SPC MCD 261747
SDZ000-NEZ000-COZ000-262000-
SPC MESOSCALE DISCUSSION 1809 FOR SWRN SD/WRN NEB/NE CO
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
CONVECTIVE TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT
AND POSSIBILITY OF WW...WHICH MAY BE NEEDED WITHIN NEXT HOUR OR SO.
STRONG DAYTIME HEATING IS CONTRIBUTING TO RAPID DESTABILIZATION
NEAR HIGH PLAINS SURFACE TROUGH...FROM SOUTHWESTERN SOUTH DAKOTA
INTO NORTHEAST COLORADO. ALTHOUGH MORNING RAOBS SUGGEST LOWER/MID
90S SURFACE TEMPERATURES WILL NEED TO BE REACHED BEFORE ONSET OF
SURFACE-BASED CONVECTIVE DEVELOPMENT...LATEST WATER VAPOR IMAGERY
INDICATES CAPPING MAY BE WEAKENING AS MID-LEVEL TROUGH SHIFTS EAST
OF THE ROCKIES INTO THE HIGH PLAINS. INTENSE SURFACE OR NEAR
SURFACE-BASED CONVECTIVE DEVELOPMENT ALREADY APPEARS UNDERWAY
ACROSS BENNETT COUNTY SOUTH DAKOTA...WITH ADDITIONAL ACTIVITY
LIKELY ACROSS THE BLACK HILLS SHORTLY. CONVECTION IS EXPECTED TO
CONTINUE DEVELOPING SOUTH/SOUTHWESTWARD ALONG LEE SURFACE TROUGH
INTO WESTERN NEBRASKA...AND POSSIBLY NORTHEAST COLORADO...WITHIN
THE NEXT 2 TO 3 HOURS.
VERY STEEP MID-LEVEL LAPSE RATES WITH MEAN MIXED LAYER CAPE IN
EXCESS OF 2000 J/KG WILL PROVIDE FAVORABLE THERMODYNAMIC
ENVIRONMENT FOR SEVERE STORMS WITH LARGE HAIL. DAMAGING WINDS WILL
ALSO BE POSSIBLE...PARTICULARLY AS LARGE CONVECTIVE CLUSTER EVOLVES
LATER THIS AFTERNOON...BENEATH DIFLUENT/DIVERGENT UPPER FLOW REGIME
...DOWNSTREAM OF LARGE-SCALE TOUGH OVER THE GREAT BASIN.
..KERR.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 261809
SPC MCD 261809
ALZ000-GAZ000-SCZ000-TNZ000-NCZ000-262100-
SPC MESOSCALE DISCUSSION 1810 FOR NERN/ECENTRAL AL...NRN/CENTRAL GA
...FAR SWRN NC/SERN TN AND WRN SC
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
ISOLATED THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WET
MICROBURSTS/MARGINALLY SEVERE HAIL WILL BE POSSIBLE OVER THE AREA
THROUGH THE AFTERNOON. MARGINAL NATURE AND EXPECTED LACK OF
ORGANIZED CONVECTION SHOULD PRECLUDE THE NEED FOR A WW.
RECENT WV IMAGERY SHOWS A DISTINCT UPPER LEVEL JET MAX OVER MS/WRN
AL...ROTATING AROUND BASE OF OHIO VALLEY UPPER LOW. 26/17Z SURFACE
MESOANALYSIS INDICATED THAT A SURFACE LOW AROUND 1011 MB CENTERED
NEAR ATL CONTINUES TO DEEPEN...LIKELY IN RESPONSE TO ENHANCED UPPER
DIVERGENCE WITH APPROACHING JET MAX. SURFACE TEMPERATURES HAVE
WARMED INTO THE UPPER 80S OVER PORTIONS OF CENTRAL GA...WITH LOWER
TO MID 80S ELSEWHERE. COMBINED WITH DEWPOINTS IN THE UPPER
60S/LOWER 70S...MODERATE INSTABILITY HAS DEVELOPED WITH AROUND 2500
J/KG OF MUCAPE. REGIONAL MORNING SOUNDINGS INDICATED SUFFICIENTLY
STEEP LOW TO MID LEVEL LAPSE RATES AND MID LEVEL DRY AIR TO SUPPORT
DAMAGING DOWNBURST WINDS. MARGINALLY SEVERE HAIL WILL ALSO BE
POSSIBLE ACROSS NERN AL/NRN GA...WHERE ENVIRONMENT WILL BE
CHARACTERIZED BY SLIGHTLY COOLER MID LEVEL TEMPS/LOWER WBZ HEIGHTS.
