Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 220659
SWODY2
SPC AC 220658

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CST SAT NOV 22 2014

VALID 231200Z - 241200Z

...THERE IS AN ENH RISK OF SVR TSTMS FOR PORTIONS OF THE CENTRAL
GULF COAST STATES...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE LOWER MS
VALLEY EWD TO NRN FL AND THE CAROLINAS...

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF ERN AR INTO THE
LOWER OH VALLEY...

...SUMMARY...
STRONG TO SEVERE THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE FROM THE
LOWER MISSISSIPPI VALLEY EASTWARD ACROSS THE GULF COAST STATES AND
NORTHEASTWARD INTO THE EASTERN CAROLINAS ON SUNDAY.  DAMAGING WIND
GUSTS AND THE POSSIBILITY FOR A COUPLE OF TORNADOES ARE FORECAST TO
BE THE PRIMARY THREATS.

...SYNOPSIS...
A VIGOROUS LOWER-LATITUDE SHORTWAVE TROUGH OVER THE NWRN GULF COAST
SUNDAY MORNING WILL RAPIDLY MOVE TO THE LOWER OH VALLEY BY EVENING.
CONCURRENTLY...AN INTENSIFYING MID-LEVEL SPEED MAX WILL STRENGTHEN
TO 100 KT AS IT ROUNDS THE BASE OF A LARGER-SCALE TROUGH AND MOVES
FROM THE SRN ROCKIES THROUGH THE LOWER MS VALLEY AND INTO KY/TN BY
DAYBREAK MONDAY.

IN THE LOW-LEVELS...A SURFACE LOW IS FORECAST TO DEVELOP/DEEPEN FROM
OK TO THE MID MS RIVER VALLEY BY SUNDAY EVENING AND CNTRL GREAT
LAKES EARLY MONDAY.  A WARM FRONT IS FORECAST TO ADVANCE NWD ACROSS
THE LOWER MS AND TN RIVER VALLEYS DURING THE DAY AS A COLD FRONT
MOVES EWD ACROSS THE MS VALLEY.

...LOWER MS VALLEY EWD INTO AL/GA/FL...
SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS IN A CONVECTIVE LINE
WILL LIKELY BE ONGOING AT DAYBREAK SUNDAY OVER THE LOWER MS VALLEY
AND NWRN GULF OF MEXICO.  THE NWD ADVANCING WARM FRONT FOLLOWED BY
MIDDLE 60S DEWPOINTS INTO CNTRL MS AND AL WILL LEAD TO MARGINAL
BUOYANCY /250-1000 J PER KG MLCAPE/ IMMEDIATELY DOWNSTREAM OF THE
SQUALL LINE.  STRONG MID-LEVEL HEIGHT FALLS COMBINED WITH A
STRENGTHENING LLJ /50 KT/ AND STRONG DEEP-LAYER SHEAR WILL SUPPORT
THE POSSIBILITY FOR A STRONGLY FORCED LINE MOVING ACROSS THE LOWER
MS VALLEY INTO PORTIONS OF AL.  AN ENHANCED RISK FOR DMGG WIND AND
AN ISOLD TORNADO MAY ACCOMPANY ANY LONGER-LIVED EMBEDDED
MESOVORTICES/SUPERCELLS AND BOWING SEGMENTS AS THE LINE MOVES EWD
ALONG THE CNTRL GULF COAST STATES.

DURING THE MORNING AND FARTHER E...A NWD ADVANCING WARM FRONT OVER
THE NERN GULF STATES WILL AID IN FOCUSING LIFT AS 60S DEG F BOUNDARY
LAYER DEWPOINTS MOVE NWD INTO CNTRL PORTIONS OF GA/AL.  ALTHOUGH
MUCH OF THIS ACTIVITY MAY BE ELEVATED NEAR THE FRONT...AN ISOLD
STRONG TO SEVERE STORM THREAT MAY ACCOMPANY A FEW OF THESE STORMS IF
PARCELS CAN ROOT NEAR THE SURFACE.

...ERN CAROLINAS SUNDAY NIGHT...
THE SYNOPTIC WARM FRONT IS FORECAST TO MOVE NWD THROUGH THE
CAROLINAS DURING THE PERIOD AND SERVE TO CONCENTRATE
SHOWERS/THUNDERSTORMS OVER THE CAROLINAS.  A STRONG POLEWARD
MOISTURE FLUX WILL PROBABLY LEAD TO APPRECIABLE MOISTURE
INFILTRATING THE COASTAL PLAIN AND PIEDMONT DOWNSTREAM OF THE
INTENSE MID-LEVEL JET MOVING INTO KY/TN DURING THE OVERNIGHT.
DESPITE MODEST MID-LEVEL LAPSE RATES...THE COMBINATION OF INCREASING
BUOYANCY AND STRENGTHENING SHEAR PROFILES WILL SUPPORT PERHAPS AN
INCREASING RISK FOR DMGG WINDS AND A FEW TORNADOES.

...LOWER TN/OH VALLEYS...
CONSIDERABLE UNCERTAINTY REMAINS REGARDING THE DEGREE OF
DESTABILIZATION THAT CAN OCCUR FROM NERN AR NEWD INTO THE LOWER OH
VALLEY WITH EXPECTED WIDESPREAD SHOWERS/THUNDERSTORMS FORECAST
FARTHER S.  NONETHELESS...THE PRIMARY SURFACE CYCLONE IS PROGGED TO
REACH THE MID MS VALLEY BY LATE AFTERNOON.  A WARM FRONT WILL LIFT
NWD THROUGH THIS AREA FOLLOWED BY RELATIVELY MOIST UPPER 50S
DEWPOINTS.  YET...COOLER MID-LEVEL TEMPS IN CLOSER PROXIMITY TO THE
LARGER-SCALE TROUGH AND DOWNSTREAM OF THE AFOREMENTIONED MID-LEVEL
JET MAY RESULT IN A FEW STRONGER STORMS PRIMARILY CAPABLE OF AN
ISOLD DMGG WIND THREAT.

..SMITH.. 11/22/2014




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