO AN AREA OF LOW
PRESSURE IN SERN CO. A WARM FRONT EXTENDED EWD FROM IA ALONG THE
IL/WI BORDER TO N OF CHICAGO INTO FAR NRN OH. MEANWHILE...A DRY
LINE EXTENDED SWD ACROSS FAR WRN OK TO THE TX BIG BEND REGION TO THE
NW OF DRT...WITH A PACIFIC COLD FRONT EXTENDING SWD THROUGH THE TX
PANHANDLE AND W TO SW TX. PRIOR THE PACIFIC NW/GREAT BASIN JET
EMERGING ENE OF THE SWRN STATES...THE POLAR FRONT AND DRY LINE WILL
MOVE SLOWLY EWD...WHILE THE WARM FRONT MOVES NWD THROUGH SERN WI AND
LOWER MI. BY THIS EVENING...THE PACIFIC FRONT WILL OVERTAKE THE DRY
LINE AND ADVANCE MORE QUICKLY EWD...CONCURRENT WITH THE ADVANCEMENT
OF THE POLAR FRONT. BY 12Z WED...A SYNOPTIC LOW SHOULD BE LOCATED
OVER LOWER MI WITH COLD FRONT EXTENDING SSWWD THROUGH INDIANA TO
MIDDLE TN...MS...SERN LA TO THE WRN GULF.

...SRN PLAINS TO CENTRAL GULF COAST STATES TO MID MS AND LOWER OH
VALLEYS...
A MOIST AIR MASS ALREADY IN PLACE ACROSS THE SRN PLAINS IS
SUPPORTING AN INCREASINGLY UNSTABLE ENVIRONMENT WITH MLCAPE UP TO
1000 J/KG EXTENDING FROM NORTH TX INTO CENTRAL OK...ALONG AND EAST
OF THE DRY LINE. STRONG HEIGHT FALLS SPREADING EWD WITH THE LONGWAVE
TROUGH AND LEAD SHORTWAVE TROUGH MOVING ENEWD THROUGH THE SRN HIGH
PLAINS HAS SUPPORTED THE ONSET OF STRONG TO SEVERE ORGANIZED STORMS
PRIOR TO THE START OF DAY 1 OVER WRN OK. THIS INCREASE IN DEEP
LAYER ASCENT IS ALSO EVIDENT FARTHER TO THE NORTHEAST JUST AHEAD OF
THE POLAR FRONT IN NRN OK TO SERN KS AND SWRN MO WHERE STORMS HAVE
BEEN INCREASING IN COVERAGE AND INTENSITY SINCE 10-11Z. THE TORNADO
AND DAMAGING WIND PROBABILITIES AND SLIGHT RISK AREA HAVE BEEN
EXTENDED WWD TO INCLUDE MORE OF NORTHWEST TX...WRN AND NRN OK INTO
ERN KS. THIS CHANGE IS DUE TO THE ONGOING STRONG TO SEVERE STORMS
AND THE LIKELIHOOD FOR ADDITIONAL ACTIVITY WITH SWD AND NEWD EXTENT
ALONG THE DRY LINE AND POLAR FRONT...RESPECTIVELY.

STRONG-EXTREME HEIGHT FALLS SPREADING FROM THE SRN/CENTRAL PLAINS TO
THE MS RIVER VALLEY TODAY/TONIGHT WILL RESULT IN A RELATIVELY BROAD
SSWLY LLJ UNDERGOING STRENGTHENING AS IT SHIFTS ENEWD AHEAD OF THE
POLAR FRONT/DRY LINE. THIS WILL ALLOW MOISTURE TO SPREAD FAIRLY FAR
N FOR THIS TIME OF YEAR...WITH SURFACE DEWPOINTS IN THE UPPER 50S TO
NEAR 60 F REACHING NRN IL AND INDIANA. FARTHER S...MID 60S DEWPOINTS
WILL SPREAD INTO SERN OK...CENTRAL AR TO WRN TN THIS AFTERNOON
THROUGH TONIGHT.

