000
ACUS03 KWNS 240732
SWODY3
SPC AC 240730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT FRI MAY 24 2013
VALID 261200Z - 271200Z
...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF NERN WY / WRN SD /
WRN NEB...
...SYNOPSIS...
THE UPPER PATTERN FOR THE DAY 3 PERIOD IS CHARACTERIZED BY A WRN
U.S. UPPER TROUGH CENTERED OVER THE PACIFIC NW...A MID LEVEL RIDGE
OVER THE CNTRL U.S...AND A SLOW-TO-DEPART CLOSED LOW OVER NEW
ENGLAND. MODELS HINT AT A LEAD DISTURBANCE MOVING INTO THE CNTRL
HIGH PLAINS BY SUNDAY EVENING AS A WEAK CNTRL HIGH PLAINS LOW
BECOMES ESTABLISHED WITH AN ATTENDANT LEE SURFACE TROUGH/DRYLINE.
...CNTRL AND NRN PLAINS...
EARLY DAY STORMS --PERHAPS ONGOING AT THE START OF THE PERIOD-- MAY
OCCUR INVOF A RESIDUAL NW-SE ORIENTED FRONTAL ZONE OVER THE MID MO
VALLEY REGION. FORECAST SOUNDINGS SHOW ONLY MARGINAL INSTABILITY
AND MODEST DEEP FLOW AND WOULD SUGGEST THESE STORMS MAY BE
SUB-SEVERE. ATTENTION FOCUSES WWD OVER THE NRN-CNTRL HIGH PLAINS
LATER IN THE DAY AS STRONG HEATING IS FORECAST TO OCCUR ON THE WRN
EDGE OF MOISTURE LOCATED OVER THE CNTRL-NRN HIGH PLAINS. A STOUT
EML FEATURING 12-14 DEG C H7 TEMPS FROM THE TX PANHANDLE NWD THROUGH
WRN KS WILL LIKELY LIMIT STORM COVERAGE FROM WRN KS SWD INTO WRN TX
ON THE DRYLINE. WEAK HEIGHT FALLS BY EVENING OVER THE CNTRL HIGH
PLAINS IN ASSOCIATION WITH AN EJECTING IMPULSE AND GENERALLY
LOWERING HEIGHTS OVER THE NRN PLAINS IN ADVANCE OF A NRN GREAT BASIN
SPEED MAXIMA...WOULD IN TURN BECOME MORE FAVORABLE FOR STORM
DEVELOPMENT.
FORECAST SOUNDINGS FROM PARTS OF WRN KS TOWARDS THE BLACK HILLS SHOW
A VERY STEEP LAPSE RATE ENVIRONMENT WITH SBCAPE RANGING FROM
1500-2500 J/KG EXPECTED NEAR AND E OF THE DRYLINE/LEE TROUGH. DEEP
LAYER SHEAR WILL LIKELY REMAIN MODEST /25-35 KT EFFECTIVE SHEAR/
OVER THE REGION. STRONG HEATING WILL ACT IN CONCERT TO WEAKEN AND
LOCALLY ERODE THE CAP WITH ISOLD STORM COVERAGE EXPECTED. THE LLJ
IS FORECAST TO STRENGTHEN DURING THE EVENING INTO THE
OVERNIGHT...POTENTIALLY ALLOWING SOME OF THE EVENING STORMS TO
LINGER INTO THE OVERNIGHT.
...WRN KS SWD INTO WRN TX...
A FEW DIURNALLY-DRIVEN STORMS MAY FORM BY THE LATE AFTERNOON/EARLY
EVENING HOURS WITHIN A DEEPLY MIXED BOUNDARY LAYER. SHEAR PROFILES
WILL SUPPORT SOME STORM ORGANIZATION IN THE FORM OF MULTICELLS AND
PERHAPS TRANSIENT SUPERCELL STRUCTURES. ISOLD DMGG WINDS AND LARGE
HAIL MAY OCCUR WITH THE STRONGEST STORMS.
..SMITH.. 05/24/2013
000
ACUS03 KWNS 240732
SWODY3
SPC AC 240730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT FRI MAY 24 2013
VALID 261200Z - 271200Z
...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF NERN WY / WRN SD /
WRN NEB...
...SYNOPSIS...
THE UPPER PATTERN FOR THE DAY 3 PERIOD IS CHARACTERIZED BY A WRN
U.S. UPPER TROUGH CENTERED OVER THE PACIFIC NW...A MID LEVEL RIDGE
OVER THE CNTRL U.S...AND A SLOW-TO-DEPART CLOSED LOW OVER NEW
ENGLAND. MODELS HINT AT A LEAD DISTURBANCE MOVING INTO THE CNTRL
HIGH PLAINS BY SUNDAY EVENING AS A WEAK CNTRL HIGH PLAINS LOW
BECOMES ESTABLISHED WITH AN ATTENDANT LEE SURFACE TROUGH/DRYLINE.
...CNTRL AND NRN PLAINS...
EARLY DAY STORMS --PERHAPS ONGOING AT THE START OF THE PERIOD-- MAY
OCCUR INVOF A RESIDUAL NW-SE ORIENTED FRONTAL ZONE OVER THE MID MO
VALLEY REGION. FORECAST SOUNDINGS SHOW ONLY MARGINAL INSTABILITY
AND MODEST DEEP FLOW AND WOULD SUGGEST THESE STORMS MAY BE
SUB-SEVERE. ATTENTION FOCUSES WWD OVER THE NRN-CNTRL HIGH PLAINS
LATER IN THE DAY AS STRONG HEATING IS FORECAST TO OCCUR ON THE WRN
EDGE OF MOISTURE LOCATED OVER THE CNTRL-NRN HIGH PLAINS. A STOUT
EML FEATURING 12-14 DEG C H7 TEMPS FROM THE TX PANHANDLE NWD THROUGH
WRN KS WILL LIKELY LIMIT STORM COVERAGE FROM WRN KS SWD INTO WRN TX
ON THE DRYLINE. WEAK HEIGHT FALLS BY EVENING OVER THE CNTRL HIGH
PLAINS IN ASSOCIATION WITH AN EJECTING IMPULSE AND GENERALLY
LOWERING HEIGHTS OVER THE NRN PLAINS IN ADVANCE OF A NRN GREAT BASIN
SPEED MAXIMA...WOULD IN TURN BECOME MORE FAVORABLE FOR STORM
DEVELOPMENT.
FORECAST SOUNDINGS FROM PARTS OF WRN KS TOWARDS THE BLACK HILLS SHOW
A VERY STEEP LAPSE RATE ENVIRONMENT WITH SBCAPE RANGING FROM
1500-2500 J/KG EXPECTED NEAR AND E OF THE DRYLINE/LEE TROUGH. DEEP
LAYER SHEAR WILL LIKELY REMAIN MODEST /25-35 KT EFFECTIVE SHEAR/
OVER THE REGION. STRONG HEATING WILL ACT IN CONCERT TO WEAKEN AND
LOCALLY ERODE THE CAP WITH ISOLD STORM COVERAGE EXPECTED. THE LLJ
IS FORECAST TO STRENGTHEN DURING THE EVENING INTO THE
OVERNIGHT...POTENTIALLY ALLOWING SOME OF THE EVENING STORMS TO
LINGER INTO THE OVERNIGHT.
...WRN KS SWD INTO WRN TX...
A FEW DIURNALLY-DRIVEN STORMS MAY FORM BY THE LATE AFTERNOON/EARLY
EVENING HOURS WITHIN A DEEPLY MIXED BOUNDARY LAYER. SHEAR PROFILES
WILL SUPPORT SOME STORM ORGANIZATION IN THE FORM OF MULTICELLS AND
PERHAPS TRANSIENT SUPERCELL STRUCTURES. ISOLD DMGG WINDS AND LARGE
HAIL MAY OCCUR WITH THE STRONGEST STORMS.
..SMITH.. 05/24/2013
000
ACUS01 KWNS 240600
SWODY1
SPC AC 240558
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT FRI MAY 24 2013
VALID 241200Z - 251200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN CO INTO WRN NEB AND
NWRN KS...
...SYNOPSIS...
SYNOPTIC UPPER PATTERN WILL REMAIN CHARACTERIZED BY OMEGA BLOCKING
REGIME WITH AN UPPER RIDGE OVER THE CNTRL U.S. FLANKED BY UPPER LOWS
OVER THE ERN AND WRN STATES. GRADUAL DEAMPLIFICATION OF THIS REGIME
WILL OCCUR AS SIGNIFICANT SHORTWAVE TROUGH EMBEDDED WITHIN WRN U.S.
UPPER LOW LIFTS NWD INTO SASKATCHEWAN...AND AS SHORTWAVE TROUGH
CURRENTLY OVER THE OH VALLEY EXITS THE ERN U.S. SEABOARD. COLD FRONT
WILL MOVE OFF THE ATLANTIC COAST EARLY IN THE PERIOD. THE TRAILING
PORTION OF THIS BOUNDARY WILL EXTEND WWD INTO THE SRN PLAINS EARLY
FRIDAY...BUT WILL DEVELOP NWD AS A WARM FRONT THROUGH THE CNTRL
PLAINS.
...CNTRL HIGH PLAINS...
RICHER LOW LEVEL MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO LOW 60S
WILL ADVECT NWD THROUGH THE CNTRL PLAINS ALONG A 50 KT SLY LLJ. THE
ATMOSPHERE WILL BECOME MODERATELY UNSTABLE OVER THE CNTRL HIGH
PLAINS WHERE THE STEEPER LAPSE RATES OVERLAP THE WRN EDGE OF THE
MOIST AXIS WITH 1500-2000 J/KG MLCAPE LIKELY FROM NERN CO INTO NWRN
KS AND WRN NEB. STORMS ARE EXPECTED TO DEVELOP INITIALLY OVER THE
HIGHER TERRAIN AND SPREAD NEWD THROUGH THE HIGH PLAINS. THIS REGION
WILL RESIDE JUST SE OF THE STRONGER FLOW ALOFT ASSOCIATED WITH THE
WRN U.S. UPPER LOW WITH GENERALLY 30-40 KT EFFECTIVE SHEAR
SUPPORTIVE OF A FEW SUPERCELLS. ISOLATED LARGE HAIL AND DAMAGING
WIND WILL BE THE MAIN THREATS...THROUGH A COUPLE TORNADOES WILL ALSO
BE POSSIBLE. ACTIVITY MAY EVOLVE INTO ONE OR MORE LINES/CLUSTERS
BEFORE WEAKENING DURING THE EVENING.
...SRN HIGH PLAINS...
OTHER STORMS WILL LIKELY DEVELOP OVER THE HIGHER TERRAIN AND THEN
INTENSIFY AS THEY MOVE EWD INTO THE INSTABILITY AXIS WHERE MODERATE
INSTABILITY IS EXPECTED. WEAK VERTICAL SHEAR WILL SUPPORT
MULTICELLS...BUT STEEP LAPSE RATES AND AN INVERTED-V LOW LEVEL
ENVIRONMENT WILL PROMOTE A THREAT OF ISOLATED HAIL AND STRONG WIND
GUSTS.
...SRN THROUGH SERN TX...
SWD PROPAGATING MCS MAY STILL BE ONGOING 12Z FRIDAY. THIS ACTIVITY
MAY POSE A MODEST RISK FOR ISOLATED STRONG WIND GUSTS AND HAIL. SOME
INTENSIFICATION MAY BE POSSIBLE ALONG RESIDUAL OUTFLOW BOUNDARIES AS
THE ATMOSPHERE DESTABILIZES. WEAK VERTICAL SHEAR SUGGESTS ACTIVITY
SHOULD REMAIN POORLY ORGANIZED...BUT RICH LOW LEVEL MOISTURE AND
MLCAPE FROM 2000-3000 J/KG MAY SUPPORT A THREAT OF ISOLATED DAMAGING
WING GUSTS AND HAIL.
..DIAL.. 05/24/2013
000
ACUS01 KWNS 240600
SWODY1
SPC AC 240558
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT FRI MAY 24 2013
VALID 241200Z - 251200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN CO INTO WRN NEB AND
NWRN KS...
...SYNOPSIS...
SYNOPTIC UPPER PATTERN WILL REMAIN CHARACTERIZED BY OMEGA BLOCKING
REGIME WITH AN UPPER RIDGE OVER THE CNTRL U.S. FLANKED BY UPPER LOWS
OVER THE ERN AND WRN STATES. GRADUAL DEAMPLIFICATION OF THIS REGIME
WILL OCCUR AS SIGNIFICANT SHORTWAVE TROUGH EMBEDDED WITHIN WRN U.S.
UPPER LOW LIFTS NWD INTO SASKATCHEWAN...AND AS SHORTWAVE TROUGH
CURRENTLY OVER THE OH VALLEY EXITS THE ERN U.S. SEABOARD. COLD FRONT
WILL MOVE OFF THE ATLANTIC COAST EARLY IN THE PERIOD. THE TRAILING
PORTION OF THIS BOUNDARY WILL EXTEND WWD INTO THE SRN PLAINS EARLY
FRIDAY...BUT WILL DEVELOP NWD AS A WARM FRONT THROUGH THE CNTRL
PLAINS.
...CNTRL HIGH PLAINS...
RICHER LOW LEVEL MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO LOW 60S
WILL ADVECT NWD THROUGH THE CNTRL PLAINS ALONG A 50 KT SLY LLJ. THE
ATMOSPHERE WILL BECOME MODERATELY UNSTABLE OVER THE CNTRL HIGH
PLAINS WHERE THE STEEPER LAPSE RATES OVERLAP THE WRN EDGE OF THE
MOIST AXIS WITH 1500-2000 J/KG MLCAPE LIKELY FROM NERN CO INTO NWRN
KS AND WRN NEB. STORMS ARE EXPECTED TO DEVELOP INITIALLY OVER THE
HIGHER TERRAIN AND SPREAD NEWD THROUGH THE HIGH PLAINS. THIS REGION
WILL RESIDE JUST SE OF THE STRONGER FLOW ALOFT ASSOCIATED WITH THE
WRN U.S. UPPER LOW WITH GENERALLY 30-40 KT EFFECTIVE SHEAR
SUPPORTIVE OF A FEW SUPERCELLS. ISOLATED LARGE HAIL AND DAMAGING
WIND WILL BE THE MAIN THREATS...THROUGH A COUPLE TORNADOES WILL ALSO
BE POSSIBLE. ACTIVITY MAY EVOLVE INTO ONE OR MORE LINES/CLUSTERS
BEFORE WEAKENING DURING THE EVENING.
...SRN HIGH PLAINS...
OTHER STORMS WILL LIKELY DEVELOP OVER THE HIGHER TERRAIN AND THEN
INTENSIFY AS THEY MOVE EWD INTO THE INSTABILITY AXIS WHERE MODERATE
INSTABILITY IS EXPECTED. WEAK VERTICAL SHEAR WILL SUPPORT
MULTICELLS...BUT STEEP LAPSE RATES AND AN INVERTED-V LOW LEVEL
ENVIRONMENT WILL PROMOTE A THREAT OF ISOLATED HAIL AND STRONG WIND
GUSTS.
...SRN THROUGH SERN TX...
SWD PROPAGATING MCS MAY STILL BE ONGOING 12Z FRIDAY. THIS ACTIVITY
MAY POSE A MODEST RISK FOR ISOLATED STRONG WIND GUSTS AND HAIL. SOME
INTENSIFICATION MAY BE POSSIBLE ALONG RESIDUAL OUTFLOW BOUNDARIES AS
THE ATMOSPHERE DESTABILIZES. WEAK VERTICAL SHEAR SUGGESTS ACTIVITY
SHOULD REMAIN POORLY ORGANIZED...BUT RICH LOW LEVEL MOISTURE AND
MLCAPE FROM 2000-3000 J/KG MAY SUPPORT A THREAT OF ISOLATED DAMAGING
WING GUSTS AND HAIL.
..DIAL.. 05/24/2013
000
ACUS02 KWNS 240553
SWODY2
SPC AC 240551
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CDT FRI MAY 24 2013
VALID 251200Z - 261200Z
...THERE IS A SLGT RISK OF SVR TSTMS FOR A PORTION OF ERN MT / FAR
NERN WY / WRN DAKOTAS...
...SYNOPSIS...
THE UPPER AIR PATTERN WILL FEATURE A WRN U.S. TROUGH/CNTRL U.S.
RIDGE/ERN U.S. TROUGH. DOWNSTREAM OF THE WRN STATES TROUGH...A
BROAD BELT OF MODERATE SWLY MID-LEVEL FLOW WILL OVERSPREAD THE NRN
HIGH PLAINS. A LEE SURFACE TROUGH OVER MUCH OF THE HIGH PLAINS WILL
SERVE AS A FOCUS FOR AFTERNOON/EVENING STORM DEVELOPMENT. FARTHER
E...A FRONTAL ZONE WILL EXTEND FROM THE ERN DAKOTAS TO THE MID MS
VALLEY TO THE WEST OF SURFACE HIGH PRESSURE CENTERED OVER THE GREAT
LAKES.
...NRN HIGH PLAINS INTO THE MID MO VALLEY...
NWD MOISTURE RETURN INTO THE CNTRL-NRN PLAINS ON THE BACKSIDE OF THE
MIDWEST SURFACE HIGH WILL BE ONGOING AT THE START OF THE DAY 2
PERIOD AS A CLOSED MID-LEVEL LOW REMAINS CENTERED OVER SRN BRITISH
COLUMBIA. THE LEE TROUGH LOCATED OVER CNTRL MT WILL ACT TO DRAW 50S
DEWPOINTS WESTWARD INTO ERN MT AND UPPER 50S DEWPOINTS INVOF THE
BLACK HILLS...CONTRIBUTING TO MARGINAL-MODERATE INSTABILITY. STRONG
DIURNAL HEATING WILL SEEMINGLY LEAD TO ISOLD TO WIDELY SCTD STORMS
IN THE LATE AFTERNOON-MID EVENING. DEEPLY VEERING WIND PROFILES
/40+ KT EFFECTIVE SHEAR/ WOULD SUPPORT STORM
ORGANIZATION...INCLUDING SUPERCELLS WITH ISOLD LARGE HAIL/WIND GUSTS
BEING THE PRIMARY HAZARDS.
FARTHER SE OVER THE MID MO VALLEY...THE TERMINUS OF A CNTRL PLAINS
30 KT LLJ WILL FOCUS OVER THE MID MO VALLEY THROUGHOUT THE DAY.
ALTHOUGH THIS REGION IS BENEATH THE UPPER RIDGE AXIS...AT LEAST A
LOW RISK FOR STORMS IS SUPPORTED BY VARIOUS OPERATIONAL MODELS.
GIVEN MODERATE INSTABILITY DEPICTED BY MODEL FORECAST SOUNDINGS...A
CONDITIONAL SEVERE AREA HAS BEEN INCLUDED THIS FORECAST UPDATE.
...PORTION OF THE SRN HIGH PLAINS...
A SELY LOW LEVEL FETCH OF MOISTURE LOCATED OVER THE SRN PLAINS IS
FORECAST TO MOVE WESTWARD INTO THE SRN HIGH PLAINS IN CONCERT WITH
THE LEE TROUGH...ABUTTING NEXT TO THE HIGHER TERRAIN IN W TX AND THE
ERN PLAINS OF NM. STEEP MID LEVEL LAPSE RATES EMANATING FROM THE W
AND STRONG DAYTIME HEATING WILL ACT TO FAVOR ISOLD STORM DEVELOPMENT
BY AFTERNOON...INITIALLY FAVORING HIGHER TERRAIN. DESPITE ONLY 20
KT WLY H5 FLOW...STRONGLY VEERING WIND PROFILES WOULD SUPPORT SOME
STORM ORGANIZATION FEATURING MAINLY HIGHER-BASED MULTICELLULAR
STORMS CAPABLE OF PERHAPS A FEW SEVERE WIND GUSTS AND MARGINALLY
SEVERE HAIL. THIS ACTIVITY SHOULD WEAKEN DURING THE EVENING HOURS
COINCIDENT WITH A STABILIZING BOUNDARY LAYER..
..SMITH.. 05/24/2013
000
ACUS02 KWNS 240553
SWODY2
SPC AC 240551
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CDT FRI MAY 24 2013
VALID 251200Z - 261200Z
...THERE IS A SLGT RISK OF SVR TSTMS FOR A PORTION OF ERN MT / FAR
NERN WY / WRN DAKOTAS...
...SYNOPSIS...
THE UPPER AIR PATTERN WILL FEATURE A WRN U.S. TROUGH/CNTRL U.S.
RIDGE/ERN U.S. TROUGH. DOWNSTREAM OF THE WRN STATES TROUGH...A
BROAD BELT OF MODERATE SWLY MID-LEVEL FLOW WILL OVERSPREAD THE NRN
HIGH PLAINS. A LEE SURFACE TROUGH OVER MUCH OF THE HIGH PLAINS WILL
SERVE AS A FOCUS FOR AFTERNOON/EVENING STORM DEVELOPMENT. FARTHER
E...A FRONTAL ZONE WILL EXTEND FROM THE ERN DAKOTAS TO THE MID MS
VALLEY TO THE WEST OF SURFACE HIGH PRESSURE CENTERED OVER THE GREAT
LAKES.
...NRN HIGH PLAINS INTO THE MID MO VALLEY...
NWD MOISTURE RETURN INTO THE CNTRL-NRN PLAINS ON THE BACKSIDE OF THE
MIDWEST SURFACE HIGH WILL BE ONGOING AT THE START OF THE DAY 2
PERIOD AS A CLOSED MID-LEVEL LOW REMAINS CENTERED OVER SRN BRITISH
COLUMBIA. THE LEE TROUGH LOCATED OVER CNTRL MT WILL ACT TO DRAW 50S
DEWPOINTS WESTWARD INTO ERN MT AND UPPER 50S DEWPOINTS INVOF THE
BLACK HILLS...CONTRIBUTING TO MARGINAL-MODERATE INSTABILITY. STRONG
DIURNAL HEATING WILL SEEMINGLY LEAD TO ISOLD TO WIDELY SCTD STORMS
IN THE LATE AFTERNOON-MID EVENING. DEEPLY VEERING WIND PROFILES
/40+ KT EFFECTIVE SHEAR/ WOULD SUPPORT STORM
ORGANIZATION...INCLUDING SUPERCELLS WITH ISOLD LARGE HAIL/WIND GUSTS
BEING THE PRIMARY HAZARDS.
FARTHER SE OVER THE MID MO VALLEY...THE TERMINUS OF A CNTRL PLAINS
30 KT LLJ WILL FOCUS OVER THE MID MO VALLEY THROUGHOUT THE DAY.
ALTHOUGH THIS REGION IS BENEATH THE UPPER RIDGE AXIS...AT LEAST A
LOW RISK FOR STORMS IS SUPPORTED BY VARIOUS OPERATIONAL MODELS.
GIVEN MODERATE INSTABILITY DEPICTED BY MODEL FORECAST SOUNDINGS...A
CONDITIONAL SEVERE AREA HAS BEEN INCLUDED THIS FORECAST UPDATE.
...PORTION OF THE SRN HIGH PLAINS...
A SELY LOW LEVEL FETCH OF MOISTURE LOCATED OVER THE SRN PLAINS IS
FORECAST TO MOVE WESTWARD INTO THE SRN HIGH PLAINS IN CONCERT WITH
THE LEE TROUGH...ABUTTING NEXT TO THE HIGHER TERRAIN IN W TX AND THE
ERN PLAINS OF NM. STEEP MID LEVEL LAPSE RATES EMANATING FROM THE W
AND STRONG DAYTIME HEATING WILL ACT TO FAVOR ISOLD STORM DEVELOPMENT
BY AFTERNOON...INITIALLY FAVORING HIGHER TERRAIN. DESPITE ONLY 20
KT WLY H5 FLOW...STRONGLY VEERING WIND PROFILES WOULD SUPPORT SOME
STORM ORGANIZATION FEATURING MAINLY HIGHER-BASED MULTICELLULAR
STORMS CAPABLE OF PERHAPS A FEW SEVERE WIND GUSTS AND MARGINALLY
SEVERE HAIL. THIS ACTIVITY SHOULD WEAKEN DURING THE EVENING HOURS
COINCIDENT WITH A STABILIZING BOUNDARY LAYER..
..SMITH.. 05/24/2013
000
ACUS11 KWNS 240416
SWOMCD
SPC MCD 240416
TXZ000-NMZ000-240545-
MESOSCALE DISCUSSION 0790
NWS STORM PREDICTION CENTER NORMAN OK
1116 PM CDT THU MAY 23 2013
AREAS AFFECTED...NE NM...W CENTRAL TX PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 240416Z - 240545Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...A FEW STORMS WILL LIKELY PERSIST FOR A COUPLE OF HOURS IN
THE MOIST UPSLOPE REGIME WITH AT LEAST A MARGINAL HAIL RISK.
HOWEVER...THE MAGNITUDE AND LONGEVITY OF THE THREAT SHOULD REMAIN
TOO SMALL TO WARRANT A WATCH.
DISCUSSION...OUTFLOW FROM EARLIER CONVECTION IN THE TX PANHANDLE HAS
SURGED WWD TO NEAR THE FRONT RANGE IN NM. THOUGH THE OUTFLOW AIR
MASS IS COOL...THE INCREASED DEW POINTS WITHIN THE OUTFLOW AND HIGH
ELEVATION ARE SUPPORTING MODERATE SURFACE-BASED INSTABILITY ACROSS
NE NM. VERTICAL SHEAR IS ALSO WITHIN THE RANGE AT LEAST MARGINALLY
FAVORABLE FOR SOME SUPERCELL STRUCTURES...GIVEN THE STRONG LOW-LEVEL
ELY COMPONENT. THE STRONGEST STORMS IN THIS ENVIRONMENT COULD
PRODUCE MARGINALLY SEVERE HAIL. HOWEVER...THE WINDOW OF OPPORTUNITY
FOR SEVERE STORMS WILL BE SOMEWHAT LIMITED AFTER THE INITIAL SURGE
OF MOISTURE AND AS THE BOUNDARY LAYER CONTINUES TO COOL
GRADUALLY...AND CONVECTIVE INHIBITION INCREASES. AT THIS TIME...THE
SEVERE STORM THREAT APPEARS TOO LIMITED TO WARRANT A WATCH.
..THOMPSON.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LUB...AMA...ABQ...
LAT...LON 36030300 35300245 34840220 34380261 34260348 34600455
35130527 35930530 36530474 36640397 36480343 36030300
000
ACUS11 KWNS 240416
SWOMCD
SPC MCD 240416
TXZ000-NMZ000-240545-
MESOSCALE DISCUSSION 0790
NWS STORM PREDICTION CENTER NORMAN OK
1116 PM CDT THU MAY 23 2013
AREAS AFFECTED...NE NM...W CENTRAL TX PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 240416Z - 240545Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...A FEW STORMS WILL LIKELY PERSIST FOR A COUPLE OF HOURS IN
THE MOIST UPSLOPE REGIME WITH AT LEAST A MARGINAL HAIL RISK.
HOWEVER...THE MAGNITUDE AND LONGEVITY OF THE THREAT SHOULD REMAIN
TOO SMALL TO WARRANT A WATCH.
DISCUSSION...OUTFLOW FROM EARLIER CONVECTION IN THE TX PANHANDLE HAS
SURGED WWD TO NEAR THE FRONT RANGE IN NM. THOUGH THE OUTFLOW AIR
MASS IS COOL...THE INCREASED DEW POINTS WITHIN THE OUTFLOW AND HIGH
ELEVATION ARE SUPPORTING MODERATE SURFACE-BASED INSTABILITY ACROSS
NE NM. VERTICAL SHEAR IS ALSO WITHIN THE RANGE AT LEAST MARGINALLY
FAVORABLE FOR SOME SUPERCELL STRUCTURES...GIVEN THE STRONG LOW-LEVEL
ELY COMPONENT. THE STRONGEST STORMS IN THIS ENVIRONMENT COULD
PRODUCE MARGINALLY SEVERE HAIL. HOWEVER...THE WINDOW OF OPPORTUNITY
FOR SEVERE STORMS WILL BE SOMEWHAT LIMITED AFTER THE INITIAL SURGE
OF MOISTURE AND AS THE BOUNDARY LAYER CONTINUES TO COOL
GRADUALLY...AND CONVECTIVE INHIBITION INCREASES. AT THIS TIME...THE
SEVERE STORM THREAT APPEARS TOO LIMITED TO WARRANT A WATCH.
..THOMPSON.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LUB...AMA...ABQ...
LAT...LON 36030300 35300245 34840220 34380261 34260348 34600455
35130527 35930530 36530474 36640397 36480343 36030300
000
ACUS11 KWNS 240416
SWOMCD
SPC MCD 240416
TXZ000-NMZ000-240545-
MESOSCALE DISCUSSION 0790
NWS STORM PREDICTION CENTER NORMAN OK
1116 PM CDT THU MAY 23 2013
AREAS AFFECTED...NE NM...W CENTRAL TX PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 240416Z - 240545Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...A FEW STORMS WILL LIKELY PERSIST FOR A COUPLE OF HOURS IN
THE MOIST UPSLOPE REGIME WITH AT LEAST A MARGINAL HAIL RISK.
HOWEVER...THE MAGNITUDE AND LONGEVITY OF THE THREAT SHOULD REMAIN
TOO SMALL TO WARRANT A WATCH.
DISCUSSION...OUTFLOW FROM EARLIER CONVECTION IN THE TX PANHANDLE HAS
SURGED WWD TO NEAR THE FRONT RANGE IN NM. THOUGH THE OUTFLOW AIR
MASS IS COOL...THE INCREASED DEW POINTS WITHIN THE OUTFLOW AND HIGH
ELEVATION ARE SUPPORTING MODERATE SURFACE-BASED INSTABILITY ACROSS
NE NM. VERTICAL SHEAR IS ALSO WITHIN THE RANGE AT LEAST MARGINALLY
FAVORABLE FOR SOME SUPERCELL STRUCTURES...GIVEN THE STRONG LOW-LEVEL
ELY COMPONENT. THE STRONGEST STORMS IN THIS ENVIRONMENT COULD
PRODUCE MARGINALLY SEVERE HAIL. HOWEVER...THE WINDOW OF OPPORTUNITY
FOR SEVERE STORMS WILL BE SOMEWHAT LIMITED AFTER THE INITIAL SURGE
OF MOISTURE AND AS THE BOUNDARY LAYER CONTINUES TO COOL
GRADUALLY...AND CONVECTIVE INHIBITION INCREASES. AT THIS TIME...THE
SEVERE STORM THREAT APPEARS TOO LIMITED TO WARRANT A WATCH.
..THOMPSON.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LUB...AMA...ABQ...
LAT...LON 36030300 35300245 34840220 34380261 34260348 34600455
35130527 35930530 36530474 36640397 36480343 36030300
000
ACUS11 KWNS 240253
SWOMCD
SPC MCD 240253
TXZ000-240400-
MESOSCALE DISCUSSION 0789
NWS STORM PREDICTION CENTER NORMAN OK
0953 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF SOUTHWEST/WEST-CENTRAL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240253Z - 240400Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...DAMAGING WINDS/BOUTS OF SEVERE HAIL REMAIN A POSSIBILITY
ACROSS PORTIONS OF SOUTHWEST/WEST-CENTRAL TX LATE THIS
EVENING...ALTHOUGH THE OVERALL INTENSITY SHOULD GRADUALLY WANE INTO
THE OVERNIGHT.
DISCUSSION...A 125-MILE WIDE COMPOSITE MCS CONTINUES TO GRADUALLY
DEVELOP SOUTHWARD...ROUGHLY NEAR TO AROUND 50 MILES SOUTH OF I-20
ACROSS SOUTHWEST/WEST-CENTRAL TX. COLLIDING OUTFLOWS ALONG WITH WEAK
ISENTROPIC ASCENT AND SLIGHTLY ELEVATED/MODERATELY STRONG STORM
RELATIVE INFLOW CONTINUES TO FOSTER NEW UPDRAFT DEVELOPMENT...WITH
SOME OF THE STRONGER CORES CONTINUING TO POSE A PROBABLE DAMAGING
WIND/SEVERE HAIL THREAT. WHILE A SEMI-ORGANIZED/SUSTAINED SOUTHWARD
PROPAGATION WILL LIKELY CONTINUE...A GRADUALLY COOLING BOUNDARY
LAYER AND WEAKER DEEP LAYER SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
SHOULD LEAD TO A DIMINISHING INTENSITY/ORGANIZATIONAL TREND OVER THE
NEXT COUPLE OF HOURS.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 29950183 30720230 31720251 31940201 31800118 31909904
31029895 30349998 29950183
000
ACUS11 KWNS 240253
SWOMCD
SPC MCD 240253
TXZ000-240400-
MESOSCALE DISCUSSION 0789
NWS STORM PREDICTION CENTER NORMAN OK
0953 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF SOUTHWEST/WEST-CENTRAL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240253Z - 240400Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...DAMAGING WINDS/BOUTS OF SEVERE HAIL REMAIN A POSSIBILITY
ACROSS PORTIONS OF SOUTHWEST/WEST-CENTRAL TX LATE THIS
EVENING...ALTHOUGH THE OVERALL INTENSITY SHOULD GRADUALLY WANE INTO
THE OVERNIGHT.
DISCUSSION...A 125-MILE WIDE COMPOSITE MCS CONTINUES TO GRADUALLY
DEVELOP SOUTHWARD...ROUGHLY NEAR TO AROUND 50 MILES SOUTH OF I-20
ACROSS SOUTHWEST/WEST-CENTRAL TX. COLLIDING OUTFLOWS ALONG WITH WEAK
ISENTROPIC ASCENT AND SLIGHTLY ELEVATED/MODERATELY STRONG STORM
RELATIVE INFLOW CONTINUES TO FOSTER NEW UPDRAFT DEVELOPMENT...WITH
SOME OF THE STRONGER CORES CONTINUING TO POSE A PROBABLE DAMAGING
WIND/SEVERE HAIL THREAT. WHILE A SEMI-ORGANIZED/SUSTAINED SOUTHWARD
PROPAGATION WILL LIKELY CONTINUE...A GRADUALLY COOLING BOUNDARY
LAYER AND WEAKER DEEP LAYER SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
SHOULD LEAD TO A DIMINISHING INTENSITY/ORGANIZATIONAL TREND OVER THE
NEXT COUPLE OF HOURS.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 29950183 30720230 31720251 31940201 31800118 31909904
31029895 30349998 29950183
000
ACUS11 KWNS 240253
SWOMCD
SPC MCD 240253
TXZ000-240400-
MESOSCALE DISCUSSION 0789
NWS STORM PREDICTION CENTER NORMAN OK
0953 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF SOUTHWEST/WEST-CENTRAL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240253Z - 240400Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...DAMAGING WINDS/BOUTS OF SEVERE HAIL REMAIN A POSSIBILITY
ACROSS PORTIONS OF SOUTHWEST/WEST-CENTRAL TX LATE THIS
EVENING...ALTHOUGH THE OVERALL INTENSITY SHOULD GRADUALLY WANE INTO
THE OVERNIGHT.
DISCUSSION...A 125-MILE WIDE COMPOSITE MCS CONTINUES TO GRADUALLY
DEVELOP SOUTHWARD...ROUGHLY NEAR TO AROUND 50 MILES SOUTH OF I-20
ACROSS SOUTHWEST/WEST-CENTRAL TX. COLLIDING OUTFLOWS ALONG WITH WEAK
ISENTROPIC ASCENT AND SLIGHTLY ELEVATED/MODERATELY STRONG STORM
RELATIVE INFLOW CONTINUES TO FOSTER NEW UPDRAFT DEVELOPMENT...WITH
SOME OF THE STRONGER CORES CONTINUING TO POSE A PROBABLE DAMAGING
WIND/SEVERE HAIL THREAT. WHILE A SEMI-ORGANIZED/SUSTAINED SOUTHWARD
PROPAGATION WILL LIKELY CONTINUE...A GRADUALLY COOLING BOUNDARY
LAYER AND WEAKER DEEP LAYER SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
SHOULD LEAD TO A DIMINISHING INTENSITY/ORGANIZATIONAL TREND OVER THE
NEXT COUPLE OF HOURS.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 29950183 30720230 31720251 31940201 31800118 31909904
31029895 30349998 29950183
000
ACUS01 KWNS 240100
SWODY1
SPC AC 240058
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0758 PM CDT THU MAY 23 2013
VALID 240100Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF WRN TX...
...WRN TX...
CLUSTER OF STORMS OVER THE SOUTH PLAINS OF WEST TX WILL LIKELY
CONTINUE TO POSE A THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL
THROUGH MID EVENING. ACTIVITY SHOULD PROPAGATE SEWD INTO THE MOIST
AND UNSTABLE INFLOW AND MAY EVENTUALLY MERGE WITH OUTFLOWS FROM
STORMS SPREADING NEWD FROM SWRN TX. A FEW STORMS MAY ALSO CONTINUE
DEVELOPING ON THE COOL SIDE OF THIS BOUNDARY IN THE LUBBOCK VICINITY
AS THE LLJ STRENGTHENS. THE 00Z RAOB DATA SUGGEST STORMS SHOULD
BEGIN TO STRUGGLE LATER THIS EVENING AS THE BOUNDARY LAYER COOLS AND
CONVECTIVE INHIBITION INCREASES.
...MID ATLANTIC THROUGH NERN STATES...
NUMEROUS MULTICELL STORMS WITH LINES AND CLUSTERS WILL PERSIST
THROUGH THE MARGINALLY UNSTABLE WARM SECTOR THIS EVENING. THE
STRONGER STORMS MAY POSE A MODEST RISK FOR ISOLATED STRONG WIND
GUSTS THROUGH 03Z...BUT ACTIVITY IS EXPECTED TO UNDERGO A GRADUAL
DECREASE AS THE BOUNDARY LAYER COOLS.
..DIAL.. 05/24/2013
000
ACUS01 KWNS 240100
SWODY1
SPC AC 240058
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0758 PM CDT THU MAY 23 2013
VALID 240100Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF WRN TX...
...WRN TX...
CLUSTER OF STORMS OVER THE SOUTH PLAINS OF WEST TX WILL LIKELY
CONTINUE TO POSE A THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL
THROUGH MID EVENING. ACTIVITY SHOULD PROPAGATE SEWD INTO THE MOIST
AND UNSTABLE INFLOW AND MAY EVENTUALLY MERGE WITH OUTFLOWS FROM
STORMS SPREADING NEWD FROM SWRN TX. A FEW STORMS MAY ALSO CONTINUE
DEVELOPING ON THE COOL SIDE OF THIS BOUNDARY IN THE LUBBOCK VICINITY
AS THE LLJ STRENGTHENS. THE 00Z RAOB DATA SUGGEST STORMS SHOULD
BEGIN TO STRUGGLE LATER THIS EVENING AS THE BOUNDARY LAYER COOLS AND
CONVECTIVE INHIBITION INCREASES.
...MID ATLANTIC THROUGH NERN STATES...
NUMEROUS MULTICELL STORMS WITH LINES AND CLUSTERS WILL PERSIST
THROUGH THE MARGINALLY UNSTABLE WARM SECTOR THIS EVENING. THE
STRONGER STORMS MAY POSE A MODEST RISK FOR ISOLATED STRONG WIND
GUSTS THROUGH 03Z...BUT ACTIVITY IS EXPECTED TO UNDERGO A GRADUAL
DECREASE AS THE BOUNDARY LAYER COOLS.
..DIAL.. 05/24/2013
000
ACUS11 KWNS 240036
SWOMCD
SPC MCD 240035
TXZ000-NMZ000-240200-
MESOSCALE DISCUSSION 0788
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT THU MAY 23 2013
AREAS AFFECTED...SOUTHWEST TX/FAR SOUTHEAST NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240035Z - 240200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...SEVERE TSTM WATCH 214 CONTINUES UNTIL 03Z...WITH BOUTS OF
SEVERE HAIL/WIND REMAINING POSSIBLE MAINLY ACROSS THE TX LOW ROLLING
PLAINS/EDWARDS PLATEAU.
DISCUSSION...THE AIRMASS HAS GENERALLY BEEN CONVECTIVELY OVERTURNED
WITHIN THE WESTERN HALF OF WW 214 ACROSS FAR SOUTHWEST TX/TRANSPECOS
REGION AND FAR SOUTHEAST NM...WITH TEMPERATURES ELSEWHERE ACROSS
SOUTHWEST TX OTHERWISE BEGINNING TO COOL VIA ANVIL
SHADING/APPROACHING SUNSET. THE PRIMARY LINGERING SEVERE THREAT WILL
BE BETWEEN FORT STOCKTON AND THE RIO GRANDE...AND MORE SO ALONG THE
I-20 CORRIDOR WITH A BACK-BUILDING/SOUTH-SOUTHWESTWARD PROPAGATING
MCS. HERE...DAMAGING WINDS AND SOME SEVERE HAIL /MAINLY WESTERN
FLANK/ WILL REMAIN POSSIBLE ASIDE FROM HEAVY RAINFALL. MEASURED WIND
GUSTS OF 52 KT HAVE BEEN NOTED WITHIN THE PAST HOUR AT BOTH SNYDER
TX AND DYESS AIR FORCE BASE/ABILENE.
ON THE SOUTHWEST PERIPHERY OF THIS MCS...THE 00Z OBSERVED SOUNDING
FROM MIDLAND SAMPLED AROUND 2600 J/KG OF MLCAPE VIA VERY STEEP LAPSE
RATES /9.0 C PER KM 700-500 MB/ COINCIDENT WITH A LOWER 60S F
SURFACE DEWPOINT AND MEAN MIXING RATIO AROUND 11.8 G/KG.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 30150284 31970331 32470192 32190044 31679983 29650110
30150284
000
ACUS11 KWNS 240036
SWOMCD
SPC MCD 240035
TXZ000-NMZ000-240200-
MESOSCALE DISCUSSION 0788
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT THU MAY 23 2013
AREAS AFFECTED...SOUTHWEST TX/FAR SOUTHEAST NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240035Z - 240200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...SEVERE TSTM WATCH 214 CONTINUES UNTIL 03Z...WITH BOUTS OF
SEVERE HAIL/WIND REMAINING POSSIBLE MAINLY ACROSS THE TX LOW ROLLING
PLAINS/EDWARDS PLATEAU.
DISCUSSION...THE AIRMASS HAS GENERALLY BEEN CONVECTIVELY OVERTURNED
WITHIN THE WESTERN HALF OF WW 214 ACROSS FAR SOUTHWEST TX/TRANSPECOS
REGION AND FAR SOUTHEAST NM...WITH TEMPERATURES ELSEWHERE ACROSS
SOUTHWEST TX OTHERWISE BEGINNING TO COOL VIA ANVIL
SHADING/APPROACHING SUNSET. THE PRIMARY LINGERING SEVERE THREAT WILL
BE BETWEEN FORT STOCKTON AND THE RIO GRANDE...AND MORE SO ALONG THE
I-20 CORRIDOR WITH A BACK-BUILDING/SOUTH-SOUTHWESTWARD PROPAGATING
MCS. HERE...DAMAGING WINDS AND SOME SEVERE HAIL /MAINLY WESTERN
FLANK/ WILL REMAIN POSSIBLE ASIDE FROM HEAVY RAINFALL. MEASURED WIND
GUSTS OF 52 KT HAVE BEEN NOTED WITHIN THE PAST HOUR AT BOTH SNYDER
TX AND DYESS AIR FORCE BASE/ABILENE.
ON THE SOUTHWEST PERIPHERY OF THIS MCS...THE 00Z OBSERVED SOUNDING
FROM MIDLAND SAMPLED AROUND 2600 J/KG OF MLCAPE VIA VERY STEEP LAPSE
RATES /9.0 C PER KM 700-500 MB/ COINCIDENT WITH A LOWER 60S F
SURFACE DEWPOINT AND MEAN MIXING RATIO AROUND 11.8 G/KG.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 30150284 31970331 32470192 32190044 31679983 29650110
30150284
000
ACUS11 KWNS 240036
SWOMCD
SPC MCD 240035
TXZ000-NMZ000-240200-
MESOSCALE DISCUSSION 0788
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT THU MAY 23 2013
AREAS AFFECTED...SOUTHWEST TX/FAR SOUTHEAST NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 240035Z - 240200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...SEVERE TSTM WATCH 214 CONTINUES UNTIL 03Z...WITH BOUTS OF
SEVERE HAIL/WIND REMAINING POSSIBLE MAINLY ACROSS THE TX LOW ROLLING
PLAINS/EDWARDS PLATEAU.
DISCUSSION...THE AIRMASS HAS GENERALLY BEEN CONVECTIVELY OVERTURNED
WITHIN THE WESTERN HALF OF WW 214 ACROSS FAR SOUTHWEST TX/TRANSPECOS
REGION AND FAR SOUTHEAST NM...WITH TEMPERATURES ELSEWHERE ACROSS
SOUTHWEST TX OTHERWISE BEGINNING TO COOL VIA ANVIL
SHADING/APPROACHING SUNSET. THE PRIMARY LINGERING SEVERE THREAT WILL
BE BETWEEN FORT STOCKTON AND THE RIO GRANDE...AND MORE SO ALONG THE
I-20 CORRIDOR WITH A BACK-BUILDING/SOUTH-SOUTHWESTWARD PROPAGATING
MCS. HERE...DAMAGING WINDS AND SOME SEVERE HAIL /MAINLY WESTERN
FLANK/ WILL REMAIN POSSIBLE ASIDE FROM HEAVY RAINFALL. MEASURED WIND
GUSTS OF 52 KT HAVE BEEN NOTED WITHIN THE PAST HOUR AT BOTH SNYDER
TX AND DYESS AIR FORCE BASE/ABILENE.
ON THE SOUTHWEST PERIPHERY OF THIS MCS...THE 00Z OBSERVED SOUNDING
FROM MIDLAND SAMPLED AROUND 2600 J/KG OF MLCAPE VIA VERY STEEP LAPSE
RATES /9.0 C PER KM 700-500 MB/ COINCIDENT WITH A LOWER 60S F
SURFACE DEWPOINT AND MEAN MIXING RATIO AROUND 11.8 G/KG.
..GUYER.. 05/24/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 30150284 31970331 32470192 32190044 31679983 29650110
30150284
000
ACUS11 KWNS 232348
SWOMCD
SPC MCD 232347
MTZ000-WYZ000-240115-
MESOSCALE DISCUSSION 0787
NWS STORM PREDICTION CENTER NORMAN OK
0647 PM CDT THU MAY 23 2013
AREAS AFFECTED...FAR SOUTH-CENTRAL MT
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 232347Z - 240115Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...ISOLATED BOUTS OF SEVERE HAIL/GUSTY WINDS WILL BE POSSIBLE
THROUGH EARLY/PERHAPS MID-EVENING ACROSS PORTIONS OF
SOUTH-CENTRAL/SOUTHEAST MT...POTENTIALLY INCLUDING PARTS OF THE I-90
CORRIDOR/BILLINGS VICINITY.
DISCUSSION...SCATTERED TSTMS WILL LIKELY CONTINUE TO MOVE GENERALLY
NORTHWARD FROM THE MT/WY BORDER VICINITY/BIGHORNS INTO PARTS OF
SOUTH-CENTRAL/NEARBY SOUTHEAST MT THIS EVENING. WHILE CAPE IS NOT
ROBUST /MLCAPE 500-800 J PER KG OR LESS/ AMID 40S F SURFACE
DEWPOINTS...STEEP LAPSE RATES ALOFT AND STRONG/DEEP
SOUTH-SOUTHWESTERLY FLOW /ON PERIPHERY OF PACIFIC NORTHWEST TROUGH/
ATOP LIGHTER NEAR-SURFACE WINDS WILL SUPPORT SOME SUSTAINED
UPDRAFTS/SMALLER SUPERCELL STRUCTURES CAPABLE OF SEVERE HAIL TO
AROUND 1 INCH IN DIAMETER. THIS DEVELOPMENT MAY REACH PORTIONS OF
THE I-90 CORRIDOR/BILLINGS VICINITY TOWARD 01Z. THE PERCEIVED
MARGINAL/ISOLATED NATURE OF THE SEVERE RISK WILL LIKELY PRECLUDE A
WATCH ISSUANCE.
..GUYER/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BYZ...RIW...
LAT...LON 45140787 44940884 45130956 45770975 46510904 46040783
45140787
000
ACUS11 KWNS 232348
SWOMCD
SPC MCD 232347
MTZ000-WYZ000-240115-
MESOSCALE DISCUSSION 0787
NWS STORM PREDICTION CENTER NORMAN OK
0647 PM CDT THU MAY 23 2013
AREAS AFFECTED...FAR SOUTH-CENTRAL MT
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 232347Z - 240115Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...ISOLATED BOUTS OF SEVERE HAIL/GUSTY WINDS WILL BE POSSIBLE
THROUGH EARLY/PERHAPS MID-EVENING ACROSS PORTIONS OF
SOUTH-CENTRAL/SOUTHEAST MT...POTENTIALLY INCLUDING PARTS OF THE I-90
CORRIDOR/BILLINGS VICINITY.
DISCUSSION...SCATTERED TSTMS WILL LIKELY CONTINUE TO MOVE GENERALLY
NORTHWARD FROM THE MT/WY BORDER VICINITY/BIGHORNS INTO PARTS OF
SOUTH-CENTRAL/NEARBY SOUTHEAST MT THIS EVENING. WHILE CAPE IS NOT
ROBUST /MLCAPE 500-800 J PER KG OR LESS/ AMID 40S F SURFACE
DEWPOINTS...STEEP LAPSE RATES ALOFT AND STRONG/DEEP
SOUTH-SOUTHWESTERLY FLOW /ON PERIPHERY OF PACIFIC NORTHWEST TROUGH/
ATOP LIGHTER NEAR-SURFACE WINDS WILL SUPPORT SOME SUSTAINED
UPDRAFTS/SMALLER SUPERCELL STRUCTURES CAPABLE OF SEVERE HAIL TO
AROUND 1 INCH IN DIAMETER. THIS DEVELOPMENT MAY REACH PORTIONS OF
THE I-90 CORRIDOR/BILLINGS VICINITY TOWARD 01Z. THE PERCEIVED
MARGINAL/ISOLATED NATURE OF THE SEVERE RISK WILL LIKELY PRECLUDE A
WATCH ISSUANCE.
..GUYER/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BYZ...RIW...
LAT...LON 45140787 44940884 45130956 45770975 46510904 46040783
45140787
000
ACUS11 KWNS 232348
SWOMCD
SPC MCD 232347
MTZ000-WYZ000-240115-
MESOSCALE DISCUSSION 0787
NWS STORM PREDICTION CENTER NORMAN OK
0647 PM CDT THU MAY 23 2013
AREAS AFFECTED...FAR SOUTH-CENTRAL MT
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 232347Z - 240115Z
PROBABILITY OF WATCH ISSUANCE...5 PERCENT
SUMMARY...ISOLATED BOUTS OF SEVERE HAIL/GUSTY WINDS WILL BE POSSIBLE
THROUGH EARLY/PERHAPS MID-EVENING ACROSS PORTIONS OF
SOUTH-CENTRAL/SOUTHEAST MT...POTENTIALLY INCLUDING PARTS OF THE I-90
CORRIDOR/BILLINGS VICINITY.
DISCUSSION...SCATTERED TSTMS WILL LIKELY CONTINUE TO MOVE GENERALLY
NORTHWARD FROM THE MT/WY BORDER VICINITY/BIGHORNS INTO PARTS OF
SOUTH-CENTRAL/NEARBY SOUTHEAST MT THIS EVENING. WHILE CAPE IS NOT
ROBUST /MLCAPE 500-800 J PER KG OR LESS/ AMID 40S F SURFACE
DEWPOINTS...STEEP LAPSE RATES ALOFT AND STRONG/DEEP
SOUTH-SOUTHWESTERLY FLOW /ON PERIPHERY OF PACIFIC NORTHWEST TROUGH/
ATOP LIGHTER NEAR-SURFACE WINDS WILL SUPPORT SOME SUSTAINED
UPDRAFTS/SMALLER SUPERCELL STRUCTURES CAPABLE OF SEVERE HAIL TO
AROUND 1 INCH IN DIAMETER. THIS DEVELOPMENT MAY REACH PORTIONS OF
THE I-90 CORRIDOR/BILLINGS VICINITY TOWARD 01Z. THE PERCEIVED
MARGINAL/ISOLATED NATURE OF THE SEVERE RISK WILL LIKELY PRECLUDE A
WATCH ISSUANCE.
..GUYER/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BYZ...RIW...
LAT...LON 45140787 44940884 45130956 45770975 46510904 46040783
45140787
000
ACUS11 KWNS 232310
SWOMCD
SPC MCD 232310
TXZ000-240045-
MESOSCALE DISCUSSION 0786
NWS STORM PREDICTION CENTER NORMAN OK
0610 PM CDT THU MAY 23 2013
AREAS AFFECTED...TX PANHANDLE/NORTHWEST TX AND FAR WESTERN OK
CONCERNING...TORNADO WATCH 213...
VALID 232310Z - 240045Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...TORNADO WATCH 213 CONTINUES...WITH A LESSENING TORNADO
POTENTIAL ASIDE FROM LARGE HAIL AND WHAT SHOULD BE AN INCREASING
DAMAGING WIND THREAT ESPECIALLY ACROSS THE LOW ROLLING PLAINS OF TX.
PORTIONS OF WATCHES 213 AND/OR 214 MAY WARRANT A SPATIAL WATCH
EXTENSION.
DISCUSSION...SUPERCELL MERGERS APPEAR TO ALREADY BE LEADING TO
UPSCALE CONVECTIVE GROWTH ACROSS THE NORTHWEST TX LOW ROLLING
PLAINS...ROUGHLY 50 MILES TO THE NORTH OF I-20 AND
SWEETWATER/ABILENE AREAS AS OF 2245Z. ALTHOUGH SOME TORNADO THREAT
MAY CONTINUE...MAINLY WITH SEMI-DISCRETE/INITIAL-MERGER
DEVELOPMENT...A MORE MODEST SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
AND CONTINUED CELL MERGERS WILL LIKELY CONTINUE TO LEAD TO
UPSCALE/MCS DEVELOPMENT. ACCORDINGLY...AT LEAST A LOCALIZED
DAMAGING WIND THREAT SHOULD INCREASE WITH A CONTINUED
SOUTH-SOUTHEASTWARD PROPAGATION/GRADUAL ACCELERATION TOWARD/ACROSS
I-20...INCLUDING THE SNYDER/SWEETWATER/ABILENE AREAS. SOME INCREASE
IN SOUTHEASTERLY WINDS BETWEEN 1-2 KM AT WSR-88D VWP DATA FROM DYESS
AFB/SAN ANGELO OVER THE PAST HOUR OR TWO SUPPORT THE NOTION OF
INCREASING STORM-RELATIVE INFLOW/SUSTAINED PROPAGATION.
FARTHER NORTHWEST...A MERGER BETWEEN WEST-NORTHWESTWARD MOVING
OUTFLOW AND FRONTAL BOUNDARY HAS CONTRIBUTED TO ADDITIONAL
DEVELOPMENT JUST NORTH-NORTHWEST OF THE AMARILLO AREA AS OF 2245Z. A
SPECIAL 21Z OBSERVED SOUNDING SAMPLED A VERY STEEP ELEVATED LAPSE
RATE PROFILE WITH AN ADJUSTED 2500+ J/KG OF MLCAPE WITHIN A VEERING
WIND PROFILE /45-50 KT OF EFFECTIVE SHEAR/. LARGE HAIL WILL THE
PRIMARY HAZARD...ALTHOUGH SOME TORNADO THREAT MAY EXIST AS WELL
SHOULD RIGHT-MOVING SUPERCELLS DEVELOP/PERSIST ALBEIT WITHIN A
SOMEWHAT COOLER/OUTFLOW INFLUENCED ENVIRONMENT.
..GUYER.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF...
LAT...LON 35550245 35800077 33899978 33289881 31799921 32790198
35550245
000
ACUS11 KWNS 232310
SWOMCD
SPC MCD 232310
TXZ000-240045-
MESOSCALE DISCUSSION 0786
NWS STORM PREDICTION CENTER NORMAN OK
0610 PM CDT THU MAY 23 2013
AREAS AFFECTED...TX PANHANDLE/NORTHWEST TX AND FAR WESTERN OK
CONCERNING...TORNADO WATCH 213...
VALID 232310Z - 240045Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...TORNADO WATCH 213 CONTINUES...WITH A LESSENING TORNADO
POTENTIAL ASIDE FROM LARGE HAIL AND WHAT SHOULD BE AN INCREASING
DAMAGING WIND THREAT ESPECIALLY ACROSS THE LOW ROLLING PLAINS OF TX.
PORTIONS OF WATCHES 213 AND/OR 214 MAY WARRANT A SPATIAL WATCH
EXTENSION.
DISCUSSION...SUPERCELL MERGERS APPEAR TO ALREADY BE LEADING TO
UPSCALE CONVECTIVE GROWTH ACROSS THE NORTHWEST TX LOW ROLLING
PLAINS...ROUGHLY 50 MILES TO THE NORTH OF I-20 AND
SWEETWATER/ABILENE AREAS AS OF 2245Z. ALTHOUGH SOME TORNADO THREAT
MAY CONTINUE...MAINLY WITH SEMI-DISCRETE/INITIAL-MERGER
DEVELOPMENT...A MORE MODEST SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
AND CONTINUED CELL MERGERS WILL LIKELY CONTINUE TO LEAD TO
UPSCALE/MCS DEVELOPMENT. ACCORDINGLY...AT LEAST A LOCALIZED
DAMAGING WIND THREAT SHOULD INCREASE WITH A CONTINUED
SOUTH-SOUTHEASTWARD PROPAGATION/GRADUAL ACCELERATION TOWARD/ACROSS
I-20...INCLUDING THE SNYDER/SWEETWATER/ABILENE AREAS. SOME INCREASE
IN SOUTHEASTERLY WINDS BETWEEN 1-2 KM AT WSR-88D VWP DATA FROM DYESS
AFB/SAN ANGELO OVER THE PAST HOUR OR TWO SUPPORT THE NOTION OF
INCREASING STORM-RELATIVE INFLOW/SUSTAINED PROPAGATION.
FARTHER NORTHWEST...A MERGER BETWEEN WEST-NORTHWESTWARD MOVING
OUTFLOW AND FRONTAL BOUNDARY HAS CONTRIBUTED TO ADDITIONAL
DEVELOPMENT JUST NORTH-NORTHWEST OF THE AMARILLO AREA AS OF 2245Z. A
SPECIAL 21Z OBSERVED SOUNDING SAMPLED A VERY STEEP ELEVATED LAPSE
RATE PROFILE WITH AN ADJUSTED 2500+ J/KG OF MLCAPE WITHIN A VEERING
WIND PROFILE /45-50 KT OF EFFECTIVE SHEAR/. LARGE HAIL WILL THE
PRIMARY HAZARD...ALTHOUGH SOME TORNADO THREAT MAY EXIST AS WELL
SHOULD RIGHT-MOVING SUPERCELLS DEVELOP/PERSIST ALBEIT WITHIN A
SOMEWHAT COOLER/OUTFLOW INFLUENCED ENVIRONMENT.
..GUYER.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF...
LAT...LON 35550245 35800077 33899978 33289881 31799921 32790198
35550245
000
ACUS11 KWNS 232310
SWOMCD
SPC MCD 232310
TXZ000-240045-
MESOSCALE DISCUSSION 0786
NWS STORM PREDICTION CENTER NORMAN OK
0610 PM CDT THU MAY 23 2013
AREAS AFFECTED...TX PANHANDLE/NORTHWEST TX AND FAR WESTERN OK
CONCERNING...TORNADO WATCH 213...
VALID 232310Z - 240045Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...TORNADO WATCH 213 CONTINUES...WITH A LESSENING TORNADO
POTENTIAL ASIDE FROM LARGE HAIL AND WHAT SHOULD BE AN INCREASING
DAMAGING WIND THREAT ESPECIALLY ACROSS THE LOW ROLLING PLAINS OF TX.
PORTIONS OF WATCHES 213 AND/OR 214 MAY WARRANT A SPATIAL WATCH
EXTENSION.
DISCUSSION...SUPERCELL MERGERS APPEAR TO ALREADY BE LEADING TO
UPSCALE CONVECTIVE GROWTH ACROSS THE NORTHWEST TX LOW ROLLING
PLAINS...ROUGHLY 50 MILES TO THE NORTH OF I-20 AND
SWEETWATER/ABILENE AREAS AS OF 2245Z. ALTHOUGH SOME TORNADO THREAT
MAY CONTINUE...MAINLY WITH SEMI-DISCRETE/INITIAL-MERGER
DEVELOPMENT...A MORE MODEST SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
AND CONTINUED CELL MERGERS WILL LIKELY CONTINUE TO LEAD TO
UPSCALE/MCS DEVELOPMENT. ACCORDINGLY...AT LEAST A LOCALIZED
DAMAGING WIND THREAT SHOULD INCREASE WITH A CONTINUED
SOUTH-SOUTHEASTWARD PROPAGATION/GRADUAL ACCELERATION TOWARD/ACROSS
I-20...INCLUDING THE SNYDER/SWEETWATER/ABILENE AREAS. SOME INCREASE
IN SOUTHEASTERLY WINDS BETWEEN 1-2 KM AT WSR-88D VWP DATA FROM DYESS
AFB/SAN ANGELO OVER THE PAST HOUR OR TWO SUPPORT THE NOTION OF
INCREASING STORM-RELATIVE INFLOW/SUSTAINED PROPAGATION.
FARTHER NORTHWEST...A MERGER BETWEEN WEST-NORTHWESTWARD MOVING
OUTFLOW AND FRONTAL BOUNDARY HAS CONTRIBUTED TO ADDITIONAL
DEVELOPMENT JUST NORTH-NORTHWEST OF THE AMARILLO AREA AS OF 2245Z. A
SPECIAL 21Z OBSERVED SOUNDING SAMPLED A VERY STEEP ELEVATED LAPSE
RATE PROFILE WITH AN ADJUSTED 2500+ J/KG OF MLCAPE WITHIN A VEERING
WIND PROFILE /45-50 KT OF EFFECTIVE SHEAR/. LARGE HAIL WILL THE
PRIMARY HAZARD...ALTHOUGH SOME TORNADO THREAT MAY EXIST AS WELL
SHOULD RIGHT-MOVING SUPERCELLS DEVELOP/PERSIST ALBEIT WITHIN A
SOMEWHAT COOLER/OUTFLOW INFLUENCED ENVIRONMENT.
..GUYER.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF...
LAT...LON 35550245 35800077 33899978 33289881 31799921 32790198
35550245
000
ACUS11 KWNS 232047
SWOMCD
SPC MCD 232046
TXZ000-NMZ000-232145-
MESOSCALE DISCUSSION 0785
NWS STORM PREDICTION CENTER NORMAN OK
0346 PM CDT THU MAY 23 2013
AREAS AFFECTED...WRN TX...FAR SERN NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 232046Z - 232145Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...ISOLATED SEVERE WIND/HAIL HAZARDS WILL PERSIST ACROSS THE
TRANS-PECOS AND POSSIBLY DEVELOP INTO THE PERMIAN BASIN OVER THE
NEXT FEW HOURS.
DISCUSSION...SCATTERED TSTMS HAVE BEEN SLOW TO MOVE EWD ACROSS THE
PECOS VALLEY WITHIN A WEAK DEEP-LAYER FLOW REGIME.
NEVERTHELESS...WITH LOW-LEVEL UPSLOPE FLOW PERSISTING AND CONVECTION
CONTINUING TO INCREASE ACROSS THE HIGHER TERRAIN IT APPEARS PROBABLE
THAT A MULTICELL CLUSTER MAY EVENTUALLY EMANATE EWD INTO PARTS OF
THE PERMIAN BASIN. SHOULD THIS OCCUR...35-55 DEG F SURFACE
TEMPERATURE/DEW POINT SPREADS WILL ENHANCE POTENTIAL FOR SEVERE WIND
GUSTS AMIDST A CONTINUING RISK OF LARGE HAIL.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...EPZ...
LAT...LON 32840421 32870349 32600307 31740184 30960146 29920153
29400238 28870306 30050488 31230533 32710463 32840421
000
ACUS11 KWNS 232047
SWOMCD
SPC MCD 232046
TXZ000-NMZ000-232145-
MESOSCALE DISCUSSION 0785
NWS STORM PREDICTION CENTER NORMAN OK
0346 PM CDT THU MAY 23 2013
AREAS AFFECTED...WRN TX...FAR SERN NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 232046Z - 232145Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...ISOLATED SEVERE WIND/HAIL HAZARDS WILL PERSIST ACROSS THE
TRANS-PECOS AND POSSIBLY DEVELOP INTO THE PERMIAN BASIN OVER THE
NEXT FEW HOURS.
DISCUSSION...SCATTERED TSTMS HAVE BEEN SLOW TO MOVE EWD ACROSS THE
PECOS VALLEY WITHIN A WEAK DEEP-LAYER FLOW REGIME.
NEVERTHELESS...WITH LOW-LEVEL UPSLOPE FLOW PERSISTING AND CONVECTION
CONTINUING TO INCREASE ACROSS THE HIGHER TERRAIN IT APPEARS PROBABLE
THAT A MULTICELL CLUSTER MAY EVENTUALLY EMANATE EWD INTO PARTS OF
THE PERMIAN BASIN. SHOULD THIS OCCUR...35-55 DEG F SURFACE
TEMPERATURE/DEW POINT SPREADS WILL ENHANCE POTENTIAL FOR SEVERE WIND
GUSTS AMIDST A CONTINUING RISK OF LARGE HAIL.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...EPZ...
LAT...LON 32840421 32870349 32600307 31740184 30960146 29920153
29400238 28870306 30050488 31230533 32710463 32840421
000
ACUS11 KWNS 232047
SWOMCD
SPC MCD 232046
TXZ000-NMZ000-232145-
MESOSCALE DISCUSSION 0785
NWS STORM PREDICTION CENTER NORMAN OK
0346 PM CDT THU MAY 23 2013
AREAS AFFECTED...WRN TX...FAR SERN NM
CONCERNING...SEVERE THUNDERSTORM WATCH 214...
VALID 232046Z - 232145Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 214
CONTINUES.
SUMMARY...ISOLATED SEVERE WIND/HAIL HAZARDS WILL PERSIST ACROSS THE
TRANS-PECOS AND POSSIBLY DEVELOP INTO THE PERMIAN BASIN OVER THE
NEXT FEW HOURS.
DISCUSSION...SCATTERED TSTMS HAVE BEEN SLOW TO MOVE EWD ACROSS THE
PECOS VALLEY WITHIN A WEAK DEEP-LAYER FLOW REGIME.
NEVERTHELESS...WITH LOW-LEVEL UPSLOPE FLOW PERSISTING AND CONVECTION
CONTINUING TO INCREASE ACROSS THE HIGHER TERRAIN IT APPEARS PROBABLE
THAT A MULTICELL CLUSTER MAY EVENTUALLY EMANATE EWD INTO PARTS OF
THE PERMIAN BASIN. SHOULD THIS OCCUR...35-55 DEG F SURFACE
TEMPERATURE/DEW POINT SPREADS WILL ENHANCE POTENTIAL FOR SEVERE WIND
GUSTS AMIDST A CONTINUING RISK OF LARGE HAIL.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...EWX...SJT...MAF...EPZ...
LAT...LON 32840421 32870349 32600307 31740184 30960146 29920153
29400238 28870306 30050488 31230533 32710463 32840421
000
ACUS11 KWNS 232033
SWOMCD
SPC MCD 232032
TXZ000-232200-
MESOSCALE DISCUSSION 0784
NWS STORM PREDICTION CENTER NORMAN OK
0332 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...TORNADO WATCH 213...
VALID 232032Z - 232200Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...GREATEST NEAR-TERM POTENTIAL FOR VERY LARGE HAIL...SEVERE
WINDS AND MESOCYCLONE TORNADOES SHOULD REMAIN WITH A SUPERCELL
CLUSTER IN THE ERN HALF OF THE LUB CWA. ADDITIONAL TSTMS MAY DEVELOP
BY 22Z ALONG THE OCCLUDED OUTFLOW/FRONT FARTHER NW IN THE WRN TX
PANHANDLE.
DISCUSSION...SUPERCELL OVER FLOYD COUNTY HAS PERSISTENTLY MOVED
SLOWLY SWD...WHILE ADDITIONAL UPDRAFTS HAVE FORMED SEWD ON THE COOL
SIDE OF THE INCREASINGLY DIFFUSE LARGER-SCALE OUTFLOW BOUNDARY. WITH
60S SURFACE DEW POINTS PERSISTING N/E OF THE OUTFLOW ACROSS THE LOW
ROLLING PLAINS INTO N-CNTRL TX /SAMPLED BY 20Z FWD RAOB/...AND
SURFACE TEMPERATURES S/W OF THE BOUNDARY FROM 95-100 DEG F...LARGE
INSTABILITY WILL REMAIN FAVORABLE FOR ALL SEVERE HAZARDS WITH
ACTIVITY GRADUALLY SHIFTING S/SEWD.
FARTHER NW...INITIAL CONVECTIVE ATTEMPTS HAVE FAILED TO YIELD TSTMS
ALONG THE SLOWLY WWD-PROGRESSING OUTFLOW WHICH HAS ESSENTIALLY
OCCLUDED WITH THE REMNANT QUASI-STATIONARY FRONTAL ZONE. ALTHOUGH
TEMPERATURES ARE NOT QUITE AS WARM AS FARTHER S...REINFORCING
OUTFLOW FROM THE SUPERCELL CLUSTERS MAY YIELD SUSTAINABLE CONVECTIVE
DEVELOPMENT INTO THE WRN TX PANHANDLE.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34210044 33809969 33189959 32789978 32650017 32530071
32960149 33780214 34380237 35110256 35410245 35550224
35490202 35180199 34620190 34400163 34160095 34210044
000
ACUS11 KWNS 232033
SWOMCD
SPC MCD 232032
TXZ000-232200-
MESOSCALE DISCUSSION 0784
NWS STORM PREDICTION CENTER NORMAN OK
0332 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...TORNADO WATCH 213...
VALID 232032Z - 232200Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...GREATEST NEAR-TERM POTENTIAL FOR VERY LARGE HAIL...SEVERE
WINDS AND MESOCYCLONE TORNADOES SHOULD REMAIN WITH A SUPERCELL
CLUSTER IN THE ERN HALF OF THE LUB CWA. ADDITIONAL TSTMS MAY DEVELOP
BY 22Z ALONG THE OCCLUDED OUTFLOW/FRONT FARTHER NW IN THE WRN TX
PANHANDLE.
DISCUSSION...SUPERCELL OVER FLOYD COUNTY HAS PERSISTENTLY MOVED
SLOWLY SWD...WHILE ADDITIONAL UPDRAFTS HAVE FORMED SEWD ON THE COOL
SIDE OF THE INCREASINGLY DIFFUSE LARGER-SCALE OUTFLOW BOUNDARY. WITH
60S SURFACE DEW POINTS PERSISTING N/E OF THE OUTFLOW ACROSS THE LOW
ROLLING PLAINS INTO N-CNTRL TX /SAMPLED BY 20Z FWD RAOB/...AND
SURFACE TEMPERATURES S/W OF THE BOUNDARY FROM 95-100 DEG F...LARGE
INSTABILITY WILL REMAIN FAVORABLE FOR ALL SEVERE HAZARDS WITH
ACTIVITY GRADUALLY SHIFTING S/SEWD.
FARTHER NW...INITIAL CONVECTIVE ATTEMPTS HAVE FAILED TO YIELD TSTMS
ALONG THE SLOWLY WWD-PROGRESSING OUTFLOW WHICH HAS ESSENTIALLY
OCCLUDED WITH THE REMNANT QUASI-STATIONARY FRONTAL ZONE. ALTHOUGH
TEMPERATURES ARE NOT QUITE AS WARM AS FARTHER S...REINFORCING
OUTFLOW FROM THE SUPERCELL CLUSTERS MAY YIELD SUSTAINABLE CONVECTIVE
DEVELOPMENT INTO THE WRN TX PANHANDLE.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34210044 33809969 33189959 32789978 32650017 32530071
32960149 33780214 34380237 35110256 35410245 35550224
35490202 35180199 34620190 34400163 34160095 34210044
000
ACUS11 KWNS 232033
SWOMCD
SPC MCD 232032
TXZ000-232200-
MESOSCALE DISCUSSION 0784
NWS STORM PREDICTION CENTER NORMAN OK
0332 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...TORNADO WATCH 213...
VALID 232032Z - 232200Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.
SUMMARY...GREATEST NEAR-TERM POTENTIAL FOR VERY LARGE HAIL...SEVERE
WINDS AND MESOCYCLONE TORNADOES SHOULD REMAIN WITH A SUPERCELL
CLUSTER IN THE ERN HALF OF THE LUB CWA. ADDITIONAL TSTMS MAY DEVELOP
BY 22Z ALONG THE OCCLUDED OUTFLOW/FRONT FARTHER NW IN THE WRN TX
PANHANDLE.
DISCUSSION...SUPERCELL OVER FLOYD COUNTY HAS PERSISTENTLY MOVED
SLOWLY SWD...WHILE ADDITIONAL UPDRAFTS HAVE FORMED SEWD ON THE COOL
SIDE OF THE INCREASINGLY DIFFUSE LARGER-SCALE OUTFLOW BOUNDARY. WITH
60S SURFACE DEW POINTS PERSISTING N/E OF THE OUTFLOW ACROSS THE LOW
ROLLING PLAINS INTO N-CNTRL TX /SAMPLED BY 20Z FWD RAOB/...AND
SURFACE TEMPERATURES S/W OF THE BOUNDARY FROM 95-100 DEG F...LARGE
INSTABILITY WILL REMAIN FAVORABLE FOR ALL SEVERE HAZARDS WITH
ACTIVITY GRADUALLY SHIFTING S/SEWD.
FARTHER NW...INITIAL CONVECTIVE ATTEMPTS HAVE FAILED TO YIELD TSTMS
ALONG THE SLOWLY WWD-PROGRESSING OUTFLOW WHICH HAS ESSENTIALLY
OCCLUDED WITH THE REMNANT QUASI-STATIONARY FRONTAL ZONE. ALTHOUGH
TEMPERATURES ARE NOT QUITE AS WARM AS FARTHER S...REINFORCING
OUTFLOW FROM THE SUPERCELL CLUSTERS MAY YIELD SUSTAINABLE CONVECTIVE
DEVELOPMENT INTO THE WRN TX PANHANDLE.
..GRAMS.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34210044 33809969 33189959 32789978 32650017 32530071
32960149 33780214 34380237 35110256 35410245 35550224
35490202 35180199 34620190 34400163 34160095 34210044
000
ACUS01 KWNS 231954
SWODY1
SPC AC 231951
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0251 PM CDT THU MAY 23 2013
VALID 232000Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF NWRN TX...
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM
WEST TX INTO THE NRN TX PANHANDLE...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID
ATLANTIC INTO THE NORTHEAST...
...SOUTHERN PLAINS...
HAVE MADE A FEW CHANGES TO 1630Z OUTLOOK ACROSS THE SRN PLAINS.
REMNANTS OF DECAYED MCS HAVE MIGRATED INTO THE ARKLATEX AND WEAK
CONVERGENCE ALONG THE CONVECTIVE OUTFLOW BOUNDARY EXTENDS ACROSS
NCNTRL TX WHERE TEMPERATURES HAVE WARMED INTO THE MID 80S. ALTHOUGH
SIGNIFICANT MOISTURE/INSTABILITY RESIDE ACROSS THIS REGION THERE IS
LESSENING CONFIDENCE LOW LEVEL CONVERGENCE WILL PROVE SUFFICIENT FOR
MORE THAN A FEW TSTMS LATER TODAY.
ANOTHER AREA WHERE PROBABILITIES HAVE BEEN ADJUSTED ARE ACROSS THE
BIG BEND REGION OF WEST TX. TSTMS HAVE RECENTLY DEVELOPED AND ARE
INTENSIFYING WITHIN MOIST SELY LOW LEVEL FLOW. WHILE DEEP LAYER
SHEAR IS NOT PARTICULARLY STRONG...FLOW APPEARS ADEQUATE TO WARRANT
AT LEAST SLOW MOVING ORGANIZED MULTI-CELLS CAPABLE OF PRODUCING
LARGE HAIL.
FARTHER NORTH ACROSS THE MDT RISK...WWD MOVING OUTFLOW IS SURGING
ACROSS THE PANHANDLE AND SHOULD STALL SOON. STRONG HEATING NEAR THE
WIND SHIFT AND FAVORABLE UPSLOPE FLOW WILL LIKELY CONTRIBUTE TO
SIGNIFICANT TSTM DEVELOPMENT OVER THE NEXT FEW HOURS. LATEST VIS
IMAGERY SUPPORTS THIS WITH TOWER CU NEAR/JUST WEST OF THE I-27
CORRIDOR. AFTER INITIAL SUPERCELL DEVELOPMENT ONE OR MORE MCS/S
SHOULD EVOLVE OVER THE SOUTH PLAINS WITH SUBSEQUENT PROPAGATION
EXPECTED INTO PORTIONS OF NWRN TX.
...MID ATLANTIC STATES INTO THE NORTHEAST...
ONLY MINOR CHANGES HAVE BEEN MADE TO EARLIER PROBABILITIES...NAMELY
TO EXTEND 2 PERCENT TORNADO PROBS SOUTHWARD ACROSS THE DELMARVA TO
ACCOUNT FOR WEAK SUPERCELL STRUCTURES OVER THIS REGION.
..DARROW.. 05/23/2013
.PREV DISCUSSION... /ISSUED 1120 AM CDT THU MAY 23 2013/
...SYNOPSIS...
WHILE THE CURRENT BLOCKING PATTERN OVER NORTH AMERICA IS EXPECTED TO
BECOME A BIT LESS PROMINENT...LARGE-SCALE MID/UPPER FLOW OVER THE
U.S. IS EXPECTED TO REMAIN AMPLIFIED AND SLOW TO CHANGE. IN THE
EAST...THE TRANSITION OF A CLOSED LOW TO AN OPEN WAVE TROUGH
CONTINUES ACROSS THE GREAT LAKES AND LOWER OHIO VALLEY REGION...TO
THE SOUTH OF A SHORT WAVE TROUGH SLOWLY DIGGING SOUTHEAST OF THE
HUDSON/JAMES BAY REGION. BOTH THESE FEATURES WILL CONTINUE TO
GRADUALLY TURN EASTWARD/SOUTHEASTWARD TOWARD THE ATLANTIC SEABOARD
LATER TODAY AND TONIGHT. AT THE SAME TIME...A DEEP MID-LEVEL CLOSED
LOW WILL LINGER OVER THE PACIFIC NORTHWEST...WITH BROADER SCALE
UPPER TROUGHING ENCOMPASSING MUCH OF THE PACIFIC COAST STATES INTO
THE ROCKIES. A SIGNIFICANT MID-LEVEL IMPULSE IS EXPECTED TO
CONTINUE TO GRADUALLY PIVOT AROUND THE LOW...ACROSS THE NORTHERN
GREAT BASIN INTO THE NORTHERN ROCKIES BY LATE TONIGHT. THIS WILL
SUPPRESS MID-LEVEL HEIGHT RISES ACROSS PARTS OF THE NORTHERN
PLAINS...WHILE MID/UPPER RIDGING REMAINS OR BECOME MORE PROMINENT
ACROSS MUCH OF THE PLAINS INTO THE MISSISSIPPI VALLEY REGION. A
COUPLE OF WEAK IMPULSES PROGRESSING THROUGH THE CYCLONIC FLOW ACROSS
THE SOUTHERN PLATEAU INTO THE SOUTHERN ROCKIES REGION MAY HAVE AT
LEAST A GLANCING IMPACT ON PARTS OF THE SOUTHERN PLAINS...HOWEVER.
...MID ATLANTIC STATES INTO THE NORTHEAST...
AHEAD/EAST OF A COLD FRONT ADVANCING ACROSS THE LOWER GREAT LAKES
AND OHIO VALLEY REGION...MID-LEVEL LAPSE RATES APPEAR TO HAVE
STABILIZED CONSIDERABLY OVER THE PAST COUPLE OF DAYS. CONSIDERABLE
CLOUD COVER AND PRECIPITATION...SOME CONVECTIVE...IS ALREADY WELL
UNDERWAY...AND IT IS NOT CLEAR HOW MUCH DESTABILIZATION WILL TAKE
PLACE TODAY. THERE ARE BREAKS IN CLOUD COVER...WHICH WILL ALLOW FOR
AT LEAST POCKETS OF HEATING AND WEAK TO MODEST DESTABILIZATION...THE
STRONGEST OF WHICH SEEMS LIKELY TO TAKE PLACE ALONG THE LEE SURFACE
TROUGH...EAST OF THE APPALACHIANS. THIS MAY INCLUDE THE URBAN
CORRIDOR FROM WASHINGTON D.C./BALTIMORE INTO THE PHILADELPHIA AREA.
WHERE SUBSTANTIVE DESTABILIZATION IS ABLE TO TAKE PLACE...SHEAR AND
MOMENTUM ASSOCIATED WITH 20-40 KT SOUTHWESTERLY LOWER/MID
TROPOSPHERIC FLOW MAY ENHANCE CONVECTIVE DEVELOPMENT... CONTRIBUTING
TO STORM MOTION AND ORGANIZATION. STRONGEST ACTIVITY MAY BE CAPABLE
OF PRODUCING SEVERE WIND GUSTS...WITH SOMEWHAT LOWER POTENTIAL FOR
SEVERE HAIL OR A TORNADO.
...SOUTHERN PLAINS...
THE SEVERE STORM/SMALL STORM CLUSTER THAT EVOLVED FROM A LARGER
SCALE WARM ADVECTION REGIME OVER CENTRAL OKLAHOMA EARLIER THIS
MORNING IS CURRENTLY WEAKENING SOUTH OF THE RED RIVER...ACROSS PARTS
OF NORTHEAST TEXAS. IT MAY NOT BE OUT OF THE QUESTION THAT REMNANTS
OF THIS ACTIVITY COULD BE ASSOCIATED WITH NEW INTENSE STORM
DEVELOPMENT ACROSS PARTS OF EASTERN TEXAS INTO LOUISIANA LATER
TODAY...IN THE PRESENCE OF POTENTIALLY STRONG INSTABILITY.
HOWEVER...THE PRIMARY CONVECTIVE POTENTIAL IS EXPECTED TO BECOME
FOCUSED NEAR THE DRYLINE AND A DEVELOPING WARM FRONT ACROSS THE
SOUTHERN HIGH PLAINS LATER THIS AFTERNOON AND EVENING.
DESPITE THE TENDENCY FOR CONTINUING WEAK MID-LEVEL HEIGHT RISES
ACROSS THE SOUTHERN PLAINS TODAY...MODELS SUGGEST CONVECTIVE
INHIBITION WILL WEAKEN SUFFICIENTLY BY PEAK AFTERNOON HEATING FOR
STORM INITIATION ON THE DRYLINE. THE MOST INTENSE STORMS/GREATEST
STORM COVERAGE IS EXPECTED NEAR THE DRYLINE/WARM FRONT
INTERSECTION...EAST/SOUTHEAST OF LUBBOCK AND AMARILLO INTO AREAS OF
NORTHWEST TEXAS NEAR/SOUTH OF CHILDRESS. THIS IS WHERE
THERMODYNAMIC PROFILES WITH VERY STEEP MID-LEVEL LAPSE RATES AND
LARGE CAPE SHOULD BE SUPPORTIVE OF SUPERCELLS...BEFORE CONSIDERABLE
UPSCALE GROWTH OCCURS BY EARLY EVENING.
VERY LARGE HAIL IS POSSIBLE IN STRONGEST CELLS. A COUPLE OF
TORNADOES ARE ALSO POSSIBLE...BUT TORNADIC POTENTIAL MAY BE HINDERED
BY WEAKNESS IN MID-LEVEL FLOW...AND A TENDENCY FOR STORMS TO QUICKLY
GENERATE CONSIDERABLE OUTFLOW.
...NORTHERN ROCKIES...
ALTHOUGH MOISTURE APPEARS TO REMAIN LIMITED ACROSS THE BASINS
WEST/SOUTH OF THE LARAMIE AND BIG HORN MOUNTAINS OF WYOMING... THE
ENVIRONMENT APPEARS AT LEAST MARGINALLY CONDUCIVE TO ISOLATED
SUPERCELL DEVELOPMENT LATE THIS AFTERNOON/EVENING...SOME OF WHICH
COULD DEVELOP/SPREAD NORTH/EAST OF THE MOUNTAINS INTO PARTS OF
EASTERN WYOMING AND MONTANA.
000
ACUS01 KWNS 231954
SWODY1
SPC AC 231951
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0251 PM CDT THU MAY 23 2013
VALID 232000Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF NWRN TX...
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM
WEST TX INTO THE NRN TX PANHANDLE...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID
ATLANTIC INTO THE NORTHEAST...
...SOUTHERN PLAINS...
HAVE MADE A FEW CHANGES TO 1630Z OUTLOOK ACROSS THE SRN PLAINS.
REMNANTS OF DECAYED MCS HAVE MIGRATED INTO THE ARKLATEX AND WEAK
CONVERGENCE ALONG THE CONVECTIVE OUTFLOW BOUNDARY EXTENDS ACROSS
NCNTRL TX WHERE TEMPERATURES HAVE WARMED INTO THE MID 80S. ALTHOUGH
SIGNIFICANT MOISTURE/INSTABILITY RESIDE ACROSS THIS REGION THERE IS
LESSENING CONFIDENCE LOW LEVEL CONVERGENCE WILL PROVE SUFFICIENT FOR
MORE THAN A FEW TSTMS LATER TODAY.
ANOTHER AREA WHERE PROBABILITIES HAVE BEEN ADJUSTED ARE ACROSS THE
BIG BEND REGION OF WEST TX. TSTMS HAVE RECENTLY DEVELOPED AND ARE
INTENSIFYING WITHIN MOIST SELY LOW LEVEL FLOW. WHILE DEEP LAYER
SHEAR IS NOT PARTICULARLY STRONG...FLOW APPEARS ADEQUATE TO WARRANT
AT LEAST SLOW MOVING ORGANIZED MULTI-CELLS CAPABLE OF PRODUCING
LARGE HAIL.
FARTHER NORTH ACROSS THE MDT RISK...WWD MOVING OUTFLOW IS SURGING
ACROSS THE PANHANDLE AND SHOULD STALL SOON. STRONG HEATING NEAR THE
WIND SHIFT AND FAVORABLE UPSLOPE FLOW WILL LIKELY CONTRIBUTE TO
SIGNIFICANT TSTM DEVELOPMENT OVER THE NEXT FEW HOURS. LATEST VIS
IMAGERY SUPPORTS THIS WITH TOWER CU NEAR/JUST WEST OF THE I-27
CORRIDOR. AFTER INITIAL SUPERCELL DEVELOPMENT ONE OR MORE MCS/S
SHOULD EVOLVE OVER THE SOUTH PLAINS WITH SUBSEQUENT PROPAGATION
EXPECTED INTO PORTIONS OF NWRN TX.
...MID ATLANTIC STATES INTO THE NORTHEAST...
ONLY MINOR CHANGES HAVE BEEN MADE TO EARLIER PROBABILITIES...NAMELY
TO EXTEND 2 PERCENT TORNADO PROBS SOUTHWARD ACROSS THE DELMARVA TO
ACCOUNT FOR WEAK SUPERCELL STRUCTURES OVER THIS REGION.
..DARROW.. 05/23/2013
.PREV DISCUSSION... /ISSUED 1120 AM CDT THU MAY 23 2013/
...SYNOPSIS...
WHILE THE CURRENT BLOCKING PATTERN OVER NORTH AMERICA IS EXPECTED TO
BECOME A BIT LESS PROMINENT...LARGE-SCALE MID/UPPER FLOW OVER THE
U.S. IS EXPECTED TO REMAIN AMPLIFIED AND SLOW TO CHANGE. IN THE
EAST...THE TRANSITION OF A CLOSED LOW TO AN OPEN WAVE TROUGH
CONTINUES ACROSS THE GREAT LAKES AND LOWER OHIO VALLEY REGION...TO
THE SOUTH OF A SHORT WAVE TROUGH SLOWLY DIGGING SOUTHEAST OF THE
HUDSON/JAMES BAY REGION. BOTH THESE FEATURES WILL CONTINUE TO
GRADUALLY TURN EASTWARD/SOUTHEASTWARD TOWARD THE ATLANTIC SEABOARD
LATER TODAY AND TONIGHT. AT THE SAME TIME...A DEEP MID-LEVEL CLOSED
LOW WILL LINGER OVER THE PACIFIC NORTHWEST...WITH BROADER SCALE
UPPER TROUGHING ENCOMPASSING MUCH OF THE PACIFIC COAST STATES INTO
THE ROCKIES. A SIGNIFICANT MID-LEVEL IMPULSE IS EXPECTED TO
CONTINUE TO GRADUALLY PIVOT AROUND THE LOW...ACROSS THE NORTHERN
GREAT BASIN INTO THE NORTHERN ROCKIES BY LATE TONIGHT. THIS WILL
SUPPRESS MID-LEVEL HEIGHT RISES ACROSS PARTS OF THE NORTHERN
PLAINS...WHILE MID/UPPER RIDGING REMAINS OR BECOME MORE PROMINENT
ACROSS MUCH OF THE PLAINS INTO THE MISSISSIPPI VALLEY REGION. A
COUPLE OF WEAK IMPULSES PROGRESSING THROUGH THE CYCLONIC FLOW ACROSS
THE SOUTHERN PLATEAU INTO THE SOUTHERN ROCKIES REGION MAY HAVE AT
LEAST A GLANCING IMPACT ON PARTS OF THE SOUTHERN PLAINS...HOWEVER.
...MID ATLANTIC STATES INTO THE NORTHEAST...
AHEAD/EAST OF A COLD FRONT ADVANCING ACROSS THE LOWER GREAT LAKES
AND OHIO VALLEY REGION...MID-LEVEL LAPSE RATES APPEAR TO HAVE
STABILIZED CONSIDERABLY OVER THE PAST COUPLE OF DAYS. CONSIDERABLE
CLOUD COVER AND PRECIPITATION...SOME CONVECTIVE...IS ALREADY WELL
UNDERWAY...AND IT IS NOT CLEAR HOW MUCH DESTABILIZATION WILL TAKE
PLACE TODAY. THERE ARE BREAKS IN CLOUD COVER...WHICH WILL ALLOW FOR
AT LEAST POCKETS OF HEATING AND WEAK TO MODEST DESTABILIZATION...THE
STRONGEST OF WHICH SEEMS LIKELY TO TAKE PLACE ALONG THE LEE SURFACE
TROUGH...EAST OF THE APPALACHIANS. THIS MAY INCLUDE THE URBAN
CORRIDOR FROM WASHINGTON D.C./BALTIMORE INTO THE PHILADELPHIA AREA.
WHERE SUBSTANTIVE DESTABILIZATION IS ABLE TO TAKE PLACE...SHEAR AND
MOMENTUM ASSOCIATED WITH 20-40 KT SOUTHWESTERLY LOWER/MID
TROPOSPHERIC FLOW MAY ENHANCE CONVECTIVE DEVELOPMENT... CONTRIBUTING
TO STORM MOTION AND ORGANIZATION. STRONGEST ACTIVITY MAY BE CAPABLE
OF PRODUCING SEVERE WIND GUSTS...WITH SOMEWHAT LOWER POTENTIAL FOR
SEVERE HAIL OR A TORNADO.
...SOUTHERN PLAINS...
THE SEVERE STORM/SMALL STORM CLUSTER THAT EVOLVED FROM A LARGER
SCALE WARM ADVECTION REGIME OVER CENTRAL OKLAHOMA EARLIER THIS
MORNING IS CURRENTLY WEAKENING SOUTH OF THE RED RIVER...ACROSS PARTS
OF NORTHEAST TEXAS. IT MAY NOT BE OUT OF THE QUESTION THAT REMNANTS
OF THIS ACTIVITY COULD BE ASSOCIATED WITH NEW INTENSE STORM
DEVELOPMENT ACROSS PARTS OF EASTERN TEXAS INTO LOUISIANA LATER
TODAY...IN THE PRESENCE OF POTENTIALLY STRONG INSTABILITY.
HOWEVER...THE PRIMARY CONVECTIVE POTENTIAL IS EXPECTED TO BECOME
FOCUSED NEAR THE DRYLINE AND A DEVELOPING WARM FRONT ACROSS THE
SOUTHERN HIGH PLAINS LATER THIS AFTERNOON AND EVENING.
DESPITE THE TENDENCY FOR CONTINUING WEAK MID-LEVEL HEIGHT RISES
ACROSS THE SOUTHERN PLAINS TODAY...MODELS SUGGEST CONVECTIVE
INHIBITION WILL WEAKEN SUFFICIENTLY BY PEAK AFTERNOON HEATING FOR
STORM INITIATION ON THE DRYLINE. THE MOST INTENSE STORMS/GREATEST
STORM COVERAGE IS EXPECTED NEAR THE DRYLINE/WARM FRONT
INTERSECTION...EAST/SOUTHEAST OF LUBBOCK AND AMARILLO INTO AREAS OF
NORTHWEST TEXAS NEAR/SOUTH OF CHILDRESS. THIS IS WHERE
THERMODYNAMIC PROFILES WITH VERY STEEP MID-LEVEL LAPSE RATES AND
LARGE CAPE SHOULD BE SUPPORTIVE OF SUPERCELLS...BEFORE CONSIDERABLE
UPSCALE GROWTH OCCURS BY EARLY EVENING.
VERY LARGE HAIL IS POSSIBLE IN STRONGEST CELLS. A COUPLE OF
TORNADOES ARE ALSO POSSIBLE...BUT TORNADIC POTENTIAL MAY BE HINDERED
BY WEAKNESS IN MID-LEVEL FLOW...AND A TENDENCY FOR STORMS TO QUICKLY
GENERATE CONSIDERABLE OUTFLOW.
...NORTHERN ROCKIES...
ALTHOUGH MOISTURE APPEARS TO REMAIN LIMITED ACROSS THE BASINS
WEST/SOUTH OF THE LARAMIE AND BIG HORN MOUNTAINS OF WYOMING... THE
ENVIRONMENT APPEARS AT LEAST MARGINALLY CONDUCIVE TO ISOLATED
SUPERCELL DEVELOPMENT LATE THIS AFTERNOON/EVENING...SOME OF WHICH
COULD DEVELOP/SPREAD NORTH/EAST OF THE MOUNTAINS INTO PARTS OF
EASTERN WYOMING AND MONTANA.
000
ACUS11 KWNS 231938
SWOMCD
SPC MCD 231937
PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-WVZ000-232030-
MESOSCALE DISCUSSION 0783
NWS STORM PREDICTION CENTER NORMAN OK
0237 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF CENTRAL VA...MD...SRN PA...NRN DE
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231937Z - 232030Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCTD SVR TSTMS WITH AT LEAST SOME THREAT FOR DAMAGING
WINDS...MARGINALLY SVR HAIL AND A BRIEF TORNADO WILL CONTINUE
THROUGH 23Z. TRENDS ARE BEING MONITORED FOR A POSSIBLE WW.
DISCUSSION...SCTD STG/SVR TSTMS HAVE DEVELOPED ALONG THE BLUE RIDGE
MTNS THIS AFTN WHERE BREAKS IN CLOUD COVER HAS ALLOWED TEMPERATURES
TO CLIMB TO NEAR 80 WITH DEW POINTS IN THE MID TO UPPER 60S. MLCAPE
VALUES AVERAGE AROUND 1000 J/KG...LOCALLY HIGHER WHERE MORE
PERSISTENT BREAKS IN THE CLOUDS EXIST. MESOANALYSIS AND AREA VWP
DATA SHOW MODEST 0-6 KM SHEAR AVERAGING 30 KTS...SUPPORTIVE OF
ORGANIZED TSTMS. PW VALUES APPROACHING 1.5 INCHES WILL SUPPORT THE
POTENTIAL FOR DAMAGING DOWNBURST WINDS WITH THE STRONGEST TSTMS. AN
ISOLD LARGE HAIL REPORT IS ALSO POSSIBLE. A BRIEF TORNADO CANNOT BE
RULED OUT IN THE LEE OF THE BLUE RIDGE OVER NRN VA WHERE SURFACE
PRESSURE FALLS WERE NOTED IN ASSOCIATION WITH A WEAK SURFACE LOW.
THE THREAT SHOULD DIMINISH AFT 23Z AS DIURNAL COOLING COMMENCES.
..BUNTING/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...AKQ...CTP...LWX...RNK...
LAT...LON 39657821 40477767 40657689 40457591 40047559 39467575
38037661 36627785 36597860 36797934 37527955 39657821
000
ACUS11 KWNS 231938
SWOMCD
SPC MCD 231937
PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-WVZ000-232030-
MESOSCALE DISCUSSION 0783
NWS STORM PREDICTION CENTER NORMAN OK
0237 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF CENTRAL VA...MD...SRN PA...NRN DE
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231937Z - 232030Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCTD SVR TSTMS WITH AT LEAST SOME THREAT FOR DAMAGING
WINDS...MARGINALLY SVR HAIL AND A BRIEF TORNADO WILL CONTINUE
THROUGH 23Z. TRENDS ARE BEING MONITORED FOR A POSSIBLE WW.
DISCUSSION...SCTD STG/SVR TSTMS HAVE DEVELOPED ALONG THE BLUE RIDGE
MTNS THIS AFTN WHERE BREAKS IN CLOUD COVER HAS ALLOWED TEMPERATURES
TO CLIMB TO NEAR 80 WITH DEW POINTS IN THE MID TO UPPER 60S. MLCAPE
VALUES AVERAGE AROUND 1000 J/KG...LOCALLY HIGHER WHERE MORE
PERSISTENT BREAKS IN THE CLOUDS EXIST. MESOANALYSIS AND AREA VWP
DATA SHOW MODEST 0-6 KM SHEAR AVERAGING 30 KTS...SUPPORTIVE OF
ORGANIZED TSTMS. PW VALUES APPROACHING 1.5 INCHES WILL SUPPORT THE
POTENTIAL FOR DAMAGING DOWNBURST WINDS WITH THE STRONGEST TSTMS. AN
ISOLD LARGE HAIL REPORT IS ALSO POSSIBLE. A BRIEF TORNADO CANNOT BE
RULED OUT IN THE LEE OF THE BLUE RIDGE OVER NRN VA WHERE SURFACE
PRESSURE FALLS WERE NOTED IN ASSOCIATION WITH A WEAK SURFACE LOW.
THE THREAT SHOULD DIMINISH AFT 23Z AS DIURNAL COOLING COMMENCES.
..BUNTING/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...AKQ...CTP...LWX...RNK...
LAT...LON 39657821 40477767 40657689 40457591 40047559 39467575
38037661 36627785 36597860 36797934 37527955 39657821
000
ACUS11 KWNS 231938
SWOMCD
SPC MCD 231937
PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-WVZ000-232030-
MESOSCALE DISCUSSION 0783
NWS STORM PREDICTION CENTER NORMAN OK
0237 PM CDT THU MAY 23 2013
AREAS AFFECTED...PORTIONS OF CENTRAL VA...MD...SRN PA...NRN DE
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231937Z - 232030Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCTD SVR TSTMS WITH AT LEAST SOME THREAT FOR DAMAGING
WINDS...MARGINALLY SVR HAIL AND A BRIEF TORNADO WILL CONTINUE
THROUGH 23Z. TRENDS ARE BEING MONITORED FOR A POSSIBLE WW.
DISCUSSION...SCTD STG/SVR TSTMS HAVE DEVELOPED ALONG THE BLUE RIDGE
MTNS THIS AFTN WHERE BREAKS IN CLOUD COVER HAS ALLOWED TEMPERATURES
TO CLIMB TO NEAR 80 WITH DEW POINTS IN THE MID TO UPPER 60S. MLCAPE
VALUES AVERAGE AROUND 1000 J/KG...LOCALLY HIGHER WHERE MORE
PERSISTENT BREAKS IN THE CLOUDS EXIST. MESOANALYSIS AND AREA VWP
DATA SHOW MODEST 0-6 KM SHEAR AVERAGING 30 KTS...SUPPORTIVE OF
ORGANIZED TSTMS. PW VALUES APPROACHING 1.5 INCHES WILL SUPPORT THE
POTENTIAL FOR DAMAGING DOWNBURST WINDS WITH THE STRONGEST TSTMS. AN
ISOLD LARGE HAIL REPORT IS ALSO POSSIBLE. A BRIEF TORNADO CANNOT BE
RULED OUT IN THE LEE OF THE BLUE RIDGE OVER NRN VA WHERE SURFACE
PRESSURE FALLS WERE NOTED IN ASSOCIATION WITH A WEAK SURFACE LOW.
THE THREAT SHOULD DIMINISH AFT 23Z AS DIURNAL COOLING COMMENCES.
..BUNTING/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...AKQ...CTP...LWX...RNK...
LAT...LON 39657821 40477767 40657689 40457591 40047559 39467575
38037661 36627785 36597860 36797934 37527955 39657821
000
ACUS11 KWNS 231805
SWOMCD
SPC MCD 231804
TXZ000-232000-
MESOSCALE DISCUSSION 0782
NWS STORM PREDICTION CENTER NORMAN OK
0104 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 231804Z - 232000Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTM INITIATION MAY OCCUR AS EARLY AS 19-20Z ALONG A
WWD-MOVING OUTFLOW BOUNDARY AND WEAK SURFACE CYCLONE NEAR AMA. VERY
STEEP LAPSE RATES...LARGE BUOYANCY AND SUFFICIENT DEEP-LAYER SHEAR
WILL EXIST FOR SUPERCELLS PRIMARILY PRODUCING VERY LARGE
HAIL...ALONG WITH A FEW TORNADOES AND ISOLATED SEVERE WINDS.
DISCUSSION...OUTFLOW BOUNDARY FROM DECAYING MCS ALONG THE RED RIVER
IN SERN OK/NERN TX CONTINUES TO MOVE WWD TO NEAR AMA SEWD ACROSS THE
LOW ROLLING PLAINS OF NWRN TX. SURFACE TEMPERATURES HAVE REACHED THE
LOWER 90S SW OF THIS BOUNDARY. MODIFIED 12Z MAF RAOBS AND RECENT
ACARS DATA INVOF LBB SUGGEST INHIBITION WILL BECOME MINIMAL SOON.
WITH PERSISTENT CONVERGENCE ALONG THE BOUNDARY...CONVECTION-ALLOWING
MODEL GUIDANCE INDICATE INITIAL TSTM DEVELOPMENT WILL OCCUR BETWEEN
19-21Z.
ALTHOUGH MIXING WILL CONTINUE ALONG THE NWRN PERIPHERY OF THE RICH
GULF MOISTURE PLUME...RESULTING IN LOWERING SURFACE DEW
POINTS...VERY STEEP LAPSE RATES AND MLCAPE AOA 2500 J/KG WILL
PROMOTE RAPID SUPERCELL DEVELOPMENT ONCE INITIATION OCCURS. LARGE TO
GIANT HAIL IS QUITE LIKELY WHERE THIS OCCURS. TORNADO POTENTIAL
SHOULD BE MAXIMIZED ALONG AND NEAR THE COOL SIDE OF THE OUTFLOW
BOUNDARY WHERE LOW-LEVEL SRH WILL BE ENHANCED AND LCL HEIGHTS WILL
BE LOWER.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34460191 35340196 35520183 35550151 35420117 34630020
33879952 33449946 33009969 32780023 32790116 33360195
34460191
000
ACUS11 KWNS 231805
SWOMCD
SPC MCD 231804
TXZ000-232000-
MESOSCALE DISCUSSION 0782
NWS STORM PREDICTION CENTER NORMAN OK
0104 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 231804Z - 232000Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTM INITIATION MAY OCCUR AS EARLY AS 19-20Z ALONG A
WWD-MOVING OUTFLOW BOUNDARY AND WEAK SURFACE CYCLONE NEAR AMA. VERY
STEEP LAPSE RATES...LARGE BUOYANCY AND SUFFICIENT DEEP-LAYER SHEAR
WILL EXIST FOR SUPERCELLS PRIMARILY PRODUCING VERY LARGE
HAIL...ALONG WITH A FEW TORNADOES AND ISOLATED SEVERE WINDS.
DISCUSSION...OUTFLOW BOUNDARY FROM DECAYING MCS ALONG THE RED RIVER
IN SERN OK/NERN TX CONTINUES TO MOVE WWD TO NEAR AMA SEWD ACROSS THE
LOW ROLLING PLAINS OF NWRN TX. SURFACE TEMPERATURES HAVE REACHED THE
LOWER 90S SW OF THIS BOUNDARY. MODIFIED 12Z MAF RAOBS AND RECENT
ACARS DATA INVOF LBB SUGGEST INHIBITION WILL BECOME MINIMAL SOON.
WITH PERSISTENT CONVERGENCE ALONG THE BOUNDARY...CONVECTION-ALLOWING
MODEL GUIDANCE INDICATE INITIAL TSTM DEVELOPMENT WILL OCCUR BETWEEN
19-21Z.
ALTHOUGH MIXING WILL CONTINUE ALONG THE NWRN PERIPHERY OF THE RICH
GULF MOISTURE PLUME...RESULTING IN LOWERING SURFACE DEW
POINTS...VERY STEEP LAPSE RATES AND MLCAPE AOA 2500 J/KG WILL
PROMOTE RAPID SUPERCELL DEVELOPMENT ONCE INITIATION OCCURS. LARGE TO
GIANT HAIL IS QUITE LIKELY WHERE THIS OCCURS. TORNADO POTENTIAL
SHOULD BE MAXIMIZED ALONG AND NEAR THE COOL SIDE OF THE OUTFLOW
BOUNDARY WHERE LOW-LEVEL SRH WILL BE ENHANCED AND LCL HEIGHTS WILL
BE LOWER.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34460191 35340196 35520183 35550151 35420117 34630020
33879952 33449946 33009969 32780023 32790116 33360195
34460191
000
ACUS11 KWNS 231805
SWOMCD
SPC MCD 231804
TXZ000-232000-
MESOSCALE DISCUSSION 0782
NWS STORM PREDICTION CENTER NORMAN OK
0104 PM CDT THU MAY 23 2013
AREAS AFFECTED...PANHANDLE/NWRN TX
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 231804Z - 232000Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTM INITIATION MAY OCCUR AS EARLY AS 19-20Z ALONG A
WWD-MOVING OUTFLOW BOUNDARY AND WEAK SURFACE CYCLONE NEAR AMA. VERY
STEEP LAPSE RATES...LARGE BUOYANCY AND SUFFICIENT DEEP-LAYER SHEAR
WILL EXIST FOR SUPERCELLS PRIMARILY PRODUCING VERY LARGE
HAIL...ALONG WITH A FEW TORNADOES AND ISOLATED SEVERE WINDS.
DISCUSSION...OUTFLOW BOUNDARY FROM DECAYING MCS ALONG THE RED RIVER
IN SERN OK/NERN TX CONTINUES TO MOVE WWD TO NEAR AMA SEWD ACROSS THE
LOW ROLLING PLAINS OF NWRN TX. SURFACE TEMPERATURES HAVE REACHED THE
LOWER 90S SW OF THIS BOUNDARY. MODIFIED 12Z MAF RAOBS AND RECENT
ACARS DATA INVOF LBB SUGGEST INHIBITION WILL BECOME MINIMAL SOON.
WITH PERSISTENT CONVERGENCE ALONG THE BOUNDARY...CONVECTION-ALLOWING
MODEL GUIDANCE INDICATE INITIAL TSTM DEVELOPMENT WILL OCCUR BETWEEN
19-21Z.
ALTHOUGH MIXING WILL CONTINUE ALONG THE NWRN PERIPHERY OF THE RICH
GULF MOISTURE PLUME...RESULTING IN LOWERING SURFACE DEW
POINTS...VERY STEEP LAPSE RATES AND MLCAPE AOA 2500 J/KG WILL
PROMOTE RAPID SUPERCELL DEVELOPMENT ONCE INITIATION OCCURS. LARGE TO
GIANT HAIL IS QUITE LIKELY WHERE THIS OCCURS. TORNADO POTENTIAL
SHOULD BE MAXIMIZED ALONG AND NEAR THE COOL SIDE OF THE OUTFLOW
BOUNDARY WHERE LOW-LEVEL SRH WILL BE ENHANCED AND LCL HEIGHTS WILL
BE LOWER.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 34460191 35340196 35520183 35550151 35420117 34630020
33879952 33449946 33009969 32780023 32790116 33360195
34460191
000
ACUS11 KWNS 231723
SWOMCD
SPC MCD 231722
TXZ000-NMZ000-231945-
MESOSCALE DISCUSSION 0781
NWS STORM PREDICTION CENTER NORMAN OK
1222 PM CDT THU MAY 23 2013
AREAS AFFECTED...TRANS-PECOS OF W TX
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 231722Z - 231945Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...SCATTERED TSTMS WILL DEVELOP OVER THE HIGH TERRAIN OF FAR
W TX THIS AFTERNOON. MODEST DEEP-LAYER SHEAR SHOULD DETER OVERALL
ORGANIZATION...BUT ISOLATED LARGE HAIL AND SEVERE WIND GUSTS ARE
POSSIBLE.
DISCUSSION...INITIAL CONVECTIVE TOWER HAS FORMED ALONG THE
JUXTAPOSITION OF JEFF DAVIS/REEVES/CULBERSON COUNTIES. MODEST
LOW-LEVEL UPSLOPE FLOW AMIDST CONTINUED ROBUST HEATING ALONG THE WRN
PERIPHERY OF A RICH GULF MOISTURE PLUME WILL PROMOTE ADDITIONAL
DEVELOPMENT THROUGH THE AFTERNOON. THIS SCENARIO IS WELL-SUPPORTED
BY MORNING CONVECTION-ALLOWING MODEL GUIDANCE. LOW/MID-LEVEL WINDS
ARE WEAK...BUT DIRECTIONAL VEERING OF THE PROFILE WITH HEIGHT ALONG
WITH MODERATE UPPER-LEVEL WLYS COULD YIELD MULTICELL/MARGINAL
SUPERCELL STRUCTURES. GIVEN STEEP LOW/MID-LEVEL LAPSE RATES...LARGE
HAIL WILL BE THE PRIMARY THREAT...WITH A RISK FOR MICROBURSTS AS
WELL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SJT...MAF...
LAT...LON 32090318 31660218 29910176 28900312 29700463 31930372
32090318
000
ACUS11 KWNS 231723
SWOMCD
SPC MCD 231722
TXZ000-NMZ000-231945-
MESOSCALE DISCUSSION 0781
NWS STORM PREDICTION CENTER NORMAN OK
1222 PM CDT THU MAY 23 2013
AREAS AFFECTED...TRANS-PECOS OF W TX
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 231722Z - 231945Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...SCATTERED TSTMS WILL DEVELOP OVER THE HIGH TERRAIN OF FAR
W TX THIS AFTERNOON. MODEST DEEP-LAYER SHEAR SHOULD DETER OVERALL
ORGANIZATION...BUT ISOLATED LARGE HAIL AND SEVERE WIND GUSTS ARE
POSSIBLE.
DISCUSSION...INITIAL CONVECTIVE TOWER HAS FORMED ALONG THE
JUXTAPOSITION OF JEFF DAVIS/REEVES/CULBERSON COUNTIES. MODEST
LOW-LEVEL UPSLOPE FLOW AMIDST CONTINUED ROBUST HEATING ALONG THE WRN
PERIPHERY OF A RICH GULF MOISTURE PLUME WILL PROMOTE ADDITIONAL
DEVELOPMENT THROUGH THE AFTERNOON. THIS SCENARIO IS WELL-SUPPORTED
BY MORNING CONVECTION-ALLOWING MODEL GUIDANCE. LOW/MID-LEVEL WINDS
ARE WEAK...BUT DIRECTIONAL VEERING OF THE PROFILE WITH HEIGHT ALONG
WITH MODERATE UPPER-LEVEL WLYS COULD YIELD MULTICELL/MARGINAL
SUPERCELL STRUCTURES. GIVEN STEEP LOW/MID-LEVEL LAPSE RATES...LARGE
HAIL WILL BE THE PRIMARY THREAT...WITH A RISK FOR MICROBURSTS AS
WELL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SJT...MAF...
LAT...LON 32090318 31660218 29910176 28900312 29700463 31930372
32090318
000
ACUS11 KWNS 231723
SWOMCD
SPC MCD 231722
TXZ000-NMZ000-231945-
MESOSCALE DISCUSSION 0781
NWS STORM PREDICTION CENTER NORMAN OK
1222 PM CDT THU MAY 23 2013
AREAS AFFECTED...TRANS-PECOS OF W TX
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 231722Z - 231945Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...SCATTERED TSTMS WILL DEVELOP OVER THE HIGH TERRAIN OF FAR
W TX THIS AFTERNOON. MODEST DEEP-LAYER SHEAR SHOULD DETER OVERALL
ORGANIZATION...BUT ISOLATED LARGE HAIL AND SEVERE WIND GUSTS ARE
POSSIBLE.
DISCUSSION...INITIAL CONVECTIVE TOWER HAS FORMED ALONG THE
JUXTAPOSITION OF JEFF DAVIS/REEVES/CULBERSON COUNTIES. MODEST
LOW-LEVEL UPSLOPE FLOW AMIDST CONTINUED ROBUST HEATING ALONG THE WRN
PERIPHERY OF A RICH GULF MOISTURE PLUME WILL PROMOTE ADDITIONAL
DEVELOPMENT THROUGH THE AFTERNOON. THIS SCENARIO IS WELL-SUPPORTED
BY MORNING CONVECTION-ALLOWING MODEL GUIDANCE. LOW/MID-LEVEL WINDS
ARE WEAK...BUT DIRECTIONAL VEERING OF THE PROFILE WITH HEIGHT ALONG
WITH MODERATE UPPER-LEVEL WLYS COULD YIELD MULTICELL/MARGINAL
SUPERCELL STRUCTURES. GIVEN STEEP LOW/MID-LEVEL LAPSE RATES...LARGE
HAIL WILL BE THE PRIMARY THREAT...WITH A RISK FOR MICROBURSTS AS
WELL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SJT...MAF...
LAT...LON 32090318 31660218 29910176 28900312 29700463 31930372
32090318
000
ACUS02 KWNS 231654
SWODY2
SPC AC 231652
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1152 AM CDT THU MAY 23 2013
VALID 241200Z - 251200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL HIGH PLAINS...
...CENTRAL/SOUTHERN PLAINS...
MEAN UPPER RIDGE WILL REMAIN ANCHORED OVER THE MIDDLE OF THE CONUS
THROUGH THE DAY2 PERIOD. WHILE EMBEDDED SHORT-WAVES WILL ROTATE
INTO THE BASE OF THE WRN U.S. TROUGH AND EJECT NEWD...IT APPEARS THE
PRIMARY INFLUENCE OF THESE FEATURES WILL BE NOTED ACROSS THE GREAT
BASIN INTO THE NRN ROCKIES...WELL WEST OF THE HIGH PLAINS. EVEN
SO...FAVORABLE LEE TROUGHING SHOULD ENCOURAGE A MOISTENING BOUNDARY
LAYER ACROSS THE HIGH PLAINS AND SFC DEW POINTS IN THE 50S SHOULD
EASILY BE TRANSPORTED ACROSS WRN KS INTO THE NEB PANHANDLE.
STRONG BOUNDARY LAYER HEATING IS ANTICIPATED ACROSS SERN WY/ERN CO
FRIDAY AFTERNOON AND THIS WILL PROVE INSTRUMENTAL IN CONVECTIVE
DEVELOPMENT NEAR/JUST EAST OF PALMER DIVIDE SFC LOW THAT IS EXPECTED
TO MIGRATE INTO NERN CO DURING THE EVENING. FAVORABLE UPSLOPE FLOW
AND SFC HEATING SHOULD PROVE ADEQUATE IN AT LEAST ISOLATED
SUPERCELLS BENEATH MODEST SWLY FLOW ALOFT...ON THE ORDER OF 35KT AT
500MB. LARGE HAIL IS EXPECTED WITH THESE STORMS AND IF DEW POINTS
CAN RISE INTO THE UPPER 50S CLOUD BASES SHOULD BE ADEQUATELY LOW AND
SUPPORTIVE OF TORNADOES.
FARTHER SOUTH...MUCH WEAKER FLOW IS EXPECTED ACROSS THE SRN PLAINS
WHERE SFC-6KM DEEP LAYER SHEAR SHOULD BE ON THE ORDER OF 15KT. IT/S
NOT ENTIRELY CLEAR HOW CONVECTION WILL EVOLVE ACROSS THIS REGION BUT
SFC HEATING BENEATH MID LEVEL WEAKNESS/COOLER MID LEVEL TEMPERATURES
FAVOR A FEW STRONG STORMS...ESPECIALLY GIVEN THE HIGHER DEW
POINTS/INSTABILITY. HAIL IS THE PRIMARY THREAT WITH THE MORE ROBUST
ACTIVITY.
...ELSEWHERE...
A FEW TSTMS MAY DEVELOP ACROSS THE CNTRL/SRN PENINSULA DURING THE
HEAT OF THE DAY AND ALONG NW-SE ORIENTED CONFLUENCE ZONE ACROSS SERN
TX INTO SRN LA. CONVECTION ACROSS BOTH REGIONS SHOULD EVOLVE WITHIN
AN ENVIRONMENT SUPPORTIVE OF GUSTY WINDS OR SMALL HAIL BUT LITTLE
CHANCE FOR MEANINGFUL ORGANIZATION.
..DARROW.. 05/23/2013
000
ACUS02 KWNS 231654
SWODY2
SPC AC 231652
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1152 AM CDT THU MAY 23 2013
VALID 241200Z - 251200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL HIGH PLAINS...
...CENTRAL/SOUTHERN PLAINS...
MEAN UPPER RIDGE WILL REMAIN ANCHORED OVER THE MIDDLE OF THE CONUS
THROUGH THE DAY2 PERIOD. WHILE EMBEDDED SHORT-WAVES WILL ROTATE
INTO THE BASE OF THE WRN U.S. TROUGH AND EJECT NEWD...IT APPEARS THE
PRIMARY INFLUENCE OF THESE FEATURES WILL BE NOTED ACROSS THE GREAT
BASIN INTO THE NRN ROCKIES...WELL WEST OF THE HIGH PLAINS. EVEN
SO...FAVORABLE LEE TROUGHING SHOULD ENCOURAGE A MOISTENING BOUNDARY
LAYER ACROSS THE HIGH PLAINS AND SFC DEW POINTS IN THE 50S SHOULD
EASILY BE TRANSPORTED ACROSS WRN KS INTO THE NEB PANHANDLE.
STRONG BOUNDARY LAYER HEATING IS ANTICIPATED ACROSS SERN WY/ERN CO
FRIDAY AFTERNOON AND THIS WILL PROVE INSTRUMENTAL IN CONVECTIVE
DEVELOPMENT NEAR/JUST EAST OF PALMER DIVIDE SFC LOW THAT IS EXPECTED
TO MIGRATE INTO NERN CO DURING THE EVENING. FAVORABLE UPSLOPE FLOW
AND SFC HEATING SHOULD PROVE ADEQUATE IN AT LEAST ISOLATED
SUPERCELLS BENEATH MODEST SWLY FLOW ALOFT...ON THE ORDER OF 35KT AT
500MB. LARGE HAIL IS EXPECTED WITH THESE STORMS AND IF DEW POINTS
CAN RISE INTO THE UPPER 50S CLOUD BASES SHOULD BE ADEQUATELY LOW AND
SUPPORTIVE OF TORNADOES.
FARTHER SOUTH...MUCH WEAKER FLOW IS EXPECTED ACROSS THE SRN PLAINS
WHERE SFC-6KM DEEP LAYER SHEAR SHOULD BE ON THE ORDER OF 15KT. IT/S
NOT ENTIRELY CLEAR HOW CONVECTION WILL EVOLVE ACROSS THIS REGION BUT
SFC HEATING BENEATH MID LEVEL WEAKNESS/COOLER MID LEVEL TEMPERATURES
FAVOR A FEW STRONG STORMS...ESPECIALLY GIVEN THE HIGHER DEW
POINTS/INSTABILITY. HAIL IS THE PRIMARY THREAT WITH THE MORE ROBUST
ACTIVITY.
...ELSEWHERE...
A FEW TSTMS MAY DEVELOP ACROSS THE CNTRL/SRN PENINSULA DURING THE
HEAT OF THE DAY AND ALONG NW-SE ORIENTED CONFLUENCE ZONE ACROSS SERN
TX INTO SRN LA. CONVECTION ACROSS BOTH REGIONS SHOULD EVOLVE WITHIN
AN ENVIRONMENT SUPPORTIVE OF GUSTY WINDS OR SMALL HAIL BUT LITTLE
CHANCE FOR MEANINGFUL ORGANIZATION.
..DARROW.. 05/23/2013
000
ACUS01 KWNS 231622
SWODY1
SPC AC 231620
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1120 AM CDT THU MAY 23 2013
VALID 231630Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS LATE THIS AFTN AND EVE ACROSS
PARTS OF THE EASTERN TEXAS PANHANDLE AND NORTHWEST TEXAS...
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
AREA ACROSS THE SOUTHERN PLAINS AND RED RIVER VALLEY REGION...
...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE MID
ATLANTIC STATES INTO NEW ENGLAND...
...SYNOPSIS...
WHILE THE CURRENT BLOCKING PATTERN OVER NORTH AMERICA IS EXPECTED TO
BECOME A BIT LESS PROMINENT...LARGE-SCALE MID/UPPER FLOW OVER THE
U.S. IS EXPECTED TO REMAIN AMPLIFIED AND SLOW TO CHANGE. IN THE
EAST...THE TRANSITION OF A CLOSED LOW TO AN OPEN WAVE TROUGH
CONTINUES ACROSS THE GREAT LAKES AND LOWER OHIO VALLEY REGION...TO
THE SOUTH OF A SHORT WAVE TROUGH SLOWLY DIGGING SOUTHEAST OF THE
HUDSON/JAMES BAY REGION. BOTH THESE FEATURES WILL CONTINUE TO
GRADUALLY TURN EASTWARD/SOUTHEASTWARD TOWARD THE ATLANTIC SEABOARD
LATER TODAY AND TONIGHT. AT THE SAME TIME...A DEEP MID-LEVEL CLOSED
LOW WILL LINGER OVER THE PACIFIC NORTHWEST...WITH BROADER SCALE
UPPER TROUGHING ENCOMPASSING MUCH OF THE PACIFIC COAST STATES INTO
THE ROCKIES. A SIGNIFICANT MID-LEVEL IMPULSE IS EXPECTED TO
CONTINUE TO GRADUALLY PIVOT AROUND THE LOW...ACROSS THE NORTHERN
GREAT BASIN INTO THE NORTHERN ROCKIES BY LATE TONIGHT. THIS WILL
SUPPRESS MID-LEVEL HEIGHT RISES ACROSS PARTS OF THE NORTHERN
PLAINS...WHILE MID/UPPER RIDGING REMAINS OR BECOME MORE PROMINENT
ACROSS MUCH OF THE PLAINS INTO THE MISSISSIPPI VALLEY REGION. A
COUPLE OF WEAK IMPULSES PROGRESSING THROUGH THE CYCLONIC FLOW ACROSS
THE SOUTHERN PLATEAU INTO THE SOUTHERN ROCKIES REGION MAY HAVE AT
LEAST A GLANCING IMPACT ON PARTS OF THE SOUTHERN PLAINS...HOWEVER.
...MID ATLANTIC STATES INTO THE NORTHEAST...