AS ADDITIONAL HEATING AND ENHANCED CONVERGENCE CONTINUES THROUGH
MID AFTERNOON NEAR THE LOW CENTER AND ALONG DISTINCT CONVERGENCE
AXES EXTENDING WNWWD AND EWD FROM THE LOW...CONTINUED DEVELOPMENT
/INTENSIFICATION OF THUNDERSTORMS WILL OCCUR FROM ERN AL ENEWD INTO
SERN TN/WRN SC. THE GREATEST POTENTIAL FOR ISOLATED SEVERE APPEARS
TO BE OVER NERN AL/NRN GA...SERN TN/SWRN NC AND WRN SC WHERE
STRONGEST UPPER LEVEL DIVERGENCE AND MODEST DEEP LAYER SHEAR
/AROUND 25 KTS/ WILL BE COINCIDENT WITH STRONGEST UPPER LEVEL
DIVERGENCE AND ENHANCED LOW LVL CONVERGENCE ALONG INTERSECTION OF
OUTFLOW BOUNDARY AND CONVERGENCE TROUGH.
..CROSBIE.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 261930
SPC MCD 261930
NDZ000-262200-
SPC MESOSCALE DISCUSSION 1811 FOR CNTRL ND
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
CONVECTIVE TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT
AND POSSIBILITY OF A WW.
LATEST OBJECTIVE GUIDANCE SUGGESTS THAT DAYTIME HEATING IS
CONTRIBUTING TO POTENTIALLY MODERATE INSTABILITY ACROSS MUCH OF
CENTRAL/EASTERN NORTH DAKOTA. SUBSTANTIAL MID-LEVEL CONVECTIVE
INHIBITION STILL APPEARS TO BE PRESENT...AND STRONGER MID/UPPER
FORCING FOR UPWARD VERTICAL MOTION HAS SHIFTED NORTHWARD INTO PARTS
OF SOUTHERN SASKATCHEWAN/MANITOBA. HOWEVER...IN WAKE OF SHORT WAVE
TROUGH PIVOTING NORTHWARD OUT OF NORTHERN NORTH DAKOTA...LOW-LEVEL
WARM ADVECTION REGIME PERSISTS...IN ADVANCE OF LARGE-SCALE GREAT
BASIN TROUGH. THIS SUPPORTS POTENTIAL FOR INCREASING CONVECTIVE
DEVELOPMENT WITHIN THE NEXT FEW HOURS...PARTICULARLY ACROSS PARTS
OF CENTRAL NORTH DAKOTA...NORTH/EAST OF BISMARCK...WHERE SURFACE
CONVERGENCE APPEARS STRONGEST. LATEST VISIBLE IMAGERY/RADAR TRENDS
INDICATE DEEPENING CONVECTIVE DEVELOPMENT IS ALREADY UNDERWAY
ACROSS THIS AREA...WHERE VERTICAL SHEAR PROFILES MAY BE SUFFICIENT
FOR SUPERCELLS...ON SOUTHERN PERIPHERY OF 30 KT WESTERLY MID-LEVEL
JET.
..KERR.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 262010
SPC MCD 262010
SDZ000-NEZ000-COZ000-KSZ000-262200-
SPC MESOSCALE DISCUSSION 1812 FOR WRN NEB/NE CO
CONCERNING...SEVERE THUNDERSTORM WATCH 637...638...
INSTABILITY AXIS EXTENDS FROM WESTERN CHERRY COUNTY NEB CELL
SOUTHWARD INTO NORTHEAST COLORADO...EAST OF AKRON. THIS IS ON
THERMAL GRADIENT EAST OF LOW-LEVEL THERMAL RIDGE/SURFACE TROUGH
AXIS...WHERE MID-LEVEL LAPSE RATES ARE STEEPEST...AND CONTRIBUTING
TO SURFACE-BASED CAPE IN EXCESS OF 2000 J/KG. ACTIVITY NEXT COUPLE
OF HOURS WILL CONTINUE TO DEVELOP SOUTHWARD ALONG THIS AXIS ACROSS
WESTERN NEBRASKA...WHILE SOUTHWEST NEBRASKA CONVECTIVE CLUSTER
PERSISTS...DEVELOPS NORTHWARD. MERGER OF TWO CONVECTIVE SYSTEMS
APPEARS POSSIBLE SOUTHEAST OF ALLIANCE BY THE 26/23Z-27/00Z TIME
FRAME...WHERE EVOLUTION OF LARGER CONVECTIVE SYSTEM WILL CONTINUE
INTO THE EVENING HOURS...ALONG/WEST OF SOUTHERLY LOW-LEVEL JET AXIS
...WHICH WILL INCREASE TO AROUND 40 KT EARLY THIS EVENING.
