Moderate Risk- Northern GA into Western & Central Caroli
Posted: Fri Apr 01, 2005 1:13 am
SPC AC 010549
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1149 PM CST THU MAR 31 2005
VALID 011200Z - 021200Z
THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 SW
TYS 30 W HKY 40 WNW GSO 45 NNW RWI 25 SE RWI 35 WNW ILM 55 SSW AGS
40 ENE ANB 15 W CHA 40 SW TYS.
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 SSW
LCH HEZ UOX 30 WNW CSV 35 NW TRI 45 NNW SSU 45 SW DCA 35 NE ORF
...CONT... 10 ENE PBI 55 ESE FMY 15 SW FMY.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SSW LCH 10 NNE HEZ
40 N GLH 15 N HOT 30 SSW HRO 15 WSW MDH 45 ESE IND 30 WNW CMH 15 SSE
JHW 35 ESE BGM 20 SE NEL.
...THERE IS A MDT RISK OF SVR TSTMS THIS AFTN AND EVE IN THE LEE OF
THE SRN APPALACHIANS...FROM PARTS OF NRN GA INTO THE WRN AND CENTRAL
CAROLINAS....
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
AREA ACROSS MUCH OF THE REMAINDER OF THE SOUTHEAST STATES....
A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG ACROSS THE SOUTHERN
PLAINS TOWARD THE LOWER MISSISSIPI VALLEY. MEANWHILE...IN BELT OF
STRONGER FLOW TO THE NORTH....ANOTHER SHORT WAVE TROUGH IS READILY
EVIDENT IN SATELLITE IMAGERY DIGGING ACROSS THE NORTHERN PLAINS INTO
THE UPPER MISSISSIPPI VALLEY. MODELS ARE SIMILAR IN SUGGESTING THAT
BOTH THESE FEATURES WILL COME IN PHASE LATER
TODAY/TONIGHT...EVOLVING INTO A LARGE NEUTRAL TO NEGATIVELY TILTED
UPPER TROUGH EAST OF THE MISSISSIPPI RIVER BY 12Z SATURDAY.
WEAK SURFACE WAVE DEVELOPMENT ALREADY APPEARS UNDERWAY ACROSS THE
LOWER MISSISSIPPI VALLEY IN ASSOCIATION WITH SOUTHERN BRANCH TROUGH.
EVOLVING UPPER FLOW PATTERN APPEARS LIKELY TO SUPPORT MORE RAPIDLY
DEEPENING SURFACE CYCLONE ACROSS THE UPPER TENNESSEE VALLEY BY THIS
AFTERNOON...BEFORE CYCLOGENESIS PROCESS CONTINUES UP THE WESTERN
SLOPES OF THE SOUTHERN APPALACHIANS INTO THE CENTRAL APPALACHIANS BY
EARLY SATURDAY MORNING.
MEAN FLOW FIELDS/SHEAR PROFILES WILL STRENGTHEN IN WARM SECTOR OF
EVOLVING CYCLONE ACROSS MUCH OF THE SOUTHEAST. PRIMARY UNCERTAINTY
WITH REGARD TO EXTENT/INTENSITY OF OVERALL SEVERE THREAT CONCERNS
MAGNITUDE OF DESTABILIZATION IN WARM SECTOR. SURFACE HEATING IN THE
LEE OF THE SOUTHERN APPALACHIANS MAY BE LIMITED DUE TO EXTENSIVE
WARM ADVECTION CONVECTION EARLY IN THE PERIOD. FURTHERMORE...WITH
SOUTHERN STREAM TROUGH REMAINING POSITIVELY TILTED THROUGH MUCH OF
THE DAYTIME HOURS...MID-LEVEL LAPSE RATES WILL NOT BECOME
PARTICULARLY STEEP. HOWEVER...A MOIST...CONDITIONALLY UNSTABLE
ENVIRONMENT IS ALREADY IN PLACE ACROSS THE EASTERN GULF/SOUTH
ATLANTIC COAST STATES...AND...GIVEN STRONG FORCING FOR UPWARD
VERTICAL MOTION PROGGED TO SWEEP ACROSS THE SOUTHEAST...SEVERE
THREAT APPEARS ELEVATED.
...CENTRAL GULF STATES...