AHEAD/EAST OF A COLD FRONT ADVANCING ACROSS THE LOWER GREAT LAKES
AND OHIO VALLEY REGION...MID-LEVEL LAPSE RATES APPEAR TO HAVE
STABILIZED CONSIDERABLY OVER THE PAST COUPLE OF DAYS. CONSIDERABLE
CLOUD COVER AND PRECIPITATION...SOME CONVECTIVE...IS ALREADY WELL
UNDERWAY...AND IT IS NOT CLEAR HOW MUCH DESTABILIZATION WILL TAKE
PLACE TODAY. THERE ARE BREAKS IN CLOUD COVER...WHICH WILL ALLOW FOR
AT LEAST POCKETS OF HEATING AND WEAK TO MODEST DESTABILIZATION...THE
STRONGEST OF WHICH SEEMS LIKELY TO TAKE PLACE ALONG THE LEE SURFACE
TROUGH...EAST OF THE APPALACHIANS. THIS MAY INCLUDE THE URBAN
CORRIDOR FROM WASHINGTON D.C./BALTIMORE INTO THE PHILADELPHIA AREA.
WHERE SUBSTANTIVE DESTABILIZATION IS ABLE TO TAKE PLACE...SHEAR AND
MOMENTUM ASSOCIATED WITH 20-40 KT SOUTHWESTERLY LOWER/MID
TROPOSPHERIC FLOW MAY ENHANCE CONVECTIVE DEVELOPMENT... CONTRIBUTING
TO STORM MOTION AND ORGANIZATION. STRONGEST ACTIVITY MAY BE CAPABLE
OF PRODUCING SEVERE WIND GUSTS...WITH SOMEWHAT LOWER POTENTIAL FOR
SEVERE HAIL OR A TORNADO.
...SOUTHERN PLAINS...
THE SEVERE STORM/SMALL STORM CLUSTER THAT EVOLVED FROM A LARGER
SCALE WARM ADVECTION REGIME OVER CENTRAL OKLAHOMA EARLIER THIS
MORNING IS CURRENTLY WEAKENING SOUTH OF THE RED RIVER...ACROSS PARTS
OF NORTHEAST TEXAS. IT MAY NOT BE OUT OF THE QUESTION THAT REMNANTS
OF THIS ACTIVITY COULD BE ASSOCIATED WITH NEW INTENSE STORM
DEVELOPMENT ACROSS PARTS OF EASTERN TEXAS INTO LOUISIANA LATER
TODAY...IN THE PRESENCE OF POTENTIALLY STRONG INSTABILITY.
HOWEVER...THE PRIMARY CONVECTIVE POTENTIAL IS EXPECTED TO BECOME
FOCUSED NEAR THE DRYLINE AND A DEVELOPING WARM FRONT ACROSS THE
SOUTHERN HIGH PLAINS LATER THIS AFTERNOON AND EVENING.
DESPITE THE TENDENCY FOR CONTINUING WEAK MID-LEVEL HEIGHT RISES
ACROSS THE SOUTHERN PLAINS TODAY...MODELS SUGGEST CONVECTIVE
INHIBITION WILL WEAKEN SUFFICIENTLY BY PEAK AFTERNOON HEATING FOR
STORM INITIATION ON THE DRYLINE. THE MOST INTENSE STORMS/GREATEST
STORM COVERAGE IS EXPECTED NEAR THE DRYLINE/WARM FRONT
INTERSECTION...EAST/SOUTHEAST OF LUBBOCK AND AMARILLO INTO AREAS OF
NORTHWEST TEXAS NEAR/SOUTH OF CHILDRESS. THIS IS WHERE
THERMODYNAMIC PROFILES WITH VERY STEEP MID-LEVEL LAPSE RATES AND
LARGE CAPE SHOULD BE SUPPORTIVE OF SUPERCELLS...BEFORE CONSIDERABLE
UPSCALE GROWTH OCCURS BY EARLY EVENING.
VERY LARGE HAIL IS POSSIBLE IN STRONGEST CELLS. A COUPLE OF
TORNADOES ARE ALSO POSSIBLE...BUT TORNADIC POTENTIAL MAY BE HINDERED
BY WEAKNESS IN MID-LEVEL FLOW...AND A TENDENCY FOR STORMS TO QUICKLY
GENERATE CONSIDERABLE OUTFLOW.
...NORTHERN ROCKIES...
ALTHOUGH MOISTURE APPEARS TO REMAIN LIMITED ACROSS THE BASINS
WEST/SOUTH OF THE LARAMIE AND BIG HORN MOUNTAINS OF WYOMING... THE
ENVIRONMENT APPEARS AT LEAST MARGINALLY CONDUCIVE TO ISOLATED
SUPERCELL DEVELOPMENT LATE THIS AFTERNOON/EVENING...SOME OF WHICH
COULD DEVELOP/SPREAD NORTH/EAST OF THE MOUNTAINS INTO PARTS OF
EASTERN WYOMING AND MONTANA.
..KERR/BUNTING.. 05/23/2013
000
ACUS01 KWNS 231622
SWODY1
SPC AC 231620
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1120 AM CDT THU MAY 23 2013
VALID 231630Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS LATE THIS AFTN AND EVE ACROSS
PARTS OF THE EASTERN TEXAS PANHANDLE AND NORTHWEST TEXAS...
...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK
AREA ACROSS THE SOUTHERN PLAINS AND RED RIVER VALLEY REGION...
...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE MID
ATLANTIC STATES INTO NEW ENGLAND...
...SYNOPSIS...
WHILE THE CURRENT BLOCKING PATTERN OVER NORTH AMERICA IS EXPECTED TO
BECOME A BIT LESS PROMINENT...LARGE-SCALE MID/UPPER FLOW OVER THE
U.S. IS EXPECTED TO REMAIN AMPLIFIED AND SLOW TO CHANGE. IN THE
EAST...THE TRANSITION OF A CLOSED LOW TO AN OPEN WAVE TROUGH
CONTINUES ACROSS THE GREAT LAKES AND LOWER OHIO VALLEY REGION...TO
THE SOUTH OF A SHORT WAVE TROUGH SLOWLY DIGGING SOUTHEAST OF THE
HUDSON/JAMES BAY REGION. BOTH THESE FEATURES WILL CONTINUE TO
GRADUALLY TURN EASTWARD/SOUTHEASTWARD TOWARD THE ATLANTIC SEABOARD
LATER TODAY AND TONIGHT. AT THE SAME TIME...A DEEP MID-LEVEL CLOSED
LOW WILL LINGER OVER THE PACIFIC NORTHWEST...WITH BROADER SCALE
UPPER TROUGHING ENCOMPASSING MUCH OF THE PACIFIC COAST STATES INTO
THE ROCKIES. A SIGNIFICANT MID-LEVEL IMPULSE IS EXPECTED TO
CONTINUE TO GRADUALLY PIVOT AROUND THE LOW...ACROSS THE NORTHERN
GREAT BASIN INTO THE NORTHERN ROCKIES BY LATE TONIGHT. THIS WILL
SUPPRESS MID-LEVEL HEIGHT RISES ACROSS PARTS OF THE NORTHERN
PLAINS...WHILE MID/UPPER RIDGING REMAINS OR BECOME MORE PROMINENT
ACROSS MUCH OF THE PLAINS INTO THE MISSISSIPPI VALLEY REGION. A
COUPLE OF WEAK IMPULSES PROGRESSING THROUGH THE CYCLONIC FLOW ACROSS
THE SOUTHERN PLATEAU INTO THE SOUTHERN ROCKIES REGION MAY HAVE AT
LEAST A GLANCING IMPACT ON PARTS OF THE SOUTHERN PLAINS...HOWEVER.
...MID ATLANTIC STATES INTO THE NORTHEAST...
AHEAD/EAST OF A COLD FRONT ADVANCING ACROSS THE LOWER GREAT LAKES
AND OHIO VALLEY REGION...MID-LEVEL LAPSE RATES APPEAR TO HAVE
STABILIZED CONSIDERABLY OVER THE PAST COUPLE OF DAYS. CONSIDERABLE
CLOUD COVER AND PRECIPITATION...SOME CONVECTIVE...IS ALREADY WELL
UNDERWAY...AND IT IS NOT CLEAR HOW MUCH DESTABILIZATION WILL TAKE
PLACE TODAY. THERE ARE BREAKS IN CLOUD COVER...WHICH WILL ALLOW FOR
AT LEAST POCKETS OF HEATING AND WEAK TO MODEST DESTABILIZATION...THE
STRONGEST OF WHICH SEEMS LIKELY TO TAKE PLACE ALONG THE LEE SURFACE
TROUGH...EAST OF THE APPALACHIANS. THIS MAY INCLUDE THE URBAN
CORRIDOR FROM WASHINGTON D.C./BALTIMORE INTO THE PHILADELPHIA AREA.
WHERE SUBSTANTIVE DESTABILIZATION IS ABLE TO TAKE PLACE...SHEAR AND
MOMENTUM ASSOCIATED WITH 20-40 KT SOUTHWESTERLY LOWER/MID
TROPOSPHERIC FLOW MAY ENHANCE CONVECTIVE DEVELOPMENT... CONTRIBUTING
TO STORM MOTION AND ORGANIZATION. STRONGEST ACTIVITY MAY BE CAPABLE
OF PRODUCING SEVERE WIND GUSTS...WITH SOMEWHAT LOWER POTENTIAL FOR
SEVERE HAIL OR A TORNADO.
...SOUTHERN PLAINS...
THE SEVERE STORM/SMALL STORM CLUSTER THAT EVOLVED FROM A LARGER
SCALE WARM ADVECTION REGIME OVER CENTRAL OKLAHOMA EARLIER THIS
MORNING IS CURRENTLY WEAKENING SOUTH OF THE RED RIVER...ACROSS PARTS
OF NORTHEAST TEXAS. IT MAY NOT BE OUT OF THE QUESTION THAT REMNANTS
OF THIS ACTIVITY COULD BE ASSOCIATED WITH NEW INTENSE STORM
DEVELOPMENT ACROSS PARTS OF EASTERN TEXAS INTO LOUISIANA LATER
TODAY...IN THE PRESENCE OF POTENTIALLY STRONG INSTABILITY.
HOWEVER...THE PRIMARY CONVECTIVE POTENTIAL IS EXPECTED TO BECOME
FOCUSED NEAR THE DRYLINE AND A DEVELOPING WARM FRONT ACROSS THE
SOUTHERN HIGH PLAINS LATER THIS AFTERNOON AND EVENING.
DESPITE THE TENDENCY FOR CONTINUING WEAK MID-LEVEL HEIGHT RISES
ACROSS THE SOUTHERN PLAINS TODAY...MODELS SUGGEST CONVECTIVE
INHIBITION WILL WEAKEN SUFFICIENTLY BY PEAK AFTERNOON HEATING FOR
STORM INITIATION ON THE DRYLINE. THE MOST INTENSE STORMS/GREATEST
STORM COVERAGE IS EXPECTED NEAR THE DRYLINE/WARM FRONT
INTERSECTION...EAST/SOUTHEAST OF LUBBOCK AND AMARILLO INTO AREAS OF
NORTHWEST TEXAS NEAR/SOUTH OF CHILDRESS. THIS IS WHERE
THERMODYNAMIC PROFILES WITH VERY STEEP MID-LEVEL LAPSE RATES AND
LARGE CAPE SHOULD BE SUPPORTIVE OF SUPERCELLS...BEFORE CONSIDERABLE
UPSCALE GROWTH OCCURS BY EARLY EVENING.
VERY LARGE HAIL IS POSSIBLE IN STRONGEST CELLS. A COUPLE OF
TORNADOES ARE ALSO POSSIBLE...BUT TORNADIC POTENTIAL MAY BE HINDERED
BY WEAKNESS IN MID-LEVEL FLOW...AND A TENDENCY FOR STORMS TO QUICKLY
GENERATE CONSIDERABLE OUTFLOW.
...NORTHERN ROCKIES...
ALTHOUGH MOISTURE APPEARS TO REMAIN LIMITED ACROSS THE BASINS
WEST/SOUTH OF THE LARAMIE AND BIG HORN MOUNTAINS OF WYOMING... THE
ENVIRONMENT APPEARS AT LEAST MARGINALLY CONDUCIVE TO ISOLATED
SUPERCELL DEVELOPMENT LATE THIS AFTERNOON/EVENING...SOME OF WHICH
COULD DEVELOP/SPREAD NORTH/EAST OF THE MOUNTAINS INTO PARTS OF
EASTERN WYOMING AND MONTANA.
..KERR/BUNTING.. 05/23/2013
000
ACUS11 KWNS 231550
SWOMCD
SPC MCD 231550
PAZ000-MDZ000-WVZ000-OHZ000-231745-
MESOSCALE DISCUSSION 0780
NWS STORM PREDICTION CENTER NORMAN OK
1050 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER OH VALLEY/CNTRL APPALACHIANS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231550Z - 231745Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...ISOLATED DAMAGING WIND/MARGINAL SEVERE HAIL HAZARD SHOULD
DEVELOP AS CONVECTION DEEPENS ACROSS THE UPPER OH VALLEY. WEAKER
DEEP-LAYER FLOW RELATIVE TO AREAS NEWD MAY TEMPER THE OVERALL
COVERAGE/INTENSITY OF THE THREAT.
DISCUSSION...AN ARC OF SHOWERS AND ISOLATED TSTMS HAVE DEVELOPED
FROM 30 E ZZV NEAR HTS ALONG A RELATIVELY DIFFUSE COLD FRONT. A
DEEPENING CU FIELD WAS NOTED IN VISIBLE SATELLITE IMAGERY AHEAD OF
THE FRONT FROM ERN KY INTO WRN PA. AS SURFACE TEMPERATURES CONTINUE
TO WARM THROUGH THE 70S...MLCAPE SHOULD APPROACH 1000 J/KG GIVEN THE
EXPECTED MAINTENANCE OF LOWER 60S SURFACE DEW POINTS.
HOWEVER...MORNING MODEL GUIDANCE REMAINS INSISTENT THAT 700 MB WINDS
WILL SUBSIDE THIS AFTERNOON. WITH EFFECTIVE SHEAR AROUND 30 KT AT
PRESENT...OVERALL SETUP WILL MOST LIKELY YIELD A FEW MULTICELL
CLUSTERS CAPABLE OF ISOLATED DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37908226 38298240 39048169 39808124 40458105 40918040
41067943 40957854 40777825 40337834 39527892 38158013
37738095 37628167 37908226
000
ACUS11 KWNS 231550
SWOMCD
SPC MCD 231550
PAZ000-MDZ000-WVZ000-OHZ000-231745-
MESOSCALE DISCUSSION 0780
NWS STORM PREDICTION CENTER NORMAN OK
1050 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER OH VALLEY/CNTRL APPALACHIANS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231550Z - 231745Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...ISOLATED DAMAGING WIND/MARGINAL SEVERE HAIL HAZARD SHOULD
DEVELOP AS CONVECTION DEEPENS ACROSS THE UPPER OH VALLEY. WEAKER
DEEP-LAYER FLOW RELATIVE TO AREAS NEWD MAY TEMPER THE OVERALL
COVERAGE/INTENSITY OF THE THREAT.
DISCUSSION...AN ARC OF SHOWERS AND ISOLATED TSTMS HAVE DEVELOPED
FROM 30 E ZZV NEAR HTS ALONG A RELATIVELY DIFFUSE COLD FRONT. A
DEEPENING CU FIELD WAS NOTED IN VISIBLE SATELLITE IMAGERY AHEAD OF
THE FRONT FROM ERN KY INTO WRN PA. AS SURFACE TEMPERATURES CONTINUE
TO WARM THROUGH THE 70S...MLCAPE SHOULD APPROACH 1000 J/KG GIVEN THE
EXPECTED MAINTENANCE OF LOWER 60S SURFACE DEW POINTS.
HOWEVER...MORNING MODEL GUIDANCE REMAINS INSISTENT THAT 700 MB WINDS
WILL SUBSIDE THIS AFTERNOON. WITH EFFECTIVE SHEAR AROUND 30 KT AT
PRESENT...OVERALL SETUP WILL MOST LIKELY YIELD A FEW MULTICELL
CLUSTERS CAPABLE OF ISOLATED DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37908226 38298240 39048169 39808124 40458105 40918040
41067943 40957854 40777825 40337834 39527892 38158013
37738095 37628167 37908226
000
ACUS11 KWNS 231550
SWOMCD
SPC MCD 231550
PAZ000-MDZ000-WVZ000-OHZ000-231745-
MESOSCALE DISCUSSION 0780
NWS STORM PREDICTION CENTER NORMAN OK
1050 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER OH VALLEY/CNTRL APPALACHIANS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231550Z - 231745Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...ISOLATED DAMAGING WIND/MARGINAL SEVERE HAIL HAZARD SHOULD
DEVELOP AS CONVECTION DEEPENS ACROSS THE UPPER OH VALLEY. WEAKER
DEEP-LAYER FLOW RELATIVE TO AREAS NEWD MAY TEMPER THE OVERALL
COVERAGE/INTENSITY OF THE THREAT.
DISCUSSION...AN ARC OF SHOWERS AND ISOLATED TSTMS HAVE DEVELOPED
FROM 30 E ZZV NEAR HTS ALONG A RELATIVELY DIFFUSE COLD FRONT. A
DEEPENING CU FIELD WAS NOTED IN VISIBLE SATELLITE IMAGERY AHEAD OF
THE FRONT FROM ERN KY INTO WRN PA. AS SURFACE TEMPERATURES CONTINUE
TO WARM THROUGH THE 70S...MLCAPE SHOULD APPROACH 1000 J/KG GIVEN THE
EXPECTED MAINTENANCE OF LOWER 60S SURFACE DEW POINTS.
HOWEVER...MORNING MODEL GUIDANCE REMAINS INSISTENT THAT 700 MB WINDS
WILL SUBSIDE THIS AFTERNOON. WITH EFFECTIVE SHEAR AROUND 30 KT AT
PRESENT...OVERALL SETUP WILL MOST LIKELY YIELD A FEW MULTICELL
CLUSTERS CAPABLE OF ISOLATED DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37908226 38298240 39048169 39808124 40458105 40918040
41067943 40957854 40777825 40337834 39527892 38158013
37738095 37628167 37908226
000
ACUS11 KWNS 231524
SWOMCD
SPC MCD 231523
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-NJZ000-PAZ000-231800-
MESOSCALE DISCUSSION 0779
NWS STORM PREDICTION CENTER NORMAN OK
1023 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER MID-ATLANTIC/SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231523Z - 231800Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING ACROSS FAR
ERN PA/NRN NJ. A WW ISSUANCE MAY BECOME NECESSARY WHERE GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR IMAGERY FROM NEAR THE ABE/TTN TO 20 NW EWR AREA AS CONVECTIVE
TEMPERATURES OFF THE 12Z APG/WAL RAOBS HAVE BEEN BREACHED WITH
MIDDLE TO UPPER 70S IN 15Z METARS. AMIDST A PLUME OF MIDDLE TO UPPER
60S SURFACE DEW POINTS...MLCAPE HAS ALREADY REACHED 500-1000 J/KG.
MODERATELY STRONG UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT
ENTRANCE REGION OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL
CONVECTION WHICH MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS
PRIMARILY PRODUCING SPORADIC DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...
LAT...LON 43067382 43317289 43077200 42707193 42077223 41467298
41107349 40717386 40247443 40187490 40487540 40767527
42097440 43067382
000
ACUS11 KWNS 231524
SWOMCD
SPC MCD 231523
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-NJZ000-PAZ000-231800-
MESOSCALE DISCUSSION 0779
NWS STORM PREDICTION CENTER NORMAN OK
1023 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER MID-ATLANTIC/SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231523Z - 231800Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING ACROSS FAR
ERN PA/NRN NJ. A WW ISSUANCE MAY BECOME NECESSARY WHERE GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR IMAGERY FROM NEAR THE ABE/TTN TO 20 NW EWR AREA AS CONVECTIVE
TEMPERATURES OFF THE 12Z APG/WAL RAOBS HAVE BEEN BREACHED WITH
MIDDLE TO UPPER 70S IN 15Z METARS. AMIDST A PLUME OF MIDDLE TO UPPER
60S SURFACE DEW POINTS...MLCAPE HAS ALREADY REACHED 500-1000 J/KG.
MODERATELY STRONG UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT
ENTRANCE REGION OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL
CONVECTION WHICH MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS
PRIMARILY PRODUCING SPORADIC DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...
LAT...LON 43067382 43317289 43077200 42707193 42077223 41467298
41107349 40717386 40247443 40187490 40487540 40767527
42097440 43067382
000
ACUS11 KWNS 231524
SWOMCD
SPC MCD 231523
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-NJZ000-PAZ000-231800-
MESOSCALE DISCUSSION 0779
NWS STORM PREDICTION CENTER NORMAN OK
1023 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF THE UPPER MID-ATLANTIC/SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231523Z - 231800Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING ACROSS FAR
ERN PA/NRN NJ. A WW ISSUANCE MAY BECOME NECESSARY WHERE GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR IMAGERY FROM NEAR THE ABE/TTN TO 20 NW EWR AREA AS CONVECTIVE
TEMPERATURES OFF THE 12Z APG/WAL RAOBS HAVE BEEN BREACHED WITH
MIDDLE TO UPPER 70S IN 15Z METARS. AMIDST A PLUME OF MIDDLE TO UPPER
60S SURFACE DEW POINTS...MLCAPE HAS ALREADY REACHED 500-1000 J/KG.
MODERATELY STRONG UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT
ENTRANCE REGION OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL
CONVECTION WHICH MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS
PRIMARILY PRODUCING SPORADIC DAMAGING WINDS AND MARGINALLY SEVERE
HAIL.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...
LAT...LON 43067382 43317289 43077200 42707193 42077223 41467298
41107349 40717386 40247443 40187490 40487540 40767527
42097440 43067382
000
ACUS11 KWNS 231458
SWOMCD
SPC MCD 231457
NYZ000-PAZ000-231730-
MESOSCALE DISCUSSION 0778
NWS STORM PREDICTION CENTER NORMAN OK
0957 AM CDT THU MAY 23 2013
AREAS AFFECTED...WRN/CNTRL/NRN PORTIONS OF NY/PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231457Z - 231730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD TODAY WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING WRN
NY INTO NWRN PA. A WW ISSUANCE MAY BECOME NECESSARY WHEN GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR/VISIBLE SATELLITE IMAGERY FROM NEAR ROC SWWD TO FKL. AS
CONVECTIVE TEMPERATURES OFF THE 12Z BUF/PIT RAOBS HAVE BEEN
BREACHED. RELATIVELY ABUNDANT LOW CLOUD COVERAGE REMAINS DOWNSTREAM
OF THIS WHICH IS RETARDING SURFACE HEATING...BUT GRADUAL
DESTABILIZATION AMIDST THE PRESENCE OF 10-12 G/KG MEAN MIXING RATIOS
MAY YIELD POCKETS OF MLCAPE FROM 500-1000 J/KG. MODERATELY STRONG
UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT ENTRANCE REGION
OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL CONVECTION WHICH
MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ...
LAT...LON 43167705 43597626 44167566 44447522 44337450 43977408
43407431 42267535 41557649 40617833 40587921 40907967
41357969 43167705
000
ACUS11 KWNS 231458
SWOMCD
SPC MCD 231457
NYZ000-PAZ000-231730-
MESOSCALE DISCUSSION 0778
NWS STORM PREDICTION CENTER NORMAN OK
0957 AM CDT THU MAY 23 2013
AREAS AFFECTED...WRN/CNTRL/NRN PORTIONS OF NY/PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231457Z - 231730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD TODAY WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING WRN
NY INTO NWRN PA. A WW ISSUANCE MAY BECOME NECESSARY WHEN GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR/VISIBLE SATELLITE IMAGERY FROM NEAR ROC SWWD TO FKL. AS
CONVECTIVE TEMPERATURES OFF THE 12Z BUF/PIT RAOBS HAVE BEEN
BREACHED. RELATIVELY ABUNDANT LOW CLOUD COVERAGE REMAINS DOWNSTREAM
OF THIS WHICH IS RETARDING SURFACE HEATING...BUT GRADUAL
DESTABILIZATION AMIDST THE PRESENCE OF 10-12 G/KG MEAN MIXING RATIOS
MAY YIELD POCKETS OF MLCAPE FROM 500-1000 J/KG. MODERATELY STRONG
UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT ENTRANCE REGION
OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL CONVECTION WHICH
MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ...
LAT...LON 43167705 43597626 44167566 44447522 44337450 43977408
43407431 42267535 41557649 40617833 40587921 40907967
41357969 43167705
000
ACUS11 KWNS 231458
SWOMCD
SPC MCD 231457
NYZ000-PAZ000-231730-
MESOSCALE DISCUSSION 0778
NWS STORM PREDICTION CENTER NORMAN OK
0957 AM CDT THU MAY 23 2013
AREAS AFFECTED...WRN/CNTRL/NRN PORTIONS OF NY/PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231457Z - 231730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...MONITORING FOR AN INCREASING DAMAGING WIND/MARGINAL SEVERE
HAIL HAZARD TODAY WITH INITIAL CONVECTIVE DEVELOPMENT OCCURRING WRN
NY INTO NWRN PA. A WW ISSUANCE MAY BECOME NECESSARY WHEN GREATER
CLUSTER/LINEAR ORGANIZATION IS APPARENT.
DISCUSSION...AN INCREASE IN CONVECTIVE DEVELOPMENT HAS BEEN NOTED IN
RADAR/VISIBLE SATELLITE IMAGERY FROM NEAR ROC SWWD TO FKL. AS
CONVECTIVE TEMPERATURES OFF THE 12Z BUF/PIT RAOBS HAVE BEEN
BREACHED. RELATIVELY ABUNDANT LOW CLOUD COVERAGE REMAINS DOWNSTREAM
OF THIS WHICH IS RETARDING SURFACE HEATING...BUT GRADUAL
DESTABILIZATION AMIDST THE PRESENCE OF 10-12 G/KG MEAN MIXING RATIOS
MAY YIELD POCKETS OF MLCAPE FROM 500-1000 J/KG. MODERATELY STRONG
UNIDIRECTIONAL SWLY WIND PROFILES WITHIN THE RIGHT ENTRANCE REGION
OF A FAST UPPER-LEVEL JET SHOULD PROMOTE ADDITIONAL CONVECTION WHICH
MAY ORGANIZE INTO CLUSTERS AND SHORT-LINE SEGMENTS.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ...
LAT...LON 43167705 43597626 44167566 44447522 44337450 43977408
43407431 42267535 41557649 40617833 40587921 40907967
41357969 43167705
000
ACUS11 KWNS 231353
SWOMCD
SPC MCD 231352
OKZ000-TXZ000-231445-
MESOSCALE DISCUSSION 0777
NWS STORM PREDICTION CENTER NORMAN OK
0852 AM CDT THU MAY 23 2013
AREAS AFFECTED...FAR S-CNTRL OK/N-CNTRL TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231352Z - 231445Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...INTENSE SUPERCELL NEAR ADM CAPABLE OF ISOLATED VERY LARGE
HAIL AND SEVERE WIND GUSTS IS EXPECTED TO GRADUALLY WEAKEN AS IT
TRACKS SEWD TOWARDS THE RED RIVER. IF WEAKENING DOES NOT OCCUR
WITHIN THE NEXT 30-60 MINUTES...A SEVERE TSTM WATCH ISSUANCE MAY
OCCUR.
DISCUSSION...PORTION OF CNTRL OK MCS HAS ACCELERATED S/SEWD WITH
INTENSE REFLECTIVITY SIGNATURES AND HAIL TO TENNIS BALL SIZE
RECENTLY REPORTED. EXPECTATIONS WERE FOR THIS ACTIVITY TO WEAKEN
THROUGH THE MORNING HOURS...AS THE LLJ HAS COMMENCED DIMINISHING PER
FDR/FWS VWP DATA AND AS THE SUPERCELL CLUSTER SHIFTS AWAY FROM THE
TIGHTER THERMAL GRADIENT AT 700 MB. THE 00Z NSSL-WRF SIMULATED THIS
CLUSTER QUITE WELL AND SUGGESTS ACTIVITY WILL DIMINISH BY NOON.
NEVERTHELESS...WITH THE CLUSTER RIDING ALONG THE MUCAPE GRADIENT AND
DEVELOPING TOWARDS POTENTIALLY GREATER BUOYANCY...THERE IS SOME
UNCERTAINTY OVER WHETHER THIS CLUSTER MAY PERSIST WITH A SEVERE
THREAT EVEN AS FORCING FOR ASCENT WANES.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...FWD...OUN...
LAT...LON 34629674 34179584 33719581 33199605 32939674 33019718
33199759 33719781 34129791 34439750 34629674
000
ACUS11 KWNS 231353
SWOMCD
SPC MCD 231352
OKZ000-TXZ000-231445-
MESOSCALE DISCUSSION 0777
NWS STORM PREDICTION CENTER NORMAN OK
0852 AM CDT THU MAY 23 2013
AREAS AFFECTED...FAR S-CNTRL OK/N-CNTRL TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231352Z - 231445Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...INTENSE SUPERCELL NEAR ADM CAPABLE OF ISOLATED VERY LARGE
HAIL AND SEVERE WIND GUSTS IS EXPECTED TO GRADUALLY WEAKEN AS IT
TRACKS SEWD TOWARDS THE RED RIVER. IF WEAKENING DOES NOT OCCUR
WITHIN THE NEXT 30-60 MINUTES...A SEVERE TSTM WATCH ISSUANCE MAY
OCCUR.
DISCUSSION...PORTION OF CNTRL OK MCS HAS ACCELERATED S/SEWD WITH
INTENSE REFLECTIVITY SIGNATURES AND HAIL TO TENNIS BALL SIZE
RECENTLY REPORTED. EXPECTATIONS WERE FOR THIS ACTIVITY TO WEAKEN
THROUGH THE MORNING HOURS...AS THE LLJ HAS COMMENCED DIMINISHING PER
FDR/FWS VWP DATA AND AS THE SUPERCELL CLUSTER SHIFTS AWAY FROM THE
TIGHTER THERMAL GRADIENT AT 700 MB. THE 00Z NSSL-WRF SIMULATED THIS
CLUSTER QUITE WELL AND SUGGESTS ACTIVITY WILL DIMINISH BY NOON.
NEVERTHELESS...WITH THE CLUSTER RIDING ALONG THE MUCAPE GRADIENT AND
DEVELOPING TOWARDS POTENTIALLY GREATER BUOYANCY...THERE IS SOME
UNCERTAINTY OVER WHETHER THIS CLUSTER MAY PERSIST WITH A SEVERE
THREAT EVEN AS FORCING FOR ASCENT WANES.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...FWD...OUN...
LAT...LON 34629674 34179584 33719581 33199605 32939674 33019718
33199759 33719781 34129791 34439750 34629674
000
ACUS11 KWNS 231353
SWOMCD
SPC MCD 231352
OKZ000-TXZ000-231445-
MESOSCALE DISCUSSION 0777
NWS STORM PREDICTION CENTER NORMAN OK
0852 AM CDT THU MAY 23 2013
AREAS AFFECTED...FAR S-CNTRL OK/N-CNTRL TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 231352Z - 231445Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...INTENSE SUPERCELL NEAR ADM CAPABLE OF ISOLATED VERY LARGE
HAIL AND SEVERE WIND GUSTS IS EXPECTED TO GRADUALLY WEAKEN AS IT
TRACKS SEWD TOWARDS THE RED RIVER. IF WEAKENING DOES NOT OCCUR
WITHIN THE NEXT 30-60 MINUTES...A SEVERE TSTM WATCH ISSUANCE MAY
OCCUR.
DISCUSSION...PORTION OF CNTRL OK MCS HAS ACCELERATED S/SEWD WITH
INTENSE REFLECTIVITY SIGNATURES AND HAIL TO TENNIS BALL SIZE
RECENTLY REPORTED. EXPECTATIONS WERE FOR THIS ACTIVITY TO WEAKEN
THROUGH THE MORNING HOURS...AS THE LLJ HAS COMMENCED DIMINISHING PER
FDR/FWS VWP DATA AND AS THE SUPERCELL CLUSTER SHIFTS AWAY FROM THE
TIGHTER THERMAL GRADIENT AT 700 MB. THE 00Z NSSL-WRF SIMULATED THIS
CLUSTER QUITE WELL AND SUGGESTS ACTIVITY WILL DIMINISH BY NOON.
NEVERTHELESS...WITH THE CLUSTER RIDING ALONG THE MUCAPE GRADIENT AND
DEVELOPING TOWARDS POTENTIALLY GREATER BUOYANCY...THERE IS SOME
UNCERTAINTY OVER WHETHER THIS CLUSTER MAY PERSIST WITH A SEVERE
THREAT EVEN AS FORCING FOR ASCENT WANES.
..GRAMS/KERR.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...FWD...OUN...
LAT...LON 34629674 34179584 33719581 33199605 32939674 33019718
33199759 33719781 34129791 34439750 34629674
000
ACUS01 KWNS 231227
SWODY1
SPC AC 231225
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0725 AM CDT THU MAY 23 2013
VALID 231300Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER A SMALL PORTION OF
NORTHWEST TX...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF OK/TX...
...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE EASTERN
UNITED STATES...
...NORTHEAST STATES...
A BROAD UPPER TROUGH REMAINS OVER THE MS AND OH VALLEYS THIS
MORNING. THIS TROUGH WILL MOVE SLOWLY EASTWARD INTO THE
APPALACHIANS TODAY...PROVIDING A FAVORABLE SYNOPTIC ENVIRONMENT FOR
SCATTERED THUNDERSTORMS FROM NEW ENGLAND SOUTHWARD INTO THE
CAROLINAS. BROKEN CLOUD COVER WILL SLOW DAYTIME HEATING THIS
MORNING...BUT SUFFICIENT DESTABILIZATION SHOULD RESULT FOR
THUNDERSTORMS INCREASING IN COVERAGE BY EARLY AFTERNOON. DEWPOINTS
IN THE MID 60S COUPLED WITH 20-30 KNOTS OF EFFECTIVE SHEAR SHOULD BE
SUFFICIENT FOR ORGANIZED MULTICELL STORMS CAPABLE OF DAMAGING WINDS
AND SOME HAIL. THE GREATEST COVERAGE OF STRONG STORMS IS EXPECTED
FROM EASTERN PA/NY INTO WESTERN NEW ENGLAND. HOWEVER...AT LEAST
ISOLATED SEVERE STORMS APPEAR POSSIBLE SOUTHWARD INTO PARTS OF MD/VA
AND NC. STORMS IN THESE AREAS SHOULD WEAKEN RATHER QUICKLY AFTER
SUNSET.
...TX/OK...
A CLUSTER OF STRONG/SEVERE THUNDERSTORMS IS ONGOING THIS MORNING
OVER CENTRAL OK. THESE STORMS WILL LIKELY PERSIST FOR A FEW MORE
HOURS AND SPREAD SOUTH-SOUTHEASTWARD INTO SOUTHERN OK AND NORTH TX.
TO THE SOUTHWEST OF THIS ACTIVITY...SOUTHERLY LOW LEVEL WINDS WILL
TRANSPORT RICH GULF MOISTURE NORTHWARD BENEATH A RATHER STOUT
CAPPING INVERSION. BY LATE AFTERNOON...MOST MODEL SOLUTIONS
INDICATE SURFACE DEWPOINTS IN THE UPPER 60S AS FAR NORTHWEST AS THE
CDS AREA ALONG WITH FULL HEATING ALL DAY. FORECAST SOUNDINGS IN
THIS AREA SHOW VERY STEEP MID LEVEL LAPSE RATES /OVER 8.0 C/KM/ AND
MLCAPE VALUES OVER 4000 J/KG. WHILE THE THERMODYNAMIC PARAMETERS
ARE FORECAST TO BE EXCEPTIONAL...THIS REGION WILL BE UNDER A WEAK
UPPER RIDGE WITH ONLY SUBTLE FORCING MECHANISMS EXPECTED TO AID IN
CONVECTIVE DEVELOPMENT.
CURRENT SATELLITE IMAGERY SUGGESTS A SHORTWAVE TROUGH SOUTH OF TUS.
GIVEN CURRENT MOTION...THIS TROUGH WILL BE OVER WEST TX AROUND 21Z.
MEANWHILE...SEVERAL MODEL SOLUTIONS INDICATE THAT AN OUTFLOW
BOUNDARY WILL SAG SOUTHWARD FROM THE MORNING CONVECTION OVER OK AND
LIE ACROSS NORTHWEST TX AROUND THE SAME TIME. IF THIS SERIES OF
EVENTS CAN COME TOGETHER...THERE APPEARS TO BE A RATHER SMALL AREA
OF ENHANCED THREAT OF SIGNIFICANT SEVERE THUNDERSTORMS LATER TODAY.
THIS AREA HAS BEEN UPGRADED TO MODERATE RISK. LARGE/SLOW-MOVING
SUPERCELL STORMS ARE FORECAST TO DEVELOP IN THE MODERATE RISK
AREA...CAPABLE OF VERY LARGE HAIL AND A FEW TORNADOES. THE STORMS
MAY GROW UPSCALE AND SPREAD SOUTHEASTWARD BEFORE WEAKENING LATE THIS
EVENING.
..HART/LEITMAN.. 05/23/2013
000
ACUS01 KWNS 231227
SWODY1
SPC AC 231225
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0725 AM CDT THU MAY 23 2013
VALID 231300Z - 241200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER A SMALL PORTION OF
NORTHWEST TX...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF OK/TX...
...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE EASTERN
UNITED STATES...
...NORTHEAST STATES...
A BROAD UPPER TROUGH REMAINS OVER THE MS AND OH VALLEYS THIS
MORNING. THIS TROUGH WILL MOVE SLOWLY EASTWARD INTO THE
APPALACHIANS TODAY...PROVIDING A FAVORABLE SYNOPTIC ENVIRONMENT FOR
SCATTERED THUNDERSTORMS FROM NEW ENGLAND SOUTHWARD INTO THE
CAROLINAS. BROKEN CLOUD COVER WILL SLOW DAYTIME HEATING THIS
MORNING...BUT SUFFICIENT DESTABILIZATION SHOULD RESULT FOR
THUNDERSTORMS INCREASING IN COVERAGE BY EARLY AFTERNOON. DEWPOINTS
IN THE MID 60S COUPLED WITH 20-30 KNOTS OF EFFECTIVE SHEAR SHOULD BE
SUFFICIENT FOR ORGANIZED MULTICELL STORMS CAPABLE OF DAMAGING WINDS
AND SOME HAIL. THE GREATEST COVERAGE OF STRONG STORMS IS EXPECTED
FROM EASTERN PA/NY INTO WESTERN NEW ENGLAND. HOWEVER...AT LEAST
ISOLATED SEVERE STORMS APPEAR POSSIBLE SOUTHWARD INTO PARTS OF MD/VA
AND NC. STORMS IN THESE AREAS SHOULD WEAKEN RATHER QUICKLY AFTER
SUNSET.
...TX/OK...
A CLUSTER OF STRONG/SEVERE THUNDERSTORMS IS ONGOING THIS MORNING
OVER CENTRAL OK. THESE STORMS WILL LIKELY PERSIST FOR A FEW MORE
HOURS AND SPREAD SOUTH-SOUTHEASTWARD INTO SOUTHERN OK AND NORTH TX.
TO THE SOUTHWEST OF THIS ACTIVITY...SOUTHERLY LOW LEVEL WINDS WILL
TRANSPORT RICH GULF MOISTURE NORTHWARD BENEATH A RATHER STOUT
CAPPING INVERSION. BY LATE AFTERNOON...MOST MODEL SOLUTIONS
INDICATE SURFACE DEWPOINTS IN THE UPPER 60S AS FAR NORTHWEST AS THE
CDS AREA ALONG WITH FULL HEATING ALL DAY. FORECAST SOUNDINGS IN
THIS AREA SHOW VERY STEEP MID LEVEL LAPSE RATES /OVER 8.0 C/KM/ AND
MLCAPE VALUES OVER 4000 J/KG. WHILE THE THERMODYNAMIC PARAMETERS
ARE FORECAST TO BE EXCEPTIONAL...THIS REGION WILL BE UNDER A WEAK
UPPER RIDGE WITH ONLY SUBTLE FORCING MECHANISMS EXPECTED TO AID IN
CONVECTIVE DEVELOPMENT.
CURRENT SATELLITE IMAGERY SUGGESTS A SHORTWAVE TROUGH SOUTH OF TUS.
GIVEN CURRENT MOTION...THIS TROUGH WILL BE OVER WEST TX AROUND 21Z.
MEANWHILE...SEVERAL MODEL SOLUTIONS INDICATE THAT AN OUTFLOW
BOUNDARY WILL SAG SOUTHWARD FROM THE MORNING CONVECTION OVER OK AND
LIE ACROSS NORTHWEST TX AROUND THE SAME TIME. IF THIS SERIES OF
EVENTS CAN COME TOGETHER...THERE APPEARS TO BE A RATHER SMALL AREA
OF ENHANCED THREAT OF SIGNIFICANT SEVERE THUNDERSTORMS LATER TODAY.
THIS AREA HAS BEEN UPGRADED TO MODERATE RISK. LARGE/SLOW-MOVING
SUPERCELL STORMS ARE FORECAST TO DEVELOP IN THE MODERATE RISK
AREA...CAPABLE OF VERY LARGE HAIL AND A FEW TORNADOES. THE STORMS
MAY GROW UPSCALE AND SPREAD SOUTHEASTWARD BEFORE WEAKENING LATE THIS
EVENING.
..HART/LEITMAN.. 05/23/2013
000
ACUS11 KWNS 230945
SWOMCD
SPC MCD 230945
OKZ000-231145-
MESOSCALE DISCUSSION 0776
NWS STORM PREDICTION CENTER NORMAN OK
0445 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF CENTRAL AND SRN OK
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 230945Z - 231145Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ELEVATED TSTMS WILL CONTINUE TO DEVELOP DURING THE EARLY
MORNING HOURS ACROSS CENTRAL OK AND GIVEN WNWLY FLOW ALOFT...THIS
ACTIVITY WILL TRACK ESEWD INTO SOUTH CENTRAL-SERN OK. HAIL WILL BE
THE PRIMARY THREAT...WITH THE POTENTIAL FOR SOME HAILSTONES REACHING
1 INCH DIAMETER. AT THIS TIME...OVERALL SEVERE WEATHER COVERAGE IS
NOT ANTICIPATED TO SUPPORT A WATCH ISSUANCE...BUT TRENDS WILL BE
MONITORED.
DISCUSSION...EARLY MORNING RADAR MOSAIC SHOWED TSTMS DEVELOPING IN A
NARROW NW-SE ORIENTED CORRIDOR FROM BLAINE COUNTY THROUGH THE OKC
METRO INTO MCCLAIN AND CLEVELAND COUNTIES. THIS ACTIVITY IS LOCATED
WITHIN THE NOSE OF A 45-55 KT SSWLY LLJ EXTENDING FROM CENTRAL TX
INTO CENTRAL OK WHERE WAA IS BEING ENHANCED NORTH OF AN E-W ORIENTED
SURFACE BOUNDARY LOCATED ACROSS FAR N TX. DESPITE THE LACK OF ANY
APPARENT MIDLEVEL IMPULSE PER WATER VAPOR IMAGERY...AREA VWPS
INDICATED A RECENT STRENGTHENING OF NWLY MIDLEVEL WINDS OVER CENTRAL
OK /UP TO 40 KT/. THIS COMBINED WITH THE LLJ IS RESULTING IN
EFFECTIVE BULK SHEAR OF 40-50 KT...SUFFICIENT FOR STORM
ORGANIZATION. THE INFLUX OF MARGINAL-MODERATE INSTABILITY INTO
CENTRAL OK AND THE STRONGER BULK SHEAR SUGGESTS SOME OF THE STRONGER
CORES COULD INTENSIFY TO SEVERE LEVELS PRODUCING A HAIL THREAT.
MIDLEVEL LAPSE RATES HAVE INCREASED OVER CENTRAL OK SINCE 00Z...PER
THE 06Z LAMONT SOUNDING INDICATING 700-500 MB LAPSE RATES OF 8.5
C/KM. THIS FACTOR WILL FURTHER ENHANCE THE HAIL THREAT...BUT THE
LACK OF DISCERNIBLE MID-UPPER LEVEL FORCING...GIVEN HEIGHT
RISES...SHOULD LIMIT THE COVERAGE OF STRONGER STORMS.
ALTHOUGH HIGH-RES CONVECTIVE ALLOWING MODELS /00Z NAM 4KM...00Z NSSL
4 KM...AND THE 01Z HRRR/ ARE 2-3 HOURS TOO SLOW AT DEVELOPING THE
CENTRAL OK STORMS...EACH OF THESE MODELS WERE SIMILAR IN THE
EVOLUTION AND TRACK OF THESE EARLY MORNING STORMS. AND...SUGGESTED
THE OVERALL TSTM ACTIVITY WILL PERSIST FOR 5-6 HOURS THIS
MORNING...PRIOR TO THE EXPECTED WEAKENING OF THE LLJ.
..PETERS/HART.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...
LAT...LON 36329876 35979787 35619727 34899658 34479650 34079636
33939670 34129762 34509828 35129880 35809891 36329876
000
ACUS11 KWNS 230945
SWOMCD
SPC MCD 230945
OKZ000-231145-
MESOSCALE DISCUSSION 0776
NWS STORM PREDICTION CENTER NORMAN OK
0445 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF CENTRAL AND SRN OK
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 230945Z - 231145Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ELEVATED TSTMS WILL CONTINUE TO DEVELOP DURING THE EARLY
MORNING HOURS ACROSS CENTRAL OK AND GIVEN WNWLY FLOW ALOFT...THIS
ACTIVITY WILL TRACK ESEWD INTO SOUTH CENTRAL-SERN OK. HAIL WILL BE
THE PRIMARY THREAT...WITH THE POTENTIAL FOR SOME HAILSTONES REACHING
1 INCH DIAMETER. AT THIS TIME...OVERALL SEVERE WEATHER COVERAGE IS
NOT ANTICIPATED TO SUPPORT A WATCH ISSUANCE...BUT TRENDS WILL BE
MONITORED.
DISCUSSION...EARLY MORNING RADAR MOSAIC SHOWED TSTMS DEVELOPING IN A
NARROW NW-SE ORIENTED CORRIDOR FROM BLAINE COUNTY THROUGH THE OKC
METRO INTO MCCLAIN AND CLEVELAND COUNTIES. THIS ACTIVITY IS LOCATED
WITHIN THE NOSE OF A 45-55 KT SSWLY LLJ EXTENDING FROM CENTRAL TX
INTO CENTRAL OK WHERE WAA IS BEING ENHANCED NORTH OF AN E-W ORIENTED
SURFACE BOUNDARY LOCATED ACROSS FAR N TX. DESPITE THE LACK OF ANY
APPARENT MIDLEVEL IMPULSE PER WATER VAPOR IMAGERY...AREA VWPS
INDICATED A RECENT STRENGTHENING OF NWLY MIDLEVEL WINDS OVER CENTRAL
OK /UP TO 40 KT/. THIS COMBINED WITH THE LLJ IS RESULTING IN
EFFECTIVE BULK SHEAR OF 40-50 KT...SUFFICIENT FOR STORM
ORGANIZATION. THE INFLUX OF MARGINAL-MODERATE INSTABILITY INTO
CENTRAL OK AND THE STRONGER BULK SHEAR SUGGESTS SOME OF THE STRONGER
CORES COULD INTENSIFY TO SEVERE LEVELS PRODUCING A HAIL THREAT.
MIDLEVEL LAPSE RATES HAVE INCREASED OVER CENTRAL OK SINCE 00Z...PER
THE 06Z LAMONT SOUNDING INDICATING 700-500 MB LAPSE RATES OF 8.5
C/KM. THIS FACTOR WILL FURTHER ENHANCE THE HAIL THREAT...BUT THE
LACK OF DISCERNIBLE MID-UPPER LEVEL FORCING...GIVEN HEIGHT
RISES...SHOULD LIMIT THE COVERAGE OF STRONGER STORMS.
ALTHOUGH HIGH-RES CONVECTIVE ALLOWING MODELS /00Z NAM 4KM...00Z NSSL
4 KM...AND THE 01Z HRRR/ ARE 2-3 HOURS TOO SLOW AT DEVELOPING THE
CENTRAL OK STORMS...EACH OF THESE MODELS WERE SIMILAR IN THE
EVOLUTION AND TRACK OF THESE EARLY MORNING STORMS. AND...SUGGESTED
THE OVERALL TSTM ACTIVITY WILL PERSIST FOR 5-6 HOURS THIS
MORNING...PRIOR TO THE EXPECTED WEAKENING OF THE LLJ.
..PETERS/HART.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...
LAT...LON 36329876 35979787 35619727 34899658 34479650 34079636
33939670 34129762 34509828 35129880 35809891 36329876
000
ACUS11 KWNS 230945
SWOMCD
SPC MCD 230945
OKZ000-231145-
MESOSCALE DISCUSSION 0776
NWS STORM PREDICTION CENTER NORMAN OK
0445 AM CDT THU MAY 23 2013
AREAS AFFECTED...PARTS OF CENTRAL AND SRN OK
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 230945Z - 231145Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ELEVATED TSTMS WILL CONTINUE TO DEVELOP DURING THE EARLY
MORNING HOURS ACROSS CENTRAL OK AND GIVEN WNWLY FLOW ALOFT...THIS
ACTIVITY WILL TRACK ESEWD INTO SOUTH CENTRAL-SERN OK. HAIL WILL BE
THE PRIMARY THREAT...WITH THE POTENTIAL FOR SOME HAILSTONES REACHING
1 INCH DIAMETER. AT THIS TIME...OVERALL SEVERE WEATHER COVERAGE IS
NOT ANTICIPATED TO SUPPORT A WATCH ISSUANCE...BUT TRENDS WILL BE
MONITORED.
DISCUSSION...EARLY MORNING RADAR MOSAIC SHOWED TSTMS DEVELOPING IN A
NARROW NW-SE ORIENTED CORRIDOR FROM BLAINE COUNTY THROUGH THE OKC
METRO INTO MCCLAIN AND CLEVELAND COUNTIES. THIS ACTIVITY IS LOCATED
WITHIN THE NOSE OF A 45-55 KT SSWLY LLJ EXTENDING FROM CENTRAL TX
INTO CENTRAL OK WHERE WAA IS BEING ENHANCED NORTH OF AN E-W ORIENTED
SURFACE BOUNDARY LOCATED ACROSS FAR N TX. DESPITE THE LACK OF ANY
APPARENT MIDLEVEL IMPULSE PER WATER VAPOR IMAGERY...AREA VWPS
INDICATED A RECENT STRENGTHENING OF NWLY MIDLEVEL WINDS OVER CENTRAL
OK /UP TO 40 KT/. THIS COMBINED WITH THE LLJ IS RESULTING IN
EFFECTIVE BULK SHEAR OF 40-50 KT...SUFFICIENT FOR STORM
ORGANIZATION. THE INFLUX OF MARGINAL-MODERATE INSTABILITY INTO
CENTRAL OK AND THE STRONGER BULK SHEAR SUGGESTS SOME OF THE STRONGER
CORES COULD INTENSIFY TO SEVERE LEVELS PRODUCING A HAIL THREAT.
MIDLEVEL LAPSE RATES HAVE INCREASED OVER CENTRAL OK SINCE 00Z...PER
THE 06Z LAMONT SOUNDING INDICATING 700-500 MB LAPSE RATES OF 8.5
C/KM. THIS FACTOR WILL FURTHER ENHANCE THE HAIL THREAT...BUT THE
LACK OF DISCERNIBLE MID-UPPER LEVEL FORCING...GIVEN HEIGHT
RISES...SHOULD LIMIT THE COVERAGE OF STRONGER STORMS.
ALTHOUGH HIGH-RES CONVECTIVE ALLOWING MODELS /00Z NAM 4KM...00Z NSSL
4 KM...AND THE 01Z HRRR/ ARE 2-3 HOURS TOO SLOW AT DEVELOPING THE
CENTRAL OK STORMS...EACH OF THESE MODELS WERE SIMILAR IN THE
EVOLUTION AND TRACK OF THESE EARLY MORNING STORMS. AND...SUGGESTED
THE OVERALL TSTM ACTIVITY WILL PERSIST FOR 5-6 HOURS THIS
MORNING...PRIOR TO THE EXPECTED WEAKENING OF THE LLJ.
..PETERS/HART.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...
LAT...LON 36329876 35979787 35619727 34899658 34479650 34079636
33939670 34129762 34509828 35129880 35809891 36329876
000
ACUS03 KWNS 230715
SWODY3
SPC AC 230714
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0214 AM CDT THU MAY 23 2013
VALID 251200Z - 261200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
VERY SLOW/MINOR PROGRESSION OF THE UPPER PATTERN IS FORECAST FOR
SATURDAY /DAY 3/...THOUGH THE OVERALL WRN TROUGH/CENTRAL RIDGE/ERN
TROUGH PATTERN WILL PERSIST. AT THE SURFACE...A LOW IS PROGGED TO
DEEPEN JUST OFF THE NEW ENGLAND COAST...BUT OTHERWISE HIGH PRESSURE
SHOULD CONTINUE TO PREVAIL E OF THE MS RIVER VALLEY. FARTHER
W...LEE TROUGHING WILL AGAIN SERVE AS A MAIN FOCUS FOR ISOLATED
CONVECTIVE DEVELOPMENT.
...NRN HIGH PLAINS...
SATURDAY WILL LIKELY BE A VERY SIMILAR DAY TO FRIDAY /DAY 2/...WITH
THE RIDGING ACROSS THE PLAINS AND RESULTING LARGE-SCALE
SUBSIDENCE/CAPPING LARGELY HINDERING CONVECTIVE
DEVELOPMENT/INTENSITY. WHILE VERY ISOLATED SEVERE POTENTIAL WILL
AGAIN EXIST ACROSS THE CENTRAL AND SRN HIGH PLAINS...SOMEWHAT
GREATER THREAT MAY EVOLVE ACROSS THE ERN MT/WRN SD VICINITY DURING
THE LATE AFTERNOON.
HERE...MODELS HINT THAT A MID-LEVEL SHORT-WAVE FEATURE MAY EJECT
NEWD AROUND THE SERN PERIPHERY OF THE MAIN WRN TROUGH TOWARD THE NRN
HIGH PLAINS. AS THIS OCCURS...CAP WEAKENING AND ISOLATED STORM
DEVELOPMENT APPEARS POSSIBLE NEAR THE LEE TROUGH/WITHIN UPSLOPING
LOW-LEVEL SELYS. WITH 35 KT SWLYS AT MID LEVELS ANTICIPATED...SHEAR
WOULD SUPPORT UPDRAFT ORGANIZATION/ROTATION AND ATTENDANT SEVERE
POTENTIAL. THUS -- WILL FOCUS LOW SEVERE PROBABILITY ACROSS THE NRN
HIGH PLAINS REGION THIS FORECAST.
..GOSS.. 05/23/2013
000
ACUS02 KWNS 230555
SWODY2
SPC AC 230554
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1254 AM CDT THU MAY 23 2013
VALID 241200Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
AS THE UPPER TROUGH OVER THE ERN U.S. MAKES SLOW EWD PROGRESS THIS
PERIOD...THE UPSTREAM/CENTRAL U.S. RIDGE WILL EXPAND EWD WITH TIME.
MEANWHILE FARTHER W...A LARGE UPPER TROUGH WILL REMAIN IN PLACE OVER
THE WRN STATES THROUGH THE PERIOD.
AT THE SURFACE...EXPECT AN ERN U.S. COLD FRONT TO MOVE OFFSHORE
EARLY IN THE PERIOD...AS THE UPPER TROUGH ADVANCES. IN ITS WAKE...A
LARGE AREA OF HIGH PRESSURE WILL PREVAIL FROM THE PLAINS EWD. A LEE
TROUGH IS FORECAST TO RESIDE ACROSS THE HIGH PLAINS -- SUSTAINED BY
WLY FLOW ACROSS THE ROCKIES -- WHICH WILL BE THE PRIMARY FOCUS FOR
SEVERE CONVECTIVE POTENTIAL -- ALBEIT ISOLATED -- THIS PERIOD.
...CENTRAL AND SRN HIGH PLAINS...
WITH STRONG LARGE-SCALE RIDGING ACROSS THE HIGH PLAINS...RESULTING
SUBSIDENCE WILL MAINTAIN A CAPPING INVERSION ACROSS MOST AREAS
THROUGH THE PERIOD. GREATEST THREAT FOR LOCAL BREACHING OF THE CAP
WILL OCCUR OVER THE HIGH PLAINS...NEAR THE LEE TROUGH. WITH
LOW-LEVEL SELYS BENEATH 25-35 KT MID-LEVEL WLYS...SHEAR WILL SUPPORT
EVOLUTION OF ROTATING UPDRAFTS WITH ANY STORMS WHICH DO DEVELOP.
THUS -- WILL MAINTAIN A ZONE OF 5% SEVERE THREAT...TO ACCOUNT FOR
THE ISOLATED SEVERE POTENTIAL.
..GOSS.. 05/23/2013
000
ACUS02 KWNS 230555
SWODY2
SPC AC 230554
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1254 AM CDT THU MAY 23 2013
VALID 241200Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
AS THE UPPER TROUGH OVER THE ERN U.S. MAKES SLOW EWD PROGRESS THIS
PERIOD...THE UPSTREAM/CENTRAL U.S. RIDGE WILL EXPAND EWD WITH TIME.
MEANWHILE FARTHER W...A LARGE UPPER TROUGH WILL REMAIN IN PLACE OVER
THE WRN STATES THROUGH THE PERIOD.
AT THE SURFACE...EXPECT AN ERN U.S. COLD FRONT TO MOVE OFFSHORE
EARLY IN THE PERIOD...AS THE UPPER TROUGH ADVANCES. IN ITS WAKE...A
LARGE AREA OF HIGH PRESSURE WILL PREVAIL FROM THE PLAINS EWD. A LEE
TROUGH IS FORECAST TO RESIDE ACROSS THE HIGH PLAINS -- SUSTAINED BY
WLY FLOW ACROSS THE ROCKIES -- WHICH WILL BE THE PRIMARY FOCUS FOR
SEVERE CONVECTIVE POTENTIAL -- ALBEIT ISOLATED -- THIS PERIOD.
...CENTRAL AND SRN HIGH PLAINS...
WITH STRONG LARGE-SCALE RIDGING ACROSS THE HIGH PLAINS...RESULTING
SUBSIDENCE WILL MAINTAIN A CAPPING INVERSION ACROSS MOST AREAS
THROUGH THE PERIOD. GREATEST THREAT FOR LOCAL BREACHING OF THE CAP
WILL OCCUR OVER THE HIGH PLAINS...NEAR THE LEE TROUGH. WITH
LOW-LEVEL SELYS BENEATH 25-35 KT MID-LEVEL WLYS...SHEAR WILL SUPPORT
EVOLUTION OF ROTATING UPDRAFTS WITH ANY STORMS WHICH DO DEVELOP.
THUS -- WILL MAINTAIN A ZONE OF 5% SEVERE THREAT...TO ACCOUNT FOR
THE ISOLATED SEVERE POTENTIAL.
..GOSS.. 05/23/2013
000
ACUS01 KWNS 230554
SWODY1
SPC AC 230552
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1252 AM CDT THU MAY 23 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE SRN HIGH
PLAINS...
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE NERN
STATES...
...SYNOPSIS...
BLOCKING UPPER PATTERN WILL PERSIST THURSDAY. UPPER LOW OVER THE
MID-UPPER MS VALLEY WILL ADVANCE THROUGH THE OH VALLEY...WHILE
ANOTHER TROUGH AMPLIFIES SWD INTO THE GREAT LAKES REGION. CLOSED
UPPER LOW OVER THE WRN STATES WILL DRIFT ONLY SLOWLY EWD...WHILE AN
UPPER RIDGE BUILDS ACROSS THE CNTRL STATES. AT THE SFC A COLD FRONT
WILL MOVE THROUGH ERN PORTIONS OF THE OH VALLEY INTO THE ERN STATES.
TRAILING PORTION OF THIS BOUNDARY WILL LIFT NWD THROUGH NRN TX AND
OK...WHILE A DRYLINE BECOMES ESTABLISHED ACROSS WRN TX.
...SRN HIGH PLAINS...
CURRENT INDICATIONS ARE THAT ELEVATED STORMS WILL DEVELOP EARLY
THURSDAY ACROSS NWRN TX INTO SWRN AND CNTRL OK WHERE THE NOCTURNAL
LLJ WILL AUGMENT WARM ADVECTION AND ISENTROPIC ASCENT NORTH OF THE
RETREATING BOUNDARY. RICHER LOW LEVEL MOISTURE WITH 60S DEWPOINTS
WILL ADVECT NWWD THROUGH THE SRN PLAINS WARM SECTOR BENEATH STEEP
LAPSE RATES. STRONG DIABATIC WARMING IS LIKELY SOUTH OF ONGOING
CONVECTION ACROSS NWRN AND WRN TX...WHICH ALONG WITH INCREASING
LOW-LEVEL MOISTURE WILL RESULT IN 2500-3000 J/KG MLCAPE DURING THE
AFTERNOON. STORMS ARE EXPECTED TO DEVELOP BY MID-LATE AFTERNOON IN
VICINITY OF THE DRYLINE/FRONT INTERSECTION OVER NWRN TX...AS WELL AS
SOME DISTANCE SWD INTO THE HIGH PLAINS. RIDGING ALOFT WITH MODEST
UPPER FLOW WILL TEMPER OVERALL SHEAR MAGNITUDES...BUT 30-35 KT
EFFECTIVE SHEAR AND STRONG INSTABILITY WILL BE SUFFICIENT FOR A FEW
SUPERCELLS WITH INITIAL STORMS THAT DEVELOP. PRIMARY THREAT WILL BE
VERY LARGE HAIL. A TORNADO OR TWO MAY ALSO BE POSSIBLE ESPECIALLY
DURING THE EARLY EVENING WHILE STORMS MAY STILL BE DISCRETE AND AS
THE LLJ INCREASES. STORMS MAY EVOLVE INTO AN MCS AND PROPAGATE SEWD
DURING THE EVENING WITH DAMAGING WIND BECOMING THE PRIMARY
THREAT...BEFORE ACTIVITY WEAKENS TOWARD MID-LATE EVENING.