LOW-LEVEL CONVERGENCE WILL REMAIN FOCUSED NEAR INTERSECTION OF
CONVECTIVELY ENHANCED BOUNDARY AND LEE SURFACE TROUGH...NORTH/
NORTHWEST OF GOODLAND KANSAS INTO THE EVENING HOURS. THIS WILL
HELP MAINTAIN QUASI-STATIONARY CLUSTER OF THUNDERSTORMS BENEATH
INCREASINGLY DIFLUENT/DIVERGENT UPPER FLOW REGIME...AND EXCESSIVE
RAIN TOTALS WILL BECOME INCREASING THREAT.
..KERR.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 262018
SPC MCD 262018
KSZ000-262230-
SPC MESOSCALE DISCUSSION 1813 FOR PORTIONS OF NERN/ECENTRAL KS
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
WE WILL CONTINUE TO MONITOR CONVECTIVE TRENDS FOR A POSSIBLE WW...
SHOULD FURTHER INTENSIFICATION OCCUR.
CLUSTER OF THUNDERSTORMS THAT WERE OVER SCENTRAL/CENTRAL NEB
EARLIER HAVE GENERATED A WELL DEFINED OUTFLOW BOUNDARY WHICH WILL
CONTINUE TO MOVE SSEWD ACROSS NERN/NCENTRAL KS OVER THE NEXT FEW
HOURS. 2-3 MB/2 HRLY PRESSURE RISES ARE EVIDENT BEHIND THIS
BOUNDARY AND SHOULD MAINTAIN SUFFICIENTLY STRONG CONVERGENCE FOR
ADDITIONAL CONVECTIVE INITIATION/INTENSIFICATION AS CONVECTIVE
INHIBITION REMAINS MINIMAL SOUTH OF THE BOUNDARY. THE MODIFIED 12Z
TOP SOUNDING FOR RECENT OBSERVATIONS TO THE SOUTH OF THE CONVECTION
INDICATED MODERATE INSTABILITY WITH 1500-2000 J/KG OF MUCAPE. IF
CONVECTION CAN CONTINUE TO INTENSIFY AND ORGANIZE ALONG THIS
OUTFLOW BOUNDARY...25 TO 30 KT 3-6 KM WINDS ALONG WITH SUFFICIENT
DRY AIR AT MID LEVELS NOTED WOULD SUPPORT COLD POOL DEVELOPMENT AND
AN INCREASED THREAT FOR DAMAGING DOWNBURST WINDS.
..CROSBIE.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 262224
SPC MCD 262224
OKZ000-TXZ000-270000-
SPC MESOSCALE DISCUSSION 1814 FOR TX AND OK PANHANDLE
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
SEVERE THUNDERSTORM WATCH MAY BE REQUIRED FOR PORTIONS OF THE TX/OK
PANHANDLE.
HIGH BASED THUNDERSTORMS ARE BEGINNING TO DEVELOP OVER THE CENTRAL
TX PANHANDLE WHERE SFC TEMPERATURES HAVE WARMED INTO THE UPPER 90S-
100 DEG F. LATEST DATA SUGGESTS SFC BOUNDARY WITH RICHER BOUNDARY
LAYER MOISTURE EXISTS JUST A FEW COUNTIES EAST OF THIS ACTIVITY.
WITH LLJ EXPECTED TO INCREASE OVER THE NEXT FEW HOURS...SUSTAINED
LOW LEVEL CONVERGENCE WILL UNDOUBTEDLY ENHANCE ONGOING CONVECTION.
ALTHOUGH THUNDERSTORMS WILL DEVELOP EWD INTO PORTIONS OF THE ERN
PANHANDLE...STORM PROPAGATION WILL DRIVE ORGANIZING CLUSTERS
SWD...ESPECIALLY AS COLD POOL DEEPENS. LARGE HAIL AND GUSTY WINDS
ARE THE PRIMARY SEVERE THREATS.