SEVERE THREAT ASSOCIATED WITH DEVELOPING SURFACE LOW MAY BE ONGOING
ACROSS PARTS OF MISSISSIPPI/ALABAMA EARLY IN THE PERIOD. FOCUS FOR
MOST EXTENSIVE CONVECTIVE DEVELOPMENT IS EXPECTED TO BE WARM FRONT
EAST OF SURFACE LOW...ACROSS NORTH CENTRAL MISSISSIPPI/ALABAMA...BUT
PRE-FRONTAL SURFACE WIND SHIFT MAY FOCUS SCATTERED ACTIVITY FROM
SURFACE LOW SOUTHWARD INTO THE GULF COAST.
MODELS SUGGEST STRONGER LOW-LEVEL WARM ADVECTION REGIME WILL RAPIDLY
DEVELOP NORTH/EAST OF THE CENTRAL GULF COAST STATES BY THE AFTERNOON
HOURS...BUT MID-LEVEL FORCING AHEAD OF UPPER TROUGH AXIS MAY
MAINTAIN INTENSE CONVECTION ALONG PRE-FRONTAL WIND SHIFT. SHEAR
PROFILES WILL BECOME INCREASINGLY UNIDIRECTIONAL...BUT WILL REMAIN
SUFFICIENT FOR SEVERE STORMS IN ENVIRONMENT WITH MEAN MIXED CAPE IN
EXCESS OF 1000 J/KG. LARGE HAIL/DAMAGING WIND GUSTS WILL BE PRIMARY
THREATS...BUT ISOLATED TORNADOES WILL ALSO BE POSSIBLE.
...EASTERN GULF/SOUTH ATLANTIC COAST STATES...
MORE SUBSTANTIAL TORNADO POTENTIAL MAY EVOLVE IN THE LEE OF THE
SOUTHERN APPALACHIANS...FROM NORTHERN GEORGIA INTO THE WESTERN/
CENTRAL CAROLINAS. THIS SHOULD OCCUR AS MORE EXTENSIVE WARM
ADVECTION PRECIPITATION SHIELD SHIFTS INTO THE MID ATLANTIC STATES
DURING THE LATE AFTERNOON/EVENING HOURS. WHILE SURFACE HEATING WILL
BE LIMITED...INHIBITION IN SOUTHEASTERLY MOIST UPSLOPE FLOW IS
EXPECTED TO BE WEAK ENOUGH FOR CONVECTIVE DEVELOPMENT EAST/SOUTHEAST
OF SURFACE LOW TRACK.
MODELS SUGGEST SURFACE CYCLONE WILL DEEPEN BELOW 1000 MB LATE THIS
AFTERNOON AND EVENING AS CENTER TRACKS FROM NORTHEAST ALABAMA
THROUGH EXTREME EASTERN TENNESSEE. BACKED SURFACE FLOW ALONG THE
LEE SLOPES OF THE SOUTHERN APPALACHIANS BENEATH STRENGTHENING
SOUTHWESTERLY MID-LEVEL FLOW WILL PROVIDE FAVORABLE HODOGRAPHS FOR
SUPERCELLS WITH TORNADOES. ACTIVITY WILL BE AIDED BY STRONGLY
DIFLUENT/DIVERGENT UPPER FLOW...WHICH WILL SHIFT EAST NORTHEASTWARD
TOWARD THE SOUTHERN MID ATLANTIC COAST TONIGHT.
STRONG CONVERGENCE ALONG SEA BREEZE ACROSS INTERIOR NORTHEAST
FLORIDA/SOUTHEAST GEORGIA COULD PROVIDE ANOTHER FOCUS FOR SUPERCELL
DEVELOPMENT DURING THE AFTERNOON HOURS. OTHERWISE... UNCERTAINTY
EXISTS ABOUT WHETHER A SQUALL LINE WILL CONTINUE AHEAD OF COLD
FRONT ADVANCING FROM THE EASTERN GULF STATES INTO THE SOUTH ATLANTIC
COAST STATES TONIGHT. HOWEVER...POTENTIAL FOR EVOLVING LINE COULD
INCREASE ACROSS THE EASTERN CAROLINAS...AS APPROACHING UPPER TROUGH
TAKES ON AN INCREASINGLY NEUTRAL TILT.
..KERR/JEWELL.. 04/01/2005
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1149 PM CST THU MAR 31 2005
VALID 011200Z - 021200Z
THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 SW
TYS 30 W HKY 40 WNW GSO 45 NNW RWI 25 SE RWI 35 WNW ILM 55 SSW AGS
40 ENE ANB 15 W CHA 40 SW TYS.
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 SSW
LCH HEZ UOX 30 WNW CSV 35 NW TRI 45 NNW SSU 45 SW DCA 35 NE ORF
...CONT... 10 ENE PBI 55 ESE FMY 15 SW FMY.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 SSW LCH 10 NNE HEZ
40 N GLH 15 N HOT 30 SSW HRO 15 WSW MDH 45 ESE IND 30 WNW CMH 15 SSE
JHW 35 ESE BGM 20 SE NEL.
...THERE IS A MDT RISK OF SVR TSTMS THIS AFTN AND EVE IN THE LEE OF
THE SRN APPALACHIANS...FROM PARTS OF NRN GA INTO THE WRN AND CENTRAL
CAROLINAS....
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
AREA ACROSS MUCH OF THE REMAINDER OF THE SOUTHEAST STATES....
A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG ACROSS THE SOUTHERN
PLAINS TOWARD THE LOWER MISSISSIPI VALLEY. MEANWHILE...IN BELT OF
STRONGER FLOW TO THE NORTH....ANOTHER SHORT WAVE TROUGH IS READILY
EVIDENT IN SATELLITE IMAGERY DIGGING ACROSS THE NORTHERN PLAINS INTO
THE UPPER MISSISSIPPI VALLEY. MODELS ARE SIMILAR IN SUGGESTING THAT
BOTH THESE FEATURES WILL COME IN PHASE LATER
TODAY/TONIGHT...EVOLVING INTO A LARGE NEUTRAL TO NEGATIVELY TILTED
UPPER TROUGH EAST OF THE MISSISSIPPI RIVER BY 12Z SATURDAY.
WEAK SURFACE WAVE DEVELOPMENT ALREADY APPEARS UNDERWAY ACROSS THE
LOWER MISSISSIPPI VALLEY IN ASSOCIATION WITH SOUTHERN BRANCH TROUGH.
EVOLVING UPPER FLOW PATTERN APPEARS LIKELY TO SUPPORT MORE RAPIDLY
DEEPENING SURFACE CYCLONE ACROSS THE UPPER TENNESSEE VALLEY BY THIS
AFTERNOON...BEFORE CYCLOGENESIS PROCESS CONTINUES UP THE WESTERN
SLOPES OF THE SOUTHERN APPALACHIANS INTO THE CENTRAL APPALACHIANS BY
EARLY SATURDAY MORNING.
MEAN FLOW FIELDS/SHEAR PROFILES WILL STRENGTHEN IN WARM SECTOR OF
EVOLVING CYCLONE ACROSS MUCH OF THE SOUTHEAST. PRIMARY UNCERTAINTY
WITH REGARD TO EXTENT/INTENSITY OF OVERALL SEVERE THREAT CONCERNS
MAGNITUDE OF DESTABILIZATION IN WARM SECTOR. SURFACE HEATING IN THE
LEE OF THE SOUTHERN APPALACHIANS MAY BE LIMITED DUE TO EXTENSIVE
WARM ADVECTION CONVECTION EARLY IN THE PERIOD. FURTHERMORE...WITH
SOUTHERN STREAM TROUGH REMAINING POSITIVELY TILTED THROUGH MUCH OF
THE DAYTIME HOURS...MID-LEVEL LAPSE RATES WILL NOT BECOME
PARTICULARLY STEEP. HOWEVER...A MOIST...CONDITIONALLY UNSTABLE
ENVIRONMENT IS ALREADY IN PLACE ACROSS THE EASTERN GULF/SOUTH
ATLANTIC COAST STATES...AND...GIVEN STRONG FORCING FOR UPWARD
VERTICAL MOTION PROGGED TO SWEEP ACROSS THE SOUTHEAST...SEVERE
THREAT APPEARS ELEVATED.
...CENTRAL GULF STATES...