...NERN STATES...
WIDESPREAD MULTILAYER CLOUDS ALONG CONVEYOR BELT WILL LIKELY LIMIT
DIABATIC WARMING AND OVERALL DESTABILIZATION POTENTIAL ACROSS MUCH
OF THE NERN STATES ON THURSDAY. HOWEVER...SOME CLOUD BREAKS WILL
LIKELY OCCUR AND MODEST DIABATIC WARMING OF THE MOIST BOUNDARY LAYER
WILL RESULT IN 500-1000 J/KG MLCAPE. BELT OF 35-40 KT MID-UPPER
LEVEL FLOW ALONG ERN PERIPHERY OF THE UPPER TROUGH WILL EXIST IN
WARM SECTOR RESULTING IN 30-40 KT EFFECTIVE SHEAR. STORMS MAY
UNDERGO A GRADUAL INTENSIFICATION WITH ORGANIZED MULTICELLS CAPABLE
OF PRODUCING MAINLY ISOLATED DAMAGING WIND. ANY SEVERE THREAT SHOULD
DIMINISH BY EARLY EVENING.
..DIAL/GUYER.. 05/23/2013
000
ACUS01 KWNS 230554
SWODY1
SPC AC 230552
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1252 AM CDT THU MAY 23 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE SRN HIGH
PLAINS...
...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE NERN
STATES...
...SYNOPSIS...
BLOCKING UPPER PATTERN WILL PERSIST THURSDAY. UPPER LOW OVER THE
MID-UPPER MS VALLEY WILL ADVANCE THROUGH THE OH VALLEY...WHILE
ANOTHER TROUGH AMPLIFIES SWD INTO THE GREAT LAKES REGION. CLOSED
UPPER LOW OVER THE WRN STATES WILL DRIFT ONLY SLOWLY EWD...WHILE AN
UPPER RIDGE BUILDS ACROSS THE CNTRL STATES. AT THE SFC A COLD FRONT
WILL MOVE THROUGH ERN PORTIONS OF THE OH VALLEY INTO THE ERN STATES.
TRAILING PORTION OF THIS BOUNDARY WILL LIFT NWD THROUGH NRN TX AND
OK...WHILE A DRYLINE BECOMES ESTABLISHED ACROSS WRN TX.
...SRN HIGH PLAINS...
CURRENT INDICATIONS ARE THAT ELEVATED STORMS WILL DEVELOP EARLY
THURSDAY ACROSS NWRN TX INTO SWRN AND CNTRL OK WHERE THE NOCTURNAL
LLJ WILL AUGMENT WARM ADVECTION AND ISENTROPIC ASCENT NORTH OF THE
RETREATING BOUNDARY. RICHER LOW LEVEL MOISTURE WITH 60S DEWPOINTS
WILL ADVECT NWWD THROUGH THE SRN PLAINS WARM SECTOR BENEATH STEEP
LAPSE RATES. STRONG DIABATIC WARMING IS LIKELY SOUTH OF ONGOING
CONVECTION ACROSS NWRN AND WRN TX...WHICH ALONG WITH INCREASING
LOW-LEVEL MOISTURE WILL RESULT IN 2500-3000 J/KG MLCAPE DURING THE
AFTERNOON. STORMS ARE EXPECTED TO DEVELOP BY MID-LATE AFTERNOON IN
VICINITY OF THE DRYLINE/FRONT INTERSECTION OVER NWRN TX...AS WELL AS
SOME DISTANCE SWD INTO THE HIGH PLAINS. RIDGING ALOFT WITH MODEST
UPPER FLOW WILL TEMPER OVERALL SHEAR MAGNITUDES...BUT 30-35 KT
EFFECTIVE SHEAR AND STRONG INSTABILITY WILL BE SUFFICIENT FOR A FEW
SUPERCELLS WITH INITIAL STORMS THAT DEVELOP. PRIMARY THREAT WILL BE
VERY LARGE HAIL. A TORNADO OR TWO MAY ALSO BE POSSIBLE ESPECIALLY
DURING THE EARLY EVENING WHILE STORMS MAY STILL BE DISCRETE AND AS
THE LLJ INCREASES. STORMS MAY EVOLVE INTO AN MCS AND PROPAGATE SEWD
DURING THE EVENING WITH DAMAGING WIND BECOMING THE PRIMARY
THREAT...BEFORE ACTIVITY WEAKENS TOWARD MID-LATE EVENING.
...NERN STATES...
WIDESPREAD MULTILAYER CLOUDS ALONG CONVEYOR BELT WILL LIKELY LIMIT
DIABATIC WARMING AND OVERALL DESTABILIZATION POTENTIAL ACROSS MUCH
OF THE NERN STATES ON THURSDAY. HOWEVER...SOME CLOUD BREAKS WILL
LIKELY OCCUR AND MODEST DIABATIC WARMING OF THE MOIST BOUNDARY LAYER
WILL RESULT IN 500-1000 J/KG MLCAPE. BELT OF 35-40 KT MID-UPPER
LEVEL FLOW ALONG ERN PERIPHERY OF THE UPPER TROUGH WILL EXIST IN
WARM SECTOR RESULTING IN 30-40 KT EFFECTIVE SHEAR. STORMS MAY
UNDERGO A GRADUAL INTENSIFICATION WITH ORGANIZED MULTICELLS CAPABLE
OF PRODUCING MAINLY ISOLATED DAMAGING WIND. ANY SEVERE THREAT SHOULD
DIMINISH BY EARLY EVENING.
..DIAL/GUYER.. 05/23/2013
000
ACUS01 KWNS 230103
SWODY1
SPC AC 230100
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0800 PM CDT WED MAY 22 2013
VALID 230100Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC INTO A
PORTION OF THE NERN STATES...
...MID ATLANTIC THROUGH THE NERN STATES...
ISOLATED STORMS WITH AT LEAST MARGINAL SUPERCELL STRUCTURES ARE
MOVING EWD THROUGH NCNTRL NY. ADDITIONAL STORMS DEVELOPING OVER LAKE
ONTARIO WILL EVENTUALLY MOVE INTO NRN NY. VERTICAL SHEAR IN THIS
REGION IS A BIT STRONGER THAN FARTHER SOUTH WITH 30-40 KT EFFECTIVE
SHEAR...AND THE LLJ IS FORECAST TO STRENGTHEN DURING THE EVENING.
THREAT FOR ISOLATED LARGE HAIL AND DAMAGING WIND WILL PERSIST
THROUGH AT LEAST MID EVENING. ALSO AN ISOLATED TORNADO CANNOT BE
RULED OUT NEXT HOUR OR TWO.
FARTHER SOUTH A BROKEN LINE OF MULTICELL STORMS EXTENDS FROM ERN PA
SWD THROUGH WRN VA AND WRN NC. THIS ACTIVITY MAY CONTINUE TO POSE A
THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL THROUGH MID
EVENING...BUT A GRADUAL DECREASE IS EXPECTED TO BEGIN BY 02Z AS THE
BOUNDARY LAYER BEGINS TO COOL.
...OH VALLEY...
WIDELY SCATTERED MOSTLY MULTICELL STORMS PERSIST ACROSS THE OH
VALLEY SWD INTO THE TN VALLEY WITHIN MODEST BROAD CYCLONIC FLOW
REGIME. A CONVECTIVE OUTFLOW BOUNDARY WAS ALSO OBSERVED FROM SERN KY
THROUGH WRN WV...MOVING WWD. SOME OF THE STORMS MAY BRIEFLY ATTAIN
SEVERE LEVELS NEXT COUPLE HOURS AS THEY INTERACT AND MERGE WITH THE
PREEXISTING OUTFLOW BOUNDARIES. OVERALL COVERAGE OF ANY SEVERE
REPORTS IN THIS REGION IS EXPECTED TO REMAIN SPARSE AND THE ACTIVITY
WILL UNDERGO A GRADUAL DECREASE AS INSTABILITY DIMINISHES WITH ONSET
OF NOCTURNAL COOLING.
..DIAL.. 05/23/2013
000
ACUS01 KWNS 230103
SWODY1
SPC AC 230100
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0800 PM CDT WED MAY 22 2013
VALID 230100Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC INTO A
PORTION OF THE NERN STATES...
...MID ATLANTIC THROUGH THE NERN STATES...
ISOLATED STORMS WITH AT LEAST MARGINAL SUPERCELL STRUCTURES ARE
MOVING EWD THROUGH NCNTRL NY. ADDITIONAL STORMS DEVELOPING OVER LAKE
ONTARIO WILL EVENTUALLY MOVE INTO NRN NY. VERTICAL SHEAR IN THIS
REGION IS A BIT STRONGER THAN FARTHER SOUTH WITH 30-40 KT EFFECTIVE
SHEAR...AND THE LLJ IS FORECAST TO STRENGTHEN DURING THE EVENING.
THREAT FOR ISOLATED LARGE HAIL AND DAMAGING WIND WILL PERSIST
THROUGH AT LEAST MID EVENING. ALSO AN ISOLATED TORNADO CANNOT BE
RULED OUT NEXT HOUR OR TWO.
FARTHER SOUTH A BROKEN LINE OF MULTICELL STORMS EXTENDS FROM ERN PA
SWD THROUGH WRN VA AND WRN NC. THIS ACTIVITY MAY CONTINUE TO POSE A
THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL THROUGH MID
EVENING...BUT A GRADUAL DECREASE IS EXPECTED TO BEGIN BY 02Z AS THE
BOUNDARY LAYER BEGINS TO COOL.
...OH VALLEY...
WIDELY SCATTERED MOSTLY MULTICELL STORMS PERSIST ACROSS THE OH
VALLEY SWD INTO THE TN VALLEY WITHIN MODEST BROAD CYCLONIC FLOW
REGIME. A CONVECTIVE OUTFLOW BOUNDARY WAS ALSO OBSERVED FROM SERN KY
THROUGH WRN WV...MOVING WWD. SOME OF THE STORMS MAY BRIEFLY ATTAIN
SEVERE LEVELS NEXT COUPLE HOURS AS THEY INTERACT AND MERGE WITH THE
PREEXISTING OUTFLOW BOUNDARIES. OVERALL COVERAGE OF ANY SEVERE
REPORTS IN THIS REGION IS EXPECTED TO REMAIN SPARSE AND THE ACTIVITY
WILL UNDERGO A GRADUAL DECREASE AS INSTABILITY DIMINISHES WITH ONSET
OF NOCTURNAL COOLING.
..DIAL.. 05/23/2013
000
ACUS11 KWNS 230022
SWOMCD
SPC MCD 230021
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-230115-
MESOSCALE DISCUSSION 0775
NWS STORM PREDICTION CENTER NORMAN OK
0721 PM CDT WED MAY 22 2013
AREAS AFFECTED...WV...SE OH...WRN PA
CONCERNING...SEVERE THUNDERSTORM WATCH 211...
VALID 230021Z - 230115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 211
CONTINUES.
SUMMARY...AN ISOLATED SEVERE THREAT WILL LIKELY CONTINUE ACROSS WW
211 FOR THE NEXT FEW HOURS. THE STRONGEST CELLS COULD HAVE A
MARGINAL THREAT FOR WIND DAMAGE AND HAIL. DUE TO THE MARGINAL NATURE
OF THE THREAT...WW ISSUANCE IS NOT EXPECTED BEYOND THE 02Z WATCH
EXPIRATION.
DISCUSSION...LATEST SFC ANALYSIS SHOWS A SFC LOW NORTH OF LAKE ERIE
WITH SOUTH TO SOUTHWEST FLOW LOCATED ACROSS ERN OH AND WRN PA. SWD
ACROSS WV...AN OUTFLOW BOUNDARY APPEARS TO BE MOVING WWD TOWARD THE
OH RIVER WHERE NEW CELLS HAVE INITIATED IN THE LAST HOUR. THIS
CONVECTION COULD EXPAND IN COVERAGE AS LARGE-SCALE ASCENT INCREASES
EARLY THIS EVENING DUE TO A DISTURBANCE MOVING EWD THROUGH THE OH
VALLEY EVIDENT ON WATER VAPOR IMAGERY. THE STORMS SHOULD MOVE NEWD
INTO ERN OH WHERE OBJECTIVE ANALYSIS CURRENTLY SHOWS MLCAPE VALUES
OF 750 TO 1000 J/KG AND 30-35 KT OF 0-6 KM SHEAR. THIS ALONG WITH
0-3 KM LAPSE RATES AROUND 7.5 C/KM COULD SUPPORT AN ISOLATED WIND
DAMAGE THREAT. THE THREAT SHOULD REMAIN MARGINAL DUE TO WEAKENING
INSTABILITY AND WW 211 WILL BE ALLOWED TO EXPIRE ON SCHEDULE.
..BROYLES/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS11 KWNS 230022
SWOMCD
SPC MCD 230021
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-230115-
MESOSCALE DISCUSSION 0775
NWS STORM PREDICTION CENTER NORMAN OK
0721 PM CDT WED MAY 22 2013
AREAS AFFECTED...WV...SE OH...WRN PA
CONCERNING...SEVERE THUNDERSTORM WATCH 211...
VALID 230021Z - 230115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 211
CONTINUES.
SUMMARY...AN ISOLATED SEVERE THREAT WILL LIKELY CONTINUE ACROSS WW
211 FOR THE NEXT FEW HOURS. THE STRONGEST CELLS COULD HAVE A
MARGINAL THREAT FOR WIND DAMAGE AND HAIL. DUE TO THE MARGINAL NATURE
OF THE THREAT...WW ISSUANCE IS NOT EXPECTED BEYOND THE 02Z WATCH
EXPIRATION.
DISCUSSION...LATEST SFC ANALYSIS SHOWS A SFC LOW NORTH OF LAKE ERIE
WITH SOUTH TO SOUTHWEST FLOW LOCATED ACROSS ERN OH AND WRN PA. SWD
ACROSS WV...AN OUTFLOW BOUNDARY APPEARS TO BE MOVING WWD TOWARD THE
OH RIVER WHERE NEW CELLS HAVE INITIATED IN THE LAST HOUR. THIS
CONVECTION COULD EXPAND IN COVERAGE AS LARGE-SCALE ASCENT INCREASES
EARLY THIS EVENING DUE TO A DISTURBANCE MOVING EWD THROUGH THE OH
VALLEY EVIDENT ON WATER VAPOR IMAGERY. THE STORMS SHOULD MOVE NEWD
INTO ERN OH WHERE OBJECTIVE ANALYSIS CURRENTLY SHOWS MLCAPE VALUES
OF 750 TO 1000 J/KG AND 30-35 KT OF 0-6 KM SHEAR. THIS ALONG WITH
0-3 KM LAPSE RATES AROUND 7.5 C/KM COULD SUPPORT AN ISOLATED WIND
DAMAGE THREAT. THE THREAT SHOULD REMAIN MARGINAL DUE TO WEAKENING
INSTABILITY AND WW 211 WILL BE ALLOWED TO EXPIRE ON SCHEDULE.
..BROYLES/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS11 KWNS 230022
SWOMCD
SPC MCD 230021
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-230115-
MESOSCALE DISCUSSION 0775
NWS STORM PREDICTION CENTER NORMAN OK
0721 PM CDT WED MAY 22 2013
AREAS AFFECTED...WV...SE OH...WRN PA
CONCERNING...SEVERE THUNDERSTORM WATCH 211...
VALID 230021Z - 230115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 211
CONTINUES.
SUMMARY...AN ISOLATED SEVERE THREAT WILL LIKELY CONTINUE ACROSS WW
211 FOR THE NEXT FEW HOURS. THE STRONGEST CELLS COULD HAVE A
MARGINAL THREAT FOR WIND DAMAGE AND HAIL. DUE TO THE MARGINAL NATURE
OF THE THREAT...WW ISSUANCE IS NOT EXPECTED BEYOND THE 02Z WATCH
EXPIRATION.
DISCUSSION...LATEST SFC ANALYSIS SHOWS A SFC LOW NORTH OF LAKE ERIE
WITH SOUTH TO SOUTHWEST FLOW LOCATED ACROSS ERN OH AND WRN PA. SWD
ACROSS WV...AN OUTFLOW BOUNDARY APPEARS TO BE MOVING WWD TOWARD THE
OH RIVER WHERE NEW CELLS HAVE INITIATED IN THE LAST HOUR. THIS
CONVECTION COULD EXPAND IN COVERAGE AS LARGE-SCALE ASCENT INCREASES
EARLY THIS EVENING DUE TO A DISTURBANCE MOVING EWD THROUGH THE OH
VALLEY EVIDENT ON WATER VAPOR IMAGERY. THE STORMS SHOULD MOVE NEWD
INTO ERN OH WHERE OBJECTIVE ANALYSIS CURRENTLY SHOWS MLCAPE VALUES
OF 750 TO 1000 J/KG AND 30-35 KT OF 0-6 KM SHEAR. THIS ALONG WITH
0-3 KM LAPSE RATES AROUND 7.5 C/KM COULD SUPPORT AN ISOLATED WIND
DAMAGE THREAT. THE THREAT SHOULD REMAIN MARGINAL DUE TO WEAKENING
INSTABILITY AND WW 211 WILL BE ALLOWED TO EXPIRE ON SCHEDULE.
..BROYLES/THOMPSON.. 05/23/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS11 KWNS 222342
SWOMCD
SPC MCD 222341
VTZ000-CTZ000-MAZ000-NYZ000-PAZ000-230115-
MESOSCALE DISCUSSION 0774
NWS STORM PREDICTION CENTER NORMAN OK
0641 PM CDT WED MAY 22 2013
AREAS AFFECTED...MUCH OF UPSTATE NY/NORTHEAST PA INTO WESTERN
PORTIONS OF NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 210...212...
VALID 222341Z - 230115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
210...212...CONTINUES.
SUMMARY...SEVERE HAIL/DAMAGING WIND POTENTIAL CONTINUES WITHIN
SEVERE TSTM WATCHES 210/212...BUT ON AN INCREASINGLY
MARGINAL/ISOLATED BASIS INTO THIS EVENING. SOME TORNADO THREAT MAY
ALSO BE POSSIBLE IN THE SHORT-TERM ACROSS NORTH-CENTRAL/EAST-CENTRAL
NY.
DISCUSSION...AS OF 2330Z...A SUPERCELL IS NOTED ACROSS ONEIDA COUNTY
NY NORTHWEST OF THE ROME AREA. THE STORM MAY BE THRIVING ON WESTERN
PERIPHERY OF MODIFYING OUTFLOW FROM EARLIER. ASIDE FROM SEVERE
HAIL...SOME TORNADO THREAT...ALBEIT LIKELY BRIEF...CANNOT BE RULED
OUT AS THE STORM CONTINUES TO SEEMINGLY INTERACT WITH THE INFLUENCE
OF THE BOUNDARY...PRIOR TO ENCOUNTERING COOLER/MORE STABLE LOW-LEVEL
INFLOW. IN THE SHORT TERM...BACKED EAST-SOUTHEASTERLY LOW-LEVEL
WINDS ARE NOTED AT KRME WITH ESTIMATES OF 100+ 0-1 KM SRH BASED ON
REGIONAL WSR-88D VWP DATA.
A DAMAGING WIND/ISOLATED SEVERE HAIL WILL LIKELY CONTINUE OVER THE
NEXT HOUR OR TWO ACROSS NORTHEAST PA/PERHAPS FAR SOUTHERN NY IN
ASSOCIATED WITH A SEMI-ORGANIZED LINEAR SYSTEM/ASSOCIATED COLD POOL.
OTHERWISE...A CONVECTIVELY OVERTURNED AND/OR NOCTURNALLY COOLING
BOUNDARY LAYER WILL LIKELY LEAD TO A DIMINISHING SEVERE RISK THE
REMAINDER OF THIS EVENING...FOR ONE PARTS OF FAR EASTERN NY INTO NEW
ENGLAND.
..GUYER.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 42137770 42937709 43677577 43937290 41997313 41227506
40987612 41507718 42137770
000
ACUS11 KWNS 222342
SWOMCD
SPC MCD 222341
VTZ000-CTZ000-MAZ000-NYZ000-PAZ000-230115-
MESOSCALE DISCUSSION 0774
NWS STORM PREDICTION CENTER NORMAN OK
0641 PM CDT WED MAY 22 2013
AREAS AFFECTED...MUCH OF UPSTATE NY/NORTHEAST PA INTO WESTERN
PORTIONS OF NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 210...212...
VALID 222341Z - 230115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
210...212...CONTINUES.
SUMMARY...SEVERE HAIL/DAMAGING WIND POTENTIAL CONTINUES WITHIN
SEVERE TSTM WATCHES 210/212...BUT ON AN INCREASINGLY
MARGINAL/ISOLATED BASIS INTO THIS EVENING. SOME TORNADO THREAT MAY
ALSO BE POSSIBLE IN THE SHORT-TERM ACROSS NORTH-CENTRAL/EAST-CENTRAL
NY.
DISCUSSION...AS OF 2330Z...A SUPERCELL IS NOTED ACROSS ONEIDA COUNTY
NY NORTHWEST OF THE ROME AREA. THE STORM MAY BE THRIVING ON WESTERN
PERIPHERY OF MODIFYING OUTFLOW FROM EARLIER. ASIDE FROM SEVERE
HAIL...SOME TORNADO THREAT...ALBEIT LIKELY BRIEF...CANNOT BE RULED
OUT AS THE STORM CONTINUES TO SEEMINGLY INTERACT WITH THE INFLUENCE
OF THE BOUNDARY...PRIOR TO ENCOUNTERING COOLER/MORE STABLE LOW-LEVEL
INFLOW. IN THE SHORT TERM...BACKED EAST-SOUTHEASTERLY LOW-LEVEL
WINDS ARE NOTED AT KRME WITH ESTIMATES OF 100+ 0-1 KM SRH BASED ON
REGIONAL WSR-88D VWP DATA.
A DAMAGING WIND/ISOLATED SEVERE HAIL WILL LIKELY CONTINUE OVER THE
NEXT HOUR OR TWO ACROSS NORTHEAST PA/PERHAPS FAR SOUTHERN NY IN
ASSOCIATED WITH A SEMI-ORGANIZED LINEAR SYSTEM/ASSOCIATED COLD POOL.
OTHERWISE...A CONVECTIVELY OVERTURNED AND/OR NOCTURNALLY COOLING
BOUNDARY LAYER WILL LIKELY LEAD TO A DIMINISHING SEVERE RISK THE
REMAINDER OF THIS EVENING...FOR ONE PARTS OF FAR EASTERN NY INTO NEW
ENGLAND.
..GUYER.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 42137770 42937709 43677577 43937290 41997313 41227506
40987612 41507718 42137770
000
ACUS11 KWNS 222221
SWOMCD
SPC MCD 222220
PAZ000-MDZ000-VAZ000-WVZ000-222345-
MESOSCALE DISCUSSION 0773
NWS STORM PREDICTION CENTER NORMAN OK
0520 PM CDT WED MAY 22 2013
AREAS AFFECTED...CENTRAL PA...NRN MD...NE WV PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 222220Z - 222345Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...MARGINAL HAIL/WIND RISK WILL CONTINUE FOR ANOTHER COUPLE
OF HOURS. AN EWD EXTENSION OF WW 211 COULD BE CONSIDERED...BUT A
NEW WW DOES NOT APPEAR NECESSARY.
DISCUSSION...SCATTERED STRONG/MARGINALLY SEVERE STORMS HAVE FORMED
NEAR THE E EDGE OF THE HIGHER TERRAIN...ALONG A LOOSELY
ORGANIZED/WEAK OUTFLOW MOVING NEWD ACROSS THE NE WV PANHANDLE/WRN MD
PANHANDLE INTO S CENTRAL PA. SOMEWHAT GREATER LOW-LEVEL MOISTURE IS
OBSERVED ACROSS THE LOWER TERRAIN FROM NRN VA/NRN MD INTO SE
PA...WITH CORRESPONDINGLY LARGER BUOYANCY. HOWEVER...VERTICAL SHEAR
BECOMES QUITE WEAK WITH EWD EXTENT...AND PRIMARILY SHORT-LIVED
MULTICELL CLUSTERS SHOULD BE THE DOMINANT CONVECTIVE MODE. GIVEN
MODEST BUOYANCY AND WEAK VERTICAL SHEAR...A FEW DOWNBURSTS AND
MARGINALLY SEVERE HAIL WILL BE THE MAIN CONCERNS PRIOR TO
STABILIZATION OF THE BOUNDARY LAYER WITH THE LOSS OF DAYTIME HEATING
IN THE NEXT FEW HOURS.
..THOMPSON.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...
LAT...LON 39507711 39157755 39167799 39587795 40257790 40957808
41407772 41587713 41527657 41147640 40307681 39507711
000
ACUS11 KWNS 222221
SWOMCD
SPC MCD 222220
PAZ000-MDZ000-VAZ000-WVZ000-222345-
MESOSCALE DISCUSSION 0773
NWS STORM PREDICTION CENTER NORMAN OK
0520 PM CDT WED MAY 22 2013
AREAS AFFECTED...CENTRAL PA...NRN MD...NE WV PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 222220Z - 222345Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...MARGINAL HAIL/WIND RISK WILL CONTINUE FOR ANOTHER COUPLE
OF HOURS. AN EWD EXTENSION OF WW 211 COULD BE CONSIDERED...BUT A
NEW WW DOES NOT APPEAR NECESSARY.
DISCUSSION...SCATTERED STRONG/MARGINALLY SEVERE STORMS HAVE FORMED
NEAR THE E EDGE OF THE HIGHER TERRAIN...ALONG A LOOSELY
ORGANIZED/WEAK OUTFLOW MOVING NEWD ACROSS THE NE WV PANHANDLE/WRN MD
PANHANDLE INTO S CENTRAL PA. SOMEWHAT GREATER LOW-LEVEL MOISTURE IS
OBSERVED ACROSS THE LOWER TERRAIN FROM NRN VA/NRN MD INTO SE
PA...WITH CORRESPONDINGLY LARGER BUOYANCY. HOWEVER...VERTICAL SHEAR
BECOMES QUITE WEAK WITH EWD EXTENT...AND PRIMARILY SHORT-LIVED
MULTICELL CLUSTERS SHOULD BE THE DOMINANT CONVECTIVE MODE. GIVEN
MODEST BUOYANCY AND WEAK VERTICAL SHEAR...A FEW DOWNBURSTS AND
MARGINALLY SEVERE HAIL WILL BE THE MAIN CONCERNS PRIOR TO
STABILIZATION OF THE BOUNDARY LAYER WITH THE LOSS OF DAYTIME HEATING
IN THE NEXT FEW HOURS.
..THOMPSON.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...
LAT...LON 39507711 39157755 39167799 39587795 40257790 40957808
41407772 41587713 41527657 41147640 40307681 39507711
000
ACUS11 KWNS 222221
SWOMCD
SPC MCD 222220
PAZ000-MDZ000-VAZ000-WVZ000-222345-
MESOSCALE DISCUSSION 0773
NWS STORM PREDICTION CENTER NORMAN OK
0520 PM CDT WED MAY 22 2013
AREAS AFFECTED...CENTRAL PA...NRN MD...NE WV PANHANDLE
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 222220Z - 222345Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...MARGINAL HAIL/WIND RISK WILL CONTINUE FOR ANOTHER COUPLE
OF HOURS. AN EWD EXTENSION OF WW 211 COULD BE CONSIDERED...BUT A
NEW WW DOES NOT APPEAR NECESSARY.
DISCUSSION...SCATTERED STRONG/MARGINALLY SEVERE STORMS HAVE FORMED
NEAR THE E EDGE OF THE HIGHER TERRAIN...ALONG A LOOSELY
ORGANIZED/WEAK OUTFLOW MOVING NEWD ACROSS THE NE WV PANHANDLE/WRN MD
PANHANDLE INTO S CENTRAL PA. SOMEWHAT GREATER LOW-LEVEL MOISTURE IS
OBSERVED ACROSS THE LOWER TERRAIN FROM NRN VA/NRN MD INTO SE
PA...WITH CORRESPONDINGLY LARGER BUOYANCY. HOWEVER...VERTICAL SHEAR
BECOMES QUITE WEAK WITH EWD EXTENT...AND PRIMARILY SHORT-LIVED
MULTICELL CLUSTERS SHOULD BE THE DOMINANT CONVECTIVE MODE. GIVEN
MODEST BUOYANCY AND WEAK VERTICAL SHEAR...A FEW DOWNBURSTS AND
MARGINALLY SEVERE HAIL WILL BE THE MAIN CONCERNS PRIOR TO
STABILIZATION OF THE BOUNDARY LAYER WITH THE LOSS OF DAYTIME HEATING
IN THE NEXT FEW HOURS.
..THOMPSON.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...CTP...LWX...
LAT...LON 39507711 39157755 39167799 39587795 40257790 40957808
41407772 41587713 41527657 41147640 40307681 39507711
000
ACUS11 KWNS 222029
SWOMCD
SPC MCD 222028
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-222200-
MESOSCALE DISCUSSION 0772
NWS STORM PREDICTION CENTER NORMAN OK
0328 PM CDT WED MAY 22 2013
AREAS AFFECTED...ERN NY INTO SRN NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 210...
VALID 222028Z - 222200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 210
CONTINUES.
SUMMARY...WHILE THE THREAT FOR SEVERE WEATHER HAS LESSENED
RECENTLY...OTHER STORMS MAY AFFECT THE AREA LATER TODAY...MAINLY NRN
NY INTO CNTRL AND WRN NY.
DISCUSSION...INITIAL ROUND OF THUNDERSTORMS IS IN THE PROCESS OF
WEAKENING E OF THE ALBANY AREA...BUT ISOLATED STRONG CORES STILL
EXIST OVER FAR SRN NY AND ACROSS FAR NRN NY WITH HAIL THREAT. WHILE
THE AIR MASS HAS TEMPORARILY STABILIZED...SLY LOW LEVEL FLOW MAY
ALLOW FOR CAPE TO RETURN LATER TODAY. CELLS E OF LAKE ONTARIO MAY
PERSIST INTO CNTRL NY...AND MORE DEVELOPMENT IS EXPECTED LATER THIS
EVENING ESPECIALLY ACROSS WRN PORTIONS OF WW 210.
..JEWELL.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS11 KWNS 222029
SWOMCD
SPC MCD 222028
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-222200-
MESOSCALE DISCUSSION 0772
NWS STORM PREDICTION CENTER NORMAN OK
0328 PM CDT WED MAY 22 2013
AREAS AFFECTED...ERN NY INTO SRN NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 210...
VALID 222028Z - 222200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 210
CONTINUES.
SUMMARY...WHILE THE THREAT FOR SEVERE WEATHER HAS LESSENED
RECENTLY...OTHER STORMS MAY AFFECT THE AREA LATER TODAY...MAINLY NRN
NY INTO CNTRL AND WRN NY.
DISCUSSION...INITIAL ROUND OF THUNDERSTORMS IS IN THE PROCESS OF
WEAKENING E OF THE ALBANY AREA...BUT ISOLATED STRONG CORES STILL
EXIST OVER FAR SRN NY AND ACROSS FAR NRN NY WITH HAIL THREAT. WHILE
THE AIR MASS HAS TEMPORARILY STABILIZED...SLY LOW LEVEL FLOW MAY
ALLOW FOR CAPE TO RETURN LATER TODAY. CELLS E OF LAKE ONTARIO MAY
PERSIST INTO CNTRL NY...AND MORE DEVELOPMENT IS EXPECTED LATER THIS
EVENING ESPECIALLY ACROSS WRN PORTIONS OF WW 210.
..JEWELL.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS11 KWNS 222029
SWOMCD
SPC MCD 222028
NHZ000-VTZ000-MAZ000-CTZ000-NYZ000-PAZ000-222200-
MESOSCALE DISCUSSION 0772
NWS STORM PREDICTION CENTER NORMAN OK
0328 PM CDT WED MAY 22 2013
AREAS AFFECTED...ERN NY INTO SRN NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 210...
VALID 222028Z - 222200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 210
CONTINUES.
SUMMARY...WHILE THE THREAT FOR SEVERE WEATHER HAS LESSENED
RECENTLY...OTHER STORMS MAY AFFECT THE AREA LATER TODAY...MAINLY NRN
NY INTO CNTRL AND WRN NY.
DISCUSSION...INITIAL ROUND OF THUNDERSTORMS IS IN THE PROCESS OF
WEAKENING E OF THE ALBANY AREA...BUT ISOLATED STRONG CORES STILL
EXIST OVER FAR SRN NY AND ACROSS FAR NRN NY WITH HAIL THREAT. WHILE
THE AIR MASS HAS TEMPORARILY STABILIZED...SLY LOW LEVEL FLOW MAY
ALLOW FOR CAPE TO RETURN LATER TODAY. CELLS E OF LAKE ONTARIO MAY
PERSIST INTO CNTRL NY...AND MORE DEVELOPMENT IS EXPECTED LATER THIS
EVENING ESPECIALLY ACROSS WRN PORTIONS OF WW 210.
..JEWELL.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...BUF...CTP...
LAT...LON 45027129 41417320 41407665 45027498 45027129
000
ACUS01 KWNS 222000
SWODY1
SPC AC 221958
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT WED MAY 22 2013
VALID 222000Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE APPALACHIANS INTO THE
LOWER GREAT LAKES AND NEW ENGLAND...
...APPALACHIANS INTO LOWER GREAT LAKES AND NEW ENGLAND...
UNSTABLE AIR MASS IS LOCATED ACROSS THIS REGION IN ADVANCE OF THE
UPPER LOW APPROACHING THE MIDDLE MS VALLEY AND SHORT WAVE TROUGH
MOVING INTO THE LOWER OH/TN VALLEYS. STRONGER HEATING AND
DESTABILIZATION HAS OCCURRED FROM THE CENTRAL APPALACHIANS INTO THE
LOWER GREAT LAKES AREA...AND STRONG OCCASIONALLY SEVERE STORMS HAVE
DEVELOPED FROM SWRN PA SWD ALONG THE CREST OF APPALACHIANS. AS THE
CAP CONTINUES TO WEAKEN FROM WRN PA INTO WRN/CENTRAL NY...SCATTERED
STORMS ARE EXPECTED TO DEVELOP NEWD THROUGH THE EVENING HOURS.
MODERATELY STRONG SWLY FLOW ALOFT /30-40 KT/ WILL PROVIDE SUFFICIENT
VERTICAL SHEAR FOR ORGANIZED STORMS TO DEVELOP WITH POTENTIAL FOR
STRONGER CELLS TO PRODUCE DAMAGING WIND GUSTS AND HAIL. ACTIVITY IS
LIKELY TO SPREAD NEWD THROUGH 03-06Z BEFORE WEAKENING LATER TONIGHT.
FARTHER WEST OVER PARTS OF THE WRN OH AND TN VALLEYS...WIDESPREAD
CLOUDS HAVE INHIBITED HEATING/SUBSTANTIAL DESTABILIZATION AND THE
SEVERE THREAT OVER THESE AREAS APPEARS TO HAVE DIMINISHED.
..WEISS.. 05/22/2013
.PREV DISCUSSION... /ISSUED 1110 AM CDT WED MAY 22 2013/
...SYNOPSIS...
THE PROMINENT BLOCKING PATTERN NOW PRESENT ACROSS MUCH OF WESTERN
AND CENTRAL NORTH AMERICA MAY BEGIN TO WEAKEN DURING THIS FORECAST
PERIOD. AS A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG
SOUTHEAST OF THE HUDSON BAY REGION...THE CLOSED LOW OVER THE UPPER
MISSISSIPPI VALLEY APPEARS LIKELY TO TRANSITION TO AN OPEN WAVE AND
SHIFT EASTWARD INTO THE OHIO VALLEY. A SMALLER SCALE IMPULSE
CURRENTLY PIVOTING AROUND THE SOUTHERN/EASTERN PERIPHERY OF THIS
REMNANT CYCLONIC CIRCULATION IS EXPECTED TO SHIFT NORTHEASTWARD
TOWARD THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION THROUGH
LATE AFTERNOON...BEFORE WEAKENING AND BECOMING INCREASINGLY SHEARED
WITHIN A CONFLUENT REGIME INTO THE CANADIAN MARITIMES.
AT THE SAME TIME...HOWEVER...LITTLE MOVEMENT IS EXPECTED WITH A
LARGE AND COLD MID/UPPER LOW NOW CENTERED OVER THE NORTHERN PACIFIC
COAST STATES. WHILE SOME DEVIATION OF THE CIRCULATION CENTER IS
LIKELY...THIS WILL MOSTLY BE IN RESPONSE TO SHORT WAVE IMPULSES
ROTATING AROUND ITS PERIPHERY.
...OH/TN VALLEYS INTO THE LOWER GREAT LAKES AND NEW ENGLAND...
EXTENSIVE CONVECTION AND ASSOCIATED OUTFLOW FROM YESTERDAY HAS
IMPACTED A SIGNIFICANT PORTION OF THE WARM SECTOR OF THE SURFACE LOW
NOW CENTERED OVER THE UPPER MIDWEST...FROM THE MISSISSIPPI VALLEY
EASTWARD TO THE APPALACHIANS. AND THE FOCUS FOR STORM DEVELOPMENT
LATER THIS AFTERNOON AND EVENING REMAINS A BIT UNCLEAR.
HOWEVER...MODELS CONTINUE TO SUGGEST STRENGTHENING OF LOWER/MID
TROPOSPHERIC FLOW FIELDS /TO AROUND 40 KTS OR SO/ IN A SOUTHERLY
BELT ACROSS PARTS OF THE UPPER OHIO VALLEY INTO THE LEE OF THE LOWER
GREAT LAKES BY LATE THIS AFTERNOON...WHICH SHOULD ENHANCE ANY STORM
DEVELOPMENT OCCURRING IN THE PEAK HEATING.
SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORM DEVELOPMENT...WHICH MAY
EVENTUALLY CONSOLIDATE INTO CLUSTERS OR LINES WITH AN ENHANCED RISK
FOR DAMAGING WIND GUSTS. BUT DISCRETE STORM DEVELOPMENT ALSO WILL
BE POSSIBLE...PARTICULARLY NEAR THE CREST OF BROADER SCALE UPPER
RIDGING ACROSS UPSTATE NEW YORK...WHERE MID/UPPER FLOW WILL BE
SLOWER TO BACK TO A SOUTHERLY DIRECTION. MID-LEVEL LAPSE RATES
APPEAR TO HAVE STABILIZED SOME OVER THE PAST DAY OR SO...BUT SEVERE
HAIL STILL SEEMS POSSIBLE...ALONG WITH A RISK FOR ONE OR TWO
TORNADOES...BEFORE STORMS WEAKEN BY LATE EVENING.
...NORTHERN ROCKIES...
MOISTURE APPEARS MARGINAL FOR VIGOROUS STORM DEVELOPMENT...BUT
STRONGER HEATING ALONG AN AXIS FROM NORTHEAST WYOMING THROUGH
WESTERN MONTANA MAY CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR
SCATTERED STORM DEVELOPMENT THIS AFTERNOON. OROGRAPHIC LIFT WILL BE
AIDED BY LARGE-SCALE ASCENT BENEATH STRONGLY DIFLUENT AND DIVERGENT
UPPER FLOW. GIVEN THE FAVORABLE SHEAR BENEATH STRONG CYCLONIC
MID/UPPER FLOW...IT DOES NOT APPEAR COMPLETELY OUT OF THE QUESTION
THAT INSTABILITY ON A VERY LOCALIZED BASIS COULD BECOME ENOUGH FOR A
SUPERCELL OR TWO WITH THE RISK FOR SEVERE HAIL OR WIND.
000
ACUS01 KWNS 222000
SWODY1
SPC AC 221958
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT WED MAY 22 2013
VALID 222000Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE APPALACHIANS INTO THE
LOWER GREAT LAKES AND NEW ENGLAND...
...APPALACHIANS INTO LOWER GREAT LAKES AND NEW ENGLAND...
UNSTABLE AIR MASS IS LOCATED ACROSS THIS REGION IN ADVANCE OF THE
UPPER LOW APPROACHING THE MIDDLE MS VALLEY AND SHORT WAVE TROUGH
MOVING INTO THE LOWER OH/TN VALLEYS. STRONGER HEATING AND
DESTABILIZATION HAS OCCURRED FROM THE CENTRAL APPALACHIANS INTO THE
LOWER GREAT LAKES AREA...AND STRONG OCCASIONALLY SEVERE STORMS HAVE
DEVELOPED FROM SWRN PA SWD ALONG THE CREST OF APPALACHIANS. AS THE
CAP CONTINUES TO WEAKEN FROM WRN PA INTO WRN/CENTRAL NY...SCATTERED
STORMS ARE EXPECTED TO DEVELOP NEWD THROUGH THE EVENING HOURS.
MODERATELY STRONG SWLY FLOW ALOFT /30-40 KT/ WILL PROVIDE SUFFICIENT
VERTICAL SHEAR FOR ORGANIZED STORMS TO DEVELOP WITH POTENTIAL FOR
STRONGER CELLS TO PRODUCE DAMAGING WIND GUSTS AND HAIL. ACTIVITY IS
LIKELY TO SPREAD NEWD THROUGH 03-06Z BEFORE WEAKENING LATER TONIGHT.
FARTHER WEST OVER PARTS OF THE WRN OH AND TN VALLEYS...WIDESPREAD
CLOUDS HAVE INHIBITED HEATING/SUBSTANTIAL DESTABILIZATION AND THE
SEVERE THREAT OVER THESE AREAS APPEARS TO HAVE DIMINISHED.
..WEISS.. 05/22/2013
.PREV DISCUSSION... /ISSUED 1110 AM CDT WED MAY 22 2013/
...SYNOPSIS...
THE PROMINENT BLOCKING PATTERN NOW PRESENT ACROSS MUCH OF WESTERN
AND CENTRAL NORTH AMERICA MAY BEGIN TO WEAKEN DURING THIS FORECAST
PERIOD. AS A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG
SOUTHEAST OF THE HUDSON BAY REGION...THE CLOSED LOW OVER THE UPPER
MISSISSIPPI VALLEY APPEARS LIKELY TO TRANSITION TO AN OPEN WAVE AND
SHIFT EASTWARD INTO THE OHIO VALLEY. A SMALLER SCALE IMPULSE
CURRENTLY PIVOTING AROUND THE SOUTHERN/EASTERN PERIPHERY OF THIS
REMNANT CYCLONIC CIRCULATION IS EXPECTED TO SHIFT NORTHEASTWARD
TOWARD THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION THROUGH
LATE AFTERNOON...BEFORE WEAKENING AND BECOMING INCREASINGLY SHEARED
WITHIN A CONFLUENT REGIME INTO THE CANADIAN MARITIMES.
AT THE SAME TIME...HOWEVER...LITTLE MOVEMENT IS EXPECTED WITH A
LARGE AND COLD MID/UPPER LOW NOW CENTERED OVER THE NORTHERN PACIFIC
COAST STATES. WHILE SOME DEVIATION OF THE CIRCULATION CENTER IS
LIKELY...THIS WILL MOSTLY BE IN RESPONSE TO SHORT WAVE IMPULSES
ROTATING AROUND ITS PERIPHERY.
...OH/TN VALLEYS INTO THE LOWER GREAT LAKES AND NEW ENGLAND...
EXTENSIVE CONVECTION AND ASSOCIATED OUTFLOW FROM YESTERDAY HAS
IMPACTED A SIGNIFICANT PORTION OF THE WARM SECTOR OF THE SURFACE LOW
NOW CENTERED OVER THE UPPER MIDWEST...FROM THE MISSISSIPPI VALLEY
EASTWARD TO THE APPALACHIANS. AND THE FOCUS FOR STORM DEVELOPMENT
LATER THIS AFTERNOON AND EVENING REMAINS A BIT UNCLEAR.
HOWEVER...MODELS CONTINUE TO SUGGEST STRENGTHENING OF LOWER/MID
TROPOSPHERIC FLOW FIELDS /TO AROUND 40 KTS OR SO/ IN A SOUTHERLY
BELT ACROSS PARTS OF THE UPPER OHIO VALLEY INTO THE LEE OF THE LOWER
GREAT LAKES BY LATE THIS AFTERNOON...WHICH SHOULD ENHANCE ANY STORM
DEVELOPMENT OCCURRING IN THE PEAK HEATING.
SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORM DEVELOPMENT...WHICH MAY
EVENTUALLY CONSOLIDATE INTO CLUSTERS OR LINES WITH AN ENHANCED RISK
FOR DAMAGING WIND GUSTS. BUT DISCRETE STORM DEVELOPMENT ALSO WILL
BE POSSIBLE...PARTICULARLY NEAR THE CREST OF BROADER SCALE UPPER
RIDGING ACROSS UPSTATE NEW YORK...WHERE MID/UPPER FLOW WILL BE
SLOWER TO BACK TO A SOUTHERLY DIRECTION. MID-LEVEL LAPSE RATES
APPEAR TO HAVE STABILIZED SOME OVER THE PAST DAY OR SO...BUT SEVERE
HAIL STILL SEEMS POSSIBLE...ALONG WITH A RISK FOR ONE OR TWO
TORNADOES...BEFORE STORMS WEAKEN BY LATE EVENING.
...NORTHERN ROCKIES...
MOISTURE APPEARS MARGINAL FOR VIGOROUS STORM DEVELOPMENT...BUT
STRONGER HEATING ALONG AN AXIS FROM NORTHEAST WYOMING THROUGH
WESTERN MONTANA MAY CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR
SCATTERED STORM DEVELOPMENT THIS AFTERNOON. OROGRAPHIC LIFT WILL BE
AIDED BY LARGE-SCALE ASCENT BENEATH STRONGLY DIFLUENT AND DIVERGENT
UPPER FLOW. GIVEN THE FAVORABLE SHEAR BENEATH STRONG CYCLONIC
MID/UPPER FLOW...IT DOES NOT APPEAR COMPLETELY OUT OF THE QUESTION
THAT INSTABILITY ON A VERY LOCALIZED BASIS COULD BECOME ENOUGH FOR A
SUPERCELL OR TWO WITH THE RISK FOR SEVERE HAIL OR WIND.
000
ACUS11 KWNS 221954
SWOMCD
SPC MCD 221953
PAZ000-MDZ000-VAZ000-WVZ000-222100-
MESOSCALE DISCUSSION 0771
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN/NRN VA...ERN WV PANHANDLE...CNTRL PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221953Z - 222100Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...CONVECTION MAY GRADUALLY INCREASE IN INTENSITY AS IT
PROPAGATES SLOWLY EWD OFF THE HIGHER TERRAIN FROM WRN VA INTO CNTRL
PA.
DISCUSSION...BOUNDARY LAYER HAS WARMED MARKEDLY ACROSS WRN VA/MD
INTO PA WHERE SFC-3KM LAPSE RATES ARE NOW ON THE ORDER OF 8.5 C/KM.
OVER THE LAST OR SO A GRADUAL UPWARD TREND IN CONVECTION HAS BEEN
NOTED ACROSS THE CNTRL APPALACHIANS. IF EXPANDING PRECIP SHIELD
MANAGES TO FORCE AN ORGANIZED OUTFLOW BOUNDARY INTO WRN PLUME OF
HIGHER INSTABILITY...IT MAY SERVE AS THE FOCUS FOR STRONG CONVECTION
FROM PORTIONS OF WRN VA...NWD INTO CNTRL PA. GRADUALLY INCREASING
DEEP LAYER SHEAR MAY ULTIMATELY ALLOW CONVECTION ALONG THE EAST
SLOPES TO LOOSELY ORGANIZE AS THEY PROPAGATE NEWD. DAMAGING WINDS
AND PERHAPS SOME LARGE HAIL ARE THE MAIN CONCERNS. UNTIL
OUTFLOW/CONVECTION BECOME BETTER ORGANIZED SEVERE THREAT SHOULD
REMAIN SOMEWHAT ISOLATED.
..DARROW/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37478032 41257771 40647596 37437900 37478032
000
ACUS11 KWNS 221954
SWOMCD
SPC MCD 221953
PAZ000-MDZ000-VAZ000-WVZ000-222100-
MESOSCALE DISCUSSION 0771
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN/NRN VA...ERN WV PANHANDLE...CNTRL PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221953Z - 222100Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...CONVECTION MAY GRADUALLY INCREASE IN INTENSITY AS IT
PROPAGATES SLOWLY EWD OFF THE HIGHER TERRAIN FROM WRN VA INTO CNTRL
PA.
DISCUSSION...BOUNDARY LAYER HAS WARMED MARKEDLY ACROSS WRN VA/MD
INTO PA WHERE SFC-3KM LAPSE RATES ARE NOW ON THE ORDER OF 8.5 C/KM.
OVER THE LAST OR SO A GRADUAL UPWARD TREND IN CONVECTION HAS BEEN
NOTED ACROSS THE CNTRL APPALACHIANS. IF EXPANDING PRECIP SHIELD
MANAGES TO FORCE AN ORGANIZED OUTFLOW BOUNDARY INTO WRN PLUME OF
HIGHER INSTABILITY...IT MAY SERVE AS THE FOCUS FOR STRONG CONVECTION
FROM PORTIONS OF WRN VA...NWD INTO CNTRL PA. GRADUALLY INCREASING
DEEP LAYER SHEAR MAY ULTIMATELY ALLOW CONVECTION ALONG THE EAST
SLOPES TO LOOSELY ORGANIZE AS THEY PROPAGATE NEWD. DAMAGING WINDS
AND PERHAPS SOME LARGE HAIL ARE THE MAIN CONCERNS. UNTIL
OUTFLOW/CONVECTION BECOME BETTER ORGANIZED SEVERE THREAT SHOULD
REMAIN SOMEWHAT ISOLATED.
..DARROW/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37478032 41257771 40647596 37437900 37478032
000
ACUS11 KWNS 221954
SWOMCD
SPC MCD 221953
PAZ000-MDZ000-VAZ000-WVZ000-222100-
MESOSCALE DISCUSSION 0771
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN/NRN VA...ERN WV PANHANDLE...CNTRL PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221953Z - 222100Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...CONVECTION MAY GRADUALLY INCREASE IN INTENSITY AS IT
PROPAGATES SLOWLY EWD OFF THE HIGHER TERRAIN FROM WRN VA INTO CNTRL
PA.
DISCUSSION...BOUNDARY LAYER HAS WARMED MARKEDLY ACROSS WRN VA/MD
INTO PA WHERE SFC-3KM LAPSE RATES ARE NOW ON THE ORDER OF 8.5 C/KM.
OVER THE LAST OR SO A GRADUAL UPWARD TREND IN CONVECTION HAS BEEN
NOTED ACROSS THE CNTRL APPALACHIANS. IF EXPANDING PRECIP SHIELD
MANAGES TO FORCE AN ORGANIZED OUTFLOW BOUNDARY INTO WRN PLUME OF
HIGHER INSTABILITY...IT MAY SERVE AS THE FOCUS FOR STRONG CONVECTION
FROM PORTIONS OF WRN VA...NWD INTO CNTRL PA. GRADUALLY INCREASING
DEEP LAYER SHEAR MAY ULTIMATELY ALLOW CONVECTION ALONG THE EAST
SLOPES TO LOOSELY ORGANIZE AS THEY PROPAGATE NEWD. DAMAGING WINDS
AND PERHAPS SOME LARGE HAIL ARE THE MAIN CONCERNS. UNTIL
OUTFLOW/CONVECTION BECOME BETTER ORGANIZED SEVERE THREAT SHOULD
REMAIN SOMEWHAT ISOLATED.
..DARROW/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PHI...CTP...LWX...RNK...PBZ...RLX...
LAT...LON 37478032 41257771 40647596 37437900 37478032
000
ACUS11 KWNS 221846
SWOMCD
SPC MCD 221846
NYZ000-PAZ000-222045-
MESOSCALE DISCUSSION 0770
NWS STORM PREDICTION CENTER NORMAN OK
0146 PM CDT WED MAY 22 2013
AREAS AFFECTED...MUCH OF WRN NY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221846Z - 222045Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...ISOLATED STORMS WILL BE POSSIBLE THIS AFTERNOON...WITH
MORE SCATTERED ACTIVITY DEVELOPING AROUND 00Z. HAIL AND/OR WIND WILL
BE THE PRIMARY THREATS EARLY...WITH A TORNADO THREAT MATERIALIZING
LATE.
DISCUSSION...ISOLATED CELLS HAVE DEVELOPED ALONG THE LAKE BREEZE.
ALTHOUGH THERE IS LITTLE ELSE TO FORCE STORMS...CONTINUED HEATING
WILL RESULT IN STEEP LOW LEVEL LAPSE RATES WITH ADDITIONAL FORMATION
POSSIBLE.
WIND SHEAR PROFILES ARE GOING TO INCREASE LATER THIS AFTERNOON INTO
THE EVENING AS THE UPPER TROUGH NEARS. PROFILES WILL BECOME QUITE
FAVORABLE FOR ROTATING STORMS...WITH TORNADOES POSSIBLE.
THE MAIN SEVERE THREAT IS EXPECTED TO COINCIDE WITH THE ARRIVAL OF
BETTER LARGE SCALE ASCENT...CURRENTLY MOVING EWD ACROSS WRN LAKE
ERIE. THE LAKE BREEZE MAY PLAY A ROLE IN FOCUSING DEVELOPMENT...AS
WELL AS ENHANCING LOW LEVEL VORTICITY.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...BGM...BUF...CTP...CLE...
LAT...LON 41997616 41967934 42027963 42227980 42487972 43397913
44407628 44887574 44797526 44397517 42997556 41997616
000
ACUS11 KWNS 221846
SWOMCD
SPC MCD 221846
NYZ000-PAZ000-222045-
MESOSCALE DISCUSSION 0770
NWS STORM PREDICTION CENTER NORMAN OK
0146 PM CDT WED MAY 22 2013
AREAS AFFECTED...MUCH OF WRN NY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221846Z - 222045Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...ISOLATED STORMS WILL BE POSSIBLE THIS AFTERNOON...WITH
MORE SCATTERED ACTIVITY DEVELOPING AROUND 00Z. HAIL AND/OR WIND WILL
BE THE PRIMARY THREATS EARLY...WITH A TORNADO THREAT MATERIALIZING
LATE.
DISCUSSION...ISOLATED CELLS HAVE DEVELOPED ALONG THE LAKE BREEZE.
ALTHOUGH THERE IS LITTLE ELSE TO FORCE STORMS...CONTINUED HEATING
WILL RESULT IN STEEP LOW LEVEL LAPSE RATES WITH ADDITIONAL FORMATION
POSSIBLE.
WIND SHEAR PROFILES ARE GOING TO INCREASE LATER THIS AFTERNOON INTO
THE EVENING AS THE UPPER TROUGH NEARS. PROFILES WILL BECOME QUITE
FAVORABLE FOR ROTATING STORMS...WITH TORNADOES POSSIBLE.
THE MAIN SEVERE THREAT IS EXPECTED TO COINCIDE WITH THE ARRIVAL OF
BETTER LARGE SCALE ASCENT...CURRENTLY MOVING EWD ACROSS WRN LAKE
ERIE. THE LAKE BREEZE MAY PLAY A ROLE IN FOCUSING DEVELOPMENT...AS
WELL AS ENHANCING LOW LEVEL VORTICITY.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BTV...BGM...BUF...CTP...CLE...
LAT...LON 41997616 41967934 42027963 42227980 42487972 43397913
44407628 44887574 44797526 44397517 42997556 41997616
000
ACUS11 KWNS 221808
SWOMCD
SPC MCD 221808
PAZ000-NYZ000-WVZ000-OHZ000-VAZ000-KYZ000-222015-
MESOSCALE DISCUSSION 0769
NWS STORM PREDICTION CENTER NORMAN OK
0108 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN WV...NERN KY...ERN OH...WRN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221808Z - 222015Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...SCATTERED STORMS ARE EXPECTED TO FORM THIS AFTERNOON...AND
SOME MAY EVENTUALLY PRODUCE LOCALIZED SEVERE WIND GUSTS AND/OR
MARGINAL HAIL.
DISCUSSION...SURFACE ANALYSIS SHOWS A ZONE OF HEATING ACROSS THE
AREA WITH TEMPERATURES APPROACHING THE MID 80S F...RESULTING IN A
RELATIVELY UNSTABLE ENVIRONMENT. MEAN DEEP LAYER FLOW IS ALSO A BIT
STRONGER THAN FARTHER E OF THE APPALACHIANS...SUGGESTING FASTER
STORM MOTIONS AND POSSIBLE FORWARD PROPAGATION OF OUTFLOWS. IN
ADDITION...THE STEEP LAPSE RATE ENVIRONMENT SHOULD SUPPORT AT LEAST
MARGINALLY SEVERE HAIL DESPITE WEAK DEEP LAYER SHEAR AND SHORT
HODOGRAPHS.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BUF...CTP...PBZ...RLX...CLE...JKL...ILN...
LAT...LON 42408134 42438055 42257977 42017937 40317934 39757965
38158105 37488200 37358264 37538303 38148324 39798260
40608249 41368249 41728237 42208192 42408134
000
ACUS11 KWNS 221808
SWOMCD
SPC MCD 221808
PAZ000-NYZ000-WVZ000-OHZ000-VAZ000-KYZ000-222015-
MESOSCALE DISCUSSION 0769
NWS STORM PREDICTION CENTER NORMAN OK
0108 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN WV...NERN KY...ERN OH...WRN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221808Z - 222015Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...SCATTERED STORMS ARE EXPECTED TO FORM THIS AFTERNOON...AND
SOME MAY EVENTUALLY PRODUCE LOCALIZED SEVERE WIND GUSTS AND/OR
MARGINAL HAIL.
DISCUSSION...SURFACE ANALYSIS SHOWS A ZONE OF HEATING ACROSS THE
AREA WITH TEMPERATURES APPROACHING THE MID 80S F...RESULTING IN A
RELATIVELY UNSTABLE ENVIRONMENT. MEAN DEEP LAYER FLOW IS ALSO A BIT
STRONGER THAN FARTHER E OF THE APPALACHIANS...SUGGESTING FASTER
STORM MOTIONS AND POSSIBLE FORWARD PROPAGATION OF OUTFLOWS. IN
ADDITION...THE STEEP LAPSE RATE ENVIRONMENT SHOULD SUPPORT AT LEAST
MARGINALLY SEVERE HAIL DESPITE WEAK DEEP LAYER SHEAR AND SHORT
HODOGRAPHS.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BUF...CTP...PBZ...RLX...CLE...JKL...ILN...
LAT...LON 42408134 42438055 42257977 42017937 40317934 39757965
38158105 37488200 37358264 37538303 38148324 39798260
40608249 41368249 41728237 42208192 42408134
000
ACUS11 KWNS 221808
SWOMCD
SPC MCD 221808
PAZ000-NYZ000-WVZ000-OHZ000-VAZ000-KYZ000-222015-
MESOSCALE DISCUSSION 0769
NWS STORM PREDICTION CENTER NORMAN OK
0108 PM CDT WED MAY 22 2013
AREAS AFFECTED...WRN WV...NERN KY...ERN OH...WRN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221808Z - 222015Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...SCATTERED STORMS ARE EXPECTED TO FORM THIS AFTERNOON...AND
SOME MAY EVENTUALLY PRODUCE LOCALIZED SEVERE WIND GUSTS AND/OR
MARGINAL HAIL.
DISCUSSION...SURFACE ANALYSIS SHOWS A ZONE OF HEATING ACROSS THE
AREA WITH TEMPERATURES APPROACHING THE MID 80S F...RESULTING IN A
RELATIVELY UNSTABLE ENVIRONMENT. MEAN DEEP LAYER FLOW IS ALSO A BIT
STRONGER THAN FARTHER E OF THE APPALACHIANS...SUGGESTING FASTER
STORM MOTIONS AND POSSIBLE FORWARD PROPAGATION OF OUTFLOWS. IN
ADDITION...THE STEEP LAPSE RATE ENVIRONMENT SHOULD SUPPORT AT LEAST
MARGINALLY SEVERE HAIL DESPITE WEAK DEEP LAYER SHEAR AND SHORT
HODOGRAPHS.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BUF...CTP...PBZ...RLX...CLE...JKL...ILN...
LAT...LON 42408134 42438055 42257977 42017937 40317934 39757965
38158105 37488200 37358264 37538303 38148324 39798260
40608249 41368249 41728237 42208192 42408134
000
ACUS02 KWNS 221729
SWODY2
SPC AC 221728
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1228 PM CDT WED MAY 22 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER NWRN TX AND WRN OK...
...SYNOPSIS...
UPPER LOW OVER THE UPPER MS VALLEY IS FORECAST TO MOVE EWD AND
WEAKEN TOMORROW AS IT SHEARS NEWD IMMEDIATELY IN ADVANCE OF A SHORT
WAVE TROUGH DIGGING SEWD ACROSS THE GREAT LAKES AND OHIO VALLEY. IN
THE WEST...AN UPPER LOW OVER THE PACIFIC NW IS EXPECTED TO REMAIN
ACROSS THE REGION WHILE AN UPPER RIDGE AMPLIFIES OVER THE PLAINS
STATES. AT THE SURFACE...A LOW IN THE ST. LAWRENCE VALLEY IS
EXPECTED TO LIFT SLOWLY NEWD...AS A TRAILING COLD FRONT MOVES SEWD
FROM THE LOWER GREAT LAKES/OH VALLEY/MID-SOUTH EARLY IN THE PERIOD
REACHING THE ATLANTIC COAST AND NRN GULF COAST BY 24/12Z. THE WRN
PORTION OF THE FRONT WILL EXTEND NWWD INTO NWRN TX AND THE ROCKIES.
...NWRN TX/WRN OK...