..DARROW.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 262304
SPC MCD 262304
NDZ000-270200-
SPC MESOSCALE DISCUSSION 1815 FOR ND
CONCERNING...SEVERE THUNDERSTORM WATCH #639...
MULTICELLULAR TSTM COMPLEX CONTINUES HEADING SLOWLY NWD THRU NCNTRL
ND WITH SOME ADDITIONAL DEVELOPMENT IN THE MIDST OF OUTFLOW
BOUNDARY IN WRN ND. WW WILL LIKELY REMAIN IN EFFECT THRU EXPIRATION
TIME OF 27/02Z.
WV/VIS IMAGERY DEPICTS MID-LVL CYCLONE CENTER IN SRN SASKATCHEWAN
WITH SUBTLE STATIONARY BOUNDARY EXTENDING FROM NCNTRL MN WWD INTO
ECNTRL ND. A MODERATELY UNSTABLE AIRMASS IS A RESULT OF
TEMPERATURES INTO THE MID-UPPER 80S WITH DEWPOINTS FROM THE MID
50S-MID 60S...YIELDING 100MB CAPES FROM 1500-2000 J/KG. WEAK
SHORTWAVE ENERGY EJECTING EWD AMIDST CYCLONIC REGIME WILL COMBINE
WITH STRONG UPPER LEVEL DIFLUENCE....SOME ADDITIONAL SFC HEATING
...AND OUTFLOW INTERACTION TO CONTINUE TO YIELD SCATTERED SEVERE
TSTMS INTO THE EARLY-MID EVENING HOURS.
..NADEN.. 08/26/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270033
SPC MCD 270033
COZ000-KSZ000-NEZ000-270200-
SPC MESOSCALE DISCUSSION 1816 FOR ERN CO...WRN KS...SWRN NEB
CONCERNING...SEVERE THUNDERSTORM WATCH 640...
DEVELOPING SW-NE MCS OVER CENTRAL PORTIONS OF WW IS BEGINNING TO
SURGE SWD AT ROUGHLY 30 KT. ALTHOUGH THIS ACTIVITY IS DEVELOPING
LEWP STRUCTURE...ISOLATED SUPERCELLS ARE EMBEDDED WITH HP
CHARACTERISTICS. INTENSIFYING LLJ INTO THIS ACTIVITY SUGGESTS
FORWARD PROPAGATION WILL INCREASE AND DAMAGING WIND THREAT REMAINS
A REAL POSSIBILITY...IN ADDITION TO LARGE HAIL.
..DARROW.. 08/27/02
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270150
SPC MCD 270150
NEZ000-SDZ000-270400-
SPC MESOSCALE DISCUSSION 1817 FOR WRN NEB
CONCERNING...SEVERE THUNDERSTORM WATCH #641...
SCATTERED TSTM ACTIVITY CONTINUES TO WEAKEN AND MOVE SWD IN WW#641.
IF PRESENT TRENDS CONTINUE OVER THE NEXT HOUR AND A HALF...WW WILL
LIKELY BE CANCELLED BY 27/03Z.
RECENT CELL MERGER HAS AIDED CELL INTENSIFICATION IN CHEYENNE
COUNTY JUST NORTH OF SIDNEY. THE REMAINDER OF THE ASSOCIATED
COMPLEX HAS WEAKENED CONSIDERABLY THE PAST HOUR EXCEPT FOR ACTIVITY
IN SERN GARDEN COUNTY. DESPITE COOLING CLOUD TOPS VIA IR IMAGERY
AND ESELY LOW-LVL INFLOW INTO COMPLEX VIA RECENT GLD VAD
PROFILE...STORMS IN WW #641 ARE EXPECTED TO CONTINUE TO WEAKEN OVER
THE NEXT HOUR OR SO AS THEY PROGRESS SSEWD INTO COLD POOL REMNANT
FROM WRN KS CONVECTIVE COMPLEX. PARTS OF NERN CO MIGHT EXPERIENCE
SOME STRONG WINDS AS COMPLEX MOVES SWD INTO LOGAN COUNTY IN THE
NEXT HOUR...BUT OVERALL SEVERE THREAT IS DIMINISHING.
..NADEN.. 08/27/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270152
SPC MCD 270152
COZ000-KSZ000-NEZ000-270300-
SPC MESOSCALE DISCUSSION 1818 FOR WRN KS...ERN CO...SWRN NEB
CONCERNING...SEVERE THUNDERSTORM WATCH 640...