MODEST MIDLEVEL LAPSE RATES WITH NWD EXTENT WILL TEND TO LIMIT THE
DEVELOPMENT OF STRONGER INSTABILITY...ESPECIALLY INTO THE LOWER MO
AND MID MS VALLEYS. MODIFIED FORECAST SOUNDINGS INTO NRN IL SUGGEST
THE POTENTIAL FOR MUCAPE AROUND 400 J/KG THIS AFTERNOON. FARTHER
S...MIDLEVEL LAPSE RATES CLOSER TO 8 C/KM PER 12Z SOUNDING AT FORT
WORTH TEXAS IS SUPPORTING THE AFOREMENTIONED MUCAPE TO AROUND 1000
J/KG EXTENDING INTO CENTRAL OK. SIMILAR MUCAPE VALUES ARE EXPECTED
INTO NERN TX/SERN OK TO SRN AR WHERE GREATER MOISTURE IS FORECAST
THIS AFTERNOON AND EVENING.

STRENGTHENING DEEP LAYER WIND FIELDS WITH EFFECTIVE BULK SHEAR
EXCEEDING 50 KT AS FAR N AS THE LOWER MO TO LOWER OH VALLEYS AND
SHEAR VECTORS ORIENTED NEARLY PARALLEL TO THE POLAR FRONT AND DRY
LINE SUGGEST PRIMARILY A LINEAR STORM MODE. HOWEVER...GIVEN THE
STRENGTH OF THE BULK SHEAR AND INCREASING LOW LEVEL HODOGRAPH
CURVATURE...TORNADOES WILL BE POSSIBLE IN ADDITION TO DAMAGING
WINDS. MODELS CONTINUE TO INDICATE A STRONG INCREASE IN DEEP LAYER
WINDS AS THE UPSTREAM PACIFIC NW/GREAT BASIN JET ADVANCES INTO THE
SRN EXTENT OF THE OUTLOOK AREA INCLUDING THE MODERATE RISK. THIS
WILL FURTHER INCREASE LOW LEVEL SHEAR/HODOGRAPH CURVATURE FOR AN
ENHANCED THREAT FOR STRONGER TORNADOES INCLUDING THE METRO AREAS OF
LITTLE ROCK AND MEMPHIS AFTER DARK THIS EVENING/TONIGHT. GIVEN THE
STRENGTHENING DEEP LAYER SSWLY WINDS TONIGHT ACROSS A MODESTLY
UNSTABLE WARM SECTOR...MODELS CONTINUE TO ADVERTISE THE DEVELOPMENT
OF A WELL DEFINED QLCS ADVANCING E OF THE MID-LOWER MS RIVER. THIS
SCENARIO IS ALSO SUPPORTED BY THE 00Z 4KM WRF-NSSL SUGGESTING THE
QLCS WITH A THREAT FOR DAMAGING WINDS AND A FEW TORNADOES REACHES
PARTS OF THE LOWER OH VALLEY TO CENTRAL GULF COAST STATES.
THUS...THE SLIGHT RISK AND SEVERE WIND AND TORNADO PROBABILITIES
HAVE BEEN EXTENDED EWD SOME WITH THIS OUTLOOK ISSUANCE.

THE SLIGHT RISK HAS ALSO BEEN EXTENDED NWD TO INCLUDE THE REST OF
NRN IL TO ACCOUNT FOR A THREAT FOR DAMAGING WINDS AND EVEN A TORNADO
THREAT...GIVEN THE PRESENCE OF FAVORABLE DEEP LAYER AND LOW LEVEL
SHEAR...DESPITE WEAKER INSTABILITY THIS AFTERNOON.

..PETERS/ROGERS.. 01/29/2013

[WeatherGuesser]

PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0409 AM CST TUE JAN 29 2013

...THE MOST SIGNIFICANT THREAT FOR SEVERE THUNDERSTORMS IS EXPECTED
OVER PARTS OF THE OZARK REGION AND THE LOWER MISSISSIPPI VALLEY THIS
EVENING THROUGH TONIGHT...

THE NWS STORM PREDICTION CENTER IN NORMAN OK IS FORECASTING THE
DEVELOPMENT OF DAMAGING WINDS AND A FEW TORNADOES...SOME
STRONG...OVER PARTS OF THE OZARK REGION AND THE LOWER MISSISSIPPI
VALLEY THIS EVENING THROUGH TONIGHT.