A FEW ELEVATED THUNDERSTORMS MAY BE ONGOING EARLY IN THE PERIOD OVER
PARTS OF OK TO THE NORTH OF THE AFOREMENTIONED FRONTAL BOUNDARY
EXTENDING ACROSS NWRN TX. ASSOCIATED CLOUDS/PRECIPITATION MAY DELAY
STRONGER DIABATIC HEATING TO THE NORTH OF THE FRONT RESULTING IN AN
ENHANCEMENT OF THE THERMAL GRADIENT ATTENDING THE FRONT DURING THE
AFTERNOON. WITH SURFACE DEW POINTS IN THE 60S ALONG AND NORTH OF
THE FRONT OVERLAID BY STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH AN
ELEVATED MIXED LAYER...THE ENVIRONMENT IS LIKELY TO BECOME VERY
UNSTABLE WITH MLCAPE REACHING 3000-3500 J/KG. ALTHOUGH DYNAMIC
FORCING FOR LARGE SCALE ASCENT WILL BE MINIMAL WITHIN THE UPPER
RIDGE...LOW LEVEL CONVERGENCE/WARM ADVECTION ALONG AND NORTH OF THE
FRONT COUPLED WITH STRONG HEATING SHOULD WEAKEN THE CAP SUFFICIENTLY
FOR WIDELY SCATTERED STORMS TO DEVELOP DURING THE MID/LATE
AFTERNOON. DESPITE MODEST WINDS ALOFT /25 KT AT 500 MB/...STRONG
DIRECTIONAL SHEAR WITH HEIGHT WILL ENHANCE STORM ORGANIZATION WITH
POTENTIAL FOR A FEW SUPERCELLS TO DEVELOP. STRONGER CELLS WILL BE
CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS...WITH
THE LATTER THREAT INCREASING IF STORMS CAN GROW UPSCALE INTO A SMALL
MCS AND MOVE EWD/SEWD DURING THE EVENING. THERE WILL ALSO BE
POTENTIAL FOR A TORNADO OR TWO TO DEVELOP ESPECIALLY DURING THE
INITIAL PHASE OF SUPERCELL DEVELOPMENT. ACTIVITY IS EXPECTED TO
DIMINISH IN INTENSITY AFTER 03-06Z.
...NEW ENGLAND SWD INTO ERN NC...
MODEL GUIDANCE SUGGESTS THAT CLOUDS AND AREAS OF PRECIPITATION WILL
BE WIDESPREAD AHEAD OF THE COLD FRONT TOMORROW WHICH WILL LIMIT THE
MAGNITUDE OF DIABATIC HEATING AND DESTABILIZATION ACROSS MUCH OF THE
AREA...WITH MLCAPE GENERALLY AOB 1000 J/KG. THERE IS ANTICIPATION
THAT SOME BREAKS IN THE CLOUD COVER WILL PERMIT LOCALIZED REGIONS TO
UNDERGO GREATER DESTABILIZATION...BUT THESE AREAS ARE DIFFICULT TO
IDENTIFY ATTM. AS STRONGER SWLY WINDS ALOFT OVERSPREAD THE
PRE-FRONTAL ENVIRONMENT DURING THE DAY...THERE WILL BE POTENTIAL FOR
A FEW STRONGER STORMS TO DEVELOP. HOWEVER...OWING TO CONCERNS ABOUT
THE EFFECTS OF CLOUDS AND ONGOING CONVECTION ON AIR MASS
STABILITY...WILL MAINTAIN THE CURRENT 5% SEVERE PROBABILITY CORRIDOR
FROM ERN NC INTO NEW ENGLAND. IF IT BECOMES EVIDENT TOMORROW THAT
ZONES OF MORE PRONOUNCED DESTABILIZATION WILL OCCUR...PORTIONS OF
THE AREA MAY REQUIRE AN UPGRADE TO SLIGHT RISK.
..WEISS.. 05/22/2013
000
ACUS02 KWNS 221729
SWODY2
SPC AC 221728
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1228 PM CDT WED MAY 22 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER NWRN TX AND WRN OK...
...SYNOPSIS...
UPPER LOW OVER THE UPPER MS VALLEY IS FORECAST TO MOVE EWD AND
WEAKEN TOMORROW AS IT SHEARS NEWD IMMEDIATELY IN ADVANCE OF A SHORT
WAVE TROUGH DIGGING SEWD ACROSS THE GREAT LAKES AND OHIO VALLEY. IN
THE WEST...AN UPPER LOW OVER THE PACIFIC NW IS EXPECTED TO REMAIN
ACROSS THE REGION WHILE AN UPPER RIDGE AMPLIFIES OVER THE PLAINS
STATES. AT THE SURFACE...A LOW IN THE ST. LAWRENCE VALLEY IS
EXPECTED TO LIFT SLOWLY NEWD...AS A TRAILING COLD FRONT MOVES SEWD
FROM THE LOWER GREAT LAKES/OH VALLEY/MID-SOUTH EARLY IN THE PERIOD
REACHING THE ATLANTIC COAST AND NRN GULF COAST BY 24/12Z. THE WRN
PORTION OF THE FRONT WILL EXTEND NWWD INTO NWRN TX AND THE ROCKIES.
...NWRN TX/WRN OK...
A FEW ELEVATED THUNDERSTORMS MAY BE ONGOING EARLY IN THE PERIOD OVER
PARTS OF OK TO THE NORTH OF THE AFOREMENTIONED FRONTAL BOUNDARY
EXTENDING ACROSS NWRN TX. ASSOCIATED CLOUDS/PRECIPITATION MAY DELAY
STRONGER DIABATIC HEATING TO THE NORTH OF THE FRONT RESULTING IN AN
ENHANCEMENT OF THE THERMAL GRADIENT ATTENDING THE FRONT DURING THE
AFTERNOON. WITH SURFACE DEW POINTS IN THE 60S ALONG AND NORTH OF
THE FRONT OVERLAID BY STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH AN
ELEVATED MIXED LAYER...THE ENVIRONMENT IS LIKELY TO BECOME VERY
UNSTABLE WITH MLCAPE REACHING 3000-3500 J/KG. ALTHOUGH DYNAMIC
FORCING FOR LARGE SCALE ASCENT WILL BE MINIMAL WITHIN THE UPPER
RIDGE...LOW LEVEL CONVERGENCE/WARM ADVECTION ALONG AND NORTH OF THE
FRONT COUPLED WITH STRONG HEATING SHOULD WEAKEN THE CAP SUFFICIENTLY
FOR WIDELY SCATTERED STORMS TO DEVELOP DURING THE MID/LATE
AFTERNOON. DESPITE MODEST WINDS ALOFT /25 KT AT 500 MB/...STRONG
DIRECTIONAL SHEAR WITH HEIGHT WILL ENHANCE STORM ORGANIZATION WITH
POTENTIAL FOR A FEW SUPERCELLS TO DEVELOP. STRONGER CELLS WILL BE
CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS...WITH
THE LATTER THREAT INCREASING IF STORMS CAN GROW UPSCALE INTO A SMALL
MCS AND MOVE EWD/SEWD DURING THE EVENING. THERE WILL ALSO BE
POTENTIAL FOR A TORNADO OR TWO TO DEVELOP ESPECIALLY DURING THE
INITIAL PHASE OF SUPERCELL DEVELOPMENT. ACTIVITY IS EXPECTED TO
DIMINISH IN INTENSITY AFTER 03-06Z.
...NEW ENGLAND SWD INTO ERN NC...
MODEL GUIDANCE SUGGESTS THAT CLOUDS AND AREAS OF PRECIPITATION WILL
BE WIDESPREAD AHEAD OF THE COLD FRONT TOMORROW WHICH WILL LIMIT THE
MAGNITUDE OF DIABATIC HEATING AND DESTABILIZATION ACROSS MUCH OF THE
AREA...WITH MLCAPE GENERALLY AOB 1000 J/KG. THERE IS ANTICIPATION
THAT SOME BREAKS IN THE CLOUD COVER WILL PERMIT LOCALIZED REGIONS TO
UNDERGO GREATER DESTABILIZATION...BUT THESE AREAS ARE DIFFICULT TO
IDENTIFY ATTM. AS STRONGER SWLY WINDS ALOFT OVERSPREAD THE
PRE-FRONTAL ENVIRONMENT DURING THE DAY...THERE WILL BE POTENTIAL FOR
A FEW STRONGER STORMS TO DEVELOP. HOWEVER...OWING TO CONCERNS ABOUT
THE EFFECTS OF CLOUDS AND ONGOING CONVECTION ON AIR MASS
STABILITY...WILL MAINTAIN THE CURRENT 5% SEVERE PROBABILITY CORRIDOR
FROM ERN NC INTO NEW ENGLAND. IF IT BECOMES EVIDENT TOMORROW THAT
ZONES OF MORE PRONOUNCED DESTABILIZATION WILL OCCUR...PORTIONS OF
THE AREA MAY REQUIRE AN UPGRADE TO SLIGHT RISK.
..WEISS.. 05/22/2013
000
ACUS01 KWNS 221612
SWODY1
SPC AC 221610
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1110 AM CDT WED MAY 22 2013
VALID 221630Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN AND EVE ACROSS PARTS
OF THE OH/TN VALLEYS INTO THE LOWER GREAT LAKES REGION AND NEW
ENGLAND....
...SYNOPSIS...
THE PROMINENT BLOCKING PATTERN NOW PRESENT ACROSS MUCH OF WESTERN
AND CENTRAL NORTH AMERICA MAY BEGIN TO WEAKEN DURING THIS FORECAST
PERIOD. AS A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG
SOUTHEAST OF THE HUDSON BAY REGION...THE CLOSED LOW OVER THE UPPER
MISSISSIPPI VALLEY APPEARS LIKELY TO TRANSITION TO AN OPEN WAVE AND
SHIFT EASTWARD INTO THE OHIO VALLEY. A SMALLER SCALE IMPULSE
CURRENTLY PIVOTING AROUND THE SOUTHERN/EASTERN PERIPHERY OF THIS
REMNANT CYCLONIC CIRCULATION IS EXPECTED TO SHIFT NORTHEASTWARD
TOWARD THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION THROUGH
LATE AFTERNOON...BEFORE WEAKENING AND BECOMING INCREASINGLY SHEARED
WITHIN A CONFLUENT REGIME INTO THE CANADIAN MARITIMES.
AT THE SAME TIME...HOWEVER...LITTLE MOVEMENT IS EXPECTED WITH A
LARGE AND COLD MID/UPPER LOW NOW CENTERED OVER THE NORTHERN PACIFIC
COAST STATES. WHILE SOME DEVIATION OF THE CIRCULATION CENTER IS
LIKELY...THIS WILL MOSTLY BE IN RESPONSE TO SHORT WAVE IMPULSES
ROTATING AROUND ITS PERIPHERY.
...OH/TN VALLEYS INTO THE LOWER GREAT LAKES AND NEW ENGLAND...
EXTENSIVE CONVECTION AND ASSOCIATED OUTFLOW FROM YESTERDAY HAS
IMPACTED A SIGNIFICANT PORTION OF THE WARM SECTOR OF THE SURFACE LOW
NOW CENTERED OVER THE UPPER MIDWEST...FROM THE MISSISSIPPI VALLEY
EASTWARD TO THE APPALACHIANS. AND THE FOCUS FOR STORM DEVELOPMENT
LATER THIS AFTERNOON AND EVENING REMAINS A BIT UNCLEAR.
HOWEVER...MODELS CONTINUE TO SUGGEST STRENGTHENING OF LOWER/MID
TROPOSPHERIC FLOW FIELDS /TO AROUND 40 KTS OR SO/ IN A SOUTHERLY
BELT ACROSS PARTS OF THE UPPER OHIO VALLEY INTO THE LEE OF THE LOWER
GREAT LAKES BY LATE THIS AFTERNOON...WHICH SHOULD ENHANCE ANY STORM
DEVELOPMENT OCCURRING IN THE PEAK HEATING.
SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORM DEVELOPMENT...WHICH MAY
EVENTUALLY CONSOLIDATE INTO CLUSTERS OR LINES WITH AN ENHANCED RISK
FOR DAMAGING WIND GUSTS. BUT DISCRETE STORM DEVELOPMENT ALSO WILL
BE POSSIBLE...PARTICULARLY NEAR THE CREST OF BROADER SCALE UPPER
RIDGING ACROSS UPSTATE NEW YORK...WHERE MID/UPPER FLOW WILL BE
SLOWER TO BACK TO A SOUTHERLY DIRECTION. MID-LEVEL LAPSE RATES
APPEAR TO HAVE STABILIZED SOME OVER THE PAST DAY OR SO...BUT SEVERE
HAIL STILL SEEMS POSSIBLE...ALONG WITH A RISK FOR ONE OR TWO
TORNADOES...BEFORE STORMS WEAKEN BY LATE EVENING.
...NORTHERN ROCKIES...
MOISTURE APPEARS MARGINAL FOR VIGOROUS STORM DEVELOPMENT...BUT
STRONGER HEATING ALONG AN AXIS FROM NORTHEAST WYOMING THROUGH
WESTERN MONTANA MAY CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR
SCATTERED STORM DEVELOPMENT THIS AFTERNOON. OROGRAPHIC LIFT WILL BE
AIDED BY LARGE-SCALE ASCENT BENEATH STRONGLY DIFLUENT AND DIVERGENT
UPPER FLOW. GIVEN THE FAVORABLE SHEAR BENEATH STRONG CYCLONIC
MID/UPPER FLOW...IT DOES NOT APPEAR COMPLETELY OUT OF THE QUESTION
THAT INSTABILITY ON A VERY LOCALIZED BASIS COULD BECOME ENOUGH FOR A
SUPERCELL OR TWO WITH THE RISK FOR SEVERE HAIL OR WIND.
..KERR/DARROW.. 05/22/2013
000
ACUS01 KWNS 221612
SWODY1
SPC AC 221610
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1110 AM CDT WED MAY 22 2013
VALID 221630Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN AND EVE ACROSS PARTS
OF THE OH/TN VALLEYS INTO THE LOWER GREAT LAKES REGION AND NEW
ENGLAND....
...SYNOPSIS...
THE PROMINENT BLOCKING PATTERN NOW PRESENT ACROSS MUCH OF WESTERN
AND CENTRAL NORTH AMERICA MAY BEGIN TO WEAKEN DURING THIS FORECAST
PERIOD. AS A SIGNIFICANT SHORT WAVE TROUGH CONTINUES TO DIG
SOUTHEAST OF THE HUDSON BAY REGION...THE CLOSED LOW OVER THE UPPER
MISSISSIPPI VALLEY APPEARS LIKELY TO TRANSITION TO AN OPEN WAVE AND
SHIFT EASTWARD INTO THE OHIO VALLEY. A SMALLER SCALE IMPULSE
CURRENTLY PIVOTING AROUND THE SOUTHERN/EASTERN PERIPHERY OF THIS
REMNANT CYCLONIC CIRCULATION IS EXPECTED TO SHIFT NORTHEASTWARD
TOWARD THE UPPER OHIO VALLEY AND LOWER GREAT LAKES REGION THROUGH
LATE AFTERNOON...BEFORE WEAKENING AND BECOMING INCREASINGLY SHEARED
WITHIN A CONFLUENT REGIME INTO THE CANADIAN MARITIMES.
AT THE SAME TIME...HOWEVER...LITTLE MOVEMENT IS EXPECTED WITH A
LARGE AND COLD MID/UPPER LOW NOW CENTERED OVER THE NORTHERN PACIFIC
COAST STATES. WHILE SOME DEVIATION OF THE CIRCULATION CENTER IS
LIKELY...THIS WILL MOSTLY BE IN RESPONSE TO SHORT WAVE IMPULSES
ROTATING AROUND ITS PERIPHERY.
...OH/TN VALLEYS INTO THE LOWER GREAT LAKES AND NEW ENGLAND...
EXTENSIVE CONVECTION AND ASSOCIATED OUTFLOW FROM YESTERDAY HAS
IMPACTED A SIGNIFICANT PORTION OF THE WARM SECTOR OF THE SURFACE LOW
NOW CENTERED OVER THE UPPER MIDWEST...FROM THE MISSISSIPPI VALLEY
EASTWARD TO THE APPALACHIANS. AND THE FOCUS FOR STORM DEVELOPMENT
LATER THIS AFTERNOON AND EVENING REMAINS A BIT UNCLEAR.
HOWEVER...MODELS CONTINUE TO SUGGEST STRENGTHENING OF LOWER/MID
TROPOSPHERIC FLOW FIELDS /TO AROUND 40 KTS OR SO/ IN A SOUTHERLY
BELT ACROSS PARTS OF THE UPPER OHIO VALLEY INTO THE LEE OF THE LOWER
GREAT LAKES BY LATE THIS AFTERNOON...WHICH SHOULD ENHANCE ANY STORM
DEVELOPMENT OCCURRING IN THE PEAK HEATING.
SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORM DEVELOPMENT...WHICH MAY
EVENTUALLY CONSOLIDATE INTO CLUSTERS OR LINES WITH AN ENHANCED RISK
FOR DAMAGING WIND GUSTS. BUT DISCRETE STORM DEVELOPMENT ALSO WILL
BE POSSIBLE...PARTICULARLY NEAR THE CREST OF BROADER SCALE UPPER
RIDGING ACROSS UPSTATE NEW YORK...WHERE MID/UPPER FLOW WILL BE
SLOWER TO BACK TO A SOUTHERLY DIRECTION. MID-LEVEL LAPSE RATES
APPEAR TO HAVE STABILIZED SOME OVER THE PAST DAY OR SO...BUT SEVERE
HAIL STILL SEEMS POSSIBLE...ALONG WITH A RISK FOR ONE OR TWO
TORNADOES...BEFORE STORMS WEAKEN BY LATE EVENING.
...NORTHERN ROCKIES...
MOISTURE APPEARS MARGINAL FOR VIGOROUS STORM DEVELOPMENT...BUT
STRONGER HEATING ALONG AN AXIS FROM NORTHEAST WYOMING THROUGH
WESTERN MONTANA MAY CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR
SCATTERED STORM DEVELOPMENT THIS AFTERNOON. OROGRAPHIC LIFT WILL BE
AIDED BY LARGE-SCALE ASCENT BENEATH STRONGLY DIFLUENT AND DIVERGENT
UPPER FLOW. GIVEN THE FAVORABLE SHEAR BENEATH STRONG CYCLONIC
MID/UPPER FLOW...IT DOES NOT APPEAR COMPLETELY OUT OF THE QUESTION
THAT INSTABILITY ON A VERY LOCALIZED BASIS COULD BECOME ENOUGH FOR A
SUPERCELL OR TWO WITH THE RISK FOR SEVERE HAIL OR WIND.
..KERR/DARROW.. 05/22/2013
000
ACUS11 KWNS 221532
SWOMCD
SPC MCD 221531
MAZ000-VTZ000-CTZ000-NYZ000-NJZ000-PAZ000-221730-
MESOSCALE DISCUSSION 0768
NWS STORM PREDICTION CENTER NORMAN OK
1031 AM CDT WED MAY 22 2013
AREAS AFFECTED...CNTRL/ERN NY INTO SRN NEW ENGLAND....NERN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221531Z - 221730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...STORMS SHOULD INCREASE IN COVERAGE WITH MAINLY A HAIL
THREAT EARLY THIS AFTERNOON.
DISCUSSION...A WARM AIR MASS WILL CONTINUE TO SPREAD NEWD INTO SRN
NEW ENGLAND WITH CONTINUED HEATING...CREATING SUFFICIENT INSTABILITY
FOR A FEW SEVERE THUNDERSTORMS. 12Z ALB SOUNDING SHOWS MODERATELY
STRONG FLOW AND A SUFFICIENTLY LONG HODOGRAPH FOR A FEW LONG LIVED
STORMS CAPABLE MAINLY OF HAIL. GUSTY WINDS WILL ALSO BE LIKELY.
WHILE DEVELOPMENT MAY BE DISORGANIZED...COVERAGE MAY WARRANT A
WATCH.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 41007524 41347621 41977635 42467639 43107612 43657555
44037471 44027358 43767292 43287264 42577262 42097301
41677339 41187421 41007524
000
ACUS11 KWNS 221532
SWOMCD
SPC MCD 221531
MAZ000-VTZ000-CTZ000-NYZ000-NJZ000-PAZ000-221730-
MESOSCALE DISCUSSION 0768
NWS STORM PREDICTION CENTER NORMAN OK
1031 AM CDT WED MAY 22 2013
AREAS AFFECTED...CNTRL/ERN NY INTO SRN NEW ENGLAND....NERN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221531Z - 221730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...STORMS SHOULD INCREASE IN COVERAGE WITH MAINLY A HAIL
THREAT EARLY THIS AFTERNOON.
DISCUSSION...A WARM AIR MASS WILL CONTINUE TO SPREAD NEWD INTO SRN
NEW ENGLAND WITH CONTINUED HEATING...CREATING SUFFICIENT INSTABILITY
FOR A FEW SEVERE THUNDERSTORMS. 12Z ALB SOUNDING SHOWS MODERATELY
STRONG FLOW AND A SUFFICIENTLY LONG HODOGRAPH FOR A FEW LONG LIVED
STORMS CAPABLE MAINLY OF HAIL. GUSTY WINDS WILL ALSO BE LIKELY.
WHILE DEVELOPMENT MAY BE DISORGANIZED...COVERAGE MAY WARRANT A
WATCH.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 41007524 41347621 41977635 42467639 43107612 43657555
44037471 44027358 43767292 43287264 42577262 42097301
41677339 41187421 41007524
000
ACUS11 KWNS 221532
SWOMCD
SPC MCD 221531
MAZ000-VTZ000-CTZ000-NYZ000-NJZ000-PAZ000-221730-
MESOSCALE DISCUSSION 0768
NWS STORM PREDICTION CENTER NORMAN OK
1031 AM CDT WED MAY 22 2013
AREAS AFFECTED...CNTRL/ERN NY INTO SRN NEW ENGLAND....NERN PA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 221531Z - 221730Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...STORMS SHOULD INCREASE IN COVERAGE WITH MAINLY A HAIL
THREAT EARLY THIS AFTERNOON.
DISCUSSION...A WARM AIR MASS WILL CONTINUE TO SPREAD NEWD INTO SRN
NEW ENGLAND WITH CONTINUED HEATING...CREATING SUFFICIENT INSTABILITY
FOR A FEW SEVERE THUNDERSTORMS. 12Z ALB SOUNDING SHOWS MODERATELY
STRONG FLOW AND A SUFFICIENTLY LONG HODOGRAPH FOR A FEW LONG LIVED
STORMS CAPABLE MAINLY OF HAIL. GUSTY WINDS WILL ALSO BE LIKELY.
WHILE DEVELOPMENT MAY BE DISORGANIZED...COVERAGE MAY WARRANT A
WATCH.
..JEWELL/KERR.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...PHI...BGM...BUF...CTP...
LAT...LON 41007524 41347621 41977635 42467639 43107612 43657555
44037471 44027358 43767292 43287264 42577262 42097301
41677339 41187421 41007524
000
ACUS01 KWNS 221247
SWODY1
SPC AC 221244
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 AM CDT WED MAY 22 2013
VALID 221300Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE TN VALLEY
NORTHEASTWARD INTO NEW ENGLAND...
MORNING WATER VAPOR LOOPS SHOW AN UPPER LOW OVER IA/MN...WITH
SEVERAL WELL-DEFINED VORTICITY MAXIMA ROTATING AROUND THE LOW INTO
THE OH VALLEY. AHEAD OF THESE FEATURES...AMPLE LOW LEVEL MOISTURE
IS IN PLACE AND EARLY SATELLITE IMAGES SHOW MOSTLY CLEAR SKIES
ACROSS PARTS OF OH/WV/PA/NY. SCATTERED STRONG TO SEVERE
THUNDERSTORMS ARE FORECAST TODAY OVER MUCH OF THE TN/OH VALLEY
REGION.
...OH INTO NEW ENGLAND...
MULTIPLE MODEL SOLUTIONS SUGGEST SUBSTANTIAL DESTABILIZATION WILL
OCCUR OVER THIS REGION TODAY. MODELS ALSO SHOW PRONOUNCED
CONVECTIVE COVERAGE THROUGH THE AFTERNOON. GIVEN RATHER STRONG
WESTERLY FLOW ALOFT AND MODERATE CAPE VALUES...THE POTENTIAL WILL
EXIST FOR A CLUSTERING OF SEVERE WEATHER REPORTS ACROSS THIS AREA.
THUS HAVE UPGRADED THE REGION TO 30 PERCENT HAIL AND WIND THREATS.
...TN/OH VALLEYS...
NUMEROUS THUNDERSTORMS HAVE AFFECTED PARTS OF MS/AL OVERNIGHT.
THESE STORMS HAVE REDUCED THE SOUTHERLY LOW LEVEL INFLOW INTO THE TN
VALLEY. ISOLATED SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP IN
THIS REGION LATER THIS AFTERNOON...BUT IT APPEARS THE COVERAGE OF
STORMS FROM TN NORTHWARD INTO WESTERN OH/WV WILL BE RATHER SPARSE..
THEREFORE WILL MAINTAIN THE SLIGHT RISK DESIGNATION FOR THIS REGION
BUT NOT INCLUDE IT IN THE 30 PERCENT UPGRADE.
..HART/LEITMAN.. 05/22/2013
000
ACUS01 KWNS 221247
SWODY1
SPC AC 221244
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 AM CDT WED MAY 22 2013
VALID 221300Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE TN VALLEY
NORTHEASTWARD INTO NEW ENGLAND...
MORNING WATER VAPOR LOOPS SHOW AN UPPER LOW OVER IA/MN...WITH
SEVERAL WELL-DEFINED VORTICITY MAXIMA ROTATING AROUND THE LOW INTO
THE OH VALLEY. AHEAD OF THESE FEATURES...AMPLE LOW LEVEL MOISTURE
IS IN PLACE AND EARLY SATELLITE IMAGES SHOW MOSTLY CLEAR SKIES
ACROSS PARTS OF OH/WV/PA/NY. SCATTERED STRONG TO SEVERE
THUNDERSTORMS ARE FORECAST TODAY OVER MUCH OF THE TN/OH VALLEY
REGION.
...OH INTO NEW ENGLAND...
MULTIPLE MODEL SOLUTIONS SUGGEST SUBSTANTIAL DESTABILIZATION WILL
OCCUR OVER THIS REGION TODAY. MODELS ALSO SHOW PRONOUNCED
CONVECTIVE COVERAGE THROUGH THE AFTERNOON. GIVEN RATHER STRONG
WESTERLY FLOW ALOFT AND MODERATE CAPE VALUES...THE POTENTIAL WILL
EXIST FOR A CLUSTERING OF SEVERE WEATHER REPORTS ACROSS THIS AREA.
THUS HAVE UPGRADED THE REGION TO 30 PERCENT HAIL AND WIND THREATS.
...TN/OH VALLEYS...
NUMEROUS THUNDERSTORMS HAVE AFFECTED PARTS OF MS/AL OVERNIGHT.
THESE STORMS HAVE REDUCED THE SOUTHERLY LOW LEVEL INFLOW INTO THE TN
VALLEY. ISOLATED SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP IN
THIS REGION LATER THIS AFTERNOON...BUT IT APPEARS THE COVERAGE OF
STORMS FROM TN NORTHWARD INTO WESTERN OH/WV WILL BE RATHER SPARSE..
THEREFORE WILL MAINTAIN THE SLIGHT RISK DESIGNATION FOR THIS REGION
BUT NOT INCLUDE IT IN THE 30 PERCENT UPGRADE.
..HART/LEITMAN.. 05/22/2013
000
ACUS03 KWNS 220731
SWODY3
SPC AC 220730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT WED MAY 22 2013
VALID 241200Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
SOME EWD PROGRESSION OF THE ERN U.S. TROUGH IS FORECAST THIS
PERIOD...WHICH WILL ALLOW THE CENTRAL U.S. RIDGE TO BROADEN EWD
SOMEWHAT -- THOUGH PROGGED TO REMAIN FIXED OVER THE CENTRAL U.S.
THROUGH THE PERIOD. MEANWHILE...THE WRN U.S. TROUGH IS EXPECTED TO
REMAIN IN PLACE...THOUGH THE EMBEDDED UPPER LOW OVER THE PAC NW MAY
LIFT SLOWLY NWD/NEWD WITH TIME.
AT THE SURFACE...EXPECT THE ERN U.S. COLD FRONT TO MOVE OFFSHORE
EARLY...TRAILING WWD ACROSS N FL...THE GULF COAST...AND INTO TX
DURING THE AFTERNOON. MEANWHILE...A COLD FRONT WILL LINGER ACROSS
THE INTERMOUNTAIN WEST...WHILE A LEE TROUGH RESIDES ACROSS THE
LENGTH OF THE HIGH PLAINS THROUGH THE PERIOD.
...HIGH PLAINS FROM SERN MT/SWRN ND SWD TO ERN NM/FAR W TX...
AS ISOLATED TO SCATTERED CONVECTION LIKELY ONGOING EARLY IN THE
PERIOD SHIFTS EWD ACROSS THE PLAINS...A DESTABILIZING BUT GENERALLY
CAPPED BOUNDARY LAYER IS EXPECTED TO EXIST W OF THE ONGOING
PRECIPITATION -- ALONG AND AHEAD OF THE LEE TROUGH FORECAST TO
RESIDE OVER THE HIGH PLAINS. SCATTERED STORM REDEVELOPMENT IS
FORECAST INVOF THE LEE TROUGH BY MID TO LATE AFTERNOON -- AS WEAK
MID-LEVEL VORTICITY MAXIMA TRANSLATE EWD INTO THE MEAN RIDGE
POSITION. WITH GENERALLY MODEST /AOB 30 KT/ MID-LEVEL WLYS FORECAST
ATOP LOW-LEVEL SELYS...SHEAR MARGINALLY SUPPORTIVE OF
ORGANIZED-ROTATING UPDRAFTS WILL EXIST -- PARTICULARLY WHERE
LOW-LEVEL FLOW MAY BE LOCALLY STRONGER/MORE VEERED. THIS
COMBINATION OF AMPLE SHEAR/INSTABILITY BUT MEAN LARGE-SCALE RIDGING
SUGGESTS THAT SEVERE THREAT WILL REMAIN ISOLATED IN GENERAL -- AND
THUS WILL INTRODUCE ONLY A BROAD 5% THREAT AREA OVER THE HIGH PLAINS
ATTM. POCKETS OF GREATER THREAT MAY BE ABLE TO BE DISCERNED IN
LATER FORECASTS WHICH COULD WARRANT EVENTUAL INSERTION OF SMALL
SLIGHT RISK AREAS.
..GOSS.. 05/22/2013
000
ACUS03 KWNS 220731
SWODY3
SPC AC 220730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT WED MAY 22 2013
VALID 241200Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
SOME EWD PROGRESSION OF THE ERN U.S. TROUGH IS FORECAST THIS
PERIOD...WHICH WILL ALLOW THE CENTRAL U.S. RIDGE TO BROADEN EWD
SOMEWHAT -- THOUGH PROGGED TO REMAIN FIXED OVER THE CENTRAL U.S.
THROUGH THE PERIOD. MEANWHILE...THE WRN U.S. TROUGH IS EXPECTED TO
REMAIN IN PLACE...THOUGH THE EMBEDDED UPPER LOW OVER THE PAC NW MAY
LIFT SLOWLY NWD/NEWD WITH TIME.
AT THE SURFACE...EXPECT THE ERN U.S. COLD FRONT TO MOVE OFFSHORE
EARLY...TRAILING WWD ACROSS N FL...THE GULF COAST...AND INTO TX
DURING THE AFTERNOON. MEANWHILE...A COLD FRONT WILL LINGER ACROSS
THE INTERMOUNTAIN WEST...WHILE A LEE TROUGH RESIDES ACROSS THE
LENGTH OF THE HIGH PLAINS THROUGH THE PERIOD.
...HIGH PLAINS FROM SERN MT/SWRN ND SWD TO ERN NM/FAR W TX...
AS ISOLATED TO SCATTERED CONVECTION LIKELY ONGOING EARLY IN THE
PERIOD SHIFTS EWD ACROSS THE PLAINS...A DESTABILIZING BUT GENERALLY
CAPPED BOUNDARY LAYER IS EXPECTED TO EXIST W OF THE ONGOING
PRECIPITATION -- ALONG AND AHEAD OF THE LEE TROUGH FORECAST TO
RESIDE OVER THE HIGH PLAINS. SCATTERED STORM REDEVELOPMENT IS
FORECAST INVOF THE LEE TROUGH BY MID TO LATE AFTERNOON -- AS WEAK
MID-LEVEL VORTICITY MAXIMA TRANSLATE EWD INTO THE MEAN RIDGE
POSITION. WITH GENERALLY MODEST /AOB 30 KT/ MID-LEVEL WLYS FORECAST
ATOP LOW-LEVEL SELYS...SHEAR MARGINALLY SUPPORTIVE OF
ORGANIZED-ROTATING UPDRAFTS WILL EXIST -- PARTICULARLY WHERE
LOW-LEVEL FLOW MAY BE LOCALLY STRONGER/MORE VEERED. THIS
COMBINATION OF AMPLE SHEAR/INSTABILITY BUT MEAN LARGE-SCALE RIDGING
SUGGESTS THAT SEVERE THREAT WILL REMAIN ISOLATED IN GENERAL -- AND
THUS WILL INTRODUCE ONLY A BROAD 5% THREAT AREA OVER THE HIGH PLAINS
ATTM. POCKETS OF GREATER THREAT MAY BE ABLE TO BE DISCERNED IN
LATER FORECASTS WHICH COULD WARRANT EVENTUAL INSERTION OF SMALL
SLIGHT RISK AREAS.
..GOSS.. 05/22/2013
000
ACUS02 KWNS 220600
SWODY2
SPC AC 220559
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1259 AM CDT WED MAY 22 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE TX PANHANDLE
VICINITY...
...SYNOPSIS...
CONTINUED EWD PROGRESSION OF THE LARGE-SCALE ERN U.S. TROUGH IS
EXPECTED THIS PERIOD...THOUGH OCCURRING IN STAGES AS SEVERAL
SMALLER-SCALE FEATURES DIG/ROTATE AROUND THE LARGER-SCALE TROUGH.
MEANWHILE...A LARGE UPPER LOW/TROUGH WILL REMAIN QUASI-STATIONARY
OVER THE WRN U.S. -- BLOCKED BY A STOUT RIDGE OVER THE CENTRAL U.S.
AND CANADIAN PRAIRIE PROVINCES.
AT THE SURFACE...A COLD FRONT EXTENDING FROM MT SWWD INTO THE GREAT
BASIN REGION WILL MAKE ONLY SLOW EWD PROGRESS...WHILE A COLD FRONT
MOVING ACROSS THE ERN U.S. SHOULD CROSS THE APPALACHIANS DURING THE
AFTERNOON AND EVENING AND APPROACH THE COAST LATE.
...TX PANHANDLE VICINITY...
SELY FLOW ON THE COOL SIDE OF THE LOW/WARM FRONT -- PROGGED TO LIE
NW-SE ACROSS CENTRAL TX DURING THE AFTERNOON -- BENEATH 20 TO 30 KT
MID-LEVEL WLYS WILL RESULT BOTH IN SHEAR SUPPORTIVE OF
SUPERCELLS...AND UPSLOPE-INDUCED ASCENT. STILL...WITH RIDGING ALOFT
RESULTING IN LARGE-SCALE SUBSIDENCE...CAPPING IS EXPECTED TO HINDER
STORM DEVELOPMENT THROUGH MUCH OF THE AFTERNOON.
MODELS CONTINUE TO HINT THAT ISOLATED CONVECTIVE DEVELOPMENT WILL
EVENTUALLY OCCUR...AND WITH AFOREMENTIONED SHEAR AVAILABLE ALONG
WITH 1000 TO 1500 J/KG CAPE BECOMING REALIZED IF THE CAP CAN INDEED
MIX OUT LOCALLY...LARGE HAIL AND LOCALLY DAMAGING WINDS WOULD BE
POSSIBLE WITH SUPERCELL STORMS...ALONG WITH POSSIBLY AN ISOLATED
TORNADO OR TWO. WHILE THIS REMAINS A CONDITIONAL THREAT...WILL
MAINTAIN 15%/SLIGHT RISK GIVEN DEGREE OF POTENTIAL PRESUMING STORM
INITIATION.
...WRN NEW ENGLAND SWD ACROSS THE MID-ATLANTIC REGION TO ERN NC...
GENERALLY WEAK INSTABILITY IS PROGGED AHEAD OF THE COLD FRONT AS IT
ADVANCES ACROSS THE LOWER GREAT LAKES REGION THROUGH THE DAY -- AND
THEN E OF THE APPALACHIANS THROUGH THE EVENING. THUS -- EXPECT
CONVECTIVE INTENSIFICATION TO BE HINDERED IN MOST AREAS. HAVING
SAID THAT...MODERATE FLOW ALOFT SPREADING ACROSS THIS AREA COULD
ALLOW A FEW STRONGER STORMS TO ORGANIZE WHERE POCKETS OF GREATER
DESTABILIZATION MAY OCCUR. THEREFORE -- WITH LOCAL HAIL/WIND
POTENTIAL STILL EVIDENT...WILL MAINTAIN LOW SEVERE PROBABILITY/SEE
TEXT ACROSS THIS REGION.
..GOSS.. 05/22/2013
000
ACUS02 KWNS 220600
SWODY2
SPC AC 220559
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1259 AM CDT WED MAY 22 2013
VALID 231200Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE TX PANHANDLE
VICINITY...
...SYNOPSIS...
CONTINUED EWD PROGRESSION OF THE LARGE-SCALE ERN U.S. TROUGH IS
EXPECTED THIS PERIOD...THOUGH OCCURRING IN STAGES AS SEVERAL
SMALLER-SCALE FEATURES DIG/ROTATE AROUND THE LARGER-SCALE TROUGH.
MEANWHILE...A LARGE UPPER LOW/TROUGH WILL REMAIN QUASI-STATIONARY
OVER THE WRN U.S. -- BLOCKED BY A STOUT RIDGE OVER THE CENTRAL U.S.
AND CANADIAN PRAIRIE PROVINCES.
AT THE SURFACE...A COLD FRONT EXTENDING FROM MT SWWD INTO THE GREAT
BASIN REGION WILL MAKE ONLY SLOW EWD PROGRESS...WHILE A COLD FRONT
MOVING ACROSS THE ERN U.S. SHOULD CROSS THE APPALACHIANS DURING THE
AFTERNOON AND EVENING AND APPROACH THE COAST LATE.
...TX PANHANDLE VICINITY...
SELY FLOW ON THE COOL SIDE OF THE LOW/WARM FRONT -- PROGGED TO LIE
NW-SE ACROSS CENTRAL TX DURING THE AFTERNOON -- BENEATH 20 TO 30 KT
MID-LEVEL WLYS WILL RESULT BOTH IN SHEAR SUPPORTIVE OF
SUPERCELLS...AND UPSLOPE-INDUCED ASCENT. STILL...WITH RIDGING ALOFT
RESULTING IN LARGE-SCALE SUBSIDENCE...CAPPING IS EXPECTED TO HINDER
STORM DEVELOPMENT THROUGH MUCH OF THE AFTERNOON.
MODELS CONTINUE TO HINT THAT ISOLATED CONVECTIVE DEVELOPMENT WILL
EVENTUALLY OCCUR...AND WITH AFOREMENTIONED SHEAR AVAILABLE ALONG
WITH 1000 TO 1500 J/KG CAPE BECOMING REALIZED IF THE CAP CAN INDEED
MIX OUT LOCALLY...LARGE HAIL AND LOCALLY DAMAGING WINDS WOULD BE
POSSIBLE WITH SUPERCELL STORMS...ALONG WITH POSSIBLY AN ISOLATED
TORNADO OR TWO. WHILE THIS REMAINS A CONDITIONAL THREAT...WILL
MAINTAIN 15%/SLIGHT RISK GIVEN DEGREE OF POTENTIAL PRESUMING STORM
INITIATION.
...WRN NEW ENGLAND SWD ACROSS THE MID-ATLANTIC REGION TO ERN NC...
GENERALLY WEAK INSTABILITY IS PROGGED AHEAD OF THE COLD FRONT AS IT
ADVANCES ACROSS THE LOWER GREAT LAKES REGION THROUGH THE DAY -- AND
THEN E OF THE APPALACHIANS THROUGH THE EVENING. THUS -- EXPECT
CONVECTIVE INTENSIFICATION TO BE HINDERED IN MOST AREAS. HAVING
SAID THAT...MODERATE FLOW ALOFT SPREADING ACROSS THIS AREA COULD
ALLOW A FEW STRONGER STORMS TO ORGANIZE WHERE POCKETS OF GREATER
DESTABILIZATION MAY OCCUR. THEREFORE -- WITH LOCAL HAIL/WIND
POTENTIAL STILL EVIDENT...WILL MAINTAIN LOW SEVERE PROBABILITY/SEE
TEXT ACROSS THIS REGION.
..GOSS.. 05/22/2013
000
ACUS01 KWNS 220550
SWODY1
SPC AC 220548
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1248 AM CDT WED MAY 22 2013
VALID 221200Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER GREAT
LAKES...OH VALLEY AND TN VALLEY...
...LOWER GREAT LAKES/OH VALLEY/TN VALLEY...
A POSITIVELY-TILTED UPPER-LEVEL TROUGH WILL MOVE EWD ACROSS THE MID
TO UPPER MS VALLEY TODAY WITH SOUTHWEST FLOW LOCATED AHEAD OF THE
SYSTEM FROM THE TN VALLEY NWD INTO THE LOWER GREAT LAKES. AT THE
SFC...A LOW IS FORECAST TO MOVE ENEWD ACROSS LOWER MI WITH A
CORRIDOR OF MOISTURE WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F
EXTENDING NWD FROM THE TN VALLEY INTO THE UPPER OH VALLEY AND LOWER
GREAT LAKES REGION. MODEL FORECASTS SUGGEST SEVERAL THUNDERSTORM
CLUSTERS WILL BE ONGOING THIS MORNING WITH CONVECTIVE COVERAGE
RAPIDLY INCREASING ACROSS THE WRN EDGE OF MODERATE INSTABILITY THIS
AFTERNOON. MCS DEVELOPMENT WILL BE POSSIBLE ACROSS PARTS OF THE
SLIGHT RISK AREA LATE THIS AFTERNOON WITH SEVERAL CONVECTIVE
CLUSTERS PERSISTING INTO THE EVENING AHEAD OF THE APPROACHING
UPPER-LEVEL TROUGH.
FORECAST SOUNDINGS AT 21Z AT ROCHESTER NY...COLUMBUS OH AND
LEXINGTON KY SHOW SBCAPE VALUES FROM 750 TO 1250 J/KG WITH STEEP
LOW-LEVEL LAPSE RATES AND 35 TO 40 KT OF 0-6 KM SHEAR. THIS
ENVIRONMENT SHOULD BE FAVORABLE FOR DAMAGING WIND GUSTS AS CELLS
INCREASE IN COVERAGE AND INTENSITY LATE THIS AFTERNOON. THE GREATEST
POTENTIAL FOR WIND DAMAGE SHOULD EXIST FROM LAKE ERIE SWD ACROSS
MUCH OF OH ALONG THE AXIS OF A 30 TO 40 KT LOW-LEVEL JET. THE WIND
DAMAGE THREAT COULD BECOME ENHANCED IF A LINEAR MCS CAN ORGANIZE
ACROSS THE UPPER OH VALLEY. A FEW TORNADOES MAY OCCUR WITH ROTATING
CELL ELEMENTS EMBEDDED IN THE MCS. LARGE HAIL COULD ALSO ACCOMPANY
THE MORE INTENSE CELLS BUT THE HAIL THREAT SHOULD REMAIN ISOLATED
MAINLY DUE TO THE RELATIVELY WEAK INSTABILITY.
...CNTRL GULF COAST/LOWER MS VALLEY...
THE SRN EXTENSION OF AN UPPER-LEVEL TROUGH WILL MOVE ACROSS THE
LOWER MS VALLEY TODAY WITH A SFC TROUGH LOCATED ACROSS ERN AR AND
LA. TO THE EAST OF THE SFC TROUGH...DEWPOINTS SHOULD BE IN THE MID
TO UPPER 60S F WITH MODERATE INSTABILITY DEVELOPING BY AFTERNOON.
THE MODELS INITIATE SCATTERED THUNDERSTORMS AHEAD OF THE SFC TROUGH
WHERE FORECAST SOUNDINGS SHOW STEEP LOW-LEVEL LAPSE RATES. THIS
ALONG WITH THE ABUNDANT LOW-LEVEL MOISTURE COULD BE ENOUGH FOR
MARGINALLY SEVERE WET DOWNBURSTS ASSOCIATED WITH THE BETTER
ORGANIZED MULTICELLS.
..BROYLES/MEAD.. 05/22/2013
000
ACUS01 KWNS 220550
SWODY1
SPC AC 220548
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1248 AM CDT WED MAY 22 2013
VALID 221200Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER GREAT
LAKES...OH VALLEY AND TN VALLEY...
...LOWER GREAT LAKES/OH VALLEY/TN VALLEY...
A POSITIVELY-TILTED UPPER-LEVEL TROUGH WILL MOVE EWD ACROSS THE MID
TO UPPER MS VALLEY TODAY WITH SOUTHWEST FLOW LOCATED AHEAD OF THE
SYSTEM FROM THE TN VALLEY NWD INTO THE LOWER GREAT LAKES. AT THE
SFC...A LOW IS FORECAST TO MOVE ENEWD ACROSS LOWER MI WITH A
CORRIDOR OF MOISTURE WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F
EXTENDING NWD FROM THE TN VALLEY INTO THE UPPER OH VALLEY AND LOWER
GREAT LAKES REGION. MODEL FORECASTS SUGGEST SEVERAL THUNDERSTORM
CLUSTERS WILL BE ONGOING THIS MORNING WITH CONVECTIVE COVERAGE
RAPIDLY INCREASING ACROSS THE WRN EDGE OF MODERATE INSTABILITY THIS
AFTERNOON. MCS DEVELOPMENT WILL BE POSSIBLE ACROSS PARTS OF THE
SLIGHT RISK AREA LATE THIS AFTERNOON WITH SEVERAL CONVECTIVE
CLUSTERS PERSISTING INTO THE EVENING AHEAD OF THE APPROACHING
UPPER-LEVEL TROUGH.
FORECAST SOUNDINGS AT 21Z AT ROCHESTER NY...COLUMBUS OH AND
LEXINGTON KY SHOW SBCAPE VALUES FROM 750 TO 1250 J/KG WITH STEEP
LOW-LEVEL LAPSE RATES AND 35 TO 40 KT OF 0-6 KM SHEAR. THIS
ENVIRONMENT SHOULD BE FAVORABLE FOR DAMAGING WIND GUSTS AS CELLS
INCREASE IN COVERAGE AND INTENSITY LATE THIS AFTERNOON. THE GREATEST
POTENTIAL FOR WIND DAMAGE SHOULD EXIST FROM LAKE ERIE SWD ACROSS
MUCH OF OH ALONG THE AXIS OF A 30 TO 40 KT LOW-LEVEL JET. THE WIND
DAMAGE THREAT COULD BECOME ENHANCED IF A LINEAR MCS CAN ORGANIZE
ACROSS THE UPPER OH VALLEY. A FEW TORNADOES MAY OCCUR WITH ROTATING
CELL ELEMENTS EMBEDDED IN THE MCS. LARGE HAIL COULD ALSO ACCOMPANY
THE MORE INTENSE CELLS BUT THE HAIL THREAT SHOULD REMAIN ISOLATED
MAINLY DUE TO THE RELATIVELY WEAK INSTABILITY.
...CNTRL GULF COAST/LOWER MS VALLEY...
THE SRN EXTENSION OF AN UPPER-LEVEL TROUGH WILL MOVE ACROSS THE
LOWER MS VALLEY TODAY WITH A SFC TROUGH LOCATED ACROSS ERN AR AND
LA. TO THE EAST OF THE SFC TROUGH...DEWPOINTS SHOULD BE IN THE MID
TO UPPER 60S F WITH MODERATE INSTABILITY DEVELOPING BY AFTERNOON.
THE MODELS INITIATE SCATTERED THUNDERSTORMS AHEAD OF THE SFC TROUGH
WHERE FORECAST SOUNDINGS SHOW STEEP LOW-LEVEL LAPSE RATES. THIS
ALONG WITH THE ABUNDANT LOW-LEVEL MOISTURE COULD BE ENOUGH FOR
MARGINALLY SEVERE WET DOWNBURSTS ASSOCIATED WITH THE BETTER
ORGANIZED MULTICELLS.
..BROYLES/MEAD.. 05/22/2013
000
ACUS11 KWNS 220441
SWOMCD
SPC MCD 220441
ALZ000-MSZ000-LAZ000-220545-
MESOSCALE DISCUSSION 0767
NWS STORM PREDICTION CENTER NORMAN OK
1141 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL LA / CNTRL AND N-CNTRL MS
CONCERNING...SEVERE THUNDERSTORM WATCH 209...
VALID 220441Z - 220545Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 209
CONTINUES.
SUMMARY...POCKETS OF STRONG TO MARGINALLY SEVERE WIND GUSTS WILL
LIKELY POSE AN ISOLATED WIND DAMAGE THREAT THE NEXT COUPLE OF HOURS
IN PLACES WHERE THE SQUALL LINE EXHIBITS A MORE EWD COMPONENT TO ITS
MOTION.
DISCUSSION...SUBJECTIVE MESOANALYSIS SHOWS AN ARCING GUST FRONT/COLD
POOL LOCATED OVER NERN MS WHERE TEMPS ARE AROUND 70 WITH LOWER 60S
DEWPOINTS. SOUTH OF THIS BOUNDARY...TEMPS IN THE MID 70S AND
DEWPOINTS RANGING FROM THE MID 60S-70 DEG F CHARACTERIZE A MORE
UNSTABLE AIRMASS --- POTENTIALLY MORE CONDUCIVE FOR WIND GUSTS TO
REACH THE SURFACE. THE QLCS IS ADVANCING TOWARDS THE KDGX RADAR AT
34 KT AND INBOUND VELOCITIES SHOW UPWARDS OF 40-50 KTS AT 1500 AGL.
ADDITIONALLY...KTVR OBSERVED A 40 KT WIND GUST DURING THE PAST HOUR.
IN SUMMARY...THE REGION SOUTH OF THE OUTFLOW BOUNDARY FROM N-CNTRL
MS INTO SWRN MS --WHERE THE GREATEST EWD COMPONENT TO THE QLCS
MOTION IS LOCATED-- WILL REMAIN THE FAVORED AREA FOR POCKETS OF
35-50 KT WIND GUSTS CAPABLE OF ISOLATED WIND DAMAGE.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...MEG...JAN...LIX...
LAT...LON 33708831 33728940 32039099 31579177 31279106 31498969
32558874 33298813 33708831
000
ACUS11 KWNS 220441
SWOMCD
SPC MCD 220441
ALZ000-MSZ000-LAZ000-220545-
MESOSCALE DISCUSSION 0767
NWS STORM PREDICTION CENTER NORMAN OK
1141 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL LA / CNTRL AND N-CNTRL MS
CONCERNING...SEVERE THUNDERSTORM WATCH 209...
VALID 220441Z - 220545Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 209
CONTINUES.
SUMMARY...POCKETS OF STRONG TO MARGINALLY SEVERE WIND GUSTS WILL
LIKELY POSE AN ISOLATED WIND DAMAGE THREAT THE NEXT COUPLE OF HOURS
IN PLACES WHERE THE SQUALL LINE EXHIBITS A MORE EWD COMPONENT TO ITS
MOTION.
DISCUSSION...SUBJECTIVE MESOANALYSIS SHOWS AN ARCING GUST FRONT/COLD
POOL LOCATED OVER NERN MS WHERE TEMPS ARE AROUND 70 WITH LOWER 60S
DEWPOINTS. SOUTH OF THIS BOUNDARY...TEMPS IN THE MID 70S AND
DEWPOINTS RANGING FROM THE MID 60S-70 DEG F CHARACTERIZE A MORE
UNSTABLE AIRMASS --- POTENTIALLY MORE CONDUCIVE FOR WIND GUSTS TO
REACH THE SURFACE. THE QLCS IS ADVANCING TOWARDS THE KDGX RADAR AT
34 KT AND INBOUND VELOCITIES SHOW UPWARDS OF 40-50 KTS AT 1500 AGL.
ADDITIONALLY...KTVR OBSERVED A 40 KT WIND GUST DURING THE PAST HOUR.
IN SUMMARY...THE REGION SOUTH OF THE OUTFLOW BOUNDARY FROM N-CNTRL
MS INTO SWRN MS --WHERE THE GREATEST EWD COMPONENT TO THE QLCS
MOTION IS LOCATED-- WILL REMAIN THE FAVORED AREA FOR POCKETS OF
35-50 KT WIND GUSTS CAPABLE OF ISOLATED WIND DAMAGE.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...MEG...JAN...LIX...
LAT...LON 33708831 33728940 32039099 31579177 31279106 31498969
32558874 33298813 33708831
000
ACUS11 KWNS 220441
SWOMCD
SPC MCD 220441
ALZ000-MSZ000-LAZ000-220545-
MESOSCALE DISCUSSION 0767
NWS STORM PREDICTION CENTER NORMAN OK
1141 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL LA / CNTRL AND N-CNTRL MS
CONCERNING...SEVERE THUNDERSTORM WATCH 209...
VALID 220441Z - 220545Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 209
CONTINUES.
SUMMARY...POCKETS OF STRONG TO MARGINALLY SEVERE WIND GUSTS WILL
LIKELY POSE AN ISOLATED WIND DAMAGE THREAT THE NEXT COUPLE OF HOURS
IN PLACES WHERE THE SQUALL LINE EXHIBITS A MORE EWD COMPONENT TO ITS
MOTION.
DISCUSSION...SUBJECTIVE MESOANALYSIS SHOWS AN ARCING GUST FRONT/COLD
POOL LOCATED OVER NERN MS WHERE TEMPS ARE AROUND 70 WITH LOWER 60S
DEWPOINTS. SOUTH OF THIS BOUNDARY...TEMPS IN THE MID 70S AND
DEWPOINTS RANGING FROM THE MID 60S-70 DEG F CHARACTERIZE A MORE
UNSTABLE AIRMASS --- POTENTIALLY MORE CONDUCIVE FOR WIND GUSTS TO
REACH THE SURFACE. THE QLCS IS ADVANCING TOWARDS THE KDGX RADAR AT
34 KT AND INBOUND VELOCITIES SHOW UPWARDS OF 40-50 KTS AT 1500 AGL.
ADDITIONALLY...KTVR OBSERVED A 40 KT WIND GUST DURING THE PAST HOUR.
IN SUMMARY...THE REGION SOUTH OF THE OUTFLOW BOUNDARY FROM N-CNTRL
MS INTO SWRN MS --WHERE THE GREATEST EWD COMPONENT TO THE QLCS
MOTION IS LOCATED-- WILL REMAIN THE FAVORED AREA FOR POCKETS OF
35-50 KT WIND GUSTS CAPABLE OF ISOLATED WIND DAMAGE.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...MEG...JAN...LIX...
LAT...LON 33708831 33728940 32039099 31579177 31279106 31498969
32558874 33298813 33708831
000
ACUS11 KWNS 220420
SWOMCD
SPC MCD 220420
LAZ000-TXZ000-220515-
MESOSCALE DISCUSSION 0766
NWS STORM PREDICTION CENTER NORMAN OK
1120 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SERN TX
CONCERNING...SEVERE THUNDERSTORM WATCH 208...
VALID 220420Z - 220515Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 208
CONTINUES.
SUMMARY...A SEVERE WIND GUST THREAT CONTINUES WITH THE MORE INTENSE
STORMS.
DISCUSSION...RADAR MOSAIC SHOWS A CLUSTER OF STORMS /INCLUDING THE
MONTGOMERY-WALKER COUNTY SUPERCELL/ OVER SERN TX. ALTHOUGH THE
LEADING EDGE OF THE GUST FRONT IS 5-10 MI DISPLACED SE OF THIS STORM
CLUSTER...MOISTURE RICH SELY LOW LEVEL FLOW --FEATURING LOWER 70S
DEWPOINTS-- EXISTS AHEAD OF THE ESEWD MOVING SUPERCELL. ALTHOUGH A
TORNADO CANNOT BE RULED OUT...ISOLD WIND DAMAGE CONTINUES TO BE THE
PRIMARY THREAT WITH THESE STORMS AS 45 KT 0-6 KM SHEAR WILL SUPPORT
A CONTINUED ORGANIZED SEVERE STORM THREAT FOR THE NEXT FEW HOURS.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...
LAT...LON 30299375 30139613 30459646 31059476 31019390 30679367
30299375
000
ACUS11 KWNS 220420
SWOMCD
SPC MCD 220420
LAZ000-TXZ000-220515-
MESOSCALE DISCUSSION 0766
NWS STORM PREDICTION CENTER NORMAN OK
1120 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SERN TX
CONCERNING...SEVERE THUNDERSTORM WATCH 208...
VALID 220420Z - 220515Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 208
CONTINUES.
SUMMARY...A SEVERE WIND GUST THREAT CONTINUES WITH THE MORE INTENSE
STORMS.
DISCUSSION...RADAR MOSAIC SHOWS A CLUSTER OF STORMS /INCLUDING THE
MONTGOMERY-WALKER COUNTY SUPERCELL/ OVER SERN TX. ALTHOUGH THE
LEADING EDGE OF THE GUST FRONT IS 5-10 MI DISPLACED SE OF THIS STORM
CLUSTER...MOISTURE RICH SELY LOW LEVEL FLOW --FEATURING LOWER 70S
DEWPOINTS-- EXISTS AHEAD OF THE ESEWD MOVING SUPERCELL. ALTHOUGH A
TORNADO CANNOT BE RULED OUT...ISOLD WIND DAMAGE CONTINUES TO BE THE
PRIMARY THREAT WITH THESE STORMS AS 45 KT 0-6 KM SHEAR WILL SUPPORT
A CONTINUED ORGANIZED SEVERE STORM THREAT FOR THE NEXT FEW HOURS.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...
LAT...LON 30299375 30139613 30459646 31059476 31019390 30679367
30299375
000
ACUS11 KWNS 220420
SWOMCD
SPC MCD 220420
LAZ000-TXZ000-220515-
MESOSCALE DISCUSSION 0766
NWS STORM PREDICTION CENTER NORMAN OK
1120 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SERN TX
CONCERNING...SEVERE THUNDERSTORM WATCH 208...
VALID 220420Z - 220515Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 208
CONTINUES.
SUMMARY...A SEVERE WIND GUST THREAT CONTINUES WITH THE MORE INTENSE
STORMS.
DISCUSSION...RADAR MOSAIC SHOWS A CLUSTER OF STORMS /INCLUDING THE
MONTGOMERY-WALKER COUNTY SUPERCELL/ OVER SERN TX. ALTHOUGH THE
LEADING EDGE OF THE GUST FRONT IS 5-10 MI DISPLACED SE OF THIS STORM
CLUSTER...MOISTURE RICH SELY LOW LEVEL FLOW --FEATURING LOWER 70S
DEWPOINTS-- EXISTS AHEAD OF THE ESEWD MOVING SUPERCELL. ALTHOUGH A
TORNADO CANNOT BE RULED OUT...ISOLD WIND DAMAGE CONTINUES TO BE THE
PRIMARY THREAT WITH THESE STORMS AS 45 KT 0-6 KM SHEAR WILL SUPPORT
A CONTINUED ORGANIZED SEVERE STORM THREAT FOR THE NEXT FEW HOURS.
..SMITH.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...
LAT...LON 30299375 30139613 30459646 31059476 31019390 30679367
30299375
000
ACUS11 KWNS 220222
SWOMCD
SPC MCD 220222
ALZ000-MSZ000-220245-
MESOSCALE DISCUSSION 0765
NWS STORM PREDICTION CENTER NORMAN OK
0922 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NERN MS / FAR NWRN AL
CONCERNING...TORNADO WATCH 207...
VALID 220222Z - 220245Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...A MARGINAL WIND DAMAGE THREAT MAY PERSIST BEYOND 03Z. A
NEW SEVERE THUNDERSTORM WATCH ISSUANCE IS UNLIKELY /ONLY 20 PERCENT/
DOWNSTREAM ACROSS NRN AL.
DISCUSSION...RADAR MOSAIC SHOWS A SURGING GUST FRONT BECOMING
INCREASINGLY DISPLACED FROM THE WEAKENING QLCS NEAR THE TN/AL/MS
BORDER WITH THIS BOUNDARY ARCING SWWD TO A MORE VIGOROUS UPDRAFT
LOCATED OVER YALOBUSHA COUNTY MS. THE SRN FLANKING STORMS
EXHIBITING CELLULAR CHARACTERISTICS MAY POSE A LOCALIZED STRONG WIND
GUST THREAT OVER THE NEXT HOUR OR SO...AND A LOCAL WATCH
EXTENSION-IN-TIME IS A POSSIBLE OPTION OVER PARTS OF NERN MS.
FARTHER N...THE ANAFRONTAL CHARACTER OF THE QLCS WILL ACT TO FURTHER
WEAKEN THE CONVECTIVE LINE WITH A GREATLY DIMINISHED WIND GUST
THREAT FARTHER N TOWARDS THE TN BORDER.
..SMITH/CORFIDI.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...HUN...MEG...JAN...
LAT...LON 34908812 34428937 33758999 33718872 34038772 34628758
34908812
000
ACUS11 KWNS 220222
SWOMCD
SPC MCD 220222
ALZ000-MSZ000-220245-
MESOSCALE DISCUSSION 0765
NWS STORM PREDICTION CENTER NORMAN OK
0922 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NERN MS / FAR NWRN AL
CONCERNING...TORNADO WATCH 207...
VALID 220222Z - 220245Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...A MARGINAL WIND DAMAGE THREAT MAY PERSIST BEYOND 03Z. A
NEW SEVERE THUNDERSTORM WATCH ISSUANCE IS UNLIKELY /ONLY 20 PERCENT/
DOWNSTREAM ACROSS NRN AL.
DISCUSSION...RADAR MOSAIC SHOWS A SURGING GUST FRONT BECOMING
INCREASINGLY DISPLACED FROM THE WEAKENING QLCS NEAR THE TN/AL/MS
BORDER WITH THIS BOUNDARY ARCING SWWD TO A MORE VIGOROUS UPDRAFT
LOCATED OVER YALOBUSHA COUNTY MS. THE SRN FLANKING STORMS
EXHIBITING CELLULAR CHARACTERISTICS MAY POSE A LOCALIZED STRONG WIND
GUST THREAT OVER THE NEXT HOUR OR SO...AND A LOCAL WATCH
EXTENSION-IN-TIME IS A POSSIBLE OPTION OVER PARTS OF NERN MS.