SEVERE THUNDERSTORM WATCH MAY BE REQUIRED DOWNSTREAM FOR PORTIONS
OF OK/TX PANHANDLES AND NWRN OK BY 03Z.
WELL DEFINED MVC HAS DEVELOPED WITHIN CONVECTIVE COMPLEX OVER GOVE
COUNTY KS. PRECIPITATION SHIELD CONTINUES TO EXPAND AS LEADING
EDGE OF STRONGEST SURGE MOVES SWD AT ROUGHLY 35 KT ACROSS SWRN KS.
STRONG LOW LEVEL WARM ADVECTION WILL ENHANCE LARGE SCALE ASCENT AND
PROVIDE FAVORABLE INFLOW AS THIS MCS MOVES SEWD TOWARD THE OK
PANHANDLE. LEADING EDGE OF THIS ACTIVITY SHOULD EXIT WW SHORTLY
AFTER 03Z.
..DARROW.. 08/27/02
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270617
SPC MCD 270617
OKZ000-TXZ000-270800-
SPC MESOSCALE DISCUSSION 1819 FOR ERN TX PANHANDLE THROUGH WRN AND
W CNTRL OK
CONCERNING...SEVERE THUNDERSTORM WATCH 642...
WW 642 WILL BE REPLACED SHORTLY BY ANOTHER WW THAT WILL EXTEND
FARTHER E TO INCLUDE WRN AND CNTRL OK. THREAT FOR DAMAGING WIND AND
LARGE HAIL EXPECTED TO PERSIST NEXT 2-3 HOURS AS STORMS CONTINUE
SEWD THROUGH WRN AND CNTRL OK. STRONG SSWLY LOW LEVEL JET FROM
UNSTABLE WARM SECTOR EXPECTED TO PROVIDE SUFFICIENT INFLOW FOR
STORMS TO CONTINUE DEVELOPING SEWD THROUGH WRN AND CNTRL OK.
..DIAL.. 08/27/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270652
SPC MCD 270652
NDZ000-MNZ000-270900-
SPC MESOSCALE DISCUSSION 1820 FOR NERN ND AND NWRN MN
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...
THREAT FOR PRIMARILY HAIL IS EXPECTED TO PERSIST NEXT 2-3 HOURS
OVER NERN ND...POSSIBLY SPREADING INTO EXTREME NWRN MN. HOWEVER...
DUE TO THE EXPECTED VERY ISOLATED NATURE OF ANY HAIL EVENTS...A WW
IS NOT ANTICIPATED.
LATEST VWP DATA SHOW VEERING PROFILES THROUGH 2 KM OVER ERN ND.
THIS SUGGESTS LIFTING ASSOCIATED WITH WEAK WARM ADVECTION...
POSSIBLY ENHANCED BY A SUBTLE OUTFLOW BOUNDARY FROM EARLIER
STORMS...IS SUPPORTING CURRENT ELEVATED ACTIVITY. THOUGH VERTICAL
SHEAR IS RATHER WEAK...STORMS ARE DEVELOPING IN STEEP LAPSE RATE
ENVIRONMENT WITH COOL AIR ALOFT AND MODERATE MUCAPE.
..DIAL.. 08/27/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270758
SPC MCD 270758
OKZ000-TXZ000-271000-
SPC MESOSCALE DISCUSSION 1821 FOR CNTRL/SWRN OK THROUGH NW AND N
CNTRL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 643...
THREAT FOR PRIMARILY DAMAGING WIND AND SOME HAIL EXPECTED TO
PERSIST NEXT COUPLE HOURS WITH SEVERE MCS MOVING THROUGH SWRN AND
S CNTRL OK. BASED ON CURRENT STORM MOTION...ACTIVITY WILL BEGIN TO
MOVE INTO NWRN AND N CNTRL TX AFTER 10Z AND ANOTHER WW MAY BE
NEEDED FOR THIS AREA BY 09Z.
