STORM2K

SPC AC 170730

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT SUN APR 17 2011

VALID 191200Z - 201200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE MIDWEST/OH
RIVER VALLEY TO EASTERN OK/ARKLATEX...

...MIDWEST AND OH/MIDDLE MS RIVER VALLEYS TO THE SOUTHERN
PLAINS/ARKLATEX...

A VERY ACTIVE SEVERE WEATHER DAY IS EXPECTED ACROSS THE REGION ON
TUESDAY...INCLUDING THE POSSIBILITY OF TORNADOES/LARGE HAIL AND
DAMAGING WINDS ESPECIALLY TUESDAY AFTERNOON/NIGHT.

INITIALLY...ELEVATED EARLY DAY TSTMS /SOME CAPABLE OF SEVERE HAIL/
WILL BE ONGOING ACROSS THE MIDWEST/OH RIVER VALLEY ON THE EDGE OF A
NORTHEASTWARD BUILDING ELEVATED MIXED LAYER. OTHERWISE...BENEATH THE
BUILDING CAP...LOW LEVEL MOISTURE WILL AGGRESSIVELY ADVECT
NORTHEASTWARD AS STRONG SOUTHWESTERLY LOW LEVEL WINDS ARE MAINTAINED
THROUGH THE DAY. ACCORDINGLY...LOWER TO MIDDLE 60S F SURFACE
DEWPOINTS WILL BECOME INCREASINGLY ESTABLISHED TO THE EAST OF A
LOWER MO VALLEY SURFACE LOW AND ALONG/SOUTH OF A NORTHWARD MOVING
WARM FRONT ACROSS THE OH RIVER VALLEY/MIDWEST. BENEATH THE STRONG
EML/PLUME OF STEEP MID LEVEL LAPSE RATES...MODERATELY TO STRONG
INSTABILITY WILL LIKELY EXIST ACROSS THE PRE-COLD FRONT WARM SECTOR
BY AFTERNOON...WITH UPWARDS OF 2000-4000 J/KG OF MLCAPE POSSIBLE.

AIDED BY A NORTHEASTWARD ADVANCING SHORTWAVE TROUGH/ASSOCIATED
HEIGHT FALLS...TSTMS SHOULD ERUPT BY MID/LATE AFTERNOON INTO EARLY
EVENING AHEAD OF A DEEPENING LOWER MO VALLEY/MIDDLE MS VALLEY
SURFACE LOW AND NORTHEAST-SOUTHWEST ORIENTED COLD FRONT. SUCH
VIGOROUS DEEP CONVECTIVE DEVELOPMENT CURRENTLY APPEARS MOST PROBABLE
TO INITIALLY OCCUR ACROSS EASTERN/SOUTHERN MO INTO WESTERN IL...AND
A BIT LATER ACROSS EASTERN OK/NORTHWEST AR IN VICINITY OF THE
DRYLINE.

AMPLE LOW LEVEL MOISTURE/VERY STRONG LAPSE RATES AND DEEP LAYER
SHEAR OF 35-45 KT COINCIDENT WITH THE COLD FRONT/NEARBY WARM SECTOR
WILL BE FURTHER ACCENTUATED BY LONG/CURVING LOW LEVEL HODOGRAPHS
AIDED BY 40-55 KT WINDS WITHIN THE LOWEST 1-2 KM. THUS...INITIAL
MODE SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES CAN BE
EXPECTED...WITH MORE OF A DAMAGING WIND AND ISOLATED TORNADO THREAT
EVOLVING DURING THE EVENING AS SUBSEQUENT QUASI-LINEAR BOW
DEVELOPMENT OCCURS.

PORTIONS OF THE REGION WILL LIKELY NEED TO BE UPGRADED TO A MODERATE
RISK IN SUBSEQUENT DAY 2 OUTLOOKS.

