IWIN products will be migrated to newer systems soon. Please see additional information here       

 
FXUS64 KTSA 081948
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
248 PM CDT THU MAY 8 2003

DRYLINE POSITION CURRENTLY RUNNING NEAR A ALVA OK - ALTUS OK LINE 
WITH EXTENSIVE CLOUD COVER OVER EASTERN OK KEEPING T/TD SPREADS AOB 
10 DEGREES.  SURFACE LOW OVER WESTERN KANSAS WILL CONTINUE EASTWARD 
WITH DEFINED WARM FRONTAL BOUNDARY ALONG THE NE/KS BORER.  18Z OKC 
SOUNDING SAMPLED EXPLOSIVE THERMODYNAMIC PROFILE WITH VISIBLE 
IMAGERY INDICATING CU FIELD DEVELOPING NEAR DRYLINE BOUNDARY. 

LATEST RUC DATA SUPPORTS POTENTIAL FOR STRONG TORNADOES ACROSS NORTH 
CENTRAL/NORTHEAST OK LATE THIS AFTERNOON INTO EARLY EVENING.  DEEP 
LAYER SHEAR INCREASES TO 50-60KTS BY LATE AFTERNOON WITH 0-1KM SHEAR 
VECTOR MAGNITUDE OF 15-20KTS DURING THE SAME TIME FRAME.  
INSTABILITY WILL BE MORE THAN SUFFICIENT TO SUPPORT STRONGLY SHEARED 
ENVIRONMENT AND LOW LCL HEIGHTS WILL PROMOTE BENEFICIAL RFD 
GENERATION.

UNCERTAINTY REGARDING THE NUMBER OF DISCRETE SUPERCELLS AND LACK OF 
DEFINED SURFACE BOUNDARY TO LOCALLY BACK SURFACE WINDS ARE THE 
CURRENT LIMITING FACTORS FOR SIGNIFICANT TORNADO OUTBREAK.          

FORECAST ID = 07

.TSA...
AR...NONE.
OK...NONE.
















 
 
FXUS64 KOUN 081920
AFDOKC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
219 PM CDT THU MAY 8 2003

...POTENTIAL FOR A SIGNIFICANT SEVERE WEATHER OUTBREAK INCLUDING 
SUPERCELLS AND TORNADOES ACROSS THE CENTRAL THIRD OF OKLAHOMA DURING 
THE NEXT 3-9 HOURS...

MID/UPPER LEVEL TROF AND SFC LOW CONT TO RAPIDLY DEEPEN OVER WRN 
KS/ERN CO EARLY THIS AFTERNOON.. AND THERE IS SUBTLE EVIDENCE OF A 
SECONDARY IMPULSE PUSHING EWD ACROSS NEW MEXICO. 18Z OUN SOUNDING 
INDICATES THAT CAPPING IS MUCH WEAKER THAN PREVIOUSLY EXPECTED ALONG 
DRYLINE ACROSS MOST OF OKLAHOMA.  POTENT THERMODYNAMIC PROFILE IS 
EVIDENT WