Mar 18-24 Plains/MW/OV/GL Severe Weather, SPC Risk Level: Day 1 Slight Risk - Forecasts & OBS Options

[The Snowman]

Sig. Tor. Ingredients off SPC SREF 15z run.

Hour 66


Hour 81

[MDH]

Absolutely stunning models for this time of year. Southern Canada could see tornadoes as early as March the 18th at a time of year when they are used to heavy snow or rain.

[andyhb]

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT SAT MAR 17 2012

VALID 181200Z - 191200Z

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

...SYNOPSIS...
WHILE LARGE-SCALE RIDGING ALOFT PREVAILS ACROSS THE ERN HALF OF THE
CONUS...A STRONG/EXPANSIVE TROUGH AFFECTING MOST OF WRN NOAM WILL
ADVANCE SLOWLY EWD ACROSS THE GREAT BASIN AND INTERMOUNTAIN WEST
THIS PERIOD. WHILE REMAINING OVER THE ROCKIES THROUGH THE
PERIOD...HEIGHT FALLS ASSOCIATED WITH THIS SYSTEM WILL BEGIN
OVERSPREADING THE PLAINS THIS PERIOD...SUPPORTING EVENTUAL
DEVELOPMENT OF STRONG/SEVERE CONVECTION E OF THE MOUNTAINS.

AT THE SURFACE...A CONSOLIDATING/STRENGTHENING LOW SHOULD MOVE NEWD
WITH TIME REACHING THE WRN ND VICINITY LATE. A TRAILING N-S COLD
FRONT IS EXPECTED TO MOVE INTO THE HIGH PLAINS DURING THE SECOND
HALF OF THE PERIOD...BUT A PRIMARY FOCUS OF THE MORE ROBUST
CONVECTIVE ACTIVITY WILL LIKELY BE A DRYLINE EXPECTED ACROSS THE
CENTRAL/SRN HIGH PLAINS DURING THE AFTERNOON.

...CENTRAL AND SRN PLAINS...
SHOWERS AND THUNDERSTORMS -- LIKELY HIGH-BASED -- ARE FORECAST TO
DEVELOP DURING THE AFTERNOON ATOP A CAPPED BOUNDARY LAYER OVER THE
SRN PLAINS...AS A LEAD WAVE SHIFTS ACROSS THE REGION IN ADVANCE OF
THE LARGER-SCALE SYSTEM. ATTM...IT APPEARS THAT LITTLE IF ANY
SEVERE THREAT WILL ACCOMPANY THIS CONVECTION...AS IT SPREADS ACROSS
PARTS OF CENTRAL AND E TX/OK/KS AND INTO MO/AR THROUGH THE AFTERNOON
AND EVENING.

MEANWHILE...A MORE POTENT SEVERE WEATHER ENVIRONMENT SHOULD BE
EVOLVING ACROSS THE CENTRAL AND SRN HIGH PLAINS...AS HEATING AHEAD
OF A SURFACE DRYLINE RESULTS IN MODERATE DESTABILIZATION. AS HEIGHT
FALLS SPREAD SLOWLY EWD ATOP THE DRYLINE...INCREASING ASCENT --
FOCUSED ALONG THE SURFACE BOUNDARY -- SHOULD RESULT IN
ISOLATED/AFTERNOON STORM DEVELOPMENT. WITH TIME...COVERAGE OF
CONVECTION SHOULD INCREASE -- PARTICULARLY THROUGH THE EVENING AS
SLIGHT NEGATIVE TILTING OF THE MAIN UPPER TROUGH RESULTS IN STRONGER
ASCENT OVERSPREADING THE AREA AFTER DARK.

AS THE SYSTEM SHIFTS EWD...FLOW ALOFT WILL CONTINUE TO INCREASE.
WHILE INCREASINGLY MERIDIONAL WITH NWD EXTENT...SSWLY FLOW AT MID
LEVELS FROM ROUGHLY KS SWD ATOP SSELY BOUNDARY LAYER FLOW AHEAD OF
THE DRYLINE WILL RESULT IN A FAVORABLY-SHEARED
ENVIRONMENT...SUPPORTIVE OF RAPIDLY STRENGTHENING SUPERCELL STORMS.
WHILE ISOLATED INITIALLY...THE RELATIVELY NARROW CORRIDOR OF
GREATEST THREAT SUPPORTS MAINTENANCE OF A HIGHER-END SLIGHT RISK --
WITH VERY LARGE HAIL AND LOCALLY DAMAGING WINDS THE MAIN THREATS.

..GOSS.. 03/17/2012

[Illinois blizzar...]