..GUYER.. 04/17/2011

CLICK TO GET WUUS03 PTSDY3 PRODUCT

000
FLUS43 KPAH 170839
HWOPAH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PADUCAH KY
339 AM CDT SUN APR 17 2011

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-
100-107>112-114-180845-
JEFFERSON-WAYNE IL-EDWARDS-WABASH-PERRY IL-FRANKLIN-HAMILTON-
WHITE-JACKSON-WILLIAMSON-SALINE-GALLATIN-UNION IL-JOHNSON-POPE-
HARDIN-ALEXANDER-PULASKI-MASSAC-GIBSON-PIKE-POSEY-VANDERBURGH-
WARRICK-SPENCER-FULTON-HICKMAN-CARLISLE-BALLARD-MCCRACKEN-GRAVES-
LIVINGSTON-MARSHALL-CALLOWAY-CRITTENDEN-LYON-TRIGG-CALDWELL-
UNION KY-WEBSTER-HOPKINS-CHRISTIAN-HENDERSON-DAVIESS-MCLEAN-
MUHLENBERG-TODD-PERRY MO-BOLLINGER-CAPE GIRARDEAU-WAYNE MO-CARTER-
RIPLEY-BUTLER-STODDARD-SCOTT-MISSISSIPPI-NEW MADRID-
339 AM CDT SUN APR 17 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN
ILLINOIS...SOUTHWEST INDIANA...WESTERN KENTUCKY AND SOUTHEAST
MISSOURI.

.DAY ONE...TODAY AND TONIGHT

FLOODING IS OCCURRING ON MANY AREA RIVERS. PLEASE REFER TO THE
FLOOD WARNINGS FOR ADDITIONAL INFORMATION.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THUNDERSTORMS ARE POSSIBLE OVER ALL OR PART OF THE QUAD STATE
REGION MONDAY AND MONDAY NIGHT. WIDESPREAD SEVERE WEATHER IS NOT
ANTICIPATED...BUT A FEW STORMS MAY REACH SEVERE LEVELS WITH
DAMAGING WINDS AND LARGE HAIL BEING THE PRIMARY THREATS.

THE POTENTIAL EXISTS FOR A SEVERE WEATHER OUTBREAK FROM TUESDAY
EVENING INTO EARLY WEDNESDAY AS A COLD FRONT SWEEPS EAST THROUGH
THE REGION. LARGE HAIL...DAMAGING WINDS...AND ISOLATED TORNADOES
ARE A POSSIBILITY...ALONG WITH LOCALLY HEAVY RAINS.

YET ANOTHER CHANCE FOR STRONG TO SEVERE THUNDERSTORMS WILL BE
POSSIBLE IN THE THURSDAY NIGHT THROUGH FRIDAY NIGHT TIME FRAME.
RIGHT NOW...THE HIGHEST CHANCE FOR SEVERE STORMS LOOKS TO BE LATE
FRIDAY OR FRIDAY NIGHT AS A ANOTHER COLD FRONT CROSSES THE REGION.

FLOODING IS EXPECTED TO CONTINUE ON MANY AREA RIVERS. PLEASE
REFER TO THE FLOOD WARNINGS FOR ADDITIONAL INFORMATION.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS A GOOD BET TUESDAY EVENING INTO EARLY
WEDNESDAY. ON AND OFF ACTIVATION MAY ALSO BE REQUIRED IN THE
THURSDAY NIGHT THROUGH FRIDAY NIGHT TIME FRAME.

$$

JP

SPC AC 180559

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1259 AM CDT MON APR 18 2011

VALID 191200Z - 201200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF
AR/MO/IL/INDIANA/KY AND FAR WESTERN TN...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SOUTHERN PLAINS TO THE
MIDWEST/OH RIVER VALLEY...

...MIDWEST/OZARKS AND OH/MIDDLE MS RIVER VALLEYS...

A VERY ACTIVE SEVERE WEATHER DAY IS EXPECTED ACROSS THE REGION ON
TUESDAY/TUESDAY NIGHT...INCLUDING THE POSSIBILITY OF SOME STRONG
TORNADOES IN ADDITION TO LARGE HAIL AND WIDESPREAD DAMAGING WINDS
TUESDAY AFTERNOON/NIGHT.