SEVERE THREAT ASSOCIATED WITH DEVELOPING SURFACE LOW MAY BE ONGOING
ACROSS PARTS OF MISSISSIPPI/ALABAMA EARLY IN THE PERIOD. FOCUS FOR
MOST EXTENSIVE CONVECTIVE DEVELOPMENT IS EXPECTED TO BE WARM FRONT
EAST OF SURFACE LOW...ACROSS NORTH CENTRAL MISSISSIPPI/ALABAMA...BUT
PRE-FRONTAL SURFACE WIND SHIFT MAY FOCUS SCATTERED ACTIVITY FROM
SURFACE LOW SOUTHWARD INTO THE GULF COAST.
MODELS SUGGEST STRONGER LOW-LEVEL WARM ADVECTION REGIME WILL RAPIDLY
DEVELOP NORTH/EAST OF THE CENTRAL GULF COAST STATES BY THE AFTERNOON
HOURS...BUT MID-LEVEL FORCING AHEAD OF UPPER TROUGH AXIS MAY
MAINTAIN INTENSE CONVECTION ALONG PRE-FRONTAL WIND SHIFT. SHEAR
PROFILES WILL BECOME INCREASINGLY UNIDIRECTIONAL...BUT WILL REMAIN
SUFFICIENT FOR SEVERE STORMS IN ENVIRONMENT WITH MEAN MIXED CAPE IN
EXCESS OF 1000 J/KG. LARGE HAIL/DAMAGING WIND GUSTS WILL BE PRIMARY
THREATS...BUT ISOLATED TORNADOES WILL ALSO BE POSSIBLE.
...EASTERN GULF/SOUTH ATLANTIC COAST STATES...
MORE SUBSTANTIAL TORNADO POTENTIAL MAY EVOLVE IN THE LEE OF THE
SOUTHERN APPALACHIANS...FROM NORTHERN GEORGIA INTO THE WESTERN/
CENTRAL CAROLINAS. THIS SHOULD OCCUR AS MORE EXTENSIVE WARM
ADVECTION PRECIPITATION SHIELD SHIFTS INTO THE MID ATLANTIC STATES
DURING THE LATE AFTERNOON/EVENING HOURS. WHILE SURFACE HEATING WILL
BE LIMITED...INHIBITION IN SOUTHEASTERLY MOIST UPSLOPE FLOW IS
EXPECTED TO BE WEAK ENOUGH FOR CONVECTIVE DEVELOPMENT EAST/SOUTHEAST
OF SURFACE LOW TRACK.
MODELS SUGGEST SURFACE CYCLONE WILL DEEPEN BELOW 1000 MB LATE THIS
AFTERNOON AND EVENING AS CENTER TRACKS FROM NORTHEAST ALABAMA
THROUGH EXTREME EASTERN TENNESSEE. BACKED SURFACE FLOW ALONG THE
LEE SLOPES OF THE SOUTHERN APPALACHIANS BENEATH STRENGTHENING
SOUTHWESTERLY MID-LEVEL FLOW WILL PROVIDE FAVORABLE HODOGRAPHS FOR
SUPERCELLS WITH TORNADOES. ACTIVITY WILL BE AIDED BY STRONGLY
DIFLUENT/DIVERGENT UPPER FLOW...WHICH WILL SHIFT EAST NORTHEASTWARD
TOWARD THE SOUTHERN MID ATLANTIC COAST TONIGHT.
STRONG CONVERGENCE ALONG SEA BREEZE ACROSS INTERIOR NORTHEAST
FLORIDA/SOUTHEAST GEORGIA COULD PROVIDE ANOTHER FOCUS FOR SUPERCELL
DEVELOPMENT DURING THE AFTERNOON HOURS. OTHERWISE... UNCERTAINTY
EXISTS ABOUT WHETHER A SQUALL LINE WILL CONTINUE AHEAD OF COLD
FRONT ADVANCING FROM THE EASTERN GULF STATES INTO THE SOUTH ATLANTIC
COAST STATES TONIGHT. HOWEVER...POTENTIAL FOR EVOLVING LINE COULD
INCREASE ACROSS THE EASTERN CAROLINAS...AS APPROACHING UPPER TROUGH
TAKES ON AN INCREASINGLY NEUTRAL TILT.
..KERR/JEWELL.. 04/01/2005