STRONG SSWLY LOW LEVEL JET FROM MODERATELY UNSTABLE WARM SECTOR
OVER NWRN TX IS PROVIDING FAVORABLE STORM RELATIVE INFLOW FOR
STORMS TO CONTINUE DEVELOPING SSEWD. MOREOVER...THE OK MCS HAS
DEVELOPED A STRONG COLD POOL WITH STRONG REAR INFLOW JET. THIS IN
CONJUNCTION WITH THE STRONG SSWLY LOW LEVEL JET IS SUPPORTING
STRONG CONVERGENCE ALONG THE LEADING GUST FRONT. WWD DEVELOPMENT
APPEARS TO BE LIMITED BY STRONGER CAP SO THREAT FOR SEVERE MCS IS
HIGHEST IN A RELATIVELY NARROW CORRIDOR ALONG INSTABILITY GRADIENT
FROM ERN PARTS OF NW TX INTO THE WRN PARTS OF N CNTRL TX. DAMAGING
WIND GUSTS APPEAR TO BE MAIN THREAT...BUT SOME HAIL MAY ALSO
ACCOMPANY THE STRONGER CORES.
..DIAL.. 08/27/02
...PLEASE SEE WWW.SPC.NOAA.GOV/ FOR GRAPHIC PRODUCT...
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 270921
SPC MCD 270921
OKZ000-TXZ000-271100-
SPC MESOSCALE DISCUSSION 1822 FOR S CNTRL/SWRN OK THROUGH NRN TX
CONCERNING...SEVERE THUNDERSTORM WATCH 643...644...
THREAT FOR WIDESPREAD DAMAGING WIND GUSTS EXPECTED TO CONTINUE OVER
S CNTRL OK DURING THE NEXT COUPLE OF HOURS AND THROUGH NRN TX
DURING THE FEW HOURS.
LATEST SURFACE ANALYSIS SHOWS MESOLOW HAS DEVELOPED ON NRN END OF
THE LINE OVER MCCLAIN COUNTY IN S CNTRL OK. WIND THREAT IS GREATEST
SW OF THE MESO-LOW FROM S CNTRL THROUGH SWRN OK WHERE STRONG REAR
INFLOW JET AND STRONG PRESSURE RISES BEHIND THE LEADING GUST FRONT.
THIS ACTIVITY IS BEGINNING TO SPREAD INTO PARTS OF NW TX.
WIDESPREAD DAMAGING WIND WITH NUMEROUS REPORTS OF DOWNED TREES AND
POWER OUTAGES HAVE BEEN REPORTED WITH THIS ACTIVITY IN OK INCLUDING
THE NORMAN AREA WHERE GUSTS APPROACHES 80 MPH.
..DIAL.. 08/27/02
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ZCZC SPCSWOMCD ALL
ACUS11 KWNS 271122
SPC MCD 271122
TXZ000-271300-
SPC MESOSCALE DISCUSSION 1823 FOR N CNTRL TX
CONCERNING...SEVERE THUNDERSTORM WATCH 644...
THREAT FOR PRIMARILY DAMAGING WIND EXPECTED TO PERSIST NEXT FEW
HOURS OVER N CNTRL TX AS LINE OF SEVERE STORMS CONTINUES SSEWD.
ACTIVITY WILL MOVE INTO THE DALLAS/FORT WORTH METRO AREA AROUND
12Z.
LINE OF STORMS WITH A HISTORY OF STRONG-DAMAGING WIND GUSTS EXTENDS
FROM STEPHENS COUNTY IN N CNTRL TX NEWD INTO EXTREME S CNTRL OK.
ACTIVITY IS MOVING SSEWD AT 35 TO 40 KT. SOME WWD DEVELOPMENT INTO
PARTS OF NWRN TX HAS BEEN OBSERVED RECENTLY. HOWEVER...RADAR DATA
SHOW THAT WRN PART OF THE LINE CONTINUES TO STRUGGLE DUE TO
STRONGER CAP. FARTHER E FROM N CNTRL TX INTO EXTREME SRN OK...MCS
REMAINS WELL ORGANIZED WITH STRONG REAR INFLOW JET AND SSWLY LOW
LEVEL JET MAINTAINING FAVORABLE INFLOW/CONVERGENCE ALONG LEADING
GUST FRONT. THERE IS SOME CONCERN THAT THE ERN PARTS OF THE LINE
MAY CONTINUE ON A MORE SEWD COURSE ALONG THE INSTABILITY GRADIENT
FROM NEAR DFW SEWD TO NEAR LFK. IF THIS TRENDS CONTINUES AND IT
APPEARS THE LINE WILL REMAIN SEVERE FOR SEVERAL MORE HOURS...
ANOTHER WW MIGHT WOULD BE NEEDED E/SE OF WW 644.
..DIAL.. 08/27/02
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