INITIALLY...EARLY DAY ELEVATED TSTMS /SOME CAPABLE OF SEVERE HAIL/
WILL BE ONGOING ACROSS THE MIDWEST/OH RIVER VALLEY...ON THE NOSE OF
A STRONG SOUTHWESTERLY LOW LEVEL JET AND ON THE EDGE OF A
NORTHEASTWARD BUILDING ELEVATED MIXED LAYER /EML/. SUCH A HAIL
THREAT COULD INCLUDE DOWNSTATE PORTIONS OF IL/INDIANA INTO
KY/SOUTHERN OH THROUGH THE MORNING.

OTHERWISE...BENEATH AN EML-DRIVEN CAP...LOW LEVEL MOISTURE WILL
CONTINUE TO AGGRESSIVELY RETURN NORTH-NORTHEASTWARD AS STRONG
SOUTHWESTERLY LOW LEVEL WINDS ARE MAINTAINED THROUGH THE DAY. WITH
RELATIVELY RICH MOISTURE /AROUND 70 F SURFACE DEWPOINTS AND
REFERENCE THE 00Z OBSERVED CORPUS CHRISTI RAOB/ ALREADY RETURNING
INLAND ACROSS SOUTHEAST TX EARLY TODAY...IT IS PLAUSIBLE THAT A
BROAD CORRIDOR OF LOWER TO MIDDLE 60S F SURFACE DEWPOINTS WILL
BECOME INCREASINGLY ESTABLISHED TO THE EAST OF A LOWER MO VALLEY
SURFACE LOW AND ALONG/SOUTH OF A NORTHWARD MOVING WARM FRONT ACROSS
THE OH RIVER VALLEY/MIDWEST. BENEATH THE STRONG EML/PLUME OF STEEP
MID LEVEL LAPSE RATES...MODERATELY TO STRONG INSTABILITY WILL LIKELY
EXIST ACROSS THE PRE-COLD FRONTAL WARM SECTOR BY AFTERNOON...WITH
UPWARDS OF 2000-4000 J/KG OF MLCAPE POSSIBLE WITHIN A CORRIDOR FROM
EASTERN OK AND AR INTO THE SOUTHEAST HALF OF MO/DOWNSTATE IL AND
ADJACENT PORTIONS OF THE MIDDLE MS VALLEY.

A SOUTH-CENTRAL ROCKIES/CENTRAL PLAINS SHORTWAVE TROUGH EARLY
TUESDAY IS EXPECTED TO GRADUALLY AMPLIFY AND ADVANCE
NORTHEASTWARD/TAKE ON A MORE NEGATIVE TILT ESPECIALLY TUESDAY NIGHT
TOWARD THE UPPER MS RIVER VALLEY/UPPER GREAT LAKES REGION. ATTENDANT
LARGE SCALE FORCING FOR ASCENT/HEIGHT FALLS AND THE ASSOCIATED COLD
FRONT SHOULD ERODE AN OTHERWISE STRONG CAP...WITH SURFACE BASED
TSTMS LIKELY TO ERUPT BY MID/LATE AFTERNOON INTO EARLY EVENING AHEAD
OF THE DEEPENING LOWER MO VALLEY/MIDDLE MS VALLEY SURFACE LOW AND
NORTHEAST-SOUTHWEST ORIENTED COLD FRONT. SUCH VIGOROUS DEEP
CONVECTIVE DEVELOPMENT CURRENTLY APPEARS MOST LIKELY TO INITIALLY
OCCUR ACROSS CENTRAL/SOUTHWEST MO AS WELL AS WESTERN IL AND
NORTHWEST AR/NORTHEAST OK.