Reed Timmer: Meteorologist and Extreme Storm Chaser

Now this is a scary hodograph. From eastern AR with 70 knots at 1 km. See how long that vector is from the surface to just above? This low-level shear vector is about as large as they get.

[rifej7386]

This system has the potential to be very nasty all the way to the East Coast. It will have plenty of warm moist air to work with and it appears substantial wind shear. I pray we don't see Long Track Tornadoes in populated areas but it appears that could very well happen. There is a price to pay for a mild Winter and 2 weeks of 70*+ temps in Early/Mid March. Mother Nature is fickle right now and she is about to throw a temper tantrum. Everybody stay Weather Alert.

[MichelleOH]

How far north is this system supposed to get? Ohio?

[rifej7386]

How far north is this system supposed to get? Ohio?

That is yet to be determined. It will be day to day since we are dealing with a lazy Cut-Off Low and a strong EC Ridge.

[MichelleOH]

Thanks!

[WeatherMonger]

Hopefully the Intellicast forecast is on to something.

Details for Wednesday, March 21
Showers and thunderstorms. Potential for severe thunderstorms. Highs in the low 70s and lows in the mid 50s.

ILX HWO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
547 AM CDT SUN MAR 18 2012


THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS...EAST CENTRAL ILLINOIS AND SOUTHEAST ILLINOIS.



.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

A SLOW-MOVING STORM SYSTEM WILL BRING A PROLONGED PERIOD OF
THUNDERSTORM CHANCES INTO CENTRAL ILLINOIS FROM TUESDAY NIGHT THROUGH
FRIDAY NIGHT. AT THIS TIME...IT APPEARS THE GREATEST CHANCE FOR STORMS
WILL DEVELOP ON WEDNESDAY AND THURSDAY. WIDESPREAD SEVERE WEATHER
IS NOT ANTICIPATED.

BAK

AFD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
700 AM CDT SUN MAR 18 2012

LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT

STRONG UPPER LEVEL DISTURBANCE NEAR THE CA COAST TO EVOLVE INTO A
STRONG CUTOFF LOW THAT MOVES INTO THE MID MS VALLEY LATE THIS
WEEK. MODELS HAVE OVERALL TRENDED SLOWER WITH THIS FEATURE WITH
STRONG UPPER LEVEL RIDGE OVER THE EASTERN STATES HOLDING OUT
LONGER. SO WARMED UP HIGHS WED A FEW MORE DEGREES AND HAVE POPS
RANGING FROM 20% NEAR THE INDIANA BORDER WED TO 60% FROM PEORIA
AND SPRINGFIELD WEST BY WED AFTERNOON. GOOD CHANCES OF SHOWERS AND
THUNDERSTORMS WED NIGHT THROUGH THU NIGHT THEN HIGHEST POPS
GRADUALLY SHIFT EAST FRI AND FRI NIGHT WITH CUTOFF LOW. COOLING
TEMPS DURING 2ND HALF OF THE WEEK BUT STILL REMAINING ABOVE NORMAL
FOR LATE MARCH WITH HIGHS NEXT WEEKEND IN THE UPPER 50S AND LOWER
60S AND LOWS STAYING ABOVE FREEZING.

HUETTL

[jdrenken]

Sorry that I haven't been able to contribute, but it's been a little hectic around here.

Don't forget about the NSSL website with various experimental radars in the prime zone.

[jdrenken]

Various parameters are getting primed between Lubbock and Memphis, TX. Looking at surface OBS, my thought would be Childress is the spot to be.

[WeatherMonger]

Looks like a significant flood threat will be an issue as well, probably needs a thread. Days 1-3 and 5 day totals respectively

[jdrenken]

MESOSCALE DISCUSSION 0273
NWS STORM PREDICTION CENTER NORMAN OK
0231 PM CDT SUN MAR 18 2012

AREAS AFFECTED...ERN OK/TX PANHANDLES...FAR WRN OK...WRN N TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 181931Z - 182130Z

THE SEVERE THREAT WILL INCREASE OVER THE NEXT 1-3 HOURS AND
THUNDERSTORMS ARE EXPECTED TO INITIATE AROUND 21Z. LARGE HAIL WILL
BE THE MAIN THREAT BUT A FEW TORNADOES WILL ALSO BE POSSIBLE. A WW
WILL LIKELY BE NEEDED WITHIN THE NEXT HOUR OR SO.