FARTHER N...THE ANAFRONTAL CHARACTER OF THE QLCS WILL ACT TO FURTHER
WEAKEN THE CONVECTIVE LINE WITH A GREATLY DIMINISHED WIND GUST
THREAT FARTHER N TOWARDS THE TN BORDER.
..SMITH/CORFIDI.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...HUN...MEG...JAN...
LAT...LON 34908812 34428937 33758999 33718872 34038772 34628758
34908812
000
ACUS11 KWNS 220222
SWOMCD
SPC MCD 220222
ALZ000-MSZ000-220245-
MESOSCALE DISCUSSION 0765
NWS STORM PREDICTION CENTER NORMAN OK
0922 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NERN MS / FAR NWRN AL
CONCERNING...TORNADO WATCH 207...
VALID 220222Z - 220245Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...A MARGINAL WIND DAMAGE THREAT MAY PERSIST BEYOND 03Z. A
NEW SEVERE THUNDERSTORM WATCH ISSUANCE IS UNLIKELY /ONLY 20 PERCENT/
DOWNSTREAM ACROSS NRN AL.
DISCUSSION...RADAR MOSAIC SHOWS A SURGING GUST FRONT BECOMING
INCREASINGLY DISPLACED FROM THE WEAKENING QLCS NEAR THE TN/AL/MS
BORDER WITH THIS BOUNDARY ARCING SWWD TO A MORE VIGOROUS UPDRAFT
LOCATED OVER YALOBUSHA COUNTY MS. THE SRN FLANKING STORMS
EXHIBITING CELLULAR CHARACTERISTICS MAY POSE A LOCALIZED STRONG WIND
GUST THREAT OVER THE NEXT HOUR OR SO...AND A LOCAL WATCH
EXTENSION-IN-TIME IS A POSSIBLE OPTION OVER PARTS OF NERN MS.
FARTHER N...THE ANAFRONTAL CHARACTER OF THE QLCS WILL ACT TO FURTHER
WEAKEN THE CONVECTIVE LINE WITH A GREATLY DIMINISHED WIND GUST
THREAT FARTHER N TOWARDS THE TN BORDER.
..SMITH/CORFIDI.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...HUN...MEG...JAN...
LAT...LON 34908812 34428937 33758999 33718872 34038772 34628758
34908812
000
ACUS01 KWNS 220101
SWODY1
SPC AC 220059
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 PM CDT TUE MAY 21 2013
VALID 220100Z - 221200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE TN
VALLEY...LOWER MS VALLEY AND SRN PLAINS...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF ERN
NY...VT...NH AND MA...
...TN VALLEY/LOWER MS VALLEY/SRN PLAINS...
SEVERAL LINEAR MESOSCALE CONVECTIVE SYSTEMS ARE ONGOING FROM WRN TN
SWWD ACROSS NW MS INTO NW LA AND EAST TX. THE STORMS ARE LOCATED ON
THE NWRN EDGE OF A CORRIDOR OF MODERATE INSTABILITY. MLCAPE VALUES
ACROSS THE WARM SECTOR ARE ESTIMATED IN THE 2000 TO 3000 J/KG RANGE
FROM THE SRN PLAINS ENEWD INTO THE LOWER MS VALLEY. THIS ALONG WITH
LARGE-SCALE ASCENT ASSOCIATED WITH AN UPPER-LEVEL TROUGH IN THE SRN
PLAINS WILL CONTINUE TO SUPPORT MCS DEVELOPMENT THIS EVENING. IN
ADDITION...A 50 TO 65 KT MID-LEVEL JET IS ANALYZED OVER THE ERN
PARTS OF THE SRN PLAINS. THIS FEATURE IS CREATING MODERATE DEEP
LAYER SHEAR PROFILES ACROSS MUCH OF THE WARM SECTOR WHICH WILL HELP
TO MAINTAIN A SEVERE THREAT THROUGH THE MID EVENING. REGIONAL
WSR-88D VWPS ACROSS THE WARM SECTOR SHOW UNIDIRECTIONAL WINDS IN THE
BOUNDARY LAYER WITH ABOUT 20 TO 30 KT OF FLOW. THIS COINCIDING WITH
0-3 KM LAPSE RATES OF 7.0 TO 7.5 C/KM SHOULD BE FAVORABLE FOR
DAMAGING WIND GUSTS WITH THE MORE ORGANIZED BOWING LINE SEGMENTS. AN
ISOLATED THREAT FOR HAIL AND A BRIEF TORNADO WILL BE POSSIBLE WITH
ROTATING CELLS ELEMENTS. HOWEVER...THE LOW-LEVEL WIND PROFILES
APPEAR MOST FAVORABLE FOR DAMAGING WIND GUSTS.
....NRN APPALACHIAN MTNS...
THE LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL RIDGE IN PLACE
ACROSS THE APPALACHIAN MTNS WITH A DISTURBANCE MOVING EWD ACROSS THE
TOP OF THE RIDGE INTO NY AND NEW ENGLAND. THIS FEATURE IS SUPPORTING
AN ARCHING LINE OF THUNDERSTORMS EXTENDING SWWD ACROSS NERN...CNTRL
AND SRN NY. MLCAPE VALUES AHEAD OF THE LINE ARE ESTIMATED TO BE IN
THE 500 TO 1500 J/KG RANGE. THIS COMBINED WITH MODERATE TO STRONG
DEEP LAYER SHEAR PROFILES WILL HELP SUPPORT THE LINE FOR SEVERAL
MORE HOURS THIS EVENING. THE ALBANY NY WSR-88D VWP SHOWS DIRECTIONAL
TURNING BELOW 2 KM AGL WITH 25 TO 30 KT OF FLOW IN THE LOW TO
MID-LEVELS. THE LOW-LEVEL WIND APPEARS FAVORABLE FOR WIND DAMAGE AS
A BOWING LINE SEGMENT MOVES EWD ACROSS ERN NY...VT...NH AND MA OVER
THE NEXT FEW HOURS. HAIL WILL ALSO BE POSSIBLE WITH THE MORE INTENSE
CELLS.
..BROYLES.. 05/22/2013
000
ACUS01 KWNS 220101
SWODY1
SPC AC 220059
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 PM CDT TUE MAY 21 2013
VALID 220100Z - 221200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE TN
VALLEY...LOWER MS VALLEY AND SRN PLAINS...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF ERN
NY...VT...NH AND MA...
...TN VALLEY/LOWER MS VALLEY/SRN PLAINS...
SEVERAL LINEAR MESOSCALE CONVECTIVE SYSTEMS ARE ONGOING FROM WRN TN
SWWD ACROSS NW MS INTO NW LA AND EAST TX. THE STORMS ARE LOCATED ON
THE NWRN EDGE OF A CORRIDOR OF MODERATE INSTABILITY. MLCAPE VALUES
ACROSS THE WARM SECTOR ARE ESTIMATED IN THE 2000 TO 3000 J/KG RANGE
FROM THE SRN PLAINS ENEWD INTO THE LOWER MS VALLEY. THIS ALONG WITH
LARGE-SCALE ASCENT ASSOCIATED WITH AN UPPER-LEVEL TROUGH IN THE SRN
PLAINS WILL CONTINUE TO SUPPORT MCS DEVELOPMENT THIS EVENING. IN
ADDITION...A 50 TO 65 KT MID-LEVEL JET IS ANALYZED OVER THE ERN
PARTS OF THE SRN PLAINS. THIS FEATURE IS CREATING MODERATE DEEP
LAYER SHEAR PROFILES ACROSS MUCH OF THE WARM SECTOR WHICH WILL HELP
TO MAINTAIN A SEVERE THREAT THROUGH THE MID EVENING. REGIONAL
WSR-88D VWPS ACROSS THE WARM SECTOR SHOW UNIDIRECTIONAL WINDS IN THE
BOUNDARY LAYER WITH ABOUT 20 TO 30 KT OF FLOW. THIS COINCIDING WITH
0-3 KM LAPSE RATES OF 7.0 TO 7.5 C/KM SHOULD BE FAVORABLE FOR
DAMAGING WIND GUSTS WITH THE MORE ORGANIZED BOWING LINE SEGMENTS. AN
ISOLATED THREAT FOR HAIL AND A BRIEF TORNADO WILL BE POSSIBLE WITH
ROTATING CELLS ELEMENTS. HOWEVER...THE LOW-LEVEL WIND PROFILES
APPEAR MOST FAVORABLE FOR DAMAGING WIND GUSTS.
....NRN APPALACHIAN MTNS...
THE LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL RIDGE IN PLACE
ACROSS THE APPALACHIAN MTNS WITH A DISTURBANCE MOVING EWD ACROSS THE
TOP OF THE RIDGE INTO NY AND NEW ENGLAND. THIS FEATURE IS SUPPORTING
AN ARCHING LINE OF THUNDERSTORMS EXTENDING SWWD ACROSS NERN...CNTRL
AND SRN NY. MLCAPE VALUES AHEAD OF THE LINE ARE ESTIMATED TO BE IN
THE 500 TO 1500 J/KG RANGE. THIS COMBINED WITH MODERATE TO STRONG
DEEP LAYER SHEAR PROFILES WILL HELP SUPPORT THE LINE FOR SEVERAL
MORE HOURS THIS EVENING. THE ALBANY NY WSR-88D VWP SHOWS DIRECTIONAL
TURNING BELOW 2 KM AGL WITH 25 TO 30 KT OF FLOW IN THE LOW TO
MID-LEVELS. THE LOW-LEVEL WIND APPEARS FAVORABLE FOR WIND DAMAGE AS
A BOWING LINE SEGMENT MOVES EWD ACROSS ERN NY...VT...NH AND MA OVER
THE NEXT FEW HOURS. HAIL WILL ALSO BE POSSIBLE WITH THE MORE INTENSE
CELLS.
..BROYLES.. 05/22/2013
000
ACUS11 KWNS 220040
SWOMCD
SPC MCD 220039
ALZ000-MSZ000-LAZ000-TXZ000-220245-
MESOSCALE DISCUSSION 0764
NWS STORM PREDICTION CENTER NORMAN OK
0739 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL - NERN LA / CNTRL MS
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 220039Z - 220245Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...A LOCALLY DAMAGING WIND THREAT WILL PROBABLY MOVE INTO
NERN LA AND CNTRL MS BY THE MID-LATE EVENING. ADDITIONAL
STRONG-SEVERE POTENTIAL WILL INCREASE FARTHER SW OVER CNTRL LA.
DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SQUALL LINE SEGMENTED
INTO SEVERAL QLCS INTERCONNECTED BY A MODIFYING OUTFLOW BOUNDARY
LOCATED FROM THE SRN EXTENSION OF THE NRN MS QLCS WWD TO THE SRN
AR/NWRN LA QLCS. ALTHOUGH SOME SLIGHT SURFACE COOLING WILL OCCUR
PRIOR TO THE APPROACH OF THE QLCS FROM THE NW...THE 00Z/22 JAN RAOB
EXHIBITED A MOIST AND MODERATELY UNSTABLE BOUNDARY LAYER WITH DEEP
LAYER SHEAR /25-30 KT/ SUPPORTIVE OF A LINEAR MCS. RECENT KSHV VWP
DATA SHOW A 40-45 KT REAR INFLOW JET ASSOCIATED WITH THE QLCS AND A
35 KT GUST WAS OBSERVED AT KSHV. AS A RESULT...A CONTINUATION OF A
35-50 KT WIND GUST THREAT CAPABLE OF POCKETS OF WIND DAMAGE WILL
LIKELY MOVE INTO THE DISCUSSION AREA OVER THE NEXT SEVERAL HOURS.
..SMITH/CORFIDI.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...JAN...LIX...LCH...SHV...
LAT...LON 33548896 33398845 33018819 32558835 30389326 30629355
31029356 31399341 32509186 33548896
000
ACUS11 KWNS 220040
SWOMCD
SPC MCD 220039
ALZ000-MSZ000-LAZ000-TXZ000-220245-
MESOSCALE DISCUSSION 0764
NWS STORM PREDICTION CENTER NORMAN OK
0739 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL - NERN LA / CNTRL MS
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 220039Z - 220245Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...A LOCALLY DAMAGING WIND THREAT WILL PROBABLY MOVE INTO
NERN LA AND CNTRL MS BY THE MID-LATE EVENING. ADDITIONAL
STRONG-SEVERE POTENTIAL WILL INCREASE FARTHER SW OVER CNTRL LA.
DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SQUALL LINE SEGMENTED
INTO SEVERAL QLCS INTERCONNECTED BY A MODIFYING OUTFLOW BOUNDARY
LOCATED FROM THE SRN EXTENSION OF THE NRN MS QLCS WWD TO THE SRN
AR/NWRN LA QLCS. ALTHOUGH SOME SLIGHT SURFACE COOLING WILL OCCUR
PRIOR TO THE APPROACH OF THE QLCS FROM THE NW...THE 00Z/22 JAN RAOB
EXHIBITED A MOIST AND MODERATELY UNSTABLE BOUNDARY LAYER WITH DEEP
LAYER SHEAR /25-30 KT/ SUPPORTIVE OF A LINEAR MCS. RECENT KSHV VWP
DATA SHOW A 40-45 KT REAR INFLOW JET ASSOCIATED WITH THE QLCS AND A
35 KT GUST WAS OBSERVED AT KSHV. AS A RESULT...A CONTINUATION OF A
35-50 KT WIND GUST THREAT CAPABLE OF POCKETS OF WIND DAMAGE WILL
LIKELY MOVE INTO THE DISCUSSION AREA OVER THE NEXT SEVERAL HOURS.
..SMITH/CORFIDI.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BMX...JAN...LIX...LCH...SHV...
LAT...LON 33548896 33398845 33018819 32558835 30389326 30629355
31029356 31399341 32509186 33548896
000
ACUS11 KWNS 220030
SWOMCD
SPC MCD 220029
MAZ000-NHZ000-RIZ000-CTZ000-VTZ000-NYZ000-PAZ000-220130-
MESOSCALE DISCUSSION 0763
NWS STORM PREDICTION CENTER NORMAN OK
0729 PM CDT TUE MAY 21 2013
AREAS AFFECTED...UPSTATE NY / SRN PARTS OF VT AND NH / WRN AND CNTRL
MA / NRN PARTS OF CT AND RI
CONCERNING...SEVERE THUNDERSTORM WATCH 203...204...
VALID 220029Z - 220130Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
203...204...CONTINUES.
SUMMARY...THE THREAT FOR DAMAGING WINDS AND HAIL MAY CONTINUE BEYOND
THE 01Z EXPIRATION OF SEVERE THUNDERSTORM WATCHES 203 AND 204. A
LOCAL EXTENSION OF PORTIONS OF WW 203 AREA MAY BE NECESSARY.
DISCUSSION...AS OF 00Z...REGIONAL RADAR IMAGERY SHOWED A LOOSELY
ORGANIZED MCS FROM CLINTON AND ESSEX COUNTIES TO MADISON AND
CHENANGO COUNTIES IN NY WITH AN EWD SYSTEM MOTION OF 35-40 KT.
WHILE THE NRN EXTENT OF THIS MCS WILL MOVE INTO A PROGRESSIVELY
COOLER AND MORE STABLE AIR MASS IN PLACE OVER NRN VT...THE SRN
PORTION WILL MAINTAIN AN INFLOW OF AT LEAST MODEST INSTABILITY /SEE
00Z ALB SOUNDING/...SUGGESTING A CONTINUED DAMAGING WIND AND HAIL
THREAT AS IT MOVES INTO THE HUDSON VALLEY. OVER WRN AND CNTRL PARTS
OF NY...ISOLATED OCCURRENCES OF MARGINALLY SEVERE HAIL WILL REMAIN
POSSIBLE OVER THE NEXT HOUR OR TWO WITH STORMS DEVELOPING ALONG THE
OUTFLOW BOUNDARY TRAILING THE MCS.
..MEAD.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...BGM...BUF...
LAT...LON 43177877 43307690 43587522 44027437 43787331 43337307
43007213 42407161 41897151 41677217 41577387 41677490
42147568 42077718 42197811 42167886 42447916 42927886
43177877
000
ACUS11 KWNS 220030
SWOMCD
SPC MCD 220029
MAZ000-NHZ000-RIZ000-CTZ000-VTZ000-NYZ000-PAZ000-220130-
MESOSCALE DISCUSSION 0763
NWS STORM PREDICTION CENTER NORMAN OK
0729 PM CDT TUE MAY 21 2013
AREAS AFFECTED...UPSTATE NY / SRN PARTS OF VT AND NH / WRN AND CNTRL
MA / NRN PARTS OF CT AND RI
CONCERNING...SEVERE THUNDERSTORM WATCH 203...204...
VALID 220029Z - 220130Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
203...204...CONTINUES.
SUMMARY...THE THREAT FOR DAMAGING WINDS AND HAIL MAY CONTINUE BEYOND
THE 01Z EXPIRATION OF SEVERE THUNDERSTORM WATCHES 203 AND 204. A
LOCAL EXTENSION OF PORTIONS OF WW 203 AREA MAY BE NECESSARY.
DISCUSSION...AS OF 00Z...REGIONAL RADAR IMAGERY SHOWED A LOOSELY
ORGANIZED MCS FROM CLINTON AND ESSEX COUNTIES TO MADISON AND
CHENANGO COUNTIES IN NY WITH AN EWD SYSTEM MOTION OF 35-40 KT.
WHILE THE NRN EXTENT OF THIS MCS WILL MOVE INTO A PROGRESSIVELY
COOLER AND MORE STABLE AIR MASS IN PLACE OVER NRN VT...THE SRN
PORTION WILL MAINTAIN AN INFLOW OF AT LEAST MODEST INSTABILITY /SEE
00Z ALB SOUNDING/...SUGGESTING A CONTINUED DAMAGING WIND AND HAIL
THREAT AS IT MOVES INTO THE HUDSON VALLEY. OVER WRN AND CNTRL PARTS
OF NY...ISOLATED OCCURRENCES OF MARGINALLY SEVERE HAIL WILL REMAIN
POSSIBLE OVER THE NEXT HOUR OR TWO WITH STORMS DEVELOPING ALONG THE
OUTFLOW BOUNDARY TRAILING THE MCS.
..MEAD.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...BGM...BUF...
LAT...LON 43177877 43307690 43587522 44027437 43787331 43337307
43007213 42407161 41897151 41677217 41577387 41677490
42147568 42077718 42197811 42167886 42447916 42927886
43177877
000
ACUS11 KWNS 220030
SWOMCD
SPC MCD 220029
MAZ000-NHZ000-RIZ000-CTZ000-VTZ000-NYZ000-PAZ000-220130-
MESOSCALE DISCUSSION 0763
NWS STORM PREDICTION CENTER NORMAN OK
0729 PM CDT TUE MAY 21 2013
AREAS AFFECTED...UPSTATE NY / SRN PARTS OF VT AND NH / WRN AND CNTRL
MA / NRN PARTS OF CT AND RI
CONCERNING...SEVERE THUNDERSTORM WATCH 203...204...
VALID 220029Z - 220130Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
203...204...CONTINUES.
SUMMARY...THE THREAT FOR DAMAGING WINDS AND HAIL MAY CONTINUE BEYOND
THE 01Z EXPIRATION OF SEVERE THUNDERSTORM WATCHES 203 AND 204. A
LOCAL EXTENSION OF PORTIONS OF WW 203 AREA MAY BE NECESSARY.
DISCUSSION...AS OF 00Z...REGIONAL RADAR IMAGERY SHOWED A LOOSELY
ORGANIZED MCS FROM CLINTON AND ESSEX COUNTIES TO MADISON AND
CHENANGO COUNTIES IN NY WITH AN EWD SYSTEM MOTION OF 35-40 KT.
WHILE THE NRN EXTENT OF THIS MCS WILL MOVE INTO A PROGRESSIVELY
COOLER AND MORE STABLE AIR MASS IN PLACE OVER NRN VT...THE SRN
PORTION WILL MAINTAIN AN INFLOW OF AT LEAST MODEST INSTABILITY /SEE
00Z ALB SOUNDING/...SUGGESTING A CONTINUED DAMAGING WIND AND HAIL
THREAT AS IT MOVES INTO THE HUDSON VALLEY. OVER WRN AND CNTRL PARTS
OF NY...ISOLATED OCCURRENCES OF MARGINALLY SEVERE HAIL WILL REMAIN
POSSIBLE OVER THE NEXT HOUR OR TWO WITH STORMS DEVELOPING ALONG THE
OUTFLOW BOUNDARY TRAILING THE MCS.
..MEAD.. 05/22/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...BTV...OKX...ALY...BGM...BUF...
LAT...LON 43177877 43307690 43587522 44027437 43787331 43337307
43007213 42407161 41897151 41677217 41577387 41677490
42147568 42077718 42197811 42167886 42447916 42927886
43177877
000
ACUS11 KWNS 212323
SWOMCD
SPC MCD 212323
TNZ000-ALZ000-MSZ000-ARZ000-220030-
MESOSCALE DISCUSSION 0762
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN-MIDDLE TN / FAR NWRN AL / NRN MS / FAR SERN AR
CONCERNING...TORNADO WATCH 207...
VALID 212323Z - 220030Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...ISOLD POCKETS OF WIND DAMAGE APPEAR TO BE THE MAIN THREAT.
TORNADO POTENTIAL WILL LIKELY REMAIN LIMITED BASED ON LINEAR
CONVECTIVE MODE.
DISCUSSION...RADAR MOSAIC SHOWS AN ORGANIZED QLCS FROM FAR SRN IL
SWD TO E OF THE GREATER MEMPHIS METRO SWWD INTO SERN AR. THE NRN
PORTION OF THE QLCS FROM NEAR MEM NWD INTO WRN KY REMAINS LARGELY
SUB-SEVERE AND SURFACE OBS OVER WRN TN SUPPORT THIS NOTION WITH ASOS
GUSTS AT TIME OF QLCS PASSAGE REMAINING BELOW 30 KT. SURFACE
ANALYSIS SHOWS A LARGELY WEST-EAST ORIENTED OUTFLOW BOUNDARY
EXTENDING FROM THE TRAILING PORTION OF THE SRN APPALACHIANS QLCS
WESTWARD AND INTERSECTING THE QLCS 25 MI ESE MEM. EARLIER IN THE
DAY SUBSTANTIAL CONVECTIVE OVERTURNING OCCURRED N OF THIS BOUNDARY
ACROSS WRN AND MIDDLE TN -- LIMITING THE MAGNITUDE OF
DESTABILIZATION OCCURRING IN ITS WAKE. CURRENT THINKING IS THE TN
PORTION OF THE QLCS MAY ONLY POSE A LOW DAMAGING WIND THREAT.
FARTHER S OVER NRN MS...A WARM/UNSTABLE AIRMASS AHEAD OF THIS
CONVECTIVE LINE IS MORE FAVORABLE FOR ISOLD POCKETS OF WIND DAMAGE
GIVEN THE STEEPER LOW LEVEL LAPSE RATES. IT IS UNCERTAIN HOW FAR
EAST THIS QLCS MAY POSE AN ISOLD DAMAGING WIND THREAT...ESPECIALLY
SINCE THE BOUNDARY LAYER WILL BEGIN TO COOL BY THE TIME THE QLCS
APPROACHES THE ERN EDGE OF THE WATCH NEAR THE NERN MS/NWRN AL
BORDER. ALTHOUGH A BRIEF TORNADO IS POSSIBLE NEAR THE OUTFLOW
BOUNDARY-QLCS INTERSECTION...THIS THREAT WILL LIKELY REMAIN LIMITED
BASED ON THE LINEAR CONVECTIVE MODE.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...BMX...HUN...MEG...JAN...LZK...
LAT...LON 36478874 35098975 33489168 33019107 33018934 34268807
35638754 36378760 36478874
000
ACUS11 KWNS 212323
SWOMCD
SPC MCD 212323
TNZ000-ALZ000-MSZ000-ARZ000-220030-
MESOSCALE DISCUSSION 0762
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN-MIDDLE TN / FAR NWRN AL / NRN MS / FAR SERN AR
CONCERNING...TORNADO WATCH 207...
VALID 212323Z - 220030Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...ISOLD POCKETS OF WIND DAMAGE APPEAR TO BE THE MAIN THREAT.
TORNADO POTENTIAL WILL LIKELY REMAIN LIMITED BASED ON LINEAR
CONVECTIVE MODE.
DISCUSSION...RADAR MOSAIC SHOWS AN ORGANIZED QLCS FROM FAR SRN IL
SWD TO E OF THE GREATER MEMPHIS METRO SWWD INTO SERN AR. THE NRN
PORTION OF THE QLCS FROM NEAR MEM NWD INTO WRN KY REMAINS LARGELY
SUB-SEVERE AND SURFACE OBS OVER WRN TN SUPPORT THIS NOTION WITH ASOS
GUSTS AT TIME OF QLCS PASSAGE REMAINING BELOW 30 KT. SURFACE
ANALYSIS SHOWS A LARGELY WEST-EAST ORIENTED OUTFLOW BOUNDARY
EXTENDING FROM THE TRAILING PORTION OF THE SRN APPALACHIANS QLCS
WESTWARD AND INTERSECTING THE QLCS 25 MI ESE MEM. EARLIER IN THE
DAY SUBSTANTIAL CONVECTIVE OVERTURNING OCCURRED N OF THIS BOUNDARY
ACROSS WRN AND MIDDLE TN -- LIMITING THE MAGNITUDE OF
DESTABILIZATION OCCURRING IN ITS WAKE. CURRENT THINKING IS THE TN
PORTION OF THE QLCS MAY ONLY POSE A LOW DAMAGING WIND THREAT.
FARTHER S OVER NRN MS...A WARM/UNSTABLE AIRMASS AHEAD OF THIS
CONVECTIVE LINE IS MORE FAVORABLE FOR ISOLD POCKETS OF WIND DAMAGE
GIVEN THE STEEPER LOW LEVEL LAPSE RATES. IT IS UNCERTAIN HOW FAR
EAST THIS QLCS MAY POSE AN ISOLD DAMAGING WIND THREAT...ESPECIALLY
SINCE THE BOUNDARY LAYER WILL BEGIN TO COOL BY THE TIME THE QLCS
APPROACHES THE ERN EDGE OF THE WATCH NEAR THE NERN MS/NWRN AL
BORDER. ALTHOUGH A BRIEF TORNADO IS POSSIBLE NEAR THE OUTFLOW
BOUNDARY-QLCS INTERSECTION...THIS THREAT WILL LIKELY REMAIN LIMITED
BASED ON THE LINEAR CONVECTIVE MODE.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...BMX...HUN...MEG...JAN...LZK...
LAT...LON 36478874 35098975 33489168 33019107 33018934 34268807
35638754 36378760 36478874
000
ACUS11 KWNS 212323
SWOMCD
SPC MCD 212323
TNZ000-ALZ000-MSZ000-ARZ000-220030-
MESOSCALE DISCUSSION 0762
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN-MIDDLE TN / FAR NWRN AL / NRN MS / FAR SERN AR
CONCERNING...TORNADO WATCH 207...
VALID 212323Z - 220030Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 207 CONTINUES.
SUMMARY...ISOLD POCKETS OF WIND DAMAGE APPEAR TO BE THE MAIN THREAT.
TORNADO POTENTIAL WILL LIKELY REMAIN LIMITED BASED ON LINEAR
CONVECTIVE MODE.
DISCUSSION...RADAR MOSAIC SHOWS AN ORGANIZED QLCS FROM FAR SRN IL
SWD TO E OF THE GREATER MEMPHIS METRO SWWD INTO SERN AR. THE NRN
PORTION OF THE QLCS FROM NEAR MEM NWD INTO WRN KY REMAINS LARGELY
SUB-SEVERE AND SURFACE OBS OVER WRN TN SUPPORT THIS NOTION WITH ASOS
GUSTS AT TIME OF QLCS PASSAGE REMAINING BELOW 30 KT. SURFACE
ANALYSIS SHOWS A LARGELY WEST-EAST ORIENTED OUTFLOW BOUNDARY
EXTENDING FROM THE TRAILING PORTION OF THE SRN APPALACHIANS QLCS
WESTWARD AND INTERSECTING THE QLCS 25 MI ESE MEM. EARLIER IN THE
DAY SUBSTANTIAL CONVECTIVE OVERTURNING OCCURRED N OF THIS BOUNDARY
ACROSS WRN AND MIDDLE TN -- LIMITING THE MAGNITUDE OF
DESTABILIZATION OCCURRING IN ITS WAKE. CURRENT THINKING IS THE TN
PORTION OF THE QLCS MAY ONLY POSE A LOW DAMAGING WIND THREAT.
FARTHER S OVER NRN MS...A WARM/UNSTABLE AIRMASS AHEAD OF THIS
CONVECTIVE LINE IS MORE FAVORABLE FOR ISOLD POCKETS OF WIND DAMAGE
GIVEN THE STEEPER LOW LEVEL LAPSE RATES. IT IS UNCERTAIN HOW FAR
EAST THIS QLCS MAY POSE AN ISOLD DAMAGING WIND THREAT...ESPECIALLY
SINCE THE BOUNDARY LAYER WILL BEGIN TO COOL BY THE TIME THE QLCS
APPROACHES THE ERN EDGE OF THE WATCH NEAR THE NERN MS/NWRN AL
BORDER. ALTHOUGH A BRIEF TORNADO IS POSSIBLE NEAR THE OUTFLOW
BOUNDARY-QLCS INTERSECTION...THIS THREAT WILL LIKELY REMAIN LIMITED
BASED ON THE LINEAR CONVECTIVE MODE.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...BMX...HUN...MEG...JAN...LZK...
LAT...LON 36478874 35098975 33489168 33019107 33018934 34268807
35638754 36378760 36478874
000
ACUS11 KWNS 212300
SWOMCD
SPC MCD 212300
WVZ000-VAZ000-TNZ000-KYZ000-OHZ000-NCZ000-220000-
MESOSCALE DISCUSSION 0761
NWS STORM PREDICTION CENTER NORMAN OK
0600 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN KY / WRN WV / FAR SERN OH / WRN VA / ERN TN
CONCERNING...SEVERE THUNDERSTORM WATCH 206...
VALID 212300Z - 220000Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 206
CONTINUES.
SUMMARY...THE THREAT FOR MAINLY DAMAGING WINDS CONTINUES ACROSS
REMAINING VALID PORTION OF WATCH AREA THIS EVENING.
DISCUSSION...AS OF 2240Z...REGIONAL RADAR IMAGERY INDICATED THE
LEADING EDGE OF AN EWD-MOVING MCS FROM NEAR THE OH RIVER 40 SE
LUK-20 E JKL-30 E OF TYS. THE KY SEGMENT OF THIS CONVECTIVE SYSTEM
HAS REMAINED MOST PROGRESSIVE /AROUND 30 KT/ WHERE AN EXTENSIVE
TRAILING STRATIFORM REGION AND ASSOCIATED 40-45 KT REAR-INFLOW JET
/RIJ --SEE CURRENT JKL VAD/ HAVE DEVELOPED. UPSLOPE FLOW COMBINED
WITH RIJ-ENHANCED CONVERGENCE ALONG THE LEADING EDGE OF THE SYSTEM
COLD POOL SHOULD CONTINUE TO PROMOTE FORWARD PROPAGATION --AND AN
ASSOCIATED DAMAGING WIND THREAT-- INTO WRN WV BY 22/00Z.
FARTHER S INTO ERN TN...THE MCS IS MUCH MORE FRAGMENTED AND NOT AS
PROGRESSIVE. NONETHELESS...ISOLATED OCCURRENCES OF LOCALLY DAMAGING
WINDS WILL BE POSSIBLE OWING LARGELY TO CELL MERGERS SUBSEQUENT
WATER LOADING EFFECTS.
..MEAD.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...
LAT...LON 35348421 36548384 36978377 37818382 38698409 38928382
38848288 38728239 38158121 37688094 37318158 36838191
36388207 35828303 35258325 34998349 35018392 35348421
000
ACUS11 KWNS 212300
SWOMCD
SPC MCD 212300
WVZ000-VAZ000-TNZ000-KYZ000-OHZ000-NCZ000-220000-
MESOSCALE DISCUSSION 0761
NWS STORM PREDICTION CENTER NORMAN OK
0600 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN KY / WRN WV / FAR SERN OH / WRN VA / ERN TN
CONCERNING...SEVERE THUNDERSTORM WATCH 206...
VALID 212300Z - 220000Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 206
CONTINUES.
SUMMARY...THE THREAT FOR MAINLY DAMAGING WINDS CONTINUES ACROSS
REMAINING VALID PORTION OF WATCH AREA THIS EVENING.
DISCUSSION...AS OF 2240Z...REGIONAL RADAR IMAGERY INDICATED THE
LEADING EDGE OF AN EWD-MOVING MCS FROM NEAR THE OH RIVER 40 SE
LUK-20 E JKL-30 E OF TYS. THE KY SEGMENT OF THIS CONVECTIVE SYSTEM
HAS REMAINED MOST PROGRESSIVE /AROUND 30 KT/ WHERE AN EXTENSIVE
TRAILING STRATIFORM REGION AND ASSOCIATED 40-45 KT REAR-INFLOW JET
/RIJ --SEE CURRENT JKL VAD/ HAVE DEVELOPED. UPSLOPE FLOW COMBINED
WITH RIJ-ENHANCED CONVERGENCE ALONG THE LEADING EDGE OF THE SYSTEM
COLD POOL SHOULD CONTINUE TO PROMOTE FORWARD PROPAGATION --AND AN
ASSOCIATED DAMAGING WIND THREAT-- INTO WRN WV BY 22/00Z.
FARTHER S INTO ERN TN...THE MCS IS MUCH MORE FRAGMENTED AND NOT AS
PROGRESSIVE. NONETHELESS...ISOLATED OCCURRENCES OF LOCALLY DAMAGING
WINDS WILL BE POSSIBLE OWING LARGELY TO CELL MERGERS SUBSEQUENT
WATER LOADING EFFECTS.
..MEAD.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...
LAT...LON 35348421 36548384 36978377 37818382 38698409 38928382
38848288 38728239 38158121 37688094 37318158 36838191
36388207 35828303 35258325 34998349 35018392 35348421
000
ACUS11 KWNS 212300
SWOMCD
SPC MCD 212300
WVZ000-VAZ000-TNZ000-KYZ000-OHZ000-NCZ000-220000-
MESOSCALE DISCUSSION 0761
NWS STORM PREDICTION CENTER NORMAN OK
0600 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN KY / WRN WV / FAR SERN OH / WRN VA / ERN TN
CONCERNING...SEVERE THUNDERSTORM WATCH 206...
VALID 212300Z - 220000Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 206
CONTINUES.
SUMMARY...THE THREAT FOR MAINLY DAMAGING WINDS CONTINUES ACROSS
REMAINING VALID PORTION OF WATCH AREA THIS EVENING.
DISCUSSION...AS OF 2240Z...REGIONAL RADAR IMAGERY INDICATED THE
LEADING EDGE OF AN EWD-MOVING MCS FROM NEAR THE OH RIVER 40 SE
LUK-20 E JKL-30 E OF TYS. THE KY SEGMENT OF THIS CONVECTIVE SYSTEM
HAS REMAINED MOST PROGRESSIVE /AROUND 30 KT/ WHERE AN EXTENSIVE
TRAILING STRATIFORM REGION AND ASSOCIATED 40-45 KT REAR-INFLOW JET
/RIJ --SEE CURRENT JKL VAD/ HAVE DEVELOPED. UPSLOPE FLOW COMBINED
WITH RIJ-ENHANCED CONVERGENCE ALONG THE LEADING EDGE OF THE SYSTEM
COLD POOL SHOULD CONTINUE TO PROMOTE FORWARD PROPAGATION --AND AN
ASSOCIATED DAMAGING WIND THREAT-- INTO WRN WV BY 22/00Z.
FARTHER S INTO ERN TN...THE MCS IS MUCH MORE FRAGMENTED AND NOT AS
PROGRESSIVE. NONETHELESS...ISOLATED OCCURRENCES OF LOCALLY DAMAGING
WINDS WILL BE POSSIBLE OWING LARGELY TO CELL MERGERS SUBSEQUENT
WATER LOADING EFFECTS.
..MEAD.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...
LAT...LON 35348421 36548384 36978377 37818382 38698409 38928382
38848288 38728239 38158121 37688094 37318158 36838191
36388207 35828303 35258325 34998349 35018392 35348421
000
ACUS11 KWNS 212254
SWOMCD
SPC MCD 212254
LAZ000-ARZ000-TXZ000-220000-
MESOSCALE DISCUSSION 0760
NWS STORM PREDICTION CENTER NORMAN OK
0554 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN AR / NWRN LA / NERN TX
CONCERNING...TORNADO WATCH 201...205...
VALID 212254Z - 220000Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...ISOLD DAMAGING WINDS WILL BE THE PREDOMINATE THREAT THIS
EVENING OVER THE ARKLATEX REGION. LINEAR CONVECTIVE MODE IS
CONSIDERABLY LIMITING THE TORNADO THREAT.
DISCUSSION...22Z SURFACE ANALYSIS PLACES AN ARCING OUTFLOW BOUNDARY
FROM THE LOWER MS VALLEY SQUALL LINE WWD NEAR THE AR/LA BORDER AND
INTERSECTING THE GUST FRONT OVER NERN TX FROM THE TX/AR QLCS. THE
AREA N OF THE OUTFLOW BOUNDARY HAS STABILIZED APPRECIABLY AT THE
SURFACE BUT IS STILL SUPPORTIVE OF STRONGER GUSTS PENETRATING THE
SURFACE...ESPECIALLY IN CLOSER PROXIMITY TO THE OUTFLOW BOUNDARY
WHERE THE COLD POOL DEPTH IS MORE SHALLOW. A RECENTLY MEASURED 44
KT ASOS GUST AT KTXK ILLUSTRATES THIS WELL.
FARTHER SOUTH...THE QLCS CHARACTERISTICS OVER NERN TX SHOW A LOOSELY
ORGANIZED STRUCTURE BUT THE GUST FRONT HAS SURGED WELL AHEAD OF THE
DEEPER UPDRAFTS LOCATED WITHIN THE MAIN CONVECTIVE BAND. AS
SUCH...EXPECTING THE TORNADO RISK NEAR THE QLCS-OUTFLOW BOUNDARY
INTERSECTION TO REMAIN QUITE LOW UNLESS DEEPER UPDRAFTS CAN BETTER
PHASE WITH THE LEADING EDGE OF THE COLD POOL AND STRETCH/AUGMENT LOW
LEVEL VORTICITY NEAR THIS BOUNDARY. THE AREA AHEAD OF THE QLCS OVER
E-CNTRL TX EWD INTO NWRN LA LIKELY POSES THE GREATEST POTENTIAL FOR
ISOLD STRAIGHT-LINE WIND DAMAGE GIVEN THE UNDISTURBED MOIST/UNSTABLE
BOUNDARY LAYER.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...FWD...
LAT...LON 33989377 33739233 32589216 32039287 31629474 31589588
31859638 32669580 33989377
000
ACUS11 KWNS 212254
SWOMCD
SPC MCD 212254
LAZ000-ARZ000-TXZ000-220000-
MESOSCALE DISCUSSION 0760
NWS STORM PREDICTION CENTER NORMAN OK
0554 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN AR / NWRN LA / NERN TX
CONCERNING...TORNADO WATCH 201...205...
VALID 212254Z - 220000Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...ISOLD DAMAGING WINDS WILL BE THE PREDOMINATE THREAT THIS
EVENING OVER THE ARKLATEX REGION. LINEAR CONVECTIVE MODE IS
CONSIDERABLY LIMITING THE TORNADO THREAT.
DISCUSSION...22Z SURFACE ANALYSIS PLACES AN ARCING OUTFLOW BOUNDARY
FROM THE LOWER MS VALLEY SQUALL LINE WWD NEAR THE AR/LA BORDER AND
INTERSECTING THE GUST FRONT OVER NERN TX FROM THE TX/AR QLCS. THE
AREA N OF THE OUTFLOW BOUNDARY HAS STABILIZED APPRECIABLY AT THE
SURFACE BUT IS STILL SUPPORTIVE OF STRONGER GUSTS PENETRATING THE
SURFACE...ESPECIALLY IN CLOSER PROXIMITY TO THE OUTFLOW BOUNDARY
WHERE THE COLD POOL DEPTH IS MORE SHALLOW. A RECENTLY MEASURED 44
KT ASOS GUST AT KTXK ILLUSTRATES THIS WELL.
FARTHER SOUTH...THE QLCS CHARACTERISTICS OVER NERN TX SHOW A LOOSELY
ORGANIZED STRUCTURE BUT THE GUST FRONT HAS SURGED WELL AHEAD OF THE
DEEPER UPDRAFTS LOCATED WITHIN THE MAIN CONVECTIVE BAND. AS
SUCH...EXPECTING THE TORNADO RISK NEAR THE QLCS-OUTFLOW BOUNDARY
INTERSECTION TO REMAIN QUITE LOW UNLESS DEEPER UPDRAFTS CAN BETTER
PHASE WITH THE LEADING EDGE OF THE COLD POOL AND STRETCH/AUGMENT LOW
LEVEL VORTICITY NEAR THIS BOUNDARY. THE AREA AHEAD OF THE QLCS OVER
E-CNTRL TX EWD INTO NWRN LA LIKELY POSES THE GREATEST POTENTIAL FOR
ISOLD STRAIGHT-LINE WIND DAMAGE GIVEN THE UNDISTURBED MOIST/UNSTABLE
BOUNDARY LAYER.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...FWD...
LAT...LON 33989377 33739233 32589216 32039287 31629474 31589588
31859638 32669580 33989377
000
ACUS11 KWNS 212254
SWOMCD
SPC MCD 212254
LAZ000-ARZ000-TXZ000-220000-
MESOSCALE DISCUSSION 0760
NWS STORM PREDICTION CENTER NORMAN OK
0554 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN AR / NWRN LA / NERN TX
CONCERNING...TORNADO WATCH 201...205...
VALID 212254Z - 220000Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...ISOLD DAMAGING WINDS WILL BE THE PREDOMINATE THREAT THIS
EVENING OVER THE ARKLATEX REGION. LINEAR CONVECTIVE MODE IS
CONSIDERABLY LIMITING THE TORNADO THREAT.
DISCUSSION...22Z SURFACE ANALYSIS PLACES AN ARCING OUTFLOW BOUNDARY
FROM THE LOWER MS VALLEY SQUALL LINE WWD NEAR THE AR/LA BORDER AND
INTERSECTING THE GUST FRONT OVER NERN TX FROM THE TX/AR QLCS. THE
AREA N OF THE OUTFLOW BOUNDARY HAS STABILIZED APPRECIABLY AT THE
SURFACE BUT IS STILL SUPPORTIVE OF STRONGER GUSTS PENETRATING THE
SURFACE...ESPECIALLY IN CLOSER PROXIMITY TO THE OUTFLOW BOUNDARY
WHERE THE COLD POOL DEPTH IS MORE SHALLOW. A RECENTLY MEASURED 44
KT ASOS GUST AT KTXK ILLUSTRATES THIS WELL.
FARTHER SOUTH...THE QLCS CHARACTERISTICS OVER NERN TX SHOW A LOOSELY
ORGANIZED STRUCTURE BUT THE GUST FRONT HAS SURGED WELL AHEAD OF THE
DEEPER UPDRAFTS LOCATED WITHIN THE MAIN CONVECTIVE BAND. AS
SUCH...EXPECTING THE TORNADO RISK NEAR THE QLCS-OUTFLOW BOUNDARY
INTERSECTION TO REMAIN QUITE LOW UNLESS DEEPER UPDRAFTS CAN BETTER
PHASE WITH THE LEADING EDGE OF THE COLD POOL AND STRETCH/AUGMENT LOW
LEVEL VORTICITY NEAR THIS BOUNDARY. THE AREA AHEAD OF THE QLCS OVER
E-CNTRL TX EWD INTO NWRN LA LIKELY POSES THE GREATEST POTENTIAL FOR
ISOLD STRAIGHT-LINE WIND DAMAGE GIVEN THE UNDISTURBED MOIST/UNSTABLE
BOUNDARY LAYER.
..SMITH.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...FWD...
LAT...LON 33989377 33739233 32589216 32039287 31629474 31589588
31859638 32669580 33989377
000
ACUS11 KWNS 212209
SWOMCD
SPC MCD 212209
RIZ000-CTZ000-NYZ000-212315-
MESOSCALE DISCUSSION 0759
NWS STORM PREDICTION CENTER NORMAN OK
0509 PM CDT TUE MAY 21 2013
AREAS AFFECTED...SRN PARTS OF CT AND RI
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 212209Z - 212315Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THE THREAT FOR ISOLATED SEVERE WEATHER WILL INCREASE BY
21/23-22/00Z. LARGE HAIL AND LOCALLY DAMAGING WIND GUSTS WILL BE
POSSIBLE. THE LIMITED AREAL COVERAGE OF THE THREAT WILL LIKELY
PRECLUDE A WATCH ISSUANCE.
DISCUSSION...AS OF 22Z...REGIONAL RADAR IMAGERY INDICATED A WNW-ESE
ORIENTED BAND OF STORMS /WITH EMBEDDED SUPERCELLS/ FROM COLUMBIA
COUNTY NY TO WORCESTER COUNTY MA WITH A GENERAL STORM MOTION OF
310/20 KT. THESE STORMS HAVE A HISTORY OF PRODUCING LARGE HAIL AND
OBSERVED SEVERE WIND GUSTS WHILE PROGRESSING ALONG AND S OF A
SURFACE BAROCLINIC ZONE THAT EXTENDS FROM N OF UCA-ALB-N OF BAF-SW
OF PVD. THE AIR MASS ALONG AND S OF THIS BOUNDARY IS WARM AND QUITE
MOIST WHICH HAS RESULTED IN A MODERATELY UNSTABLE ENVIRONMENT. WHEN
COUPLED WITH A VERTICALLY VEERING WIND PROFILE AND 30-35 KT OF
DEEP-LAYER SHEAR...THE SETUP SHOULD SUSTAIN ONGOING STORMS WHICH MAY
DEVELOP TO THE SOUTH OF SEVERE THUNDERSTORM WATCHES 203 AND 204
WITHIN THE NEXT HOUR OR TWO. GIVEN THE INFLUENCE OF THE MARINE PBL
WHICH HAS DEVELOPED INLAND...THE SEVERE WEATHER THREAT IS EXPECTED
TO REMAIN ISOLATED IN NATURE AND AN ADDITIONAL WATCH IS NOT
ANTICIPATED.
..MEAD/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...OKX...
LAT...LON 41387350 41557302 41637232 41647197 41517157 41207140
41127189 41097286 41177346 41387350
000
ACUS11 KWNS 212209
SWOMCD
SPC MCD 212209
RIZ000-CTZ000-NYZ000-212315-
MESOSCALE DISCUSSION 0759
NWS STORM PREDICTION CENTER NORMAN OK
0509 PM CDT TUE MAY 21 2013
AREAS AFFECTED...SRN PARTS OF CT AND RI
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 212209Z - 212315Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THE THREAT FOR ISOLATED SEVERE WEATHER WILL INCREASE BY
21/23-22/00Z. LARGE HAIL AND LOCALLY DAMAGING WIND GUSTS WILL BE
POSSIBLE. THE LIMITED AREAL COVERAGE OF THE THREAT WILL LIKELY
PRECLUDE A WATCH ISSUANCE.
DISCUSSION...AS OF 22Z...REGIONAL RADAR IMAGERY INDICATED A WNW-ESE
ORIENTED BAND OF STORMS /WITH EMBEDDED SUPERCELLS/ FROM COLUMBIA
COUNTY NY TO WORCESTER COUNTY MA WITH A GENERAL STORM MOTION OF
310/20 KT. THESE STORMS HAVE A HISTORY OF PRODUCING LARGE HAIL AND
OBSERVED SEVERE WIND GUSTS WHILE PROGRESSING ALONG AND S OF A
SURFACE BAROCLINIC ZONE THAT EXTENDS FROM N OF UCA-ALB-N OF BAF-SW
OF PVD. THE AIR MASS ALONG AND S OF THIS BOUNDARY IS WARM AND QUITE
MOIST WHICH HAS RESULTED IN A MODERATELY UNSTABLE ENVIRONMENT. WHEN
COUPLED WITH A VERTICALLY VEERING WIND PROFILE AND 30-35 KT OF
DEEP-LAYER SHEAR...THE SETUP SHOULD SUSTAIN ONGOING STORMS WHICH MAY
DEVELOP TO THE SOUTH OF SEVERE THUNDERSTORM WATCHES 203 AND 204
WITHIN THE NEXT HOUR OR TWO. GIVEN THE INFLUENCE OF THE MARINE PBL
WHICH HAS DEVELOPED INLAND...THE SEVERE WEATHER THREAT IS EXPECTED
TO REMAIN ISOLATED IN NATURE AND AN ADDITIONAL WATCH IS NOT
ANTICIPATED.
..MEAD/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...OKX...
LAT...LON 41387350 41557302 41637232 41647197 41517157 41207140
41127189 41097286 41177346 41387350
000
ACUS11 KWNS 212209
SWOMCD
SPC MCD 212209
RIZ000-CTZ000-NYZ000-212315-
MESOSCALE DISCUSSION 0759
NWS STORM PREDICTION CENTER NORMAN OK
0509 PM CDT TUE MAY 21 2013
AREAS AFFECTED...SRN PARTS OF CT AND RI
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 212209Z - 212315Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...THE THREAT FOR ISOLATED SEVERE WEATHER WILL INCREASE BY
21/23-22/00Z. LARGE HAIL AND LOCALLY DAMAGING WIND GUSTS WILL BE
POSSIBLE. THE LIMITED AREAL COVERAGE OF THE THREAT WILL LIKELY
PRECLUDE A WATCH ISSUANCE.
DISCUSSION...AS OF 22Z...REGIONAL RADAR IMAGERY INDICATED A WNW-ESE
ORIENTED BAND OF STORMS /WITH EMBEDDED SUPERCELLS/ FROM COLUMBIA
COUNTY NY TO WORCESTER COUNTY MA WITH A GENERAL STORM MOTION OF
310/20 KT. THESE STORMS HAVE A HISTORY OF PRODUCING LARGE HAIL AND
OBSERVED SEVERE WIND GUSTS WHILE PROGRESSING ALONG AND S OF A
SURFACE BAROCLINIC ZONE THAT EXTENDS FROM N OF UCA-ALB-N OF BAF-SW
OF PVD. THE AIR MASS ALONG AND S OF THIS BOUNDARY IS WARM AND QUITE
MOIST WHICH HAS RESULTED IN A MODERATELY UNSTABLE ENVIRONMENT. WHEN
COUPLED WITH A VERTICALLY VEERING WIND PROFILE AND 30-35 KT OF
DEEP-LAYER SHEAR...THE SETUP SHOULD SUSTAIN ONGOING STORMS WHICH MAY
DEVELOP TO THE SOUTH OF SEVERE THUNDERSTORM WATCHES 203 AND 204
WITHIN THE NEXT HOUR OR TWO. GIVEN THE INFLUENCE OF THE MARINE PBL
WHICH HAS DEVELOPED INLAND...THE SEVERE WEATHER THREAT IS EXPECTED
TO REMAIN ISOLATED IN NATURE AND AN ADDITIONAL WATCH IS NOT
ANTICIPATED.
..MEAD/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...OKX...
LAT...LON 41387350 41557302 41637232 41647197 41517157 41207140
41127189 41097286 41177346 41387350
000
ACUS11 KWNS 212155
SWOMCD
SPC MCD 212155
TXZ000-212330-
MESOSCALE DISCUSSION 0758
NWS STORM PREDICTION CENTER NORMAN OK
0455 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF E-CNTRL AND SERN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 212155Z - 212330Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...A STRONG TO SEVERE STORM THREAT WILL PROBABLY MOVE INTO
PORTIONS OF E-CNTRL AND SERN TX THIS EVENING/TONIGHT. ALTHOUGH
ISOLD LARGE HAIL/DMGG WINDS WILL BE THE PRIMARY THREATS...A TORNADO
IS ALSO POSSIBLE.
DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SQUALL LINE FROM WRN AR
SWWD INTO N-CNTRL TX WITH SOME CELLULAR STORMS /INCLUDING THE BELL
COUNTY SUPERCELL/ ON THE SRN FRINGE OF THE LINE OF STORMS.
SUBJECTIVE SURFACE MESOANALYSIS SHOWS THE N-CNTRL TX PORTION OF THE
LINE JUXTAPOSED WITH THE COLD FRONT AND THEN EXTENDING SWWD OVER THE
TX HILL COUNTRY. FARTHER E...A PRE-FRONTAL CONFLUENCE ZONE HAS
SERVED TO PREFERENTIALLY FAVOR CELLULAR DEVELOPMENT ON THE SRN
PORTION OF THE LINE WITH THE FRONTAL LIFT DISPLACED 1-2 COUNTIES
WEST. SURFACE TEMPS HAVE WARMED TO NEAR 90 DEG F WITH DEWPOINTS
AROUND 70 DEG F...CONTRIBUTING TO A VERY UNSTABLE AIRMASS /2500-3000
MLCAPE PER OBJECTIVE ANALYSIS/. THE KGRK VWP SHOWS 0-6 KM SHEAR /40
KT/ MORE THAN SUFFICIENT FOR ORGANIZED LINE SEGMENTS AND SUPERCELLS.
ALTHOUGH LOW LEVEL SHEAR IS MODEST /100 M2/S2 0-1 KM SRH/...A
TORNADO IS POSSIBLE...ESPECIALLY IF A MORE FAVORABLE CONVECTIVE MODE
CAN BE MAINTAINED AS STORMS MOVE INTO THE DISCUSSION AREA.
..SMITH/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...FWD...EWX...
LAT...LON 30589692 31549540 30969430 30429698 30589692
000
ACUS11 KWNS 212155
SWOMCD
SPC MCD 212155
TXZ000-212330-
MESOSCALE DISCUSSION 0758
NWS STORM PREDICTION CENTER NORMAN OK
0455 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF E-CNTRL AND SERN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 212155Z - 212330Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...A STRONG TO SEVERE STORM THREAT WILL PROBABLY MOVE INTO
PORTIONS OF E-CNTRL AND SERN TX THIS EVENING/TONIGHT. ALTHOUGH
ISOLD LARGE HAIL/DMGG WINDS WILL BE THE PRIMARY THREATS...A TORNADO
IS ALSO POSSIBLE.
DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SQUALL LINE FROM WRN AR
SWWD INTO N-CNTRL TX WITH SOME CELLULAR STORMS /INCLUDING THE BELL
COUNTY SUPERCELL/ ON THE SRN FRINGE OF THE LINE OF STORMS.
SUBJECTIVE SURFACE MESOANALYSIS SHOWS THE N-CNTRL TX PORTION OF THE
LINE JUXTAPOSED WITH THE COLD FRONT AND THEN EXTENDING SWWD OVER THE
TX HILL COUNTRY. FARTHER E...A PRE-FRONTAL CONFLUENCE ZONE HAS
SERVED TO PREFERENTIALLY FAVOR CELLULAR DEVELOPMENT ON THE SRN
PORTION OF THE LINE WITH THE FRONTAL LIFT DISPLACED 1-2 COUNTIES
WEST. SURFACE TEMPS HAVE WARMED TO NEAR 90 DEG F WITH DEWPOINTS
AROUND 70 DEG F...CONTRIBUTING TO A VERY UNSTABLE AIRMASS /2500-3000
MLCAPE PER OBJECTIVE ANALYSIS/. THE KGRK VWP SHOWS 0-6 KM SHEAR /40
KT/ MORE THAN SUFFICIENT FOR ORGANIZED LINE SEGMENTS AND SUPERCELLS.
ALTHOUGH LOW LEVEL SHEAR IS MODEST /100 M2/S2 0-1 KM SRH/...A
TORNADO IS POSSIBLE...ESPECIALLY IF A MORE FAVORABLE CONVECTIVE MODE
CAN BE MAINTAINED AS STORMS MOVE INTO THE DISCUSSION AREA.
..SMITH/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...FWD...EWX...
LAT...LON 30589692 31549540 30969430 30429698 30589692
000
ACUS11 KWNS 212155
SWOMCD
SPC MCD 212155
TXZ000-212330-
MESOSCALE DISCUSSION 0758
NWS STORM PREDICTION CENTER NORMAN OK
0455 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF E-CNTRL AND SERN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 212155Z - 212330Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...A STRONG TO SEVERE STORM THREAT WILL PROBABLY MOVE INTO
PORTIONS OF E-CNTRL AND SERN TX THIS EVENING/TONIGHT. ALTHOUGH
ISOLD LARGE HAIL/DMGG WINDS WILL BE THE PRIMARY THREATS...A TORNADO
IS ALSO POSSIBLE.
DISCUSSION...RADAR MOSAIC SHOWS AN EXTENSIVE SQUALL LINE FROM WRN AR
SWWD INTO N-CNTRL TX WITH SOME CELLULAR STORMS /INCLUDING THE BELL
COUNTY SUPERCELL/ ON THE SRN FRINGE OF THE LINE OF STORMS.
SUBJECTIVE SURFACE MESOANALYSIS SHOWS THE N-CNTRL TX PORTION OF THE
LINE JUXTAPOSED WITH THE COLD FRONT AND THEN EXTENDING SWWD OVER THE
TX HILL COUNTRY. FARTHER E...A PRE-FRONTAL CONFLUENCE ZONE HAS
SERVED TO PREFERENTIALLY FAVOR CELLULAR DEVELOPMENT ON THE SRN
PORTION OF THE LINE WITH THE FRONTAL LIFT DISPLACED 1-2 COUNTIES
WEST. SURFACE TEMPS HAVE WARMED TO NEAR 90 DEG F WITH DEWPOINTS
AROUND 70 DEG F...CONTRIBUTING TO A VERY UNSTABLE AIRMASS /2500-3000
MLCAPE PER OBJECTIVE ANALYSIS/. THE KGRK VWP SHOWS 0-6 KM SHEAR /40
KT/ MORE THAN SUFFICIENT FOR ORGANIZED LINE SEGMENTS AND SUPERCELLS.
ALTHOUGH LOW LEVEL SHEAR IS MODEST /100 M2/S2 0-1 KM SRH/...A
TORNADO IS POSSIBLE...ESPECIALLY IF A MORE FAVORABLE CONVECTIVE MODE
CAN BE MAINTAINED AS STORMS MOVE INTO THE DISCUSSION AREA.
..SMITH/CORFIDI.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...FWD...EWX...
LAT...LON 30589692 31549540 30969430 30429698 30589692
000
ACUS11 KWNS 212037
SWOMCD
SPC MCD 212037
RIZ000-MAZ000-CTZ000-NHZ000-VTZ000-NYZ000-212130-
MESOSCALE DISCUSSION 0757
NWS STORM PREDICTION CENTER NORMAN OK
0337 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PORTIONS OF NY...SRN NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 203...204...
VALID 212037Z - 212130Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
203...204...CONTINUES.
SUMMARY...ISOLATED THREAT FOR LARGE HAIL AND DMGG WIND GUSTS WILL
CONTINUE INTO THE EARLY EVENING WITHIN A W-E CORRIDOR INVOF A
QUASI-STATIONARY FRONT.
DISCUSSION...RADAR TRENDS SHOW PULSING ISOLATED TSTMS ACROSS MUCH OF
WRN/CNTRL NY...ALONG A QUASI-STATIONARY FRONT DRAPED W-E FROM
APPROXIMATELY 10 N BUF TO 10 SW ORH AS OF 20Z. MORE
ORGANIZED/SUSTAINED CONVECTION HAS BEEN NOTED ACROSS ERN NY INTO WRN
MA...E OF THE HUDSON VALLEY...WHERE A STORM SPLIT OCCURRED WITHIN
THE PAST COUPLE HRS. GIVEN STRONG HEATING S OF THE BOUNDARY
/TEMPERATURES APPROACHING 90 F/ MAINTAINING A VERY UNSTABLE
ENVIRONMENT...CONVECTION APPEARS LIKELY TO PERSIST AND MAINTAIN
INTENSITY INTO THE EARLY EVENING. HOWEVER...COVERAGE SHOULD CONTINUE
TO GENERALLY REMAIN ISOLATED/SEMI-DISCRETE...OWING TO WEAK FORCING
FOR ASCENT AND CONVERGENCE ALONG THE BOUNDARY.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...ALY...BGM...BUF...
LAT...LON 41777440 41627477 41887496 42027534 42067957 42597926
43557882 43537648 43337531 43877492 43847452 43587359
43297334 42967226 42377193 41797158 41707152 41777440
000
ACUS11 KWNS 212037
SWOMCD
SPC MCD 212037
RIZ000-MAZ000-CTZ000-NHZ000-VTZ000-NYZ000-212130-
MESOSCALE DISCUSSION 0757
NWS STORM PREDICTION CENTER NORMAN OK
0337 PM CDT TUE MAY 21 2013
AREAS AFFECTED...PORTIONS OF NY...SRN NEW ENGLAND
CONCERNING...SEVERE THUNDERSTORM WATCH 203...204...
VALID 212037Z - 212130Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
203...204...CONTINUES.
SUMMARY...ISOLATED THREAT FOR LARGE HAIL AND DMGG WIND GUSTS WILL
CONTINUE INTO THE EARLY EVENING WITHIN A W-E CORRIDOR INVOF A
QUASI-STATIONARY FRONT.
DISCUSSION...RADAR TRENDS SHOW PULSING ISOLATED TSTMS ACROSS MUCH OF
WRN/CNTRL NY...ALONG A QUASI-STATIONARY FRONT DRAPED W-E FROM
APPROXIMATELY 10 N BUF TO 10 SW ORH AS OF 20Z. MORE
ORGANIZED/SUSTAINED CONVECTION HAS BEEN NOTED ACROSS ERN NY INTO WRN
MA...E OF THE HUDSON VALLEY...WHERE A STORM SPLIT OCCURRED WITHIN
THE PAST COUPLE HRS. GIVEN STRONG HEATING S OF THE BOUNDARY
/TEMPERATURES APPROACHING 90 F/ MAINTAINING A VERY UNSTABLE
ENVIRONMENT...CONVECTION APPEARS LIKELY TO PERSIST AND MAINTAIN
INTENSITY INTO THE EARLY EVENING. HOWEVER...COVERAGE SHOULD CONTINUE
TO GENERALLY REMAIN ISOLATED/SEMI-DISCRETE...OWING TO WEAK FORCING
FOR ASCENT AND CONVERGENCE ALONG THE BOUNDARY.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...ALY...BGM...BUF...