AMPLE LOW LEVEL MOISTURE/VERY STEEP LAPSE RATES AND DEEP LAYER
SHEAR OF 40-50 KT COINCIDENT WITH THE COLD FRONT/ADJACENT WARM
SECTOR WILL BE FURTHER ACCENTUATED BY LONG/CURVING LOW LEVEL
HODOGRAPHS AIDED BY 40-55 KT WINDS WITHIN THE LOWEST 1-2 KM. WHILE
VERY LARGE HAIL AND TORNADOES /PERHAPS A FEW STRONG/ WILL BE
POSSIBLE WITH INITIAL SUPERCELLULAR DEVELOPMENT...SEVERAL FACTORS
IMPLY A QUASI-LINEAR EVOLUTION IS PROBABLE SEVERAL HOURS AFTER DEEP
CONVECTIVE INITIATION /ESPECIALLY MID EVENING AND BEYOND/ ACROSS THE
MIDWEST/OH VALLEY. THIS INCLUDES THE LIKELIHOOD/DOMINANCE OF COLD
FRONTAL-TYPE INITIATION /GIVEN A STOUT EML OTHERWISE ACROSS THE WARM
SECTOR/...AS WELL AS RELATIVELY MODEST HIGH LEVEL FLOW/SHEAR AS
COMPARED TO THE LOWER-MIDDLE TROPOSPHERE. UPSCALE GROWTH INTO AN
INCREASINGLY WELL-ORGANIZED/ACCELERATING SQUALL LINE...INCLUDING
LEWP/BOW EVOLUTIONS....IS PROBABLE TUESDAY NIGHT ACROSS THE OH
VALLEY. AS SUCH...A WIDESPREAD DAMAGING WIND AND ISOLATED TORNADO
THREAT SHOULD EVOLVE BY MID/LATE EVENING...AND CONTINUE INTO THE
OVERNIGHT. A RELATIVELY BROAD WARM/MOIST SECTOR ASIDE...THIS WILL BE
SUPPORTED ON THE LARGE SCALE BY THE ANTICIPATED DEEPENING PHASE OF
THE SURFACE CYCLONE TOWARD THE UPPER GREAT LAKES AND A
REINVIGORATION OF A NOCTURNALLY ENHANCED LOW LEVEL WIND FIELD /50-60
KT SOUTHWESTERLY WINDS AROUND 1-2 KM/.

...SOUTHERN PLAINS/ARKLATEX...
PARTIALLY ATTRIBUTABLE TO MORE MODEST LARGE SCALE FORCING FOR ASCENT
AT THESE LATITUDES...A RELATIVELY MORE ISOLATED SEVERE THREAT WILL
BE POSSIBLE IN VICINITY OF THE NORTH-SOUTH DRYLINE ACROSS EASTERN
OK/NORTHEAST TX INTO WESTERN AR/FAR NORTHWEST LA. SUPERCELLS CAPABLE
OF LARGE HAIL AND PERHAPS A TORNADO WILL BE POSSIBLE TUESDAY LATE
AFTERNOON/EVENING. THE COLD FRONT WILL GRADUALLY OVERTAKE THE
DRYLINE FROM NORTHWEST TO SOUTHEAST ACROSS EASTERN OK INTO AR AND
EVENTUALLY NORTH TX/FAR NORTHWEST LA TUESDAY NIGHT. FARTHER
WEST...OTHER MORE ISOLATED/MARGINAL SEVERE TSTMS WITH A HAIL/WIND
RISK COULD DEVELOP ALONG THE WESTWARD EXTENSION OF THE
SOUTH-SOUTHEASTWARD MOVING COLD FRONT ACROSS OK AND THE TX PANHANDLE
TUESDAY LATE AFTERNOON/EARLY EVENING.

..GUYER.. 04/18/2011

CLICK TO GET WUUS02 PTSDY2 PRODUCT

TFGQ wrote:anyone know what the dewpoint forecast is gonna be for lower michigan

GRAYSONCO.WX wrote:What's it looking like for southern Oklahoma? Big storms possible tomorrow?

GCANE wrote:

GRAYSONCO.WX wrote:What's it looking like for southern Oklahoma? Big storms possible tomorrow?

Maybe a moderate threat of tornadoes early afternoon in the SE corner of OK.

WeatherGuesser wrote:Any thoughts on SPC going High?

WeatherGuesser wrote:Any thoughts on SPC going High?