19Z VIS SAT IMAGERY SHOWED CUMULUS BEGINNING TO DEVELOP ACROSS THE
TX S PLAINS E OF LBB AHEAD OF A DRYLINE EXTENDING SWD FROM WRN KS
THROUGH SWRN TX. AS TEMPERATURES HAVE WARMED INTO THE MID AND UPPER
70S THIS AFTERNOON...ONLY WEAK MLCIN REMAINS WITH MLCAPE VALUES NOW
APPROACHING 2000 J/KG. WITH ADDITIONAL HEATING REMAINING CAP WILL
QUICKLY ERODE AND CONVECTIVE INITIATION IS EXPECTED WITHIN THE NEXT
COUPLE OF HOURS. WHILE THE MAIN UPPER LEVEL FORCING REMAINS WELL TO
THE WEST ACROSS AZ/NM WITH THE UPPER LEVEL TROUGH...HEIGHT FALLS
HAVE BEEN OCCURRING ACROSS THE REGION THIS AFTERNOON AND RECENT
PROFILER DATA HAVE INDICATED AN INCREASE IN MIDLEVEL FLOW STREAMING
INTO THE MCD AREA. GIVEN BULK SHEAR VALUES OF 35-45 KTS AND MIDLEVEL
LAPSE RATES AROUND 7.5 DEG C/KM...ORGANIZED SUPERCELL STORMS CAPABLE
OF LARGE HAIL ARE EXPECTED. WHILE LARGE HAIL WILL INITIALLY BE THE
MAIN THE THREAT...AS THE UPPER TROUGH MOVES EWD AND STRONGER DEEP
LAYER FORCING ENCROACHES UPON THE REGION TOWARD 00Z...LOW LEVEL
HODOGRAPHS WILL BECOME MORE FAVORABLE FOR TORNADO DEVELOPMENT.
THEREFORE...A TORNADO WATCH WILL LIKELY BE ISSUED.

..LEITMAN.. 03/18/2012

[jdrenken]

[jdrenken]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 80
NWS STORM PREDICTION CENTER NORMAN OK
315 PM CDT SUN MAR 18 2012

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

FAR WESTERN OKLAHOMA AND THE EASTERN OKLAHOMA PANHANDLE
PARTS OF WEST CENTRAL/NORTHWEST INTO THE EASTERN TEXAS
PANHANDLE
PANHANDLE

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 315 PM UNTIL
1000 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH NORTHWEST OF
GAGE OKLAHOMA TO 45 MILES WEST SOUTHWEST OF ABILENE TEXAS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU0).

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...VISIBLE SATELLITE IMAGERY SHOWS DEEPENING CUMULUS ALONG
AND E OF THE DRYLINE FROM BIG SPRING TX NWD THROUGH THE CENTRAL/ERN
TX PANHANDLE...WITH THE MOST LIKELY AREA FOR STORM DEVELOPMENT
BETWEEN CHILDRESS AND BIG SPRING BY 21Z. THE STORM ENVIRONMENT IS
BECOMING MORE FAVORABLE FOR SUPERCELLS AS BOTH DEEP-LAYER AND
LOW-LEVEL SHEAR INCREASE IN CONJUNCTION WITH DAYTIME HEATING/
DESTABILIZATION. VERY LARGE HAIL WILL BE POSSIBLE WITH ANY OF THE
SUSTAINED SUPERCELLS THROUGH THE EVENING...AND A FEW TORNADOES WILL
ALSO BE POSSIBLE GIVEN TEMPERATURE-DEWPOINT SPREADS GENERALLY AOB 20
F AND INCREASING EFFECTIVE SRH THROUGH THE EVENING.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24030.

...THOMPSON

[jdrenken]

VIL of 50 on the Childress storm. Should go severe soon.

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LUBBOCK TX
346 PM CDT SUN MAR 18 2012

THE NATIONAL WEATHER SERVICE IN LUBBOCK HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN HALL COUNTY IN THE PANHANDLE OF TEXAS.
SOUTHWESTERN CHILDRESS COUNTY IN THE PANHANDLE OF TEXAS.
NORTHERN COTTLE COUNTY IN NORTHWEST TEXAS.

* UNTIL 445 PM CDT

* AT 345 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR
CEE VEE...OR 16 MILES NORTHWEST OF PADUCAH...AND MOVING NORTHEAST
AT 30 MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE TELL...CHILDRESS
AND KIRKLAND.

[jdrenken]

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LUBBOCK TX
409 PM CDT SUN MAR 18 2012

THE NATIONAL WEATHER SERVICE IN LUBBOCK HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
KING COUNTY IN NORTHWEST TEXAS.
SOUTHEASTERN COTTLE COUNTY IN NORTHWEST TEXAS.

* UNTIL 500 PM CDT

* AT 407 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR
GUTHRIE...AND MOVING NORTHEAST AT 35 MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE GROW...CHALK AND
HACKBERRY.

[beninbaltimore]

Storms are blowing up very quickly

[The Snowman]

Here we go...

Attached thumbnail(s)

 

[rifej7386]

Rotation SW of Dublin and close to Westerville.