MESOSCALE DISCUSSION NWS STORM PREDICTION CENTER

[CaptinCrunch]

MESOSCALE DISCUSSION 1259
NWS STORM PREDICTION CENTER NORMAN OK
0132 PM CDT THU JUN 09 2005

AREAS AFFECTED...WRN KS THROUGH ERN OK PANHANDLE...NERN TX PANHANDLE
AND NWRN OK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 091832Z - 092100Z



WRN KS THROUGH THE OK AND TX PANHANDLES INTO NWRN OK ARE BEING
MONITORED FOR THUNDERSTORM INITIATION. THUNDERSTORMS ARE EXPECTED
DEVELOP IN PORTIONS OF THESE AREAS BY 21Z. SUPERCELLS WITH VERY
LARGE HAIL AND ISOLATED TORNADOES WILL BE THE PRIMARY THREATS. A
TORNADO WATCH WILL LIKELY BE NEEDED FOR THIS AREA BY 21Z.

THIS AFTERNOON A LARGE NEARLY STATIONARY OUTFLOW BOUNDARY EXTENDS
FROM CNTRL OK NWWD THROUGH NWRN OK THEN NWD INTO WRN KS. A SURFACE
LOW EXIST OVER SWRN KS WITH THE DRYLINE EXTENDING SWD FROM THE LOW
THROUGH THE TX PANHANDLE. A SLY LOW LEVEL JET WILL PERSIST THROUGH
WRN OK AND WRN KS AND IS ADVECTING RICHER MOISTURE NWD WHERE IT
SHOULD CONTINUE TO MIX THROUGH THE BOUNDARY LAYER AND CONTRIBUTE TO
RECOVERY THIS AFTERNOON. DEWPOINTS HAVE ALREADY RECOVERED INTO THE
MID 60S OVER MUCH OF WRN KS. STRONG SURFACE HEATING AND STEEP LAPSE
RATES WILL CONTRIBUTE TO FURTHER DESTABILIZATION WITH MLCAPE FROM
3000 TO 4000 J/KG IN VICINITY OF THE OUTFLOW BOUNDARY. THE 18Z RAOB
FROM AMA SHOWED LITTLE CAP REMAINING AS TEMPERATURES CLIMB INTO THE
UPPER 80S. THE DRYLINE SHOULD BEGIN TO MIX EWD AND MIGHT EVENTUALLY
MERGE WITH THE OUTFLOW BOUNDARY. STORMS ARE EXPECTED TO DEVELOP IN
VICINITY OF DRYLINE AND OR ALONG THE OUTFLOW BOUNDARY AS THE CAP
CONTINUES TO WEAKEN. SUPERCELLS WITH VERY LARGE HAIL WILL BE LIKELY.
THE TORNADO POTENTIAL WILL BE ENHANCED AS STORMS MOVE EWD AND OVER
THE OUTFLOW BOUNDARY WHERE BACKED SELY LOW LEVEL FLOW IS RESULTING
IN LARGER LOW LEVEL HODOGRAPHS.

[CaptinCrunch]

MESOSCALE DISCUSSION 1261
NWS STORM PREDICTION CENTER NORMAN OK
0243 PM CDT THU JUN 09 2005

AREAS AFFECTED...EXTREME SERN NM THROUGH W TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 091943Z - 092145Z



SERN NM THROUGH PARTS OF WRN TX ARE BEING MONITORED FOR THUNDERSTORM
INITIATION. IF STORMS DEVELOP...SUPERCELLS WITH VERY LARGE HAIL WILL
BE LIKELY. ISOLATED TORNADOES MAY ALSO BE POSSIBLE. IF TRENDS BEGIN
TO SUGGEST INITIATION IS IMMINENT...A WW WILL BE NEEDED FOR PORTIONS
OF THIS AREA.

DRYLINE EXTENDS FROM THE TX PANHANDLE JUST W OF AMARILLO SWWD INTO
EXTREME SERN NM THEN SWD TO JUST E OF FORT STOCKTON. THE ATMOSPHERE
HAS BECOME VERY UNSTABLE E OF THIS BOUNDARY. DEWPOINTS IN THE UPPER
60S UNDERNEATH STEEP LAPSE RATES IN CONJUNCTION WITH STRONG SURFACE
HEATING HAS CONTRIBUTED TO MLCAPE FROM 3500 TO 4000 J/KG. LATEST
VISIBLE IMAGERY SHOWS CUMULUS DEVELOPING IN VICINITY OF AND W OF THE
DRYLINE WHERE DEEP MIXING IS OCCURRING. ONCE STORMS DEVELOP...THEY
SHOULD MOVE EWD AND INTENSIFY AS THEY INTERCEPT THE STRONGER
INSTABILITY. THE 0-6 KM SHEAR ON THE ORDER OF 35 TO 40 KT AND
MODERATE WLY MID LEVEL FLOW WILL SUPPORT SUPERCELLS. THE LOW LEVEL
FLOW AND SHEAR ARE RELATIVELY WEAK...BUT GIVEN SHEAR THROUGH A
DEEPER LAYER SUPPORTIVE OF SUPERCELLS AND THE PRESENCE OF STRONG
INSTABILITY...POTENTIAL FOR ISOLATED TORNADOES MAY ALSO EXIST.

[CaptinCrunch]

MESOSCALE DISCUSSION 1263
NWS STORM PREDICTION CENTER NORMAN OK
0358 PM CDT THU JUN 09 2005

AREAS AFFECTED...NRN NEB...SCENTRAL/SERN SD...NWRN IA AND SWRN MN

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 092058Z - 092300Z



WE ARE MONITORING THE AREA FOR INCREASING TRENDS AND A POTENTIAL FOR
A WW BY 22Z.

INCREASING SWLY MID LEVEL FLOW WILL CONTINUE TO SUPPORT INCREASING
POTENTIAL FOR STORM ROTATION IN ELEVATED CONVECTION OVER NCENTRAL
NEB/SCENTRAL SD. MODERATE INSTABILITY WITH MUCAPES RISING TO AROUND
2000 J/KG COMBINED WITH DEEP LAYER SHEAR AROUND 35 KTS WILL SUPPORT
THE THREAT FOR AT LEAST ISOLATED LARGE HAIL WITH THE STRONGEST
STORMS AS THEY MOVE ENEWD INTO SCENTRAL SD.

FARTHER EAST...SUFFICIENT HEATING AND CONVERGENCE ALONG SLOWLY
RETREATING WARM FRONT/OUTFLOW BOUNDARY OVER NERN NEB/NWRN IA AND FAR
SERN SD ALONG WITH INCREASING LARGE SCALE ASCENT MAY SUPPORT SURFACE
BASED TSTM DEVELOPMENT OVER THE AREA IN THE NEXT FEW HOURS. STRONG
LOW LEVEL SHEAR /0-1 KM SHEAR AROUND 15 KTS/ IN THIS AREA AS EVIDENT
BY 20Z MRR PROFILER AND FSD VWP DATA SUGGESTS THE POTENTIAL FOR AN
ISOLATED TORNADO AS WELL AS LARGE HAIL/DAMAGING WINDS IF SURFACE
BASED STORMS CAN DEVELOP/INTENSIFY GIVEN MODERATE INSTABILITY WITH
MUCAPES AROUND 2000 J/KG.

[CaptinCrunch]

MESOSCALE DISCUSSION 1275
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT FRI JUN 10 2005

AREAS AFFECTED...SWRN TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 101258Z - 101430Z



TSTMS DEVELOPING ACROSS SWRN TX THIS MORNING MAY POSE A LARGE HAIL
THREAT.

TSTM INITIATION HAS OCCURRED A LITTLE EARLIER THAN EXPECTED THIS
MORNING ACROSS SWRN TX. WATER VAPOR IMAGERY SHOWS A SUBTLE LEAD
MID-LEVEL IMPULSE EJECTING EWD ACROSS SWRN TX AND MAY BE MODULATING
THE VERTICAL VELOCITY FIELDS. 12Z MAF SOUNDING SUGGESTS THAT THE
PARCELS ARE ELEVATED WITH BASES IN THE 800-650 MB LAYER. MAGNITUDE
OF H7-H5 LAPSE RATES SUGGESTS THAT THE PRIMARY SEVERE THREAT WILL BE
LARGE HAIL.

THE MAIN BELT OF ASCENT ASSOCIATED WITH THE AZ/NM UPPER LOW HAS YET
TO SPREAD EWD ONTO THE HIGH PLAINS. ADDITIONAL TSTMS WILL BE LIKELY
LATER IN THE MORNING...ESPECIALLY FARTHER N.

[CaptinCrunch]

MESOSCALE DISCUSSION 1327
NWS STORM PREDICTION CENTER NORMAN OK
1241 PM CDT MON JUN 13 2005

AREAS AFFECTED...SE MO...SRN AND ERN IL

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 131741Z - 131945Z



AS STORMS INITIATE AND DEVELOP ACROSS SE MO...ERN AND SRN IL...LARGE
HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE. THE THREAT MAY
EXPAND EWD INTO WRN KY AND FAR WRN IND BY LATE THIS AFTERNOON. A WW
MAY BECOME NECESSARY ACROSS THE REGION.

SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING NWD ACROSS SRN
AND ERN IL WHERE 70+ SFC DEWPOINTS EXIST. THIS IS CREATING MODERATE
INSTABILITY FROM SERN MO EXTENDING NWD INTO NERN IL. STORMS ARE
INITIATING ALONG THE INSTABILITY AXIS IN SE MO AND FROM ROCKFORD IL
EXTENDING SSEWD TO NEAR JOLIET. ACCORDING TO FORECAST SOUNDINGS FOR
ERN IL AND SE MO...THE CELLS ARE INITIATING IN A MODERATELY SHEARED
ENVIRONMENT WITH 0-6 KM SHEAR VALUES AROUND 35 KT. THIS SHOULD BE
SUFFICIENT FOR A SEVERE MULTICELL THREAT WITH A FEW SUPERCELLS
POSSIBLE IN THE STRONGER INSTABILITY ACROSS SRN IL AND SERN MO.
LARGE HAIL AND WIND DAMAGE WILL BE LIKELY WITH SUPERCELLS THAT
DEVELOP WITH HAIL AND MARGINAL WIND DAMAGE POSSIBLE WITH THE
STRONGER MULTICELL STORMS.

[CaptinCrunch]

MESOSCALE DISCUSSION 1328
NWS STORM PREDICTION CENTER NORMAN OK
0156 PM CDT MON JUN 13 2005

AREAS AFFECTED...ERN NEB/SRN MN/IA/NW MO

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 131856Z - 132030Z



...INCREASING SEVERE POTENTIAL ACROSS ERN NEB/WRN IA/SRN MN...

LATEST VISIBLE SATELLITE IMAGERY SUGGEST STRONG ASCENT IN PROGRESS
...GIVEN FIELD OF CLOUDINESS EAST OF THE NEB UPPER LOW.
HOWEVER...CLOUDS /MAINLY STRATOCUMULUS/ SHOW THAT WEAK CINH
INDICATED ON 18Z OMAHA SOUNDING IS STILL IN PLACE.
NEVERTHELESS...GIVEN THE STRENGTH OF THE WINDS ON BOTH THE OMAHA AND
TOPEKA SOUNDING /WHICH HAD 80 KT AT 500 MB/ AND THE FACT THAT BOTH
LOCATIONS HAVE LITTLE OR NO INHIBITION LEFT...SUGGEST THAT
CONVECTION MAY DEVELOP VERY QUICKLY. FORCING ASSOCIATED WITH UPPER
LOW GIVEN CURRENT CONFIGURATION WILL LIKELY BE MAINLY LINEAR CALLING
INTO QUESTION HOW MUCH OF A TORNADO THREAT THERE WILL BE. AS
YET...LOW LEVEL CONVERGENCE IS WEAK. AREA IS BEING MONITORED FOR
SIGNS OF DEEPER CONVECTIVE DEVELOPMENT.

[CaptinCrunch]

MESOSCALE DISCUSSION 1330
NWS STORM PREDICTION CENTER NORMAN OK
0234 PM CDT MON JUN 13 2005

AREAS AFFECTED...CNTRL/ERN OK/SE KS/SW INTO CNTRL MO

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 131934Z - 132130Z



...AREA BEING MONITORED FOR SEVERE POTENTIAL WITH AIRMASS HIGHLY
UNSTABLE AND STRONG SHEAR PRESENT...

COLD FRONT EXTENDS FROM CNTRL KS INTO NE OK...JUST NORTHWEST OF
TULSA AND THEN ALONG AND NEAR THE INTERSTATE 44 CORRIDOR. CUMULUS
ARE DEVELOPING ALONG THIS BOUNDARY...WITH MORE CONGESTUS TOWARD THE
NE CORNER OF OK AND EVEN SOME SFC BASED CBS NORTHEAST OF SPRINGFIELD
MO. AREA OVER MO IN PARTICULAR IS BEING AGITATED BY SUBTLE SRN
STREAM DISTURBANCE AND ASSOCIATED LARGE SCALE FORCING. 18Z SOUNDINGS
FROM SPRINGFIELD AND NORMAN SHOW LITTLE OR NO INHIBITION. SINCE THE
FRONT IS MOVING SLOWLY SE...AND THERE ARE SEVERAL OTHER CONFLUENCE
BOUNDARIES...INITIATION WILL NOT BE A PROBLEM GIVEN SUFFICIENT LOW
LEVEL CONVERGENCE.

THE MAIN SEVERE THREAT WILL BE LARGE HAIL/DAMAGING WINDS INITIALLY
AS STORMS WILL TEND TO FORM INTO DISCRETE SUPERCELLS. THERE WILL
ALSO BE A THREAT OF TORNADOES...GIVEN VARIOUS SFC BOUNDARIES/AT
LEAST 35 KT DEEP LAYER SHEAR/SFC DEWPOINTS IN THE 70S AND A VERY
UNSTABLE AIRMASS WITH MLCAPE VALUES RANGING FROM 3000-4000 J/KG.

..TAYLOR.. 06/13/2005

[CaptinCrunch]

MESOSCALE DISCUSSION 1332
NWS STORM PREDICTION CENTER NORMAN OK
0515 PM CDT MON JUN 13 2005

AREAS AFFECTED...E CNTRL MO INTO CNTRL IL

CONCERNING...SEVERE THUNDERSTORM WATCH 472...476...

VALID 132215Z - 140015Z



CONTINUE WWS. ADDITIONAL WW MAY BE NEEDED FROM THE CHICAGO AREAS
SOUTHWARD THROUGH THE REMAINDER OF NORTHEAST ILLINOIS...PERHAPS
PARTS OF WESTERN INDIANA...WITHIN THE NEXT COUPLE OF HOURS.

INTENSE CONVECTIVE DEVELOPMENT IS ONGOING NEAR/WEST THROUGH NORTH OF
THE ST. LOUIS AREA. THIS IS WHERE STEEPEST ISENTROPIC ASCENT...
ASSOCIATED WITH LOW-LEVEL WARM ADVECTION AND DIVERGENT UPPER FLOW
EAST OF MID MISSOURI VALLEY CLOSED LOW...IS FORCING MOIST PARCELS TO
LEVEL OF FREE CONVECTION. INHIBITION APPEARS STRONGER ALONG/SOUTH
OF INTERSTATE 44/64...WITH STRONGER FORCING LIKELY TO SHIFT ACROSS
THE ST. LOUIS MO/SPRINFIELD IL AREAS SHORTLY...INTO DECATUR/MATTOON/
CHAMPAIGN VICINITIES BY 01-03Z.

EVOLVING CONVECTIVE CLUSTER SHOULD FORM A SIGNIFICANT SURFACE COLD
POOL OVER THE NEXT FEW HOURS...WHICH LIKELY WILL MAINTAIN CONVECTIVE
DEVELOPMENT AS IT SURGES INTO MOIST/MOISTENING BOUNDARY LAYER OVER
CENTRAL ILLINOIS WITH CAPE IN EXCESS OF 2000 J/KG. LARGE HAIL
APPEARS LIKELY WITH STRONGER STORMS IN NEAR TERM...AND POTENTIAL FOR
BROADER SCALE DAMAGING WIND EVENT SEEMS LIKELY TO INCREASE
NORTHEAST OF ST. LOUIS INTO EAST CENTRAL ILLINOIS.

[CaptinCrunch]

MESOSCALE DISCUSSION 1347
NWS STORM PREDICTION CENTER NORMAN OK
0134 PM CDT TUE JUN 14 2005

AREAS AFFECTED...UPPER MI...ERN WI

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 141834Z - 142030Z



HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE WITH THE STRONGER
CELLS ACROSS ERN WI AND UPPER MI OVER THE NEXT FEW HOURS.

WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW AN UPPER-LOW
ACROSS ERN MN WITH STRONG LARGE-SCALE ASCENT MOVING NWD INTO UPPER
MI. THIS WILL SUPPORT CONTINUED DEVELOPMENT OF STORMS AS ASCENT
INCREASES FROM SOUTH TO NORTH ACROSS THE REGION. SFC TEMPS IN THE
70S F AND DEWPOINTS IN THE 50S F ARE RESULTING IN SBCAPE VALUES
ABOVE 1000 J/KG. THIS COMBINED WITH 20 TO 25 KT OF DEEP LAYER SHEAR
SHOULD BE SUFFICIENT FOR ISOLATED SEVERE STORMS. 500 MB TEMPS BELOW
-10C AND MARGINALLY STEEP LAPSE RATES SHOULD BE ENOUGH FOR HAIL WITH
THE STRONGER CELLS. A WIND DAMAGE THREAT MAY ALSO EXIST ESPECIALLY
ALONG THE LEADING EDGE OF BOWING LINE SEGMENTS.

[CaptinCrunch]

MESOSCALE DISCUSSION 1353
NWS STORM PREDICTION CENTER NORMAN OK
1113 AM CDT WED JUN 15 2005

AREAS AFFECTED...CNTRL AND SRN OK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 151613Z - 151815Z



A HAIL THREAT MAY PERSIST OVER THE NEXT 2 HOURS ACROSS CNTRL AND SRN
OK. HOWEVER...THE SEVERE THREAT IS EXPECTED TO REMAIN TOO ISOLATED
TO WARRANT A WW ATTM.

SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING SW TO NE ACROSS
SRN AND CNTRL OK WITH DEWPOINTS NEAR 70 F. SCATTERED ELEVATED STORMS
ARE ONGOING JUST UPSTREAM OF THE MOIST AXIS ALONG A BAND OF
LOW-LEVEL CONVERGENCE WHICH SHOULD HELP SUSTAIN THE STORMS OVER THE
NEXT FEW HOURS. FORECAST SOUNDINGS ACROSS SCNTRL OK BY MIDDAY SHOW
SBCAPE VALUES RISING TO AROUND 1000 J/KG...0-6 KM SHEAR VALUES
AROUND 20 KT AND MID-LEVEL LAPSE RATES NEAR 7.0 C/KM. THIS
COMBINATION OF PARAMETERS MAY BE SUFFICIENT FOR MARGINALLY SEVERE
MULTICELL STORMS WITH HAIL THE PRIMARY THREAT.

[CaptinCrunch]

MESOSCALE DISCUSSION 1360
NWS STORM PREDICTION CENTER NORMAN OK
0129 PM CDT THU JUN 16 2005

AREAS AFFECTED...ERN TX AND NRN/CNTRL LA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 161829Z - 162030Z



SCATTERED STRONG TO SEVERE STORMS WITH DOWNBURST AND HAIL POTENTIAL
WILL INCREASE ACROSS PARTS OF ERN TX AND CNTRL LA THROUGH THIS
AFTERNOON. CURRENTLY WEAK SHEAR ACROSS THE REGION IS EXPECTED TO
LIMIT STORM ORGANIZATION AND CELL DURATION. WHILE A WATCH DOES NOT
CURRENTLY APPEAR NECESSARY...AREA WILL CONTINUE TO BE MONITORED FOR
AN INCREASE IN SEVERE WEATHER POTENTIAL.

MOST INTENSE CELLS INITIATED EARLIER ALONG OUTFLOW BOUNDARY
INTERSECTION NW OF IER. ADDITIONAL UPDRAFTS CONTINUE TO DEVELOP NEAR
THE STALLING OUTFLOW BOUNDARIES FROM DE SOTO TO JACKSON PARISHES IN
NRN LA. AIRMASS SOUTH OF THIS CONVECTION HAS BECOME VERY UNSTABLE
AND WEAKLY CAPPED WITH LATEST OBJECTIVE DATA SUGGESTING MLCAPE IN
EXCESS OF 2000 J/KG. AT PRESENT...WEAK DEEP LAYER SHEAR WAS LIKELY
LIMITING STORM ORGANIZATION AND EXPECT MULTICELLULAR CONVECTION TO
POSE PRIMARILY AN ISOLATED DOWNBURST WIND THREAT. THERE IS SOME
CHANCE THAT STORMS COULD BECOME BETTER ORGANIZED AS BAND OF STRONGER
MID LEVEL FLOW...CURRENTLY OVER THE RED RIVER/NRN TX AREA...SPREADS
ESEWD OVER THE NEXT FEW HOURS. FURTHERMORE...IF ENOUGH CONVECTIVE
DEVELOPMENT OCCURS COINCIDENT WITH THIS INCREASE IN FLOW...A LARGER
COLD POOL COULD ALLOW UPSCALE DEVELOPMENT TO A MORE WIDESPREAD
DAMAGING WIND/HAIL SITUATION. IF IT BECOMES CLEARER THAT THIS
SCENARIO IS UNFOLDING...A SEVERE TSTM WATCH MAY BE NEEDED OVER PARTS
OF THE REGION.

[CaptinCrunch]

MESOSCALE DISCUSSION 1361
NWS STORM PREDICTION CENTER NORMAN OK
0143 PM CDT THU JUN 16 2005

AREAS AFFECTED...NRN WY AND MUCH OF SRN/CENTRAL/NERN MT

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 161843Z - 162045Z



INCREASING THREAT OF LARGE HAIL AND DAMAGING WINDS DURING NEXT FEW
HOURS ACROSS S-CENTRAL/CENTRAL MT. AN ISOLATED SEVERE THUNDERSTORM
THREAT WILL EXIST THIS AFTERNOON ACROSS NERN MT. WW WILL LIKELY BE
NEEDED SOON FOR PORTIONS OF S-CENTRAL/CENTRAL MT.

WV IMAGERY AT 1830Z CONTINUES TO SHOW STRONG UPPER-LEVEL JET PUSHING
EWD THROUGH THE GREAT BASIN. THIS IS LEADING TO LARGE-SCALE UPPER
DIVERGENCE ACROSS ERN ID/SWRN MT...AND NW-SE ARC OF SHOWERS AND
THUNDERSTORMS TRACKING ACROSS THE SWRN MTNS OF MT AT THE PRESENT
TIME. DESTABILIZATION WILL CONTINUE EAST OF THESE STORMS GIVEN AMPLE
SURFACE HEATING AND SURFACE DEWPOINTS IN THE LOW TO MID 50S ACROSS
CENTRAL/E-CENTRAL MT AND FAR NRN WY. A N-S SURFACE BOUNDARY ACROSS
PHILLIPS AND GARFIELD COUNTIES IS ASSOCIATED WITH A MOISTURE
DISCONTINUITY WITH SURFACE DEWPOINTS IN THE LOW 60S ALONG AND EWD TO
NEAR GGW. THE 18Z GGW SOUNDING INDICATES MUCAPE OF 2300 J/KG AND
SUFFICIENT DEEP-LAYER SHEAR FOR LONG-LIVED CELLS CONTAINING LARGE
HAIL. MORE ORGANIZED/WIDESPREAD SEVERE WEATHER THREAT IS EXPECTED TO
EVOLVE FROM ONGOING CONVECTIVE ACTIVITY FROM HLN TO COD AS IT
ENCOUNTERS GREATER MOISTURE/INSTABILITY TO THE EAST. GREATEST THREAT
APPEARS TO BE ACROSS S-CENTRAL MT WITH POTENTIAL FOR ISOLATED
SUPERCELLS AND BOWING SEGMENTS ORGANIZED ALONG CONVECTIVE OUTFLOW
BOUNDARIES.

[CaptinCrunch]

MESOSCALE DISCUSSION 1362
NWS STORM PREDICTION CENTER NORMAN OK
0254 PM CDT THU JUN 16 2005

AREAS AFFECTED...SERN CO...SWRN KS...WRN OK....TX/OK PNHDLS

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 161954Z - 162230Z



TSTM DEVELOPMENT IS EXPECTED ACROSS PARTS OF THE SRN HIGH PLAINS
WITHIN THE NEXT 1-3 HOURS. STORMS SHOULD QUICKLY BECOME SEVERE AND A
WATCH WILL PROBABLY BE ISSUED OVER PARTS OF THE REGION SHORTLY.

STRONG SURFACE HEATING COUPLED WITH REBOUNDING LOW LEVEL MOISTURE
HAS CONTRIBUTED TO A RAPID INCREASE IN INSTABILITY FROM SERN CO/NERN
NM ESEWD ACROSS THE PANHANDLES AND INTO PORTIONS OF SWRN KS AND NWRN
OK. WHILE MUCH OF THIS VERY UNSTABLE AIR MASS IS PROBABLY STILL
CAPPED BY WARM MID LEVEL TEMPERATURES /700MB TEMPS OF 12-14C/...A
NARROW AXIS OF STRONGER LOW LEVEL FORCING FOR ASCENT AND FOCUS FOR
MOISTURE EXISTS NEAR THE EDGE OF THE CAP ACROSS WRN/NWRN OK. THIS
AXIS IS ASSOCIATED WITH A DIFFUSE/RESIDUAL OUTFLOW BOUNDARY LEFT IN
THE WAKE OF LATE NIGHT/EARLY MORNING MCS AND EXTENDS NWWD TO
INTERSECT LEE/THERMAL TROUGH AXIS ACROSS SERN CO AND THE OK/TX
PNHDLS. ANOTHER HOUR OR SO OF HEATING SHOULD SUFFICIENTLY ERODE THE
CAP TO RESULT IN RAPID TSTM DEVELOPMENT NEAR THESE FEATURES.