LAT...LON 41777440 41627477 41887496 42027534 42067957 42597926
43557882 43537648 43337531 43877492 43847452 43587359
43297334 42967226 42377193 41797158 41707152 41777440
000
ACUS11 KWNS 212018
SWOMCD
SPC MCD 212018
LAZ000-ARZ000-TXZ000-OKZ000-212145-
MESOSCALE DISCUSSION 0756
NWS STORM PREDICTION CENTER NORMAN OK
0318 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL INTO THE ARKLATEX
CONCERNING...TORNADO WATCH 201...205...
VALID 212018Z - 212145Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...A LINE OF SEVERE STORMS SHOULD CONTINUE TO BECOME BETTER
ORGANIZED WITH WIDESPREAD DAMAGING WINDS LIKELY ACROSS NERN TX.
OTHER STORMS SHOULD INCREASE IN COVERAGE FARTHER S ALONG OR JUST
AHEAD OF THE COLD FRONT...WITH LARGE HAIL AND DAMAGING WINDS AND
PERHAPS AN ISOLATED TORNADO.
DISCUSSION...SEVERE STORMS CURRENTLY EXTEND FROM NEAR THE RED RIVER
SWWD TOWARD THE DALLAS AREA...WITH A GENERAL UPSWING IN INTENSITY
NOTED. WITH AMPLE INSTABILITY AHEAD OF THESE STORMS...THIS TREND
SHOULD CONTINUE. GIVEN LINEAR STORM MODE...DAMAGING WINDS ARE LIKELY
TO THE S...SUPERCELLS WERE RAPIDLY DEVELOPING NEAR THE SRN BORDER OF
TORNADO WATCH 201...AND SHOULD CONTINUE INTO THE WATCH. THESE CELLS
WILL HAVE A DISTINCT LARGE HAIL THREAT...AND COULD PRODUCE A TORNADO
AS WELL BEFORE THE COLD FRONT OVERTAKES THEM. IF A SWD TREND IN
DEVELOPMENT PERSISTS...NRN PORTIONS OF THE HOUSTON CWA MAY NEED TO
BE INCLUDED IN A WATCH.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...JAN...LZK...SHV...TSA...HGX...FWD...OUN...EWX...
SJT...
LAT...LON 31569202 31449527 31779528 30360002 30890004 31129942
31559846 32179746 32709688 33239668 34179658 34549521
34219522 34329201 31569202
000
ACUS11 KWNS 212018
SWOMCD
SPC MCD 212018
LAZ000-ARZ000-TXZ000-OKZ000-212145-
MESOSCALE DISCUSSION 0756
NWS STORM PREDICTION CENTER NORMAN OK
0318 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL INTO THE ARKLATEX
CONCERNING...TORNADO WATCH 201...205...
VALID 212018Z - 212145Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...A LINE OF SEVERE STORMS SHOULD CONTINUE TO BECOME BETTER
ORGANIZED WITH WIDESPREAD DAMAGING WINDS LIKELY ACROSS NERN TX.
OTHER STORMS SHOULD INCREASE IN COVERAGE FARTHER S ALONG OR JUST
AHEAD OF THE COLD FRONT...WITH LARGE HAIL AND DAMAGING WINDS AND
PERHAPS AN ISOLATED TORNADO.
DISCUSSION...SEVERE STORMS CURRENTLY EXTEND FROM NEAR THE RED RIVER
SWWD TOWARD THE DALLAS AREA...WITH A GENERAL UPSWING IN INTENSITY
NOTED. WITH AMPLE INSTABILITY AHEAD OF THESE STORMS...THIS TREND
SHOULD CONTINUE. GIVEN LINEAR STORM MODE...DAMAGING WINDS ARE LIKELY
TO THE S...SUPERCELLS WERE RAPIDLY DEVELOPING NEAR THE SRN BORDER OF
TORNADO WATCH 201...AND SHOULD CONTINUE INTO THE WATCH. THESE CELLS
WILL HAVE A DISTINCT LARGE HAIL THREAT...AND COULD PRODUCE A TORNADO
AS WELL BEFORE THE COLD FRONT OVERTAKES THEM. IF A SWD TREND IN
DEVELOPMENT PERSISTS...NRN PORTIONS OF THE HOUSTON CWA MAY NEED TO
BE INCLUDED IN A WATCH.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...JAN...LZK...SHV...TSA...HGX...FWD...OUN...EWX...
SJT...
LAT...LON 31569202 31449527 31779528 30360002 30890004 31129942
31559846 32179746 32709688 33239668 34179658 34549521
34219522 34329201 31569202
000
ACUS11 KWNS 212018
SWOMCD
SPC MCD 212018
LAZ000-ARZ000-TXZ000-OKZ000-212145-
MESOSCALE DISCUSSION 0756
NWS STORM PREDICTION CENTER NORMAN OK
0318 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL INTO THE ARKLATEX
CONCERNING...TORNADO WATCH 201...205...
VALID 212018Z - 212145Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201...205...CONTINUES.
SUMMARY...A LINE OF SEVERE STORMS SHOULD CONTINUE TO BECOME BETTER
ORGANIZED WITH WIDESPREAD DAMAGING WINDS LIKELY ACROSS NERN TX.
OTHER STORMS SHOULD INCREASE IN COVERAGE FARTHER S ALONG OR JUST
AHEAD OF THE COLD FRONT...WITH LARGE HAIL AND DAMAGING WINDS AND
PERHAPS AN ISOLATED TORNADO.
DISCUSSION...SEVERE STORMS CURRENTLY EXTEND FROM NEAR THE RED RIVER
SWWD TOWARD THE DALLAS AREA...WITH A GENERAL UPSWING IN INTENSITY
NOTED. WITH AMPLE INSTABILITY AHEAD OF THESE STORMS...THIS TREND
SHOULD CONTINUE. GIVEN LINEAR STORM MODE...DAMAGING WINDS ARE LIKELY
TO THE S...SUPERCELLS WERE RAPIDLY DEVELOPING NEAR THE SRN BORDER OF
TORNADO WATCH 201...AND SHOULD CONTINUE INTO THE WATCH. THESE CELLS
WILL HAVE A DISTINCT LARGE HAIL THREAT...AND COULD PRODUCE A TORNADO
AS WELL BEFORE THE COLD FRONT OVERTAKES THEM. IF A SWD TREND IN
DEVELOPMENT PERSISTS...NRN PORTIONS OF THE HOUSTON CWA MAY NEED TO
BE INCLUDED IN A WATCH.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...JAN...LZK...SHV...TSA...HGX...FWD...OUN...EWX...
SJT...
LAT...LON 31569202 31449527 31779528 30360002 30890004 31129942
31559846 32179746 32709688 33239668 34179658 34549521
34219522 34329201 31569202
000
ACUS01 KWNS 211959
SWODY1
SPC AC 211958
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT TUE MAY 21 2013
VALID 212000Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER NORTH CENTRAL AND NERN
TX...SERN OK...SRN AR...AND NRN LA...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN PLAINS ACROSS THE
TN VALLEY...LOWER GREAT LAKES...AND THE NERN STATES...
...SRN PLAINS INTO THE TN VALLEY...
A SERIES OF LINEAR CONVECTIVE SYSTEMS ARE MOVING EWD FROM SERN
OK/NORTH CENTRAL TX INTO AR AND KY/TN...IN ADVANCE OF AN UPPER
VORTICITY MAX/SHORT WAVE TROUGH LOCATED OVER THE TX PANHANDLE.
STRONG DIABATIC HEATING HAS OCCURRED SOUTH OF A CONVECTIVE BOUNDARY
ARCING FROM EAST CENTRAL AR ACROSS SRN AR INTO NORTH CENTRAL
TX...AND WITH STEEP LAPSE RATES /REF 18Z FWD AND 19Z SHV SPECIAL
RAOBS/ IN PLACE COUPLED WITH SURFACE DEW POINTS AROUND 70F...THE
ENVIRONMENT HAS BECOME VERY UNSTABLE WITH SBCAPE NEAR 3500 J/KG.
VISIBLE IMAGERY SHOWS CLOUD STREETS OVER ERN TX AND LA FEEDING NWD
TOWARD THE THERMAL BOUNDARY INDICATING A FAVORABLE MOISTURE
TRANSPORT INTO THE AREA. LOW-LEVEL CONVERGENCE IS FOCUSED IN THREE
AREAS: 1) NEAR A SURFACE LOW OVER THE METROPLEX...2) ALONG THE COLD
FRONT EXTENDING SWWD INTO THE HILL COUNTRY...AND 3) ALONG THE
EAST/WEST CONVECTIVE BOUNDARY ACROSS NERN TX/SWRN AR. STORMS ARE
EXPECTED TO INTENSIFY THE REMAINDER OF THIS AFTERNOON INTO THE
EVENING AS THE UPPER SYSTEM AND SURFACE LOW MOVE EWD...WITH
POTENTIAL FOR SUPERCELLS AND BOWING LINE SEGMENTS. 12Z NSSL WRF-ARW
AND RECENT HRRR MODELS INDICATE DEVELOPMENT OF LONG-LIVED BOWING
QLCS/S MOVING EWD ACROSS NERN TX INTO SRN AR AND NRN LA...AND
ENVIRONMENT APPEARS SUPPORTIVE OF THIS EVENT. THUS...WILL MAINTAIN
POTENTIAL FOR VERY LARGE HAIL AND SEVERAL TORNADOES /INCLUDING ONE
OR TWO STRONG TORNADOES/ ASSOCIATED PRIMARILY WITH ANY SUPERCELLS
THAT FORM...ALONG WITH WIDESPREAD SIGNIFICANT WIND DAMAGE GIVEN THE
POTENTIAL FOR A PROGRESSIVE BOWING CONVECTIVE SYSTEM TO FORM WITHIN
THE NEXT 1-2 HRS.
ELSEWHERE FROM THE MID-SOUTH INTO THE TN VALLEY...ADDITIONAL LINEAR
CONVECTIVE SYSTEMS OVER ERN AR AND SRN KY/MIDDLE TN ARE LIKELY TO
PROGRESS EWD/NEWD OVER THE NEXT SEVERAL HOURS...WHILE NEW
STRONG/SEVERE STORMS HAVE DEVELOPED ALONG THE TRAILING OUTFLOW
BOUNDARY OVER FAR NRN MS. GIVEN THE DEGREE OF INSTABILITY WITH CAPE
OF 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40 KT...A THREAT FOR
DAMAGING WINDS AND HAIL WILL CONTINUE WITH THESE STORMS.
..WEISS.. 05/21/2013
.PREV DISCUSSION... /ISSUED 1128 AM CDT TUE MAY 21 2013/
...SUBSTANTIAL SEVERE WEATHER EXPECTED ACROSS N-CNTRL TX TO THE
ARKLATEX THIS AFTERNOON AND EVENING...
..SRN PLAINS TO LOWER MS VALLEY...
SIGNIFICANT SEVERE WEATHER EPISODE INITIALLY UNFOLDING ACROSS THE
RED RIVER WITH SUPERCELLS PRODUCING LARGE HAIL ALONG AND N OF THE
COMPOSITE OUTFLOW/COLD FRONT PUSHING SWD FROM THE BIG COUNTRY TO FAR
SERN OK AHEAD OF A WELL-DEFINED SHORTWAVE TROUGH OVER THE SRN HIGH
PLAINS. AIR MASS S OF THE BOUNDARY IS BECOMING STRONGLY UNSTABLE AS
GRADUAL SURFACE HEATING CONTINUES AMIDST LOWEST 100 MB MEAN MIXING
RATIOS OF 14-17 G/KG AND 700-500 MB LAPSE RATES OF 8 TO 9.5 DEG C/KM
SAMPLED IN ALL REGIONAL 12Z RAOBS. AS MLCIN IS MINIMIZED ALONG THE
DRYLINE MIXING EWD ACROSS THE EDWARDS PLATEAU...ADDITIONAL SUPERCELL
DEVELOPMENT IS ANTICIPATED WITH SWD EXTENT.
A BELT OF 50-60 KT MID-LEVEL SWLYS ATTENDANT TO THE COMPACT
SHORTWAVE TROUGH WILL PROMOTE RISKS FOR ALL SEVERE TYPES /SOME OF
WHICH WILL BE SIGNIFICANT/. MORNING CONVECTION-ALLOWING WRF AND HRRR
SIMULATIONS ARE INSISTENT THAT UPSCALE GROWTH WILL OCCUR THROUGHOUT
THE AFTERNOON. GIVEN THE DEGREE OF INSTABILITY...BUOYANCY AND
SHEAR...SETUP MAY YIELD A DERECHO ACCELERATING EWD TOWARDS THE
ARKLATEX REGION BY EARLY EVENING. HERE TOO...THE STRONGEST LOW-LEVEL
S/SWLYS WILL REMAIN...PROMOTING EMBEDDED MESOVORTICES CAPABLE OF
PRODUCING A COUPLE OF SIGNIFICANT TORNADOES. OTHERWISE...POTENTIAL
DOES EXIST FOR WIDESPREAD/DESTRUCTIVE DAMAGING WIND GUSTS.
...TN VALLEY TO THE LOWER GREAT LAKES/NORTHEAST...
A BROAD AREA OF ORGANIZED SEVERE POTENTIAL IS EXPECTED ALONG THE ERN
EXTENT OF THE ELEVATED MIXED LAYER PLUME SAMPLED IN 12Z RAOBS. WITH
ROBUST HEATING...MODERATE TO STRONG INSTABILITY IS ANTICIPATED...BUT
MOST OF THE REGION WILL REMAIN ON THE FRINGE OF SUFFICIENT
DEEP-LAYER SHEAR FOR SUPERCELLS. THREE ZONES OF FOCUS FOR SUSTAINED
CONVECTION ARE APPARENT. ONE WILL BE DOWNSTREAM OF AN ONGOING
CLUSTER ACROSS WRN TN. THE OTHERS SHOULD BE ALONG A QUASI-STATIONARY
FRONT BISECTING NY INTO SRN NEW ENGLAND AND PERHAPS IN ASSOCIATION
WITH A WEAK MCV MOVING INTO LOWER MI. MULTICELL CLUSTERS AND A FEW
SUPERCELLS WILL BE PRIMARILY CAPABLE OF ISOLATED DAMAGING WINDS AND
SEVERE HAIL.
000
ACUS01 KWNS 211959
SWODY1
SPC AC 211958
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT TUE MAY 21 2013
VALID 212000Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER NORTH CENTRAL AND NERN
TX...SERN OK...SRN AR...AND NRN LA...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN PLAINS ACROSS THE
TN VALLEY...LOWER GREAT LAKES...AND THE NERN STATES...
...SRN PLAINS INTO THE TN VALLEY...
A SERIES OF LINEAR CONVECTIVE SYSTEMS ARE MOVING EWD FROM SERN
OK/NORTH CENTRAL TX INTO AR AND KY/TN...IN ADVANCE OF AN UPPER
VORTICITY MAX/SHORT WAVE TROUGH LOCATED OVER THE TX PANHANDLE.
STRONG DIABATIC HEATING HAS OCCURRED SOUTH OF A CONVECTIVE BOUNDARY
ARCING FROM EAST CENTRAL AR ACROSS SRN AR INTO NORTH CENTRAL
TX...AND WITH STEEP LAPSE RATES /REF 18Z FWD AND 19Z SHV SPECIAL
RAOBS/ IN PLACE COUPLED WITH SURFACE DEW POINTS AROUND 70F...THE
ENVIRONMENT HAS BECOME VERY UNSTABLE WITH SBCAPE NEAR 3500 J/KG.
VISIBLE IMAGERY SHOWS CLOUD STREETS OVER ERN TX AND LA FEEDING NWD
TOWARD THE THERMAL BOUNDARY INDICATING A FAVORABLE MOISTURE
TRANSPORT INTO THE AREA. LOW-LEVEL CONVERGENCE IS FOCUSED IN THREE
AREAS: 1) NEAR A SURFACE LOW OVER THE METROPLEX...2) ALONG THE COLD
FRONT EXTENDING SWWD INTO THE HILL COUNTRY...AND 3) ALONG THE
EAST/WEST CONVECTIVE BOUNDARY ACROSS NERN TX/SWRN AR. STORMS ARE
EXPECTED TO INTENSIFY THE REMAINDER OF THIS AFTERNOON INTO THE
EVENING AS THE UPPER SYSTEM AND SURFACE LOW MOVE EWD...WITH
POTENTIAL FOR SUPERCELLS AND BOWING LINE SEGMENTS. 12Z NSSL WRF-ARW
AND RECENT HRRR MODELS INDICATE DEVELOPMENT OF LONG-LIVED BOWING
QLCS/S MOVING EWD ACROSS NERN TX INTO SRN AR AND NRN LA...AND
ENVIRONMENT APPEARS SUPPORTIVE OF THIS EVENT. THUS...WILL MAINTAIN
POTENTIAL FOR VERY LARGE HAIL AND SEVERAL TORNADOES /INCLUDING ONE
OR TWO STRONG TORNADOES/ ASSOCIATED PRIMARILY WITH ANY SUPERCELLS
THAT FORM...ALONG WITH WIDESPREAD SIGNIFICANT WIND DAMAGE GIVEN THE
POTENTIAL FOR A PROGRESSIVE BOWING CONVECTIVE SYSTEM TO FORM WITHIN
THE NEXT 1-2 HRS.
ELSEWHERE FROM THE MID-SOUTH INTO THE TN VALLEY...ADDITIONAL LINEAR
CONVECTIVE SYSTEMS OVER ERN AR AND SRN KY/MIDDLE TN ARE LIKELY TO
PROGRESS EWD/NEWD OVER THE NEXT SEVERAL HOURS...WHILE NEW
STRONG/SEVERE STORMS HAVE DEVELOPED ALONG THE TRAILING OUTFLOW
BOUNDARY OVER FAR NRN MS. GIVEN THE DEGREE OF INSTABILITY WITH CAPE
OF 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40 KT...A THREAT FOR
DAMAGING WINDS AND HAIL WILL CONTINUE WITH THESE STORMS.
..WEISS.. 05/21/2013
.PREV DISCUSSION... /ISSUED 1128 AM CDT TUE MAY 21 2013/
...SUBSTANTIAL SEVERE WEATHER EXPECTED ACROSS N-CNTRL TX TO THE
ARKLATEX THIS AFTERNOON AND EVENING...
..SRN PLAINS TO LOWER MS VALLEY...
SIGNIFICANT SEVERE WEATHER EPISODE INITIALLY UNFOLDING ACROSS THE
RED RIVER WITH SUPERCELLS PRODUCING LARGE HAIL ALONG AND N OF THE
COMPOSITE OUTFLOW/COLD FRONT PUSHING SWD FROM THE BIG COUNTRY TO FAR
SERN OK AHEAD OF A WELL-DEFINED SHORTWAVE TROUGH OVER THE SRN HIGH
PLAINS. AIR MASS S OF THE BOUNDARY IS BECOMING STRONGLY UNSTABLE AS
GRADUAL SURFACE HEATING CONTINUES AMIDST LOWEST 100 MB MEAN MIXING
RATIOS OF 14-17 G/KG AND 700-500 MB LAPSE RATES OF 8 TO 9.5 DEG C/KM
SAMPLED IN ALL REGIONAL 12Z RAOBS. AS MLCIN IS MINIMIZED ALONG THE
DRYLINE MIXING EWD ACROSS THE EDWARDS PLATEAU...ADDITIONAL SUPERCELL
DEVELOPMENT IS ANTICIPATED WITH SWD EXTENT.
A BELT OF 50-60 KT MID-LEVEL SWLYS ATTENDANT TO THE COMPACT
SHORTWAVE TROUGH WILL PROMOTE RISKS FOR ALL SEVERE TYPES /SOME OF
WHICH WILL BE SIGNIFICANT/. MORNING CONVECTION-ALLOWING WRF AND HRRR
SIMULATIONS ARE INSISTENT THAT UPSCALE GROWTH WILL OCCUR THROUGHOUT
THE AFTERNOON. GIVEN THE DEGREE OF INSTABILITY...BUOYANCY AND
SHEAR...SETUP MAY YIELD A DERECHO ACCELERATING EWD TOWARDS THE
ARKLATEX REGION BY EARLY EVENING. HERE TOO...THE STRONGEST LOW-LEVEL
S/SWLYS WILL REMAIN...PROMOTING EMBEDDED MESOVORTICES CAPABLE OF
PRODUCING A COUPLE OF SIGNIFICANT TORNADOES. OTHERWISE...POTENTIAL
DOES EXIST FOR WIDESPREAD/DESTRUCTIVE DAMAGING WIND GUSTS.
...TN VALLEY TO THE LOWER GREAT LAKES/NORTHEAST...
A BROAD AREA OF ORGANIZED SEVERE POTENTIAL IS EXPECTED ALONG THE ERN
EXTENT OF THE ELEVATED MIXED LAYER PLUME SAMPLED IN 12Z RAOBS. WITH
ROBUST HEATING...MODERATE TO STRONG INSTABILITY IS ANTICIPATED...BUT
MOST OF THE REGION WILL REMAIN ON THE FRINGE OF SUFFICIENT
DEEP-LAYER SHEAR FOR SUPERCELLS. THREE ZONES OF FOCUS FOR SUSTAINED
CONVECTION ARE APPARENT. ONE WILL BE DOWNSTREAM OF AN ONGOING
CLUSTER ACROSS WRN TN. THE OTHERS SHOULD BE ALONG A QUASI-STATIONARY
FRONT BISECTING NY INTO SRN NEW ENGLAND AND PERHAPS IN ASSOCIATION
WITH A WEAK MCV MOVING INTO LOWER MI. MULTICELL CLUSTERS AND A FEW
SUPERCELLS WILL BE PRIMARILY CAPABLE OF ISOLATED DAMAGING WINDS AND
SEVERE HAIL.
000
ACUS11 KWNS 211943
SWOMCD
SPC MCD 211942
ALZ000-TNZ000-MSZ000-KYZ000-MOZ000-ARZ000-212045-
MESOSCALE DISCUSSION 0755
NWS STORM PREDICTION CENTER NORMAN OK
0242 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN AR...WRN TN...NRN MS...MO BOOTHEEL.
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211942Z - 212045Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTMS HAVE RAPIDLY INCREASED IN INTENSITY ACROSS ERN AR
AND NRN MS. THE ENVIRONMENT IS BECOMING INCREASINGLY FAVORABLE FOR
DMGG WINDS...LARGE HAIL...AND PERHAPS A FEW TORNADOES. A WW WILL
LIKELY BE COORDINATED SOON WITH LOCAL FORECAST OFFICES.
DISCUSSION...NRN SEGMENT OF MCS MOVING ACROSS AR HAS FRAGMENTED
ACROSS CNTRL AR...AND IS PROGRESSING NEARLY DUE EWD ACROSS ERN AR.
ADDITIONAL MORE DISCRETE STORMS HAVE DEVELOPED ACROSS NRN MS. VWP
DATA FROM NQA SHOWS FAVORABLY BACKED SFC WINDS WITH VEERING IN THE
0-1 KM LAYER...RESULTING IN 0-1 SRH NEAR 150 M^2 S^-2.
ADDITIONALLY...BREAKS IN CLOUDINESS HAVE RESULTED IN TEMPERATURES
HEATING UP INTO THE UPPER 70S TO LOWER 80S F...RESULTING IN AN
INCREASINGLY UNSTABLE ENVIRONMENT. THIS WILL BE FAVORABLE FOR LARGE
HAIL AND DMGG WINDS...AS WELL AS TORNADOES ESPECIALLY WITH DISCRETE
STORMS. A WW WILL BE COORDINATED SOON.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...JAN...LZK...
LAT...LON 34618819 34248842 33898919 33908975 34119067 34319105
35039136 35659128 36099119 36379068 36689007 36438903
36278799 34618819
000
ACUS11 KWNS 211943
SWOMCD
SPC MCD 211942
ALZ000-TNZ000-MSZ000-KYZ000-MOZ000-ARZ000-212045-
MESOSCALE DISCUSSION 0755
NWS STORM PREDICTION CENTER NORMAN OK
0242 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN AR...WRN TN...NRN MS...MO BOOTHEEL.
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211942Z - 212045Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTMS HAVE RAPIDLY INCREASED IN INTENSITY ACROSS ERN AR
AND NRN MS. THE ENVIRONMENT IS BECOMING INCREASINGLY FAVORABLE FOR
DMGG WINDS...LARGE HAIL...AND PERHAPS A FEW TORNADOES. A WW WILL
LIKELY BE COORDINATED SOON WITH LOCAL FORECAST OFFICES.
DISCUSSION...NRN SEGMENT OF MCS MOVING ACROSS AR HAS FRAGMENTED
ACROSS CNTRL AR...AND IS PROGRESSING NEARLY DUE EWD ACROSS ERN AR.
ADDITIONAL MORE DISCRETE STORMS HAVE DEVELOPED ACROSS NRN MS. VWP
DATA FROM NQA SHOWS FAVORABLY BACKED SFC WINDS WITH VEERING IN THE
0-1 KM LAYER...RESULTING IN 0-1 SRH NEAR 150 M^2 S^-2.
ADDITIONALLY...BREAKS IN CLOUDINESS HAVE RESULTED IN TEMPERATURES
HEATING UP INTO THE UPPER 70S TO LOWER 80S F...RESULTING IN AN
INCREASINGLY UNSTABLE ENVIRONMENT. THIS WILL BE FAVORABLE FOR LARGE
HAIL AND DMGG WINDS...AS WELL AS TORNADOES ESPECIALLY WITH DISCRETE
STORMS. A WW WILL BE COORDINATED SOON.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...JAN...LZK...
LAT...LON 34618819 34248842 33898919 33908975 34119067 34319105
35039136 35659128 36099119 36379068 36689007 36438903
36278799 34618819
000
ACUS11 KWNS 211943
SWOMCD
SPC MCD 211942
ALZ000-TNZ000-MSZ000-KYZ000-MOZ000-ARZ000-212045-
MESOSCALE DISCUSSION 0755
NWS STORM PREDICTION CENTER NORMAN OK
0242 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ERN AR...WRN TN...NRN MS...MO BOOTHEEL.
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211942Z - 212045Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...TSTMS HAVE RAPIDLY INCREASED IN INTENSITY ACROSS ERN AR
AND NRN MS. THE ENVIRONMENT IS BECOMING INCREASINGLY FAVORABLE FOR
DMGG WINDS...LARGE HAIL...AND PERHAPS A FEW TORNADOES. A WW WILL
LIKELY BE COORDINATED SOON WITH LOCAL FORECAST OFFICES.
DISCUSSION...NRN SEGMENT OF MCS MOVING ACROSS AR HAS FRAGMENTED
ACROSS CNTRL AR...AND IS PROGRESSING NEARLY DUE EWD ACROSS ERN AR.
ADDITIONAL MORE DISCRETE STORMS HAVE DEVELOPED ACROSS NRN MS. VWP
DATA FROM NQA SHOWS FAVORABLY BACKED SFC WINDS WITH VEERING IN THE
0-1 KM LAYER...RESULTING IN 0-1 SRH NEAR 150 M^2 S^-2.
ADDITIONALLY...BREAKS IN CLOUDINESS HAVE RESULTED IN TEMPERATURES
HEATING UP INTO THE UPPER 70S TO LOWER 80S F...RESULTING IN AN
INCREASINGLY UNSTABLE ENVIRONMENT. THIS WILL BE FAVORABLE FOR LARGE
HAIL AND DMGG WINDS...AS WELL AS TORNADOES ESPECIALLY WITH DISCRETE
STORMS. A WW WILL BE COORDINATED SOON.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...JAN...LZK...
LAT...LON 34618819 34248842 33898919 33908975 34119067 34319105
35039136 35659128 36099119 36379068 36689007 36438903
36278799 34618819
000
ACUS11 KWNS 211913
SWOMCD
SPC MCD 211912
KYZ000-VAZ000-TNZ000-212015-
MESOSCALE DISCUSSION 0754
NWS STORM PREDICTION CENTER NORMAN OK
0212 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL/ERN KY...MIDDLE/ERN TN
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211912Z - 212015Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...QLCS MOVING ACROSS MIDDLE TN AND CNTRL KY HAS SHOWN RECENT
SIGNS OF ORGANIZING/INTENSIFYING. A DMGG WIND AND PERHAPS A
MARGINALLY SVR HAIL THREAT MAY ACCOMPANY THIS LINE AS IT CONTINUES
PROGRESSING EWD. A WW WILL LIKELY BE NEEDED.
DISCUSSION...RADAR TRENDS CONTINUE TO SHOW AN INCREASINGLY ORGANIZED
QLCS DEVELOPING ACROSS MIDDLE TN INTO CNTRL KY...WITH SEVERAL SVR
GUSTS NOTED AROUND THE NASHVILLE AREA RECENTLY. ADDITIONAL
INTENSIFICATION HAS OCCURRED FARTHER N INTO PORTIONS OF KY. STRONG
HEATING DOWNSTREAM FROM THIS LINE WITHIN A MOIST BOUNDARY LAYER IS
YIELDING MLCAPE VALUES OF 2000-3000 J/KG. THUS...A DMGG WIND THREAT
MAY CONTINUE E INTO ADDITIONAL PARTS OF CNTRL/ERN KY AND MIDDLE/ERN
TN...LIKELY REQUIRING A WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...
LAT...LON 37348303 36248338 35718389 35548440 35458530 35758559
36958554 37918559 38148453 38158365 37948312 37348303
000
ACUS11 KWNS 211913
SWOMCD
SPC MCD 211912
KYZ000-VAZ000-TNZ000-212015-
MESOSCALE DISCUSSION 0754
NWS STORM PREDICTION CENTER NORMAN OK
0212 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL/ERN KY...MIDDLE/ERN TN
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211912Z - 212015Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...QLCS MOVING ACROSS MIDDLE TN AND CNTRL KY HAS SHOWN RECENT
SIGNS OF ORGANIZING/INTENSIFYING. A DMGG WIND AND PERHAPS A
MARGINALLY SVR HAIL THREAT MAY ACCOMPANY THIS LINE AS IT CONTINUES
PROGRESSING EWD. A WW WILL LIKELY BE NEEDED.
DISCUSSION...RADAR TRENDS CONTINUE TO SHOW AN INCREASINGLY ORGANIZED
QLCS DEVELOPING ACROSS MIDDLE TN INTO CNTRL KY...WITH SEVERAL SVR
GUSTS NOTED AROUND THE NASHVILLE AREA RECENTLY. ADDITIONAL
INTENSIFICATION HAS OCCURRED FARTHER N INTO PORTIONS OF KY. STRONG
HEATING DOWNSTREAM FROM THIS LINE WITHIN A MOIST BOUNDARY LAYER IS
YIELDING MLCAPE VALUES OF 2000-3000 J/KG. THUS...A DMGG WIND THREAT
MAY CONTINUE E INTO ADDITIONAL PARTS OF CNTRL/ERN KY AND MIDDLE/ERN
TN...LIKELY REQUIRING A WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...
LAT...LON 37348303 36248338 35718389 35548440 35458530 35758559
36958554 37918559 38148453 38158365 37948312 37348303
000
ACUS11 KWNS 211913
SWOMCD
SPC MCD 211912
KYZ000-VAZ000-TNZ000-212015-
MESOSCALE DISCUSSION 0754
NWS STORM PREDICTION CENTER NORMAN OK
0212 PM CDT TUE MAY 21 2013
AREAS AFFECTED...CNTRL/ERN KY...MIDDLE/ERN TN
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211912Z - 212015Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...QLCS MOVING ACROSS MIDDLE TN AND CNTRL KY HAS SHOWN RECENT
SIGNS OF ORGANIZING/INTENSIFYING. A DMGG WIND AND PERHAPS A
MARGINALLY SVR HAIL THREAT MAY ACCOMPANY THIS LINE AS IT CONTINUES
PROGRESSING EWD. A WW WILL LIKELY BE NEEDED.
DISCUSSION...RADAR TRENDS CONTINUE TO SHOW AN INCREASINGLY ORGANIZED
QLCS DEVELOPING ACROSS MIDDLE TN INTO CNTRL KY...WITH SEVERAL SVR
GUSTS NOTED AROUND THE NASHVILLE AREA RECENTLY. ADDITIONAL
INTENSIFICATION HAS OCCURRED FARTHER N INTO PORTIONS OF KY. STRONG
HEATING DOWNSTREAM FROM THIS LINE WITHIN A MOIST BOUNDARY LAYER IS
YIELDING MLCAPE VALUES OF 2000-3000 J/KG. THUS...A DMGG WIND THREAT
MAY CONTINUE E INTO ADDITIONAL PARTS OF CNTRL/ERN KY AND MIDDLE/ERN
TN...LIKELY REQUIRING A WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...
LAT...LON 37348303 36248338 35718389 35548440 35458530 35758559
36958554 37918559 38148453 38158365 37948312 37348303
000
ACUS11 KWNS 211835
SWOMCD
SPC MCD 211835
ARZ000-LAZ000-TXZ000-212030-
MESOSCALE DISCUSSION 0753
NWS STORM PREDICTION CENTER NORMAN OK
0135 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ARKLATEX REGION
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211835Z - 212030Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...A CONDITIONAL THREAT FOR TORNADOES HAS ARISEN ACROSS THE
ARKLATEX REGION...AND A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...HEATING HAS ERODED CAPPING OVER NERN TX INTO SRN AR AND
NRN LA WHERE DEWPOINTS ARE IN THE 68-72 F RANGE...CREATING VERY
STRONG INSTABILITY. MEANWHILE...A FEW SMALL CELLS HAVE RECENTLY
FORMED JUST S OF A SWD ADVANCING OUTFLOW BOUNDARY NOW INTO FAR NERN
TX. ALTHOUGH THE AIR N OF THIS BOUNDARY IS RELATIVELY
STABLE...CONDITIONS ARE FAVORABLE FOR TORNADOES...PERHAPS EVEN
STRONG...S OF THE BOUNDARY.
A CONFLUENCE AXIS MAY BE SETTING UP ACROSS THE AREA...AND WITH
CONTINUED HEATING...THIS MAY BE ENOUGH FOR ISOLATED STORMS TO
FORM...WELL AHEAD OF THE ADVANCING COLD FRONT TO THE W.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...FWD...
LAT...LON 32319649 33239627 33599563 33569492 33539442 33569382
33299347 32529345 32239370 31959421 31819480 31849617
32319649
000
ACUS11 KWNS 211835
SWOMCD
SPC MCD 211835
ARZ000-LAZ000-TXZ000-212030-
MESOSCALE DISCUSSION 0753
NWS STORM PREDICTION CENTER NORMAN OK
0135 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ARKLATEX REGION
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211835Z - 212030Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...A CONDITIONAL THREAT FOR TORNADOES HAS ARISEN ACROSS THE
ARKLATEX REGION...AND A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...HEATING HAS ERODED CAPPING OVER NERN TX INTO SRN AR AND
NRN LA WHERE DEWPOINTS ARE IN THE 68-72 F RANGE...CREATING VERY
STRONG INSTABILITY. MEANWHILE...A FEW SMALL CELLS HAVE RECENTLY
FORMED JUST S OF A SWD ADVANCING OUTFLOW BOUNDARY NOW INTO FAR NERN
TX. ALTHOUGH THE AIR N OF THIS BOUNDARY IS RELATIVELY
STABLE...CONDITIONS ARE FAVORABLE FOR TORNADOES...PERHAPS EVEN
STRONG...S OF THE BOUNDARY.
A CONFLUENCE AXIS MAY BE SETTING UP ACROSS THE AREA...AND WITH
CONTINUED HEATING...THIS MAY BE ENOUGH FOR ISOLATED STORMS TO
FORM...WELL AHEAD OF THE ADVANCING COLD FRONT TO THE W.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...FWD...
LAT...LON 32319649 33239627 33599563 33569492 33539442 33569382
33299347 32529345 32239370 31959421 31819480 31849617
32319649
000
ACUS11 KWNS 211835
SWOMCD
SPC MCD 211835
ARZ000-LAZ000-TXZ000-212030-
MESOSCALE DISCUSSION 0753
NWS STORM PREDICTION CENTER NORMAN OK
0135 PM CDT TUE MAY 21 2013
AREAS AFFECTED...ARKLATEX REGION
CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY
VALID 211835Z - 212030Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...A CONDITIONAL THREAT FOR TORNADOES HAS ARISEN ACROSS THE
ARKLATEX REGION...AND A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...HEATING HAS ERODED CAPPING OVER NERN TX INTO SRN AR AND
NRN LA WHERE DEWPOINTS ARE IN THE 68-72 F RANGE...CREATING VERY
STRONG INSTABILITY. MEANWHILE...A FEW SMALL CELLS HAVE RECENTLY
FORMED JUST S OF A SWD ADVANCING OUTFLOW BOUNDARY NOW INTO FAR NERN
TX. ALTHOUGH THE AIR N OF THIS BOUNDARY IS RELATIVELY
STABLE...CONDITIONS ARE FAVORABLE FOR TORNADOES...PERHAPS EVEN
STRONG...S OF THE BOUNDARY.
A CONFLUENCE AXIS MAY BE SETTING UP ACROSS THE AREA...AND WITH
CONTINUED HEATING...THIS MAY BE ENOUGH FOR ISOLATED STORMS TO
FORM...WELL AHEAD OF THE ADVANCING COLD FRONT TO THE W.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...FWD...
LAT...LON 32319649 33239627 33599563 33569492 33539442 33569382
33299347 32529345 32239370 31959421 31819480 31849617
32319649
000
ACUS11 KWNS 211819
SWOMCD
SPC MCD 211819
TXZ000-OKZ000-212015-
MESOSCALE DISCUSSION 0752
NWS STORM PREDICTION CENTER NORMAN OK
0119 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NRN TX INTO THE ARKLATEX REGION
CONCERNING...TORNADO WATCH 201...
VALID 211819Z - 212015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201 CONTINUES.
SUMMARY...STORMS ARE GRADUALLY INCREASING IN COVERAGE...AND MAY
RAPIDLY INTENSIFY CLOSE TO OR JUST E OF THE DALLAS/FT. WORTH AREA
EWD INTO THE ARKLATEX WITH MAINLY DAMAGING WINDS AND HAIL.
DISCUSSION...SURFACE ANALYSIS AND VISIBLE IMAGERY SHOW THAT A BAND
OF THICK STRATUS CONTINUES TO HAMPER HEATING AND SURFACE BASED
DESTABILIZATION W OF THE I-35 CORRIDOR IN TX AS OUTFLOW AND COLD
FRONT CONTINUE TO RAPIDLY TRAVEL SEWD OVER WRN N TX.
CURRENTLY...THESE STORMS ARE FORMING MAINLY BEHIND THE LEADING
OUTFLOW...DUE IN PART TO THE COOLER SURFACE AIR AND MARGINAL STORM
RELATIVE INFLOW.
HOWEVER...HEATING PERSISTS ALONG AND E OF I-35...WITH TEMPERATURES
MAINLY IN THE 82-84 F RANGE. MODIFICATION OF THE 18Z FWD SOUNDING
SUGGESTS CAPPING IN THESE AREAS IS AT A MINIMUM...AND THAT THE
APPROACHING LINE OF CONVECTION WILL STRENGTHEN AS IT BEGINS TO
INGEST MORE UNSTABLE AIR. A GENERAL SWWD GROWTH ALONG THE COLD FRONT
IS ALSO EXPECTED LATER THIS AFTERNOON TOWARD THE WACO AREA. GIVEN
THE RAPIDLY ADVANCING GUST FRONT...AND VEERED 850 MB WINDS PRIMARILY
PARALLEL TO THE BOUNDARY...THE TORNADO THREAT MAY NOT BE HIGH...BUT
IF SUPERCELLS CAN FORM THEN ROTATION COULD DEVELOP ALONG ANY
INFLECTION POINTS IN THE LINE.
ELSEWHERE...AN OUTFLOW BOUNDARY CONTINUES TO SAG SWD ACROSS THE RED
RIVER INTO NRN TX AND SWRN AR...WITH SPORADIC SMALL STORMS FORMING
TO THE N OF IT. THESE CELLS MAY BECOME A BIT BETTER ORGANIZED AS THE
UPPER TROUGH NEARS...AND SOME FURTHER DESTABILIZATION OCCURS
UPSTREAM. DEEP LAYER SHEAR WILL REMAIN FAVORABLE FOR ELEVATED SEVERE
HAIL WITH THIS ACTIVITY PRIOR TO THE MAIN LINE OF STORMS ARRIVING
ACROSS THE RED RIVER VALLEY AND SWRN AR. ALSO...THERE IS A
CONDITIONAL TORNADO THREAT IF CELLS CAN MATURE BEFORE THEY CROSS THE
OUTFLOW BOUNDARY. HOWEVER...CELL MOTION WOULD CAUSE THESE STORMS TO
LOSE TORNADO THREAT QUICKLY ONCE THEY CROSS THE FRONT.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT...
LAT...LON 31809521 30370000 31639999 31789932 32529810 33249758
34009713 34539520 31809521
000
ACUS11 KWNS 211819
SWOMCD
SPC MCD 211819
TXZ000-OKZ000-212015-
MESOSCALE DISCUSSION 0752
NWS STORM PREDICTION CENTER NORMAN OK
0119 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NRN TX INTO THE ARKLATEX REGION
CONCERNING...TORNADO WATCH 201...
VALID 211819Z - 212015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201 CONTINUES.
SUMMARY...STORMS ARE GRADUALLY INCREASING IN COVERAGE...AND MAY
RAPIDLY INTENSIFY CLOSE TO OR JUST E OF THE DALLAS/FT. WORTH AREA
EWD INTO THE ARKLATEX WITH MAINLY DAMAGING WINDS AND HAIL.
DISCUSSION...SURFACE ANALYSIS AND VISIBLE IMAGERY SHOW THAT A BAND
OF THICK STRATUS CONTINUES TO HAMPER HEATING AND SURFACE BASED
DESTABILIZATION W OF THE I-35 CORRIDOR IN TX AS OUTFLOW AND COLD
FRONT CONTINUE TO RAPIDLY TRAVEL SEWD OVER WRN N TX.
CURRENTLY...THESE STORMS ARE FORMING MAINLY BEHIND THE LEADING
OUTFLOW...DUE IN PART TO THE COOLER SURFACE AIR AND MARGINAL STORM
RELATIVE INFLOW.
HOWEVER...HEATING PERSISTS ALONG AND E OF I-35...WITH TEMPERATURES
MAINLY IN THE 82-84 F RANGE. MODIFICATION OF THE 18Z FWD SOUNDING
SUGGESTS CAPPING IN THESE AREAS IS AT A MINIMUM...AND THAT THE
APPROACHING LINE OF CONVECTION WILL STRENGTHEN AS IT BEGINS TO
INGEST MORE UNSTABLE AIR. A GENERAL SWWD GROWTH ALONG THE COLD FRONT
IS ALSO EXPECTED LATER THIS AFTERNOON TOWARD THE WACO AREA. GIVEN
THE RAPIDLY ADVANCING GUST FRONT...AND VEERED 850 MB WINDS PRIMARILY
PARALLEL TO THE BOUNDARY...THE TORNADO THREAT MAY NOT BE HIGH...BUT
IF SUPERCELLS CAN FORM THEN ROTATION COULD DEVELOP ALONG ANY
INFLECTION POINTS IN THE LINE.
ELSEWHERE...AN OUTFLOW BOUNDARY CONTINUES TO SAG SWD ACROSS THE RED
RIVER INTO NRN TX AND SWRN AR...WITH SPORADIC SMALL STORMS FORMING
TO THE N OF IT. THESE CELLS MAY BECOME A BIT BETTER ORGANIZED AS THE
UPPER TROUGH NEARS...AND SOME FURTHER DESTABILIZATION OCCURS
UPSTREAM. DEEP LAYER SHEAR WILL REMAIN FAVORABLE FOR ELEVATED SEVERE
HAIL WITH THIS ACTIVITY PRIOR TO THE MAIN LINE OF STORMS ARRIVING
ACROSS THE RED RIVER VALLEY AND SWRN AR. ALSO...THERE IS A
CONDITIONAL TORNADO THREAT IF CELLS CAN MATURE BEFORE THEY CROSS THE
OUTFLOW BOUNDARY. HOWEVER...CELL MOTION WOULD CAUSE THESE STORMS TO
LOSE TORNADO THREAT QUICKLY ONCE THEY CROSS THE FRONT.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT...
LAT...LON 31809521 30370000 31639999 31789932 32529810 33249758
34009713 34539520 31809521
000
ACUS11 KWNS 211819
SWOMCD
SPC MCD 211819
TXZ000-OKZ000-212015-
MESOSCALE DISCUSSION 0752
NWS STORM PREDICTION CENTER NORMAN OK
0119 PM CDT TUE MAY 21 2013
AREAS AFFECTED...NRN TX INTO THE ARKLATEX REGION
CONCERNING...TORNADO WATCH 201...
VALID 211819Z - 212015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201 CONTINUES.
SUMMARY...STORMS ARE GRADUALLY INCREASING IN COVERAGE...AND MAY
RAPIDLY INTENSIFY CLOSE TO OR JUST E OF THE DALLAS/FT. WORTH AREA
EWD INTO THE ARKLATEX WITH MAINLY DAMAGING WINDS AND HAIL.
DISCUSSION...SURFACE ANALYSIS AND VISIBLE IMAGERY SHOW THAT A BAND
OF THICK STRATUS CONTINUES TO HAMPER HEATING AND SURFACE BASED
DESTABILIZATION W OF THE I-35 CORRIDOR IN TX AS OUTFLOW AND COLD
FRONT CONTINUE TO RAPIDLY TRAVEL SEWD OVER WRN N TX.
CURRENTLY...THESE STORMS ARE FORMING MAINLY BEHIND THE LEADING
OUTFLOW...DUE IN PART TO THE COOLER SURFACE AIR AND MARGINAL STORM
RELATIVE INFLOW.
HOWEVER...HEATING PERSISTS ALONG AND E OF I-35...WITH TEMPERATURES
MAINLY IN THE 82-84 F RANGE. MODIFICATION OF THE 18Z FWD SOUNDING
SUGGESTS CAPPING IN THESE AREAS IS AT A MINIMUM...AND THAT THE
APPROACHING LINE OF CONVECTION WILL STRENGTHEN AS IT BEGINS TO
INGEST MORE UNSTABLE AIR. A GENERAL SWWD GROWTH ALONG THE COLD FRONT
IS ALSO EXPECTED LATER THIS AFTERNOON TOWARD THE WACO AREA. GIVEN
THE RAPIDLY ADVANCING GUST FRONT...AND VEERED 850 MB WINDS PRIMARILY
PARALLEL TO THE BOUNDARY...THE TORNADO THREAT MAY NOT BE HIGH...BUT
IF SUPERCELLS CAN FORM THEN ROTATION COULD DEVELOP ALONG ANY
INFLECTION POINTS IN THE LINE.
ELSEWHERE...AN OUTFLOW BOUNDARY CONTINUES TO SAG SWD ACROSS THE RED
RIVER INTO NRN TX AND SWRN AR...WITH SPORADIC SMALL STORMS FORMING
TO THE N OF IT. THESE CELLS MAY BECOME A BIT BETTER ORGANIZED AS THE
UPPER TROUGH NEARS...AND SOME FURTHER DESTABILIZATION OCCURS
UPSTREAM. DEEP LAYER SHEAR WILL REMAIN FAVORABLE FOR ELEVATED SEVERE
HAIL WITH THIS ACTIVITY PRIOR TO THE MAIN LINE OF STORMS ARRIVING
ACROSS THE RED RIVER VALLEY AND SWRN AR. ALSO...THERE IS A
CONDITIONAL TORNADO THREAT IF CELLS CAN MATURE BEFORE THEY CROSS THE
OUTFLOW BOUNDARY. HOWEVER...CELL MOTION WOULD CAUSE THESE STORMS TO
LOSE TORNADO THREAT QUICKLY ONCE THEY CROSS THE FRONT.
..JEWELL.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT...
LAT...LON 31809521 30370000 31639999 31789932 32529810 33249758
34009713 34539520 31809521
000
ACUS02 KWNS 211706
SWODY2
SPC AC 211705
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1205 PM CDT TUE MAY 21 2013
VALID 221200Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER GREAT LAKES INTO
THE OH/TN VALLEYS...
...SYNOPSIS...
HIGH AMPLITUDE BLOCKING PATTERN IS FORECAST TO CONTINUE ON WEDNESDAY
AS AN UPPER LOW CURRENTLY OVER THE UPPER MIDWEST MOVES SLOWLY EWD
AND BEGINS TO PHASE WITH A NRN STREAM SHORT WAVE TROUGH MOVING SEWD
FROM THE HUDSON BAY REGION. IN THE WEST...A COLD UPPER LOW JUST OFF
THE PACIFIC NW COAST IS EXPECTED TO MOVE SLOWLY ONSHORE...AS A
DOWNSTREAM RIDGE DEVELOPS OVER THE SRN HIGH PLAINS.
AT THE SURFACE...A LOW INITIALLY OVER SRN LAKE MI IS FORECAST TO
DEVELOP EWD ACROSS SRN LOWER MI DURING THE AFTERNOON BEFORE LIFTING
NEWD TOWARD SWRN QUE BY THE END OF THE PERIOD. A COLD FRONT
EXTENDING SWWD FROM THIS LOW IS FORECAST TO MOVE SLOWLY SEWD ACROSS
THE MIDDLE OH VALLEY AND MID-SOUTH. THE WRN PART OF THE FRONT WILL
CURVE WWD/NWWD ACROSS OK AND INTO CO.
...LOWER GREAT LAKES INTO THE OH/TN VALLEYS...
STRONG/SEVERE THUNDERSTORMS DURING THE DAY 1 OVERNIGHT PERIOD ARE
EXPECTED TO BE WEAKENING OVER PARTS OF THE OH/TN VALLEYS BY 22/12Z.
LINGERING CLOUDS AND SCATTERED AREAS OF PRECIPITATION ARE LIKELY TO
INHIBIT WIDESPREAD DIABATIC HEATING AND SUBSEQUENT STRONG
DESTABILIZATION INTO THE AFTERNOON. HOWEVER...BREAKS IN CLOUD COVER
ARE EXPECTED TO BE PRESENT AND WILL FOSTER LOCALIZED REGIONS OF
STRONGER HEATING. WITH AMPLE LOW LEVEL MOISTURE IN PLACE /SURFACE
DEW POINTS IN THE 65-70F RANGE/ POCKETS OF STRONGER INSTABILITY WITH
SBCAPE OF 1000-1500 J/KG ARE EXPECTED TO DEVELOP.
SEVERAL BANDS OF THUNDERSTORMS ARE EXPECTED TO INCREASE DURING THE
AFTERNOON...POSSIBLY AIDED BY REMNANT OUTFLOW BOUNDARIES FROM
OVERNIGHT/MORNING CONVECTION AHEAD OF THE COLD FRONT. KINEMATIC
GUIDANCE FROM NWP MODELS IS CONSISTENT SHOWING STRENGTHENING SSWLY
WINDS ALOFT ABOVE THE GROUND SPREADING ACROSS THE OH VALLEY AND
LOWER GREAT LAKES DURING THE AFTERNOON...WITH UNIDIRECTIONAL 40-50
KT FLOW ABOVE 1-2 KM. THIS WIND PROFILE WILL ENHANCE STORM
ORGANIZATION WITH POTENTIAL FOR A FEW BOWING LINE SEGMENTS AND
POSSIBLY SMALL SUPERCELLS TO DEVELOP...ESPECIALLY OVER PARTS OF OH
AND EXTREME SERN LOWER MI WHERE HIGHER SEVERE PROBABILITY VALUES
HAVE BEEN INTRODUCED. DAMAGING WIND GUSTS...MARGINALLY SEVERE
HAIL...AND POSSIBLY A TORNADO OR TWO WILL BE POSSIBLE WITH STRONGER
STORMS INTO THE EVENING HOURS.
OTHER STORMS ARE LIKELY TO DEVELOP FARTHER EAST OVER PARTS OF NY/PA
WHERE STRONGER DIURNAL HEATING IS EXPECTED WITHIN A WEAKLY CAPPED
UNSTABLE ENVIRONMENT. ALTHOUGH VERTICAL WIND SHEAR WILL BE WEAKER
IN THIS AREA...A FEW MULTICELLULAR STORM CLUSTERS ARE EXPECTED TO
DEVELOP WITH POTENTIAL TO PRODUCE DAMAGING WIND GUSTS AND HAIL.
...LOWER MS VALLEY INTO SERN TX...
OVERNIGHT CONVECTION IS EXPECTED TO BE CONTINUING FROM WRN AL/MS
INTO SERN TX DURING THE MORNING...WITH ASSOCIATED CLOUD COVER LIKELY
INHIBITING STRONGER DESTABILIZATION IMMEDIATELY AHEAD OF THE STORMS.
ACTIVITY IS LIKELY TO SLOWLY SPREAD EWD/SEWD DURING THE DAY WITH
POTENTIAL FOR ISOLATED SEVERE STORMS PRODUCING WET MICROBURSTS OR
MARGINAL HAIL. WEAKENING FLOW ALOFT/VERTICAL SHEAR IS EXPECTED TO
LIMIT THE OVERALL SEVERE THREAT.
..WEISS.. 05/21/2013
000
ACUS02 KWNS 211706
SWODY2
SPC AC 211705
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1205 PM CDT TUE MAY 21 2013
VALID 221200Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LOWER GREAT LAKES INTO
THE OH/TN VALLEYS...
...SYNOPSIS...
HIGH AMPLITUDE BLOCKING PATTERN IS FORECAST TO CONTINUE ON WEDNESDAY
AS AN UPPER LOW CURRENTLY OVER THE UPPER MIDWEST MOVES SLOWLY EWD
AND BEGINS TO PHASE WITH A NRN STREAM SHORT WAVE TROUGH MOVING SEWD
FROM THE HUDSON BAY REGION. IN THE WEST...A COLD UPPER LOW JUST OFF
THE PACIFIC NW COAST IS EXPECTED TO MOVE SLOWLY ONSHORE...AS A
DOWNSTREAM RIDGE DEVELOPS OVER THE SRN HIGH PLAINS.
AT THE SURFACE...A LOW INITIALLY OVER SRN LAKE MI IS FORECAST TO
DEVELOP EWD ACROSS SRN LOWER MI DURING THE AFTERNOON BEFORE LIFTING
NEWD TOWARD SWRN QUE BY THE END OF THE PERIOD. A COLD FRONT
EXTENDING SWWD FROM THIS LOW IS FORECAST TO MOVE SLOWLY SEWD ACROSS
THE MIDDLE OH VALLEY AND MID-SOUTH. THE WRN PART OF THE FRONT WILL
CURVE WWD/NWWD ACROSS OK AND INTO CO.
...LOWER GREAT LAKES INTO THE OH/TN VALLEYS...
STRONG/SEVERE THUNDERSTORMS DURING THE DAY 1 OVERNIGHT PERIOD ARE
EXPECTED TO BE WEAKENING OVER PARTS OF THE OH/TN VALLEYS BY 22/12Z.
LINGERING CLOUDS AND SCATTERED AREAS OF PRECIPITATION ARE LIKELY TO
INHIBIT WIDESPREAD DIABATIC HEATING AND SUBSEQUENT STRONG
DESTABILIZATION INTO THE AFTERNOON. HOWEVER...BREAKS IN CLOUD COVER
ARE EXPECTED TO BE PRESENT AND WILL FOSTER LOCALIZED REGIONS OF
STRONGER HEATING. WITH AMPLE LOW LEVEL MOISTURE IN PLACE /SURFACE
DEW POINTS IN THE 65-70F RANGE/ POCKETS OF STRONGER INSTABILITY WITH
SBCAPE OF 1000-1500 J/KG ARE EXPECTED TO DEVELOP.
SEVERAL BANDS OF THUNDERSTORMS ARE EXPECTED TO INCREASE DURING THE
AFTERNOON...POSSIBLY AIDED BY REMNANT OUTFLOW BOUNDARIES FROM
OVERNIGHT/MORNING CONVECTION AHEAD OF THE COLD FRONT. KINEMATIC
GUIDANCE FROM NWP MODELS IS CONSISTENT SHOWING STRENGTHENING SSWLY
WINDS ALOFT ABOVE THE GROUND SPREADING ACROSS THE OH VALLEY AND
LOWER GREAT LAKES DURING THE AFTERNOON...WITH UNIDIRECTIONAL 40-50
KT FLOW ABOVE 1-2 KM. THIS WIND PROFILE WILL ENHANCE STORM
ORGANIZATION WITH POTENTIAL FOR A FEW BOWING LINE SEGMENTS AND
POSSIBLY SMALL SUPERCELLS TO DEVELOP...ESPECIALLY OVER PARTS OF OH
AND EXTREME SERN LOWER MI WHERE HIGHER SEVERE PROBABILITY VALUES
HAVE BEEN INTRODUCED. DAMAGING WIND GUSTS...MARGINALLY SEVERE
HAIL...AND POSSIBLY A TORNADO OR TWO WILL BE POSSIBLE WITH STRONGER
STORMS INTO THE EVENING HOURS.
OTHER STORMS ARE LIKELY TO DEVELOP FARTHER EAST OVER PARTS OF NY/PA
WHERE STRONGER DIURNAL HEATING IS EXPECTED WITHIN A WEAKLY CAPPED
UNSTABLE ENVIRONMENT. ALTHOUGH VERTICAL WIND SHEAR WILL BE WEAKER
IN THIS AREA...A FEW MULTICELLULAR STORM CLUSTERS ARE EXPECTED TO
DEVELOP WITH POTENTIAL TO PRODUCE DAMAGING WIND GUSTS AND HAIL.
...LOWER MS VALLEY INTO SERN TX...
OVERNIGHT CONVECTION IS EXPECTED TO BE CONTINUING FROM WRN AL/MS
INTO SERN TX DURING THE MORNING...WITH ASSOCIATED CLOUD COVER LIKELY
INHIBITING STRONGER DESTABILIZATION IMMEDIATELY AHEAD OF THE STORMS.
ACTIVITY IS LIKELY TO SLOWLY SPREAD EWD/SEWD DURING THE DAY WITH
POTENTIAL FOR ISOLATED SEVERE STORMS PRODUCING WET MICROBURSTS OR
MARGINAL HAIL. WEAKENING FLOW ALOFT/VERTICAL SHEAR IS EXPECTED TO
LIMIT THE OVERALL SEVERE THREAT.
..WEISS.. 05/21/2013
000
ACUS11 KWNS 211655
SWOMCD
SPC MCD 211654
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-211800-
MESOSCALE DISCUSSION 0751
NWS STORM PREDICTION CENTER NORMAN OK
1154 AM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN/CNTRL NY...SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211654Z - 211800Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...TSTMS SHOULD CONTINUE INCREASING IN INTENSITY...PRIMARILY
FOCUSED ALONG/S OF A QUASI-STATIONARY FRONT...ACROSS PORTIONS OF
WRN/CNTRL NY AND INTO SRN NEW ENGLAND THIS AFTERNOON. THE PRIMARY
THREATS WILL BE DMGG WIND GUSTS AND LARGE HAIL. A WW MAY BE NEEDED
IF CONVECTIVE TRENDS CONTINUE TO INCREASE.
DISCUSSION...SUBJECTIVE SFC ANALYSIS FROM 16Z PLACES A
QUASI-STATIONARY FRONT FROM NEAR ROC-ALB. A FEW STORMS HAVE RECENTLY
INITIATED ALONG THIS FRONT...LIKELY IN RESPONSE TO WEAK LOW-LEVEL
CONVERGENCE...WEAKENING CONVECTIVE INHIBITION...AND MODEST MIDLEVEL
MOISTENING/ASCENT AS NOTED ON WATER VAPOR. MODIFIED 12Z SOUNDINGS
FROM BOTH BUF AND ALB SUGGEST AMPLE INSTABILITY FOR THE DEVELOPMENT
OF STRONG-SVR TSTMS...WITH MLCAPE VALUES LIKELY EXCEEDING 2000
J/KG...GIVEN THE PRESENCE OF MODERATELY STEEP MIDLEVEL LAPSE RATES
AND RICH LOW-LEVEL MOISTURE. ADDITIONALLY...BOTH SOUNDING AND RECENT
VWP DATA SHOW NEARLY 30 KTS OF MIDLEVEL FLOW AND MODESTLY VEERING
WINDS WITH HEIGHT...SUPPORTIVE FOR ORGANIZED TSTM. COVERAGE OF TSTMS
IS SOMEWHAT UNCERTAIN GIVEN RELATIVELY WEAK FORCING FOR ASCENT...BUT
WITH THE POTENTIAL FOR LARGE HAIL AND DMGG WIND GUSTS...A WW MAY BE
REQUIRED SHOULD TRENDS CONTINUE TO INCREASE.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...ALY...BGM...BUF...
LAT...LON 41997433 42067611 42277755 42697790 43147756 43197706
43027555 42987423 42957307 42897266 42677229 42257234
41717280 41997433
000
ACUS11 KWNS 211655
SWOMCD
SPC MCD 211654
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-211800-
MESOSCALE DISCUSSION 0751
NWS STORM PREDICTION CENTER NORMAN OK
1154 AM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN/CNTRL NY...SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211654Z - 211800Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...TSTMS SHOULD CONTINUE INCREASING IN INTENSITY...PRIMARILY
FOCUSED ALONG/S OF A QUASI-STATIONARY FRONT...ACROSS PORTIONS OF
WRN/CNTRL NY AND INTO SRN NEW ENGLAND THIS AFTERNOON. THE PRIMARY
THREATS WILL BE DMGG WIND GUSTS AND LARGE HAIL. A WW MAY BE NEEDED
IF CONVECTIVE TRENDS CONTINUE TO INCREASE.