THE AREAS MOST LIKELY TO EXPERIENCE THIS ACTIVITY INCLUDE

MUCH OF SOUTHERN...CENTRAL AND EASTERN ARKANSAS
FAR NORTHERN LOUISIANA
FAR SOUTHEAST MISSOURI
NORTHWEST AND WEST CENTRAL MISSISSIPPI
FAR SOUTHWEST TENNESSEE
FAR NORTHEAST TEXAS

ELSEWHERE...SEVERE STORMS ARE ALSO POSSIBLE FROM...THE SOUTHERN
PLAINS AND THE SRN EXTENT OF THE LOWER MISSISSIPPI VALLEY NORTHWARD
TO THE MIDDLE MISSISSIPPI...TENNESSEE AND LOWER OHIO VALLEYS.

A STRONG STORM SYSTEM TRACKING THROUGH THE SOUTHERN PLAINS TO THE
MIDDLE MISSISSIPPI VALLEY REGION WILL RESULT IN STRENGTHENING WINDS
THROUGH THE LOWER AND MIDDLE TROPOSPHERE. A MOIST AIR MASS WILL
CONTINUE TO SPREAD NORTHWARD TODAY THROUGH TONIGHT AHEAD OF A COLD
FRONT AND DRY LINE ADVANCING EASTWARD. ALTHOUGH THE ENVIRONMENT
SHOULD ONLY BE MARGINALLY UNSTABLE...THE STRENGTH OF THE DEEP LAYER
WINDS WILL SUPPORT A THREAT FOR DAMAGING WINDS AND TORNADOES.

THUNDERSTORMS WILL CONTINUE TO DEVELOP AND SPREAD EAST AND NORTHEAST
THIS MORNING INTO THE AFTERNOON ACROSS OKLAHOMA...PARTS OF NORTH
TEXAS AND EASTERN KANSAS. DAMAGING WINDS AND TORNADOES WILL BE
POSSIBLE WITH THIS ACTIVITY INTO THE AFTERNOON. A MORE SIGNIFICANT
SEVERE WEATHER THREAT IS EXPECTED TO DEVELOP THIS EVENING THROUGH
TONIGHT ACROSS MUCH OF ARKANSAS...FAR NORTHEAST TEXAS...NORTHERN
LOUISIANA...SOUTHEAST MISSOURI INTO WEST CENTRAL AND NORTHWEST
MISSISSIPPI AND PARTS OF FAR WESTERN TENNESSEE WHERE DAMAGING WINDS
AND TORNADOES ARE EXPECTED TO BE MORE WIDESPREAD. THE SEVERE
WEATHER THREAT WILL SPREAD FARTHER EAST LATER TONIGHT INTO PARTS OF
THE CENTRAL GULF COAST STATES...TENNESSEE VALLEY AND POTENTIALLY THE
LOWER OHIO VALLEY...WITH A CONTINUED THREAT FOR DAMAGING WINDS AND A
FEW TORNADOES.

STATE AND LOCAL EMERGENCY MANAGERS ARE MONITORING THIS DEVELOPING
SITUATION. THOSE IN THE THREATENED AREA ARE URGED TO REVIEW SEVERE
WEATHER SAFETY RULES AND TO LISTEN TO RADIO...TELEVISION...AND NOAA
WEATHER RADIO FOR POSSIBLE WATCHES...WARNINGS...AND STATEMENTS LATER
TODAY.

..PETERS.. 01/29/2013




Multimedia Briefing: http://www.spc.noaa.gov/products/outlook/pwo.mp4

[WeatherGuesser]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 5
NWS STORM PREDICTION CENTER NORMAN OK
500 AM CST TUE JAN 29 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

WESTERN AND CENTRAL OKLAHOMA
FAR NORTHWEST TEXAS

EFFECTIVE THIS TUESDAY MORNING FROM 500 AM UNTIL NOON CST.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES SOUTHWEST OF FORT
SILL OKLAHOMA TO 20 MILES NORTH NORTHWEST OF PONCA CITY OKLAHOMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU5).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

DISCUSSION...TSTMS HAVE RECENTLY INTENSIFIED ALONG THE DRYLINE OVER
WRN OK IN RESPONSE TO INCREASING HEIGHT FALLS ASSOCIATED WITH WRN
U.S. TROUGH. THESE STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND
INTENSITY THIS MORNING AS LARGE-SCALE FORCING FOR ASCENT FURTHER
STRENGTHENS...AND AS LOW-LEVEL CONVERGENCE IS ENHANCED BY A
MIGRATORY SURFACE LOW DEVELOPING NEWD ACROSS THE WATCH AREA.
MODEL-DERIVED FORECAST SOUNDINGS INDICATE THAT BOUNDARY LAYER
DEWPOINTS IN THE LOWER 60S ARE CONTRIBUTING TO MLCAPE VALUES OF
500-1000 J/KG WITH LITTLE OR NO CONVECTIVE INHIBITION. WHEN COUPLED
WITH 60 KT OF EFFECTIVE BULK SHEAR AND EFFECTIVE SRH VALUES OF
300-350 M2/S2...THE ENVIRONMENT WILL SUPPORT SUPERCELLS AND BOWING
LINE SEGMENTS CAPABLE OF DAMAGING WINDS AND A FEW TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 400.
MEAN STORM MOTION VECTOR 23045.


...MEAD

[WeatherGuesser]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 6
NWS STORM PREDICTION CENTER NORMAN OK
725 AM CST TUE JAN 29 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

NORTHWEST ARKANSAS
EASTERN KANSAS
WEST-CENTRAL AND SOUTHWEST MISSOURI
NORTHEAST OKLAHOMA

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 725 AM UNTIL
300 PM CST.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 30 MILES SOUTHWEST OF MUSKOGEE
OKLAHOMA TO 15 MILES NORTH NORTHWEST OF KNOB NOSTER MISSOURI.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU6).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 5...

DISCUSSION...A COMPLEX SCENARIO IS UNFOLDING THIS MORNING INVOLVING
A LONG-LIVED BOWING LINE SEGMENT AND INCREASING TSTM DEVELOPMENT
ALONG A COLD FRONT ADVANCING SEWD INTO THE WATCH AREA. CURRENT
THINKING IS THAT THE LINE SEGMENT WILL EVENTUALLY MERGE WITH THE
FRONTAL CONVECTION...RESULTING IN A LARGER-SCALE QLCS WHICH WILL
MOVE RAPIDLY INTO THE OZARK PLATEAU. 12Z OBSERVED SOUNDINGS
INDICATE THAT THE AMBIENT ENVIRONMENT IS ONLY WEAKLY UNSTABLE WITH
MLCAPE OF 500-1000 J/KG. HOWEVER...GIVEN AN INCREASE IN LARGE-SCALE
FORCING FOR ASCENT AND STRONG LOW-LEVEL AND DEEP-LAYER SHEAR...THE
SETUP WILL BE SUPPORTIVE OF EMBEDDED LEWP STRUCTURES CAPABLE OF
DAMAGING WINDS AND TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 23045.


...MEAD

[cycloneye]

From Dr Jeff Masters

Golf-ball sized hail fell at three locations in Oklahoma already this morning, and a wind gust of 75 mph was reported in a thunderstorm near Omega, Oklahoma. NOAA's Storm Prediction Center has placed portions of Arkansas, Louisiana, Mississippi, Tennessee, Missouri, and Texas in their "Moderate Risk" region for severe weather on Tuesday. This is the first "Moderate Risk" forecast issued during 2013. The primary threat will be damaging thunderstorm winds, but we will also see tornadoes, with the potential for a few strong EF-2 and EF-3 twisters.

[CrazyC83]

At some point, it might be time to create a new thread.

New Tornado Watch coming just west of the Moderate Risk area.

[cycloneye]

At some point, it might be time to create a new thread.

New Tornado Watch coming just west of the Moderate Risk area.

Thread has been made to not have all the posting of watches and warnings for this event in this general 2013 thread.

[cycloneye]

If anyone has videos or photos of the January 29-30 severe event,this is the place to post them as the other Jan 29-30 severe event thread is to post watches, warnings and the SPC outlooks.

[cycloneye]

Here are impacting photos that are on twitter. That tornado looks like a 2 or 3.

https://twitter.com/search?q=%23tornado&src=hash

[cycloneye]

These are the stats from January 29.