FURTHER SUPPORT FOR DEVELOPMENT MAY COME FROM LOW-AMPLITUDE
MID/UPPER LEVEL IMPULSE TRANSLATING EAST ACROSS THE FOUR-CORNERS
AREA AT THIS TIME. BAND OF ANTICYCLONICALLY CURVED MID LEVEL FLOW OF
30-35KT ATOP WEAKER SSWLY LOW LEVEL FLOW WILL RESULT IN FAVORABLE
EFFECTIVE SHEAR FOR SUPERCELLS. SPC HAIL MODEL OUTPUT INDICATES THE
ENVIRONMENT MIGHT SUPPORT VERY LARGE HAIL IN EXCESS OF 3 INCHES.
TORNADO POTENTIAL APPEARS LIMITED BY WEAK LOW LEVEL FLOW/SHEAR...BUT
MAY BE ENHANCED FOR SUPERCELLS TRACKING EWD/SEWD ALONG RESIDUAL
BOUNDARY WHERE LFC IS LIKELY TO BE LOCALLY LOWER.

[CaptinCrunch]

MESOSCALE DISCUSSION 1363
NWS STORM PREDICTION CENTER NORMAN OK
0308 PM CDT THU JUN 16 2005

AREAS AFFECTED...S-CENTRAL/SERN NEB AND FAR NRN KS

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 162008Z - 162215Z



ISOLATED SEVERE THUNDERSTORMS POSSIBLE DURING THE REMAINDER OF THIS
AFTERNOON INTO THIS EVENING ACROSS S-CENTRAL/SERN NEB AND FAR NRN
KS. EXPECTED LIMITED COVERAGE OF SEVERE WILL LIKELY PRECLUDE WW
ISSUANCE.

WELL-DEFINED MESOSCALE CONVECTIVE VORTEX...WITH EYE-LIKE FEATURE ON
VISIBLE IMAGERY...WAS CENTERED OVER BLAINE COUNTY IN N-CENTRAL NEB
AT 1950Z. TRAILING SURFACE OUTFLOW BOUNDARY EXTENDS AROUND THE ERN
AND SRN PERIPHERY OF THE MCV...WITH POTENTIAL FOR REGENERATION OF
CONVECTIVE CELLS IN THE GRAND ISLAND AREA. OUTFLOW BOUNDARY EXTENDS
E-W ACROSS FAR SRN NEB...WHERE IT INTERSECTS NRN EDGE OF INSTABILITY
AXIS. THE 100MB MLCAPE VALUES HAVE INCREASED TO AROUND 2000 J/KG
NEAR THE NEB/KS BORDER. MODEST LOW-TO-MID LEVEL VEERING ON HASTINGS
VAD WIND PROFILE SUGGESTS LOW-LEVEL ASCENT DUE TO WARM ADVECTION
ACROSS THE STALLED OUTFLOW BOUNDARY...LIKELY SUFFICIENT FOR
REDEVELOPMENT OF DEEP CONVECTION. SUFFICIENT SFC-6KM SHEAR /AROUND
35KT/ AND INSTABILITY EXIST FOR A LOCALIZED THREAT OF STRONG TO
ISOLATED SEVERE STORMS ACROSS THE DISCUSSION AREA THROUGH THE
REMAINDER OF THE DAYLIGHT HOURS. STEEP MID-LEVEL LAPSE RATES SUGGEST
A LARGE HAIL THREAT WITH STRONGER CELLS. TRAINING EWD CELL MOTIONS
OF ONLY AROUND 10 KT MAY ALSO RESULT IN LOCALIZED HEAVY RAINFALL IN
S-CENTRAL NEB DURING THE NEXT FEW HOURS.

[CaptinCrunch]

MESOSCALE DISCUSSION 1364
NWS STORM PREDICTION CENTER NORMAN OK
0449 PM CDT THU JUN 16 2005

AREAS AFFECTED...ERN NM INTO WRN TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 162149Z - 162315Z



DEVELOPING TSTMS WILL BE CAPABLE OF ISOLATED DAMAGING WINDS AND/OR
LARGE HAIL. WW IS NOT ANTICIPATED UNLESS ACTIVITY CAN ORGANIZE A
COLD POOL.

AS OF 2138Z...REGIONAL RADAR IMAGERY SHOWED TSTMS DEVELOPING FROM
QUAY/DE BACA SWD INTO EDDY COUNTIES IN ERN NM EWD INTO BAILEY AND
COCHRAN COUNTIES IN WRN TX. HERE...TEMPERATURES IN THE LOWER TO MID
90S COUPLED WITH DEWPOINTS IN THE 50S HAVE CONTRIBUTED TO A
DEEPLY-MIXED BOUNDARY LAYER AND MODERATE INSTABILITY WITH MLCAPES OF
1000-1500 J/KG. CURRENT LBB VWP AND JAYTON PROFILER INDICATE SLY
LOW-LEVEL WINDS VEERING TO NWLY ABOVE 4-5 KM AGL WHICH IS RESULTING
IN 30-40 KTS OF DEEP-LAYER SHEAR. GIVEN THIS ENVIRONMENT...POTENTIAL
WILL EXIST FOR HIGH-BASED TSTMS /INCLUDING POSSIBLY SUPERCELLS/
CAPABLE OF ISOLATED LARGE HAIL AND DAMAGING WINDS. A WW IS NOT
ANTICIPATED ATTM...HOWEVER SHOULD STORMS MERGE INTO CLUSTERS AND
ORGANIZE A COLD POOL...SEVERE POTENTIAL MAY BECOME MORE
WIDESPREAD...POSSIBLY REQUIRING THE ISSUANCE OF A WW.

[Guest]

MESOSCALE DISCUSSION 1366
NWS STORM PREDICTION CENTER NORMAN OK
0621 PM CDT THU JUN 16 2005

AREAS AFFECTED...FAR SERN NEB AND NERN KS

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 162321Z - 170115Z

POTENTIAL EXISTS FOR ISOLATED SEVERE THUNDERSTORMS ACROSS FAR SERN
NEB AND NERN KS THROUGH LATE THIS EVENING. LARGE HAIL WILL LIKELY BE
THE PRIMARY THREAT. OVERALL EXTENT OF SEVERE THREAT IS EXPECTED TO
BE LIMITED. HOWEVER...TRENDS WILL BE MONITORED FOR POSSIBLE WW.

AT 23Z...MESOSCALE CONVECTIVE VORTEX CONTINUES TO MOVE SLOWLY ESEWD
ACROSS E-CENTRAL NEB PER LATEST VISIBLE IMAGERY. ASSOCIATED REMNANT
OUTFLOW BOUNDARY EXTENDING ALONG THE ERN THROUGH SRN PERIPHERY OF
THE MCV HAS BEEN ASSOCIATED WITH A GRADUAL INCREASE IN NEW
CONVECTIVE CELLS NEAR THE KS/NEB BORDER JUST NORTH OF CNK. SURFACE
BASED INSTABILITY AXIS...WITH 100MB MLCAPE VALUES OF 2500-3000
J/KG...INTERSECTS THE EAST-WEST PORTION OF THE OUTFLOW BOUNDARY IN
THIS AREA. LIMITED CONVECTIVE INHIBITION SHOULD ALLOW FOR
CONTINUATION OF STRONG TO ISOLATED SEVERE CONVECTION ALONG THE
OUTFLOW BOUNDARY DURING THE NEXT 2-3 HOURS. PROFILERS INDICATE THAT
SFC-3KM WINDS ARE LIGHT...WITH 30-40KT MID-LEVEL FLOW ACROSS NRN
KS/SRN NEB. CONDITIONS SHOULD BE SUFFICIENT FOR A FEW LONG-LIVED
CORES CONTAINING LARGE HAIL...WITH CELLS MOVING SLOWLY ESEWD AT
5-10KT WITH MOTION OF MCV AND ASSOCIATED SFC BOUNDARY.

..BANACOS.. 06/16/2005


ATTN...WFO...EAX...OAX...TOP...ICT...GID...

39599866 40039859 40479694 40439643 40299575 39419516
39039534 38789566 38619629 38579712 38669771 38899829
39169850



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[TexasStooge]

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   MESOSCALE DISCUSSION 1374
   NWS STORM PREDICTION CENTER NORMAN OK
   0126 PM CDT FRI JUN 17 2005
   
   AREAS AFFECTED...CENTRAL AND WRN MT
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 171826Z - 171930Z
   
   SEVERE STORMS WITH LARGE HAIL...DAMAGING WINDS AND ISOLATED
   TORNADOES WILL DEVELOP THROUGH THE AFTERNOON. A WW WILL BE REQUIRED.
   
   
   CONTINUED HEATING AHEAD OF COLD FRONT ALONG WITH BROAD AREA OF
   55-60+ SURFACE DEWPOINTS IN PLACE WILL ALLOW FOR MDT INSTABILITY TO
   DEVELOP AHEAD OF COLD FRONT. GIVEN DEGREE OF FORCING AND STRONG DEEP
   LAYER SHEAR PROFILES IN PLACE...STORM MOTIONS WILL BE QUITE FAST
   WITH DAMAGING WIND GUSTS AND LARGE HAIL LIKELY. ISOLATED TORNADOES
   CANNOT BE RULED OUT...WITH HIGHEST POTENTIAL WITHIN SURFACE MOIST
   AXIS WHERE SURFACE WINDS ARE BACKED AND LCL HEIGHTS LOWEST.
   
   ..JEWELL.. 06/17/2005
   
   
   ATTN...WFO...BYZ...GGW...RIW...TFX...MSO...
   
   48960855 46890846 45100943 45031200 45721230 46351248
   48931338

[TexasStooge]

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   MESOSCALE DISCUSSION 1375
   NWS STORM PREDICTION CENTER NORMAN OK
   0137 PM CDT FRI JUN 17 2005
   
   AREAS AFFECTED...FL
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 171837Z - 172030Z
   
   CONVECTION DEVELOPING ACROSS CNTRL AND SRN FL WILL HAVE A MARGINAL
   WIND DAMAGE THREAT THIS AFTERNOON. THE ACTIVITY IS EXPECTED TO
   REMAIN TOO ISOLATED TO WARRANT A WW ATTM.
   
   WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD UPPER-TROUGH OVER THE
   SERN US WITH A MOISTURE PLUME DRIFTING EWD ACROSS THE FL PENINSULA.
   STORMS HAVE DEVELOPED IN THE MOIST PLUME PARTIALLY DUE TO SFC
   HEATING AND LOW-LEVEL CONVERGENCE. FORECAST SOUNDINGS THIS AFTERNOON
   IN FL SHOW ABOUT 20 KT OF 0-6 KM SHEAR. THIS MAY BE ENOUGH FOR A FEW
   SEVERE STORMS...HOWEVER THE STORMS SHOULD BE PULSE IN NATURE DUE TO
   THE RELATIVELY WEAK SHEAR. MODERATE INSTABILITY IS ALREADY IN PLACE
   DUE TO WARMING SFC TEMPS. THIS COMBINED WITH SFC DEWPOINTS IN THE
   LOWER 70S AND STEEP LOW-LEVEL LAPSE RATES MAY BE ENOUGH FOR A
   ISOLATED MARGINAL WIND THREAT ACROSS THE SRN TWO-THIRDS OF FL THIS
   AFTERNOON.
   
   ..BROYLES.. 06/17/2005
   
   
   ATTN...WFO...MFL...MLB...TBW...
   
   25128057 26968223 28388240 28718149 28348069 26668008

[TexasStooge]

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   MESOSCALE DISCUSSION 1381
   NWS STORM PREDICTION CENTER NORMAN OK
   1125 AM CDT SAT JUN 18 2005
   
   AREAS AFFECTED...ERN GA...SC
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 181625Z - 181830Z
   
   SCATTERED STORMS WILL CONTINUE TO INITIATE AND EXPAND IN COVERAGE
   ACROSS ERN GA AND SC. THE STRONGER CELLS WILL HAVE A POTENTIAL FOR
   LARGE HAIL AND/OR WIND DAMAGE.
   
   WATER VAPOR IMAGERY CURRENTLY SHOWS A HIGH-AMPLITUDE UPPER-TROUGH
   OVER THE ERN US WITH SEVERAL SHORTWAVE TROUGHS ROTATING AROUND THE
   SRN EDGE. AS A RESULT...STRONG LARGE-SCALE ASCENT WILL SPREAD ACROSS
   THE REGION TODAY AIDING THE DEVELOPMENT OF SCATTERED STORMS.
   OBJECTIVE ANALYSIS CURRENTLY SHOWS AN AXIS OF HIGH INSTABILITY WITH
   SBCAPE VALUES AROUND 3000 J/KG ACROSS ERN GA AND SRN SC. THE CAPPING
   INVERSION IS NEARLY GONE AND A FEW SFC-BASED STORMS ARE INITIATING
   IN ERN GA. AS THE CELLS CONTINUE TO INCREASE IN INTENSITY...MODERATE
   DEEP LAYER SHEAR ACROSS THE REGION SUGGESTS AN ISOLATED SUPERCELL
   THREAT WILL EXIST. FORECAST SOUNDINGS FOR THIS AFTERNOON ACROSS THE
   REGION SHOW LAPSE RATES AROUND 7.5 C/KM AND 500 MB TEMPS OF -11C TO
   -13C. THE STEEP LAPSE RATES AND COLD AIR ALOFT WILL LIKELY ENHANCE
   THE THREAT FOR LARGE HAIL AND ISOLATED WIND DAMAGE AS CELLS MATURE
   THIS AFTERNOON.
   
   ..BROYLES.. 06/18/2005
   
   
   ATTN...WFO...ILM...CHS...CAE...JAX...FFC...TAE...
   
   31108259 31918309 33378219 34078093 33917986 33057933
   31958090 30788164

[CaptinCrunch]

MESOSCALE DISCUSSION 1399
NWS STORM PREDICTION CENTER NORMAN OK
0739 AM CDT MON JUN 20 2005

AREAS AFFECTED...SERN ND / W CENTRAL MN / NERN SD

CONCERNING...SEVERE THUNDERSTORM WATCH 503...

VALID 201239Z - 201415Z



STRONG / SEVERE STORMS CONTINUE ACROSS PARTS OF WW.

WELL-DEVELOPED BOW ECHO CONTINUES MOVING ENEWD ACROSS SERN ND AT 45
KT...WHILE ADDITIONAL STRONG STORMS -- INCLUDING A SPLIT SUPERCELL
PAIR -- ARE DEVELOPING JUST AHEAD OF THE BOWING MCS. EXPECT SEVERE
THREAT TO PERSIST FOR THE NEXT SEVERAL HOURS ACROSS THIS REGION.

EXTRAPOLATION SUGGESTS THAT NRN PORTIONS OF BOW MAY AFFECT COUNTIES
JUST N OF WW -- ACROSS E CENTRAL ND AND NWRN MN -- IN THE NEXT 1 1/2
TO 2 HOURS OR SO. HOWEVER...AXIS OF GREATEST INSTABILITY REMAINS
WELL WITHIN WW...THUS EXPECT THAT A SLIGHTLY MORE EWD MOVEMENT OF
BOW MAY EVOLVE WITH TIME -- KEEPING MAIN SEVERE THREAT WITHIN WW.
EITHER WAY...ANY THREAT N OF WW WOULD LIKELY BE LIMITED TO ONLY A
TIER OR TWO OF COUNTIES...AND THUS NEW WW DOES NOT APPEAR LIKELY
ATTM. SHOULD THREAT INCREASE MORE SUBSTANTIALLY N OF WW WITH
TIME...A REPLACEMENT WW COULD BECOME MORE LIKELY.