DISCUSSION...SUBJECTIVE SFC ANALYSIS FROM 16Z PLACES A
QUASI-STATIONARY FRONT FROM NEAR ROC-ALB. A FEW STORMS HAVE RECENTLY
INITIATED ALONG THIS FRONT...LIKELY IN RESPONSE TO WEAK LOW-LEVEL
CONVERGENCE...WEAKENING CONVECTIVE INHIBITION...AND MODEST MIDLEVEL
MOISTENING/ASCENT AS NOTED ON WATER VAPOR. MODIFIED 12Z SOUNDINGS
FROM BOTH BUF AND ALB SUGGEST AMPLE INSTABILITY FOR THE DEVELOPMENT
OF STRONG-SVR TSTMS...WITH MLCAPE VALUES LIKELY EXCEEDING 2000
J/KG...GIVEN THE PRESENCE OF MODERATELY STEEP MIDLEVEL LAPSE RATES
AND RICH LOW-LEVEL MOISTURE. ADDITIONALLY...BOTH SOUNDING AND RECENT
VWP DATA SHOW NEARLY 30 KTS OF MIDLEVEL FLOW AND MODESTLY VEERING
WINDS WITH HEIGHT...SUPPORTIVE FOR ORGANIZED TSTM. COVERAGE OF TSTMS
IS SOMEWHAT UNCERTAIN GIVEN RELATIVELY WEAK FORCING FOR ASCENT...BUT
WITH THE POTENTIAL FOR LARGE HAIL AND DMGG WIND GUSTS...A WW MAY BE
REQUIRED SHOULD TRENDS CONTINUE TO INCREASE.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...ALY...BGM...BUF...
LAT...LON 41997433 42067611 42277755 42697790 43147756 43197706
43027555 42987423 42957307 42897266 42677229 42257234
41717280 41997433
000
ACUS11 KWNS 211655
SWOMCD
SPC MCD 211654
NHZ000-MAZ000-CTZ000-VTZ000-NYZ000-211800-
MESOSCALE DISCUSSION 0751
NWS STORM PREDICTION CENTER NORMAN OK
1154 AM CDT TUE MAY 21 2013
AREAS AFFECTED...WRN/CNTRL NY...SRN NEW ENGLAND
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211654Z - 211800Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...TSTMS SHOULD CONTINUE INCREASING IN INTENSITY...PRIMARILY
FOCUSED ALONG/S OF A QUASI-STATIONARY FRONT...ACROSS PORTIONS OF
WRN/CNTRL NY AND INTO SRN NEW ENGLAND THIS AFTERNOON. THE PRIMARY
THREATS WILL BE DMGG WIND GUSTS AND LARGE HAIL. A WW MAY BE NEEDED
IF CONVECTIVE TRENDS CONTINUE TO INCREASE.
DISCUSSION...SUBJECTIVE SFC ANALYSIS FROM 16Z PLACES A
QUASI-STATIONARY FRONT FROM NEAR ROC-ALB. A FEW STORMS HAVE RECENTLY
INITIATED ALONG THIS FRONT...LIKELY IN RESPONSE TO WEAK LOW-LEVEL
CONVERGENCE...WEAKENING CONVECTIVE INHIBITION...AND MODEST MIDLEVEL
MOISTENING/ASCENT AS NOTED ON WATER VAPOR. MODIFIED 12Z SOUNDINGS
FROM BOTH BUF AND ALB SUGGEST AMPLE INSTABILITY FOR THE DEVELOPMENT
OF STRONG-SVR TSTMS...WITH MLCAPE VALUES LIKELY EXCEEDING 2000
J/KG...GIVEN THE PRESENCE OF MODERATELY STEEP MIDLEVEL LAPSE RATES
AND RICH LOW-LEVEL MOISTURE. ADDITIONALLY...BOTH SOUNDING AND RECENT
VWP DATA SHOW NEARLY 30 KTS OF MIDLEVEL FLOW AND MODESTLY VEERING
WINDS WITH HEIGHT...SUPPORTIVE FOR ORGANIZED TSTM. COVERAGE OF TSTMS
IS SOMEWHAT UNCERTAIN GIVEN RELATIVELY WEAK FORCING FOR ASCENT...BUT
WITH THE POTENTIAL FOR LARGE HAIL AND DMGG WIND GUSTS...A WW MAY BE
REQUIRED SHOULD TRENDS CONTINUE TO INCREASE.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...BOX...ALY...BGM...BUF...
LAT...LON 41997433 42067611 42277755 42697790 43147756 43197706
43027555 42987423 42957307 42897266 42677229 42257234
41717280 41997433
000
ACUS01 KWNS 211630
SWODY1
SPC AC 211628
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1128 AM CDT TUE MAY 21 2013
VALID 211630Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS FOR N-CNTRL/NERN TX...SRN
AR...NWRN LA...FAR SERN OK...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN PLAINS TO THE
TN/OH VALLEYS AND THE LOWER GREAT LAKES/NORTHEAST...
...SUBSTANTIAL SEVERE WEATHER EXPECTED ACROSS N-CNTRL TX TO THE
ARKLATEX THIS AFTERNOON AND EVENING...
..SRN PLAINS TO LOWER MS VALLEY...
SIGNIFICANT SEVERE WEATHER EPISODE INITIALLY UNFOLDING ACROSS THE
RED RIVER WITH SUPERCELLS PRODUCING LARGE HAIL ALONG AND N OF THE
COMPOSITE OUTFLOW/COLD FRONT PUSHING SWD FROM THE BIG COUNTRY TO FAR
SERN OK AHEAD OF A WELL-DEFINED SHORTWAVE TROUGH OVER THE SRN HIGH
PLAINS. AIR MASS S OF THE BOUNDARY IS BECOMING STRONGLY UNSTABLE AS
GRADUAL SURFACE HEATING CONTINUES AMIDST LOWEST 100 MB MEAN MIXING
RATIOS OF 14-17 G/KG AND 700-500 MB LAPSE RATES OF 8 TO 9.5 DEG C/KM
SAMPLED IN ALL REGIONAL 12Z RAOBS. AS MLCIN IS MINIMIZED ALONG THE
DRYLINE MIXING EWD ACROSS THE EDWARDS PLATEAU...ADDITIONAL SUPERCELL
DEVELOPMENT IS ANTICIPATED WITH SWD EXTENT.
A BELT OF 50-60 KT MID-LEVEL SWLYS ATTENDANT TO THE COMPACT
SHORTWAVE TROUGH WILL PROMOTE RISKS FOR ALL SEVERE TYPES /SOME OF
WHICH WILL BE SIGNIFICANT/. MORNING CONVECTION-ALLOWING WRF AND HRRR
SIMULATIONS ARE INSISTENT THAT UPSCALE GROWTH WILL OCCUR THROUGHOUT
THE AFTERNOON. GIVEN THE DEGREE OF INSTABILITY...BUOYANCY AND
SHEAR...SETUP MAY YIELD A DERECHO ACCELERATING EWD TOWARDS THE
ARKLATEX REGION BY EARLY EVENING. HERE TOO...THE STRONGEST LOW-LEVEL
S/SWLYS WILL REMAIN...PROMOTING EMBEDDED MESOVORTICES CAPABLE OF
PRODUCING A COUPLE OF SIGNIFICANT TORNADOES. OTHERWISE...POTENTIAL
DOES EXIST FOR WIDESPREAD/DESTRUCTIVE DAMAGING WIND GUSTS.
...TN VALLEY TO THE LOWER GREAT LAKES/NORTHEAST...
A BROAD AREA OF ORGANIZED SEVERE POTENTIAL IS EXPECTED ALONG THE ERN
EXTENT OF THE ELEVATED MIXED LAYER PLUME SAMPLED IN 12Z RAOBS. WITH
ROBUST HEATING...MODERATE TO STRONG INSTABILITY IS ANTICIPATED...BUT
MOST OF THE REGION WILL REMAIN ON THE FRINGE OF SUFFICIENT
DEEP-LAYER SHEAR FOR SUPERCELLS. THREE ZONES OF FOCUS FOR SUSTAINED
CONVECTION ARE APPARENT. ONE WILL BE DOWNSTREAM OF AN ONGOING
CLUSTER ACROSS WRN TN. THE OTHERS SHOULD BE ALONG A QUASI-STATIONARY
FRONT BISECTING NY INTO SRN NEW ENGLAND AND PERHAPS IN ASSOCIATION
WITH A WEAK MCV MOVING INTO LOWER MI. MULTICELL CLUSTERS AND A FEW
SUPERCELLS WILL BE PRIMARILY CAPABLE OF ISOLATED DAMAGING WINDS AND
SEVERE HAIL.
..GRAMS/ROGERS.. 05/21/2013
000
ACUS01 KWNS 211630
SWODY1
SPC AC 211628
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1128 AM CDT TUE MAY 21 2013
VALID 211630Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS FOR N-CNTRL/NERN TX...SRN
AR...NWRN LA...FAR SERN OK...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN PLAINS TO THE
TN/OH VALLEYS AND THE LOWER GREAT LAKES/NORTHEAST...
...SUBSTANTIAL SEVERE WEATHER EXPECTED ACROSS N-CNTRL TX TO THE
ARKLATEX THIS AFTERNOON AND EVENING...
..SRN PLAINS TO LOWER MS VALLEY...
SIGNIFICANT SEVERE WEATHER EPISODE INITIALLY UNFOLDING ACROSS THE
RED RIVER WITH SUPERCELLS PRODUCING LARGE HAIL ALONG AND N OF THE
COMPOSITE OUTFLOW/COLD FRONT PUSHING SWD FROM THE BIG COUNTRY TO FAR
SERN OK AHEAD OF A WELL-DEFINED SHORTWAVE TROUGH OVER THE SRN HIGH
PLAINS. AIR MASS S OF THE BOUNDARY IS BECOMING STRONGLY UNSTABLE AS
GRADUAL SURFACE HEATING CONTINUES AMIDST LOWEST 100 MB MEAN MIXING
RATIOS OF 14-17 G/KG AND 700-500 MB LAPSE RATES OF 8 TO 9.5 DEG C/KM
SAMPLED IN ALL REGIONAL 12Z RAOBS. AS MLCIN IS MINIMIZED ALONG THE
DRYLINE MIXING EWD ACROSS THE EDWARDS PLATEAU...ADDITIONAL SUPERCELL
DEVELOPMENT IS ANTICIPATED WITH SWD EXTENT.
A BELT OF 50-60 KT MID-LEVEL SWLYS ATTENDANT TO THE COMPACT
SHORTWAVE TROUGH WILL PROMOTE RISKS FOR ALL SEVERE TYPES /SOME OF
WHICH WILL BE SIGNIFICANT/. MORNING CONVECTION-ALLOWING WRF AND HRRR
SIMULATIONS ARE INSISTENT THAT UPSCALE GROWTH WILL OCCUR THROUGHOUT
THE AFTERNOON. GIVEN THE DEGREE OF INSTABILITY...BUOYANCY AND
SHEAR...SETUP MAY YIELD A DERECHO ACCELERATING EWD TOWARDS THE
ARKLATEX REGION BY EARLY EVENING. HERE TOO...THE STRONGEST LOW-LEVEL
S/SWLYS WILL REMAIN...PROMOTING EMBEDDED MESOVORTICES CAPABLE OF
PRODUCING A COUPLE OF SIGNIFICANT TORNADOES. OTHERWISE...POTENTIAL
DOES EXIST FOR WIDESPREAD/DESTRUCTIVE DAMAGING WIND GUSTS.
...TN VALLEY TO THE LOWER GREAT LAKES/NORTHEAST...
A BROAD AREA OF ORGANIZED SEVERE POTENTIAL IS EXPECTED ALONG THE ERN
EXTENT OF THE ELEVATED MIXED LAYER PLUME SAMPLED IN 12Z RAOBS. WITH
ROBUST HEATING...MODERATE TO STRONG INSTABILITY IS ANTICIPATED...BUT
MOST OF THE REGION WILL REMAIN ON THE FRINGE OF SUFFICIENT
DEEP-LAYER SHEAR FOR SUPERCELLS. THREE ZONES OF FOCUS FOR SUSTAINED
CONVECTION ARE APPARENT. ONE WILL BE DOWNSTREAM OF AN ONGOING
CLUSTER ACROSS WRN TN. THE OTHERS SHOULD BE ALONG A QUASI-STATIONARY
FRONT BISECTING NY INTO SRN NEW ENGLAND AND PERHAPS IN ASSOCIATION
WITH A WEAK MCV MOVING INTO LOWER MI. MULTICELL CLUSTERS AND A FEW
SUPERCELLS WILL BE PRIMARILY CAPABLE OF ISOLATED DAMAGING WINDS AND
SEVERE HAIL.
..GRAMS/ROGERS.. 05/21/2013
000
ACUS11 KWNS 211627
SWOMCD
SPC MCD 211627
KYZ000-TNZ000-211730-
MESOSCALE DISCUSSION 0750
NWS STORM PREDICTION CENTER NORMAN OK
1127 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MIDDLE TN...SRN KY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211627Z - 211730Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LOOSELY ORGANIZED QLCS OVER WRN TN SHOULD AT LEAST
MAINTAIN CURRENT INTENSITY OR POSSIBLY STRENGTHEN WITH EWD
PROGRESSION INTO MIDDLE TN AND SRN KY. WITH STRONG
HEATING/DESTABILIZATION DOWNSTREAM BECOMING MORE FAVORABLE FOR SFC
BASED STORMS...A THREAT FOR STRONG-SVR WIND GUSTS COULD EVOLVE.
TRENDS WILL BE MONITORED FOR A POSSIBLE WW.
DISCUSSION...RECENT RADAR MOSAIC SHOWS A LOOSELY ORGANIZED QLCS
POSITIONED ROUGHLY FROM CKV TO 40 S MKL AS OF 1615Z. ALTHOUGH
ASCENT/NEW CELL DEVELOPMENT DOES NOT APPEAR TO BE STRONGLY FOCUSED
ALONG THE LEADING EDGE OF THE COLD POOL ASSOCIATED WITH THIS
LINE...SEVERAL EMBEDDED STRONG CELLS WERE NOTED. ADDITIONAL TSTM
DEVELOPMENT APPEARS LIKELY OVER THE NEXT FEW HRS GIVEN MUCAPE VALUES
NEAR 2000 J/KG...PARTICULARLY ALONG THE INTERSECTION OF A REMNANT
OUTFLOW BOUNDARY ORIENTED W-E FROM EARLIER CONVECTION.
ADDITIONALLY...AN INCREASING THREAT FOR STRONG-SVR WIND GUSTS AND
SMALL-MARGINALLY SVR HAIL MAY EVOLVE OUT OF THIS LINE...AS SFC OBS
ARE NEARING THE CONVECTIVE TEMPERATURE IN THE LOW 80S F PER MODIFIED
12Z BNA SOUNDING...BECOMING MORE FAVORABLE FOR SFC-BASED PARCELS.
PRIMARY UNCERTAINTY SURROUNDS THE DEGREE OF ORGANIZATION AND
SUBSEQUENT AREAL COVERAGE OF ANY DMGG WIND THREAT THAT MAY
EVOLVE...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG...
LAT...LON 35038683 35038752 35088817 36398735 36948711 37168579
37078461 36978432 36198425 35028516 35038683
000
ACUS11 KWNS 211627
SWOMCD
SPC MCD 211627
KYZ000-TNZ000-211730-
MESOSCALE DISCUSSION 0750
NWS STORM PREDICTION CENTER NORMAN OK
1127 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MIDDLE TN...SRN KY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211627Z - 211730Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LOOSELY ORGANIZED QLCS OVER WRN TN SHOULD AT LEAST
MAINTAIN CURRENT INTENSITY OR POSSIBLY STRENGTHEN WITH EWD
PROGRESSION INTO MIDDLE TN AND SRN KY. WITH STRONG
HEATING/DESTABILIZATION DOWNSTREAM BECOMING MORE FAVORABLE FOR SFC
BASED STORMS...A THREAT FOR STRONG-SVR WIND GUSTS COULD EVOLVE.
TRENDS WILL BE MONITORED FOR A POSSIBLE WW.
DISCUSSION...RECENT RADAR MOSAIC SHOWS A LOOSELY ORGANIZED QLCS
POSITIONED ROUGHLY FROM CKV TO 40 S MKL AS OF 1615Z. ALTHOUGH
ASCENT/NEW CELL DEVELOPMENT DOES NOT APPEAR TO BE STRONGLY FOCUSED
ALONG THE LEADING EDGE OF THE COLD POOL ASSOCIATED WITH THIS
LINE...SEVERAL EMBEDDED STRONG CELLS WERE NOTED. ADDITIONAL TSTM
DEVELOPMENT APPEARS LIKELY OVER THE NEXT FEW HRS GIVEN MUCAPE VALUES
NEAR 2000 J/KG...PARTICULARLY ALONG THE INTERSECTION OF A REMNANT
OUTFLOW BOUNDARY ORIENTED W-E FROM EARLIER CONVECTION.
ADDITIONALLY...AN INCREASING THREAT FOR STRONG-SVR WIND GUSTS AND
SMALL-MARGINALLY SVR HAIL MAY EVOLVE OUT OF THIS LINE...AS SFC OBS
ARE NEARING THE CONVECTIVE TEMPERATURE IN THE LOW 80S F PER MODIFIED
12Z BNA SOUNDING...BECOMING MORE FAVORABLE FOR SFC-BASED PARCELS.
PRIMARY UNCERTAINTY SURROUNDS THE DEGREE OF ORGANIZATION AND
SUBSEQUENT AREAL COVERAGE OF ANY DMGG WIND THREAT THAT MAY
EVOLVE...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG...
LAT...LON 35038683 35038752 35088817 36398735 36948711 37168579
37078461 36978432 36198425 35028516 35038683
000
ACUS11 KWNS 211627
SWOMCD
SPC MCD 211627
KYZ000-TNZ000-211730-
MESOSCALE DISCUSSION 0750
NWS STORM PREDICTION CENTER NORMAN OK
1127 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MIDDLE TN...SRN KY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211627Z - 211730Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LOOSELY ORGANIZED QLCS OVER WRN TN SHOULD AT LEAST
MAINTAIN CURRENT INTENSITY OR POSSIBLY STRENGTHEN WITH EWD
PROGRESSION INTO MIDDLE TN AND SRN KY. WITH STRONG
HEATING/DESTABILIZATION DOWNSTREAM BECOMING MORE FAVORABLE FOR SFC
BASED STORMS...A THREAT FOR STRONG-SVR WIND GUSTS COULD EVOLVE.
TRENDS WILL BE MONITORED FOR A POSSIBLE WW.
DISCUSSION...RECENT RADAR MOSAIC SHOWS A LOOSELY ORGANIZED QLCS
POSITIONED ROUGHLY FROM CKV TO 40 S MKL AS OF 1615Z. ALTHOUGH
ASCENT/NEW CELL DEVELOPMENT DOES NOT APPEAR TO BE STRONGLY FOCUSED
ALONG THE LEADING EDGE OF THE COLD POOL ASSOCIATED WITH THIS
LINE...SEVERAL EMBEDDED STRONG CELLS WERE NOTED. ADDITIONAL TSTM
DEVELOPMENT APPEARS LIKELY OVER THE NEXT FEW HRS GIVEN MUCAPE VALUES
NEAR 2000 J/KG...PARTICULARLY ALONG THE INTERSECTION OF A REMNANT
OUTFLOW BOUNDARY ORIENTED W-E FROM EARLIER CONVECTION.
ADDITIONALLY...AN INCREASING THREAT FOR STRONG-SVR WIND GUSTS AND
SMALL-MARGINALLY SVR HAIL MAY EVOLVE OUT OF THIS LINE...AS SFC OBS
ARE NEARING THE CONVECTIVE TEMPERATURE IN THE LOW 80S F PER MODIFIED
12Z BNA SOUNDING...BECOMING MORE FAVORABLE FOR SFC-BASED PARCELS.
PRIMARY UNCERTAINTY SURROUNDS THE DEGREE OF ORGANIZATION AND
SUBSEQUENT AREAL COVERAGE OF ANY DMGG WIND THREAT THAT MAY
EVOLVE...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW.
..ROGERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG...
LAT...LON 35038683 35038752 35088817 36398735 36948711 37168579
37078461 36978432 36198425 35028516 35038683
000
ACUS11 KWNS 211509
SWOMCD
SPC MCD 211509
TXZ000-ARZ000-OKZ000-211645-
MESOSCALE DISCUSSION 0749
NWS STORM PREDICTION CENTER NORMAN OK
1009 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211509Z - 211645Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...STORMS WILL INCREASE IN COVERAGE AND INTENSITY OVER THE
NEXT 1-2 HRS...AND PARTICULARLY DAMAGING WINDS ARE EXPECTED TO
AFFECT MUCH OF NRN TX. IN ADDITION...A FEW TORNADOES AND VERY LARGE
HAIL WILL ALL BE POSSIBLE. A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...AN OUTFLOW BOUNDARY CURRENTLY EXTENDS FROM WRN AR WWD
ALONG THE RED RIVER TO JUST W OF ABILENE TX...JOINING WITH A
DEVELOPING COLD FRONT WHICH WILL CONTINUE SWD ACROSS W TX. TO THE
E...AN EXTREMELY MOIST AND UNSTABLE ATMOSPHERE WAS IN PLACE...WITH
MIDLEVEL LAPSE RATES OF 8.0-9.0 C/KM.
STORMS WILL RAPIDLY DEVELOP ALONG THE ADVANCING COLD FRONT WHICH
ALSO INTERSECTS THE OUTFLOW BOUNDARY IN THE NEXT FEW HOURS...AND ARE
EXPECTED TO QUICKLY GROW UPSCALE INTO A DAMAGING MCS. WIND GUSTS
OVER HURRICANE FORCE...WIND DRIVEN HAIL...AND A FEW TORNADOES WILL
BE POSSIBLE AS THE SYSTEM MATURES AND FORWARD PROPAGATES ACROSS A
LARGE PART OF NRN TX AND INTO THE ARKLATEX THIS EVENING.
ALTHOUGH MAINLY A LINEAR STORM MODE IS EVENTUALLY EXPECTED...INITIAL
DEVELOPMENT MAY BE SUPERCELLS WITH AN ENHANCED TORNADO THREAT. WHEN
STORMS DO MERGE...THERE WILL LIKELY BE AREAS OF ROTATION EMBEDDED
WITHIN THE ADVANCING LINE...PERHAPS PRODUCING SWATHS OF PARTICULARLY
DAMAGING WINDS.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...HGX...FWD...OUN...SJT...
LAT...LON 31970006 32929962 33939680 33899492 33579436 33179426
32169421 31459469 31169556 31329716 31479905 31970006
000
ACUS11 KWNS 211509
SWOMCD
SPC MCD 211509
TXZ000-ARZ000-OKZ000-211645-
MESOSCALE DISCUSSION 0749
NWS STORM PREDICTION CENTER NORMAN OK
1009 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211509Z - 211645Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...STORMS WILL INCREASE IN COVERAGE AND INTENSITY OVER THE
NEXT 1-2 HRS...AND PARTICULARLY DAMAGING WINDS ARE EXPECTED TO
AFFECT MUCH OF NRN TX. IN ADDITION...A FEW TORNADOES AND VERY LARGE
HAIL WILL ALL BE POSSIBLE. A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...AN OUTFLOW BOUNDARY CURRENTLY EXTENDS FROM WRN AR WWD
ALONG THE RED RIVER TO JUST W OF ABILENE TX...JOINING WITH A
DEVELOPING COLD FRONT WHICH WILL CONTINUE SWD ACROSS W TX. TO THE
E...AN EXTREMELY MOIST AND UNSTABLE ATMOSPHERE WAS IN PLACE...WITH
MIDLEVEL LAPSE RATES OF 8.0-9.0 C/KM.
STORMS WILL RAPIDLY DEVELOP ALONG THE ADVANCING COLD FRONT WHICH
ALSO INTERSECTS THE OUTFLOW BOUNDARY IN THE NEXT FEW HOURS...AND ARE
EXPECTED TO QUICKLY GROW UPSCALE INTO A DAMAGING MCS. WIND GUSTS
OVER HURRICANE FORCE...WIND DRIVEN HAIL...AND A FEW TORNADOES WILL
BE POSSIBLE AS THE SYSTEM MATURES AND FORWARD PROPAGATES ACROSS A
LARGE PART OF NRN TX AND INTO THE ARKLATEX THIS EVENING.
ALTHOUGH MAINLY A LINEAR STORM MODE IS EVENTUALLY EXPECTED...INITIAL
DEVELOPMENT MAY BE SUPERCELLS WITH AN ENHANCED TORNADO THREAT. WHEN
STORMS DO MERGE...THERE WILL LIKELY BE AREAS OF ROTATION EMBEDDED
WITHIN THE ADVANCING LINE...PERHAPS PRODUCING SWATHS OF PARTICULARLY
DAMAGING WINDS.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...HGX...FWD...OUN...SJT...
LAT...LON 31970006 32929962 33939680 33899492 33579436 33179426
32169421 31459469 31169556 31329716 31479905 31970006
000
ACUS11 KWNS 211509
SWOMCD
SPC MCD 211509
TXZ000-ARZ000-OKZ000-211645-
MESOSCALE DISCUSSION 0749
NWS STORM PREDICTION CENTER NORMAN OK
1009 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 211509Z - 211645Z
PROBABILITY OF WATCH ISSUANCE...95 PERCENT
SUMMARY...STORMS WILL INCREASE IN COVERAGE AND INTENSITY OVER THE
NEXT 1-2 HRS...AND PARTICULARLY DAMAGING WINDS ARE EXPECTED TO
AFFECT MUCH OF NRN TX. IN ADDITION...A FEW TORNADOES AND VERY LARGE
HAIL WILL ALL BE POSSIBLE. A WATCH WILL BE ISSUED SHORTLY.
DISCUSSION...AN OUTFLOW BOUNDARY CURRENTLY EXTENDS FROM WRN AR WWD
ALONG THE RED RIVER TO JUST W OF ABILENE TX...JOINING WITH A
DEVELOPING COLD FRONT WHICH WILL CONTINUE SWD ACROSS W TX. TO THE
E...AN EXTREMELY MOIST AND UNSTABLE ATMOSPHERE WAS IN PLACE...WITH
MIDLEVEL LAPSE RATES OF 8.0-9.0 C/KM.
STORMS WILL RAPIDLY DEVELOP ALONG THE ADVANCING COLD FRONT WHICH
ALSO INTERSECTS THE OUTFLOW BOUNDARY IN THE NEXT FEW HOURS...AND ARE
EXPECTED TO QUICKLY GROW UPSCALE INTO A DAMAGING MCS. WIND GUSTS
OVER HURRICANE FORCE...WIND DRIVEN HAIL...AND A FEW TORNADOES WILL
BE POSSIBLE AS THE SYSTEM MATURES AND FORWARD PROPAGATES ACROSS A
LARGE PART OF NRN TX AND INTO THE ARKLATEX THIS EVENING.
ALTHOUGH MAINLY A LINEAR STORM MODE IS EVENTUALLY EXPECTED...INITIAL
DEVELOPMENT MAY BE SUPERCELLS WITH AN ENHANCED TORNADO THREAT. WHEN
STORMS DO MERGE...THERE WILL LIKELY BE AREAS OF ROTATION EMBEDDED
WITHIN THE ADVANCING LINE...PERHAPS PRODUCING SWATHS OF PARTICULARLY
DAMAGING WINDS.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SHV...TSA...HGX...FWD...OUN...SJT...
LAT...LON 31970006 32929962 33939680 33899492 33579436 33179426
32169421 31459469 31169556 31329716 31479905 31970006
000
ACUS11 KWNS 211447
SWOMCD
SPC MCD 211446
OKZ000-TXZ000-211715-
MESOSCALE DISCUSSION 0748
NWS STORM PREDICTION CENTER NORMAN OK
0946 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF OK
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211446Z - 211715Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCATTERED STORMS WILL PERSIST ACROSS MUCH OF OK. LOCALLY
HEAVY RAIN AND HAIL TO THE SIZE OF QUARTERS WILL BE POSSIBLE.
HOWEVER...COVERAGE OF HAIL MAY NOT BE ENOUGH FOR A WATCH.
DISCUSSION...A STRONG SHORTWAVE TROUGH CONTINUES TO EJECT EWD ACROSS
THE TX PANHANDLE AND INTO WRN OK THIS MORNING WITH SCATTERED STRONG
TO SEVERE HAIL STORMS BEGINNING TO FORM NEAR CHILDRESS TX. THESE
STORMS ARE LIKELY ROOTED NEAR 700 MB...WELL ELEVATED ATOP THE
DEEPENING SURFACE COOL LAYER. FRONTOGENETICAL FORCING AND WARM
ADVECTION AT 700 ARE CURRENTLY CENTERED OVER THE TX/OK BORDER AND
WILL SPREAD EWD ACROSS THE BODY OF OK.
THE 12Z AMA AND OUN SOUNDINGS BOTH SHOW INSTABILITY ROOTED AT 700
MB...AND COOLING ALOFT FROM THE W WILL OVERSPREAD OK. FORECAST
SOUNDINGS FROM MULTIPLE MODELS INDICATE THAT DEEP LAYER SHEAR IN THE
CLOUD LAYER WILL AT LEAST BE MARGINALLY FAVORABLE FOR A FEW LONGER
LIVED CELLS CAPABLE OF HAIL...POSSIBLY AFFECTING THE OKC METRO AREA
LATE MORNING/EARLY AFTERNOON.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...OUN...LUB...AMA...
LAT...LON 35030024 35399933 35899782 36239650 36349551 35839511
34929525 34649600 34399732 34269848 34299939 34329984
34500020 35030024
000
ACUS11 KWNS 211447
SWOMCD
SPC MCD 211446
OKZ000-TXZ000-211715-
MESOSCALE DISCUSSION 0748
NWS STORM PREDICTION CENTER NORMAN OK
0946 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF OK
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211446Z - 211715Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCATTERED STORMS WILL PERSIST ACROSS MUCH OF OK. LOCALLY
HEAVY RAIN AND HAIL TO THE SIZE OF QUARTERS WILL BE POSSIBLE.
HOWEVER...COVERAGE OF HAIL MAY NOT BE ENOUGH FOR A WATCH.
DISCUSSION...A STRONG SHORTWAVE TROUGH CONTINUES TO EJECT EWD ACROSS
THE TX PANHANDLE AND INTO WRN OK THIS MORNING WITH SCATTERED STRONG
TO SEVERE HAIL STORMS BEGINNING TO FORM NEAR CHILDRESS TX. THESE
STORMS ARE LIKELY ROOTED NEAR 700 MB...WELL ELEVATED ATOP THE
DEEPENING SURFACE COOL LAYER. FRONTOGENETICAL FORCING AND WARM
ADVECTION AT 700 ARE CURRENTLY CENTERED OVER THE TX/OK BORDER AND
WILL SPREAD EWD ACROSS THE BODY OF OK.
THE 12Z AMA AND OUN SOUNDINGS BOTH SHOW INSTABILITY ROOTED AT 700
MB...AND COOLING ALOFT FROM THE W WILL OVERSPREAD OK. FORECAST
SOUNDINGS FROM MULTIPLE MODELS INDICATE THAT DEEP LAYER SHEAR IN THE
CLOUD LAYER WILL AT LEAST BE MARGINALLY FAVORABLE FOR A FEW LONGER
LIVED CELLS CAPABLE OF HAIL...POSSIBLY AFFECTING THE OKC METRO AREA
LATE MORNING/EARLY AFTERNOON.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...OUN...LUB...AMA...
LAT...LON 35030024 35399933 35899782 36239650 36349551 35839511
34929525 34649600 34399732 34269848 34299939 34329984
34500020 35030024
000
ACUS11 KWNS 211447
SWOMCD
SPC MCD 211446
OKZ000-TXZ000-211715-
MESOSCALE DISCUSSION 0748
NWS STORM PREDICTION CENTER NORMAN OK
0946 AM CDT TUE MAY 21 2013
AREAS AFFECTED...MUCH OF OK
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211446Z - 211715Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SCATTERED STORMS WILL PERSIST ACROSS MUCH OF OK. LOCALLY
HEAVY RAIN AND HAIL TO THE SIZE OF QUARTERS WILL BE POSSIBLE.
HOWEVER...COVERAGE OF HAIL MAY NOT BE ENOUGH FOR A WATCH.
DISCUSSION...A STRONG SHORTWAVE TROUGH CONTINUES TO EJECT EWD ACROSS
THE TX PANHANDLE AND INTO WRN OK THIS MORNING WITH SCATTERED STRONG
TO SEVERE HAIL STORMS BEGINNING TO FORM NEAR CHILDRESS TX. THESE
STORMS ARE LIKELY ROOTED NEAR 700 MB...WELL ELEVATED ATOP THE
DEEPENING SURFACE COOL LAYER. FRONTOGENETICAL FORCING AND WARM
ADVECTION AT 700 ARE CURRENTLY CENTERED OVER THE TX/OK BORDER AND
WILL SPREAD EWD ACROSS THE BODY OF OK.
THE 12Z AMA AND OUN SOUNDINGS BOTH SHOW INSTABILITY ROOTED AT 700
MB...AND COOLING ALOFT FROM THE W WILL OVERSPREAD OK. FORECAST
SOUNDINGS FROM MULTIPLE MODELS INDICATE THAT DEEP LAYER SHEAR IN THE
CLOUD LAYER WILL AT LEAST BE MARGINALLY FAVORABLE FOR A FEW LONGER
LIVED CELLS CAPABLE OF HAIL...POSSIBLY AFFECTING THE OKC METRO AREA
LATE MORNING/EARLY AFTERNOON.
..JEWELL/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...OUN...LUB...AMA...
LAT...LON 35030024 35399933 35899782 36239650 36349551 35839511
34929525 34649600 34399732 34269848 34299939 34329984
34500020 35030024
000
ACUS11 KWNS 211313
SWOMCD
SPC MCD 211312
ARZ000-TXZ000-OKZ000-211445-
MESOSCALE DISCUSSION 0747
NWS STORM PREDICTION CENTER NORMAN OK
0812 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN OK AND NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211312Z - 211445Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...POTENTIAL EXISTS FOR ONGOING STORMS EXTENDING FROM EAST
CENTRAL THROUGH SOUTH CENTRAL OK TO WRN NORTH TX TO BECOME SURFACE
BASED LATER THIS MORNING. ISOLATED DAMAGING WINDS AND HAIL WILL BE
THE PRIMARY THREATS WITH THE ONGOING ACTIVITY...WITH AN INCREASE IN
THE SEVERE WEATHER THREAT LATER THIS MORNING...AND THE POTENTIAL FOR
A NEW WW.
DISCUSSION...MOSAIC RADAR IMAGERY THE LAST FEW HOURS INDICATED TSTMS
CONTINUED TO DEVELOP AND MOVE ENEWD ACROSS CENTRAL...ERN OK INTO
WEST CENTRAL AR...WHILE ADDITIONAL STORMS HAVE DEVELOPED SWWD
THROUGH SWRN OK TO WRN N TX. THE ENTIRE EXTENT OF THE TSTM ACTIVITY
APPEARS TO BE ELEVATED INCLUDING THE LATTER SWRN OK/WRN N TX STORMS
THAT HAVE TENDED TO BECOME UNDERCUT BY A SWD ADVANCING COLD FRONT.
INCREASING FORCING FOR ASCENT WITH AN APPROACHING SHORTWAVE TROUGH
AND LOW LEVEL WAA OVER N TX AND SRN OK WILL SUPPORT CONTINUED TSTM
DEVELOPMENT THROUGH THIS MORNING. VISIBLE SATELLITE IMAGERY SHOWS
THE LIKELIHOOD FOR ABUNDANT SURFACE HEATING ALONG AND SOUTH OF THE
RED RIVER...WHICH WILL FURTHER BOOST AN ALREADY MODERATELY UNSTABLE
ENVIRONMENT...WITH THE POTENTIAL FOR STORMS TO BECOME SURFACE BASED.
FURTHER STRENGTHENING OF WSWLY MIDLEVEL WINDS/BULK SHEAR WITH THE
APPROACH OF THE SRN HIGH PLAINS TROUGH WILL SUPPORT STORM
ORGANIZATION. SWLY SHEAR VECTORS ORIENTED PARALLEL TO THE ONGOING
STORMS AND NEW DEVELOPMENT WILL FAVOR LINE SEGMENTS/BOWS WITH
DAMAGING WINDS THE PRIMARY THREAT. HOWEVER...THE PRESENCE OF STEEP
MIDLEVEL LAPSE RATES /NEAR 9 C PER KM ON THE 12Z FORT WORTH TX
SOUNDING/ SUGGESTS HAIL WILL BE A THREAT AS WELL. THE LAST SEVERAL
HRRR RUNS FORECAST UPSCALE GROWTH FOR ONE OR MORE QLCS STRUCTURES
ACROSS SRN OK AND N TX LATER THIS MORNING INTO THE AFTERNOON.
..PETERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...FWD...OUN...
LAT...LON 33689911 34339817 34439719 34929613 34979448 34539441
33609449 33239508 33079575 33049663 33099747 33139810
33259875 33689911
000
ACUS11 KWNS 211313
SWOMCD
SPC MCD 211312
ARZ000-TXZ000-OKZ000-211445-
MESOSCALE DISCUSSION 0747
NWS STORM PREDICTION CENTER NORMAN OK
0812 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN OK AND NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211312Z - 211445Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...POTENTIAL EXISTS FOR ONGOING STORMS EXTENDING FROM EAST
CENTRAL THROUGH SOUTH CENTRAL OK TO WRN NORTH TX TO BECOME SURFACE
BASED LATER THIS MORNING. ISOLATED DAMAGING WINDS AND HAIL WILL BE
THE PRIMARY THREATS WITH THE ONGOING ACTIVITY...WITH AN INCREASE IN
THE SEVERE WEATHER THREAT LATER THIS MORNING...AND THE POTENTIAL FOR
A NEW WW.
DISCUSSION...MOSAIC RADAR IMAGERY THE LAST FEW HOURS INDICATED TSTMS
CONTINUED TO DEVELOP AND MOVE ENEWD ACROSS CENTRAL...ERN OK INTO
WEST CENTRAL AR...WHILE ADDITIONAL STORMS HAVE DEVELOPED SWWD
THROUGH SWRN OK TO WRN N TX. THE ENTIRE EXTENT OF THE TSTM ACTIVITY
APPEARS TO BE ELEVATED INCLUDING THE LATTER SWRN OK/WRN N TX STORMS
THAT HAVE TENDED TO BECOME UNDERCUT BY A SWD ADVANCING COLD FRONT.
INCREASING FORCING FOR ASCENT WITH AN APPROACHING SHORTWAVE TROUGH
AND LOW LEVEL WAA OVER N TX AND SRN OK WILL SUPPORT CONTINUED TSTM
DEVELOPMENT THROUGH THIS MORNING. VISIBLE SATELLITE IMAGERY SHOWS
THE LIKELIHOOD FOR ABUNDANT SURFACE HEATING ALONG AND SOUTH OF THE
RED RIVER...WHICH WILL FURTHER BOOST AN ALREADY MODERATELY UNSTABLE
ENVIRONMENT...WITH THE POTENTIAL FOR STORMS TO BECOME SURFACE BASED.
FURTHER STRENGTHENING OF WSWLY MIDLEVEL WINDS/BULK SHEAR WITH THE
APPROACH OF THE SRN HIGH PLAINS TROUGH WILL SUPPORT STORM
ORGANIZATION. SWLY SHEAR VECTORS ORIENTED PARALLEL TO THE ONGOING
STORMS AND NEW DEVELOPMENT WILL FAVOR LINE SEGMENTS/BOWS WITH
DAMAGING WINDS THE PRIMARY THREAT. HOWEVER...THE PRESENCE OF STEEP
MIDLEVEL LAPSE RATES /NEAR 9 C PER KM ON THE 12Z FORT WORTH TX
SOUNDING/ SUGGESTS HAIL WILL BE A THREAT AS WELL. THE LAST SEVERAL
HRRR RUNS FORECAST UPSCALE GROWTH FOR ONE OR MORE QLCS STRUCTURES
ACROSS SRN OK AND N TX LATER THIS MORNING INTO THE AFTERNOON.
..PETERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...FWD...OUN...
LAT...LON 33689911 34339817 34439719 34929613 34979448 34539441
33609449 33239508 33079575 33049663 33099747 33139810
33259875 33689911
000
ACUS11 KWNS 211313
SWOMCD
SPC MCD 211312
ARZ000-TXZ000-OKZ000-211445-
MESOSCALE DISCUSSION 0747
NWS STORM PREDICTION CENTER NORMAN OK
0812 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PARTS OF SRN OK AND NRN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211312Z - 211445Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...POTENTIAL EXISTS FOR ONGOING STORMS EXTENDING FROM EAST
CENTRAL THROUGH SOUTH CENTRAL OK TO WRN NORTH TX TO BECOME SURFACE
BASED LATER THIS MORNING. ISOLATED DAMAGING WINDS AND HAIL WILL BE
THE PRIMARY THREATS WITH THE ONGOING ACTIVITY...WITH AN INCREASE IN
THE SEVERE WEATHER THREAT LATER THIS MORNING...AND THE POTENTIAL FOR
A NEW WW.
DISCUSSION...MOSAIC RADAR IMAGERY THE LAST FEW HOURS INDICATED TSTMS
CONTINUED TO DEVELOP AND MOVE ENEWD ACROSS CENTRAL...ERN OK INTO
WEST CENTRAL AR...WHILE ADDITIONAL STORMS HAVE DEVELOPED SWWD
THROUGH SWRN OK TO WRN N TX. THE ENTIRE EXTENT OF THE TSTM ACTIVITY
APPEARS TO BE ELEVATED INCLUDING THE LATTER SWRN OK/WRN N TX STORMS
THAT HAVE TENDED TO BECOME UNDERCUT BY A SWD ADVANCING COLD FRONT.
INCREASING FORCING FOR ASCENT WITH AN APPROACHING SHORTWAVE TROUGH
AND LOW LEVEL WAA OVER N TX AND SRN OK WILL SUPPORT CONTINUED TSTM
DEVELOPMENT THROUGH THIS MORNING. VISIBLE SATELLITE IMAGERY SHOWS
THE LIKELIHOOD FOR ABUNDANT SURFACE HEATING ALONG AND SOUTH OF THE
RED RIVER...WHICH WILL FURTHER BOOST AN ALREADY MODERATELY UNSTABLE
ENVIRONMENT...WITH THE POTENTIAL FOR STORMS TO BECOME SURFACE BASED.
FURTHER STRENGTHENING OF WSWLY MIDLEVEL WINDS/BULK SHEAR WITH THE
APPROACH OF THE SRN HIGH PLAINS TROUGH WILL SUPPORT STORM
ORGANIZATION. SWLY SHEAR VECTORS ORIENTED PARALLEL TO THE ONGOING
STORMS AND NEW DEVELOPMENT WILL FAVOR LINE SEGMENTS/BOWS WITH
DAMAGING WINDS THE PRIMARY THREAT. HOWEVER...THE PRESENCE OF STEEP
MIDLEVEL LAPSE RATES /NEAR 9 C PER KM ON THE 12Z FORT WORTH TX
SOUNDING/ SUGGESTS HAIL WILL BE A THREAT AS WELL. THE LAST SEVERAL
HRRR RUNS FORECAST UPSCALE GROWTH FOR ONE OR MORE QLCS STRUCTURES
ACROSS SRN OK AND N TX LATER THIS MORNING INTO THE AFTERNOON.
..PETERS/KERR.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...FWD...OUN...
LAT...LON 33689911 34339817 34439719 34929613 34979448 34539441
33609449 33239508 33079575 33049663 33099747 33139810
33259875 33689911
000
ACUS11 KWNS 211247
SWOMCD
SPC MCD 211247
ALZ000-TNZ000-KYZ000-MSZ000-MOZ000-ARZ000-211345-
MESOSCALE DISCUSSION 0746
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CDT TUE MAY 21 2013
AREAS AFFECTED...FAR NE AR...WRN TX...NRN MS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211247Z - 211345Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LINE OF STORMS MOVING ACROSS NW AR THIS MORNING MAY
PRODUCE MARGINALLY SEVERE WIND GUSTS OF 50-60 MPH AS THEY TRACK EWD
TOWARD WRN TN/NRN MS. A WW IS NOT EXPECTED AT THIS TIME BUT TRENDS
WILL BE MONITORED.
DISCUSSION...THUNDERSTORM INTENSITY HAS INCREASED SOME THIS MORNING
ACROSS NW AR. AS THIS LINE OF ELEVATED CONVECTION TRACKS
EWD...MARGINALLY SEVERE WINDS ARE POSSIBLE. THE DOWNSTREAM
ENVIRONMENT HAS LIMITED SBCAPE DUE TO EARLY CAPPING AS INDICATED BY
12Z BNA RAOB. HOWEVER...MLCAPE VALUES AROUND 2500 J/KG COUPLED WITH
20-30 KT BULK SHEAR MAY ALLOW FOR CONTINUED ORGANIZATION AND A
LOW-END SEVERE THREAT. AT THIS TIME...NO OBSERVED SEVERE WIND GUSTS
HAVE BEEN NOTED. TRENDS WILL BE MONITORED FOR A POTENTIAL SEVERE WW
THIS MORNING.
..LEITMAN/HART.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...LZK...
LAT...LON 36399038 36578938 36548839 36238792 35618777 34918798
34168937 34259079 34619117 36399038
000
ACUS11 KWNS 211247
SWOMCD
SPC MCD 211247
ALZ000-TNZ000-KYZ000-MSZ000-MOZ000-ARZ000-211345-
MESOSCALE DISCUSSION 0746
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CDT TUE MAY 21 2013
AREAS AFFECTED...FAR NE AR...WRN TX...NRN MS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211247Z - 211345Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LINE OF STORMS MOVING ACROSS NW AR THIS MORNING MAY
PRODUCE MARGINALLY SEVERE WIND GUSTS OF 50-60 MPH AS THEY TRACK EWD
TOWARD WRN TN/NRN MS. A WW IS NOT EXPECTED AT THIS TIME BUT TRENDS
WILL BE MONITORED.
DISCUSSION...THUNDERSTORM INTENSITY HAS INCREASED SOME THIS MORNING
ACROSS NW AR. AS THIS LINE OF ELEVATED CONVECTION TRACKS
EWD...MARGINALLY SEVERE WINDS ARE POSSIBLE. THE DOWNSTREAM
ENVIRONMENT HAS LIMITED SBCAPE DUE TO EARLY CAPPING AS INDICATED BY
12Z BNA RAOB. HOWEVER...MLCAPE VALUES AROUND 2500 J/KG COUPLED WITH
20-30 KT BULK SHEAR MAY ALLOW FOR CONTINUED ORGANIZATION AND A
LOW-END SEVERE THREAT. AT THIS TIME...NO OBSERVED SEVERE WIND GUSTS
HAVE BEEN NOTED. TRENDS WILL BE MONITORED FOR A POTENTIAL SEVERE WW
THIS MORNING.
..LEITMAN/HART.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...LZK...
LAT...LON 36399038 36578938 36548839 36238792 35618777 34918798
34168937 34259079 34619117 36399038
000
ACUS11 KWNS 211247
SWOMCD
SPC MCD 211247
ALZ000-TNZ000-KYZ000-MSZ000-MOZ000-ARZ000-211345-
MESOSCALE DISCUSSION 0746
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CDT TUE MAY 21 2013
AREAS AFFECTED...FAR NE AR...WRN TX...NRN MS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 211247Z - 211345Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LINE OF STORMS MOVING ACROSS NW AR THIS MORNING MAY
PRODUCE MARGINALLY SEVERE WIND GUSTS OF 50-60 MPH AS THEY TRACK EWD
TOWARD WRN TN/NRN MS. A WW IS NOT EXPECTED AT THIS TIME BUT TRENDS
WILL BE MONITORED.
DISCUSSION...THUNDERSTORM INTENSITY HAS INCREASED SOME THIS MORNING
ACROSS NW AR. AS THIS LINE OF ELEVATED CONVECTION TRACKS
EWD...MARGINALLY SEVERE WINDS ARE POSSIBLE. THE DOWNSTREAM
ENVIRONMENT HAS LIMITED SBCAPE DUE TO EARLY CAPPING AS INDICATED BY
12Z BNA RAOB. HOWEVER...MLCAPE VALUES AROUND 2500 J/KG COUPLED WITH
20-30 KT BULK SHEAR MAY ALLOW FOR CONTINUED ORGANIZATION AND A
LOW-END SEVERE THREAT. AT THIS TIME...NO OBSERVED SEVERE WIND GUSTS
HAVE BEEN NOTED. TRENDS WILL BE MONITORED FOR A POTENTIAL SEVERE WW
THIS MORNING.
..LEITMAN/HART.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OHX...HUN...PAH...MEG...LZK...
LAT...LON 36399038 36578938 36548839 36238792 35618777 34918798
34168937 34259079 34619117 36399038
000
ACUS01 KWNS 211141
SWODY1
SPC AC 211139
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0639 AM CDT TUE MAY 21 2013
VALID 211300Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND EAST
TX...SOUTHEAST OK...NORTHWEST LA...AND WESTERN AR...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SOUTHERN PLAINS INTO
THE MID MS VALLEY AND GREAT LAKES STATES...
...TX/OK/AR/LA...
MORNING WATER VAPOR IMAGERY SHOWS A WELL-DEFINED UPPER TROUGH OVER
THE NM/TX BORDER. THIS FEATURE IS FORECAST TO TRACK EASTWARD INTO
THE SOUTHERN PLAINS TODAY...SETTING THE STAGE FOR ANOTHER ACTIVE DAY
OF SEVERE THUNDERSTORMS.
SCATTERED STRONG THUNDERSTORMS ARE ONGOING THIS MORNING ACROSS
SOUTHERN OK...IN A REGION OF LOW LEVEL WARM ADVECTION AND AHEAD OF A
SURFACE COLD FRONT. THESE STORMS APPEAR LIKELY TO INCREASE IN
COVERAGE THROUGH THE MORNING...SPREADING SOUTHEASTWARD INTO NORTH TX
AND WESTERN AR. AMPLE LOW LEVEL MOISTURE AND MODERATE CAPE VALUES
WILL POSE A RISK OF LARGE HAIL AND LOCALLY DAMAGING WINDS.
BY EARLY AFTERNOON...STRONG HEATING SOUTH OF THE STORMS WILL PROMOTE
FURTHER INTENSIFICATION ACROSS MUCH OF NORTH CENTRAL AND NORTHEAST
TX. STEEP MID LEVEL LAPSE RATES AND DEWPOINTS NEAR 70F WILL YIELD
MLCAPE VALUES OF 2000+ J/KG. AS THE UPPER TROUGH
APPROACHES...STRENGTHENING VERTICAL SHEAR SUGGESTS A RISK OF
DISCRETE SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES.
THE ACTIVITY IS FORECAST TO CONGEAL INTO LINES/CLUSTERS OF STORMS BY
EARLY EVENING SPREADING RAPIDLY EASTWARD INTO AR/LA. THESE STORMS
WILL LIKELY HAVE AN ENHANCED RISK OF WIDESPREAD DAMAGING WINDS.
...MO/IL NORTHWARD INTO LOWER MI...
MULTIPLE BANDS OF THUNDERSTORMS HAVE AFFECTED THE MID MS VALLEY
OVERNIGHT. THESE STORMS HAVE WEAKENED INSTABILITY AND ARE PROVIDING
UNCERTAINTY REGARDING THE COVERAGE/INTENSITY OF THUNDERSTORMS LATER
TODAY. HAVE MAINTAINED THE SLIGHT RISK AREA...BUT HAVE GENERALLY
DECREASED PROBABILITIES IN THESE REGIONS. THE AREA THAT APPEARS
MOST LIKELY TO SEE ISOLATED SEVERE STORMS LATER TODAY WOULD BE
ACROSS LOWER MI AS A SHORTWAVE TROUGH NOW OVER MO/IL ROTATES
NORTHEASTWARD.
..HART/LEITMAN.. 05/21/2013
000
ACUS01 KWNS 211141
SWODY1
SPC AC 211139
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0639 AM CDT TUE MAY 21 2013
VALID 211300Z - 221200Z
...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND EAST
TX...SOUTHEAST OK...NORTHWEST LA...AND WESTERN AR...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SOUTHERN PLAINS INTO
THE MID MS VALLEY AND GREAT LAKES STATES...
...TX/OK/AR/LA...
MORNING WATER VAPOR IMAGERY SHOWS A WELL-DEFINED UPPER TROUGH OVER
THE NM/TX BORDER. THIS FEATURE IS FORECAST TO TRACK EASTWARD INTO
THE SOUTHERN PLAINS TODAY...SETTING THE STAGE FOR ANOTHER ACTIVE DAY
OF SEVERE THUNDERSTORMS.
SCATTERED STRONG THUNDERSTORMS ARE ONGOING THIS MORNING ACROSS
SOUTHERN OK...IN A REGION OF LOW LEVEL WARM ADVECTION AND AHEAD OF A
SURFACE COLD FRONT. THESE STORMS APPEAR LIKELY TO INCREASE IN
COVERAGE THROUGH THE MORNING...SPREADING SOUTHEASTWARD INTO NORTH TX
AND WESTERN AR. AMPLE LOW LEVEL MOISTURE AND MODERATE CAPE VALUES
WILL POSE A RISK OF LARGE HAIL AND LOCALLY DAMAGING WINDS.
BY EARLY AFTERNOON...STRONG HEATING SOUTH OF THE STORMS WILL PROMOTE
FURTHER INTENSIFICATION ACROSS MUCH OF NORTH CENTRAL AND NORTHEAST
TX. STEEP MID LEVEL LAPSE RATES AND DEWPOINTS NEAR 70F WILL YIELD
MLCAPE VALUES OF 2000+ J/KG. AS THE UPPER TROUGH
APPROACHES...STRENGTHENING VERTICAL SHEAR SUGGESTS A RISK OF
DISCRETE SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES.
THE ACTIVITY IS FORECAST TO CONGEAL INTO LINES/CLUSTERS OF STORMS BY
EARLY EVENING SPREADING RAPIDLY EASTWARD INTO AR/LA. THESE STORMS
WILL LIKELY HAVE AN ENHANCED RISK OF WIDESPREAD DAMAGING WINDS.
...MO/IL NORTHWARD INTO LOWER MI...
MULTIPLE BANDS OF THUNDERSTORMS HAVE AFFECTED THE MID MS VALLEY
OVERNIGHT. THESE STORMS HAVE WEAKENED INSTABILITY AND ARE PROVIDING
UNCERTAINTY REGARDING THE COVERAGE/INTENSITY OF THUNDERSTORMS LATER
TODAY. HAVE MAINTAINED THE SLIGHT RISK AREA...BUT HAVE GENERALLY
DECREASED PROBABILITIES IN THESE REGIONS. THE AREA THAT APPEARS
MOST LIKELY TO SEE ISOLATED SEVERE STORMS LATER TODAY WOULD BE
ACROSS LOWER MI AS A SHORTWAVE TROUGH NOW OVER MO/IL ROTATES
NORTHEASTWARD.
..HART/LEITMAN.. 05/21/2013
000
ACUS11 KWNS 210921
SWOMCD
SPC MCD 210920
ARZ000-OKZ000-211015-
MESOSCALE DISCUSSION 0745
NWS STORM PREDICTION CENTER NORMAN OK
0420 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PART OF SRN/ERN OK INTO WEST CENTRAL AR
CONCERNING...SEVERE THUNDERSTORM WATCH 199...
VALID 210920Z - 211015Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 199
CONTINUES.
SUMMARY...AN ISOLATED HAIL THREAT CONTINUES ACROSS WW 199 INTO THE
EARLY MORNING...AS NEW STORMS DEVELOP FROM KIOWA COUNTY OK THROUGH
CENTRAL MCCLAIN/SRN CLEVELAND COUNTIES TO MCINTOSH COUNTY OK.
DISCUSSION...A BROAD WAA ZONE EXTENDING INTO SRN OK WITHIN THE NOSE
OF A 45-50 KT SSWLY LLJ COMBINED WITH A NWD INFLUX OF MODERATE
INSTABILITY SUGGESTS TSTM DEVELOPMENT WILL CONTINUE FROM W-E ACROSS
WW 199. EFFECTIVE BULK SHEAR UP TO 50 KT SUPPORTS STORM
ORGANIZATION. THESE FACTORS COMBINED WITH STEEP MIDLEVEL LAPSE
RATES OF 7.5-8 C/KM PER OBJECTIVE ANALYSES WILL FAVOR A CONTINUED
POTENTIAL FOR ADDITIONAL STRONGER STORMS TO PRODUCE PRIMARILY A HAIL
THREAT.
SINCE 0840Z...REGIONAL RADAR IMAGERY INDICATED AN INCREASE IN TSTM
DEVELOPMENT FROM CENTRAL MCCLAIN COUNTY OK TO CENTRAL AND ERN KIOWA
COUNTY OK. THESE STORMS APPEAR TO BE FORMING ALONG A COLD FRONT
ADVANCING SWD INTO CENTRAL AND SWRN OK WHERE THE INFLOW OF MODERATE
INSTABILITY IS SUPPORTING THIS NEW DEVELOPMENT.
..PETERS.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...OUN...
LAT...LON 34109762 34319816 34829893 35009855 35159766 35369712
35369628 35869562 35769372 35299379 34669450 34539455
34119526 34049714 34109762
000
ACUS11 KWNS 210921
SWOMCD
SPC MCD 210920
ARZ000-OKZ000-211015-
MESOSCALE DISCUSSION 0745
NWS STORM PREDICTION CENTER NORMAN OK
0420 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PART OF SRN/ERN OK INTO WEST CENTRAL AR
CONCERNING...SEVERE THUNDERSTORM WATCH 199...
VALID 210920Z - 211015Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 199
CONTINUES.
SUMMARY...AN ISOLATED HAIL THREAT CONTINUES ACROSS WW 199 INTO THE
EARLY MORNING...AS NEW STORMS DEVELOP FROM KIOWA COUNTY OK THROUGH
CENTRAL MCCLAIN/SRN CLEVELAND COUNTIES TO MCINTOSH COUNTY OK.
DISCUSSION...A BROAD WAA ZONE EXTENDING INTO SRN OK WITHIN THE NOSE
OF A 45-50 KT SSWLY LLJ COMBINED WITH A NWD INFLUX OF MODERATE
INSTABILITY SUGGESTS TSTM DEVELOPMENT WILL CONTINUE FROM W-E ACROSS
WW 199. EFFECTIVE BULK SHEAR UP TO 50 KT SUPPORTS STORM
ORGANIZATION. THESE FACTORS COMBINED WITH STEEP MIDLEVEL LAPSE
RATES OF 7.5-8 C/KM PER OBJECTIVE ANALYSES WILL FAVOR A CONTINUED
POTENTIAL FOR ADDITIONAL STRONGER STORMS TO PRODUCE PRIMARILY A HAIL
THREAT.
SINCE 0840Z...REGIONAL RADAR IMAGERY INDICATED AN INCREASE IN TSTM
DEVELOPMENT FROM CENTRAL MCCLAIN COUNTY OK TO CENTRAL AND ERN KIOWA
COUNTY OK. THESE STORMS APPEAR TO BE FORMING ALONG A COLD FRONT
ADVANCING SWD INTO CENTRAL AND SWRN OK WHERE THE INFLOW OF MODERATE
INSTABILITY IS SUPPORTING THIS NEW DEVELOPMENT.
..PETERS.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...OUN...
LAT...LON 34109762 34319816 34829893 35009855 35159766 35369712
35369628 35869562 35769372 35299379 34669450 34539455
34119526 34049714 34109762
000
ACUS11 KWNS 210921
SWOMCD
SPC MCD 210920
ARZ000-OKZ000-211015-
MESOSCALE DISCUSSION 0745
NWS STORM PREDICTION CENTER NORMAN OK
0420 AM CDT TUE MAY 21 2013
AREAS AFFECTED...PART OF SRN/ERN OK INTO WEST CENTRAL AR
CONCERNING...SEVERE THUNDERSTORM WATCH 199...
VALID 210920Z - 211015Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 199
CONTINUES.
SUMMARY...AN ISOLATED HAIL THREAT CONTINUES ACROSS WW 199 INTO THE
EARLY MORNING...AS NEW STORMS DEVELOP FROM KIOWA COUNTY OK THROUGH
CENTRAL MCCLAIN/SRN CLEVELAND COUNTIES TO MCINTOSH COUNTY OK.
DISCUSSION...A BROAD WAA ZONE EXTENDING INTO SRN OK WITHIN THE NOSE
OF A 45-50 KT SSWLY LLJ COMBINED WITH A NWD INFLUX OF MODERATE
INSTABILITY SUGGESTS TSTM DEVELOPMENT WILL CONTINUE FROM W-E ACROSS
WW 199. EFFECTIVE BULK SHEAR UP TO 50 KT SUPPORTS STORM
ORGANIZATION. THESE FACTORS COMBINED WITH STEEP MIDLEVEL LAPSE
RATES OF 7.5-8 C/KM PER OBJECTIVE ANALYSES WILL FAVOR A CONTINUED
POTENTIAL FOR ADDITIONAL STRONGER STORMS TO PRODUCE PRIMARILY A HAIL
THREAT.
SINCE 0840Z...REGIONAL RADAR IMAGERY INDICATED AN INCREASE IN TSTM
DEVELOPMENT FROM CENTRAL MCCLAIN COUNTY OK TO CENTRAL AND ERN KIOWA
COUNTY OK. THESE STORMS APPEAR TO BE FORMING ALONG A COLD FRONT
ADVANCING SWD INTO CENTRAL AND SWRN OK WHERE THE INFLOW OF MODERATE
INSTABILITY IS SUPPORTING THIS NEW DEVELOPMENT.
..PETERS.. 05/21/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LZK...SHV...TSA...OUN...
LAT...LON 34109762 34319816 34829893 35009855 35159766 35369712
35369628 35869562 35769372 35299379 34669450 34539455
34119526 34049714 34109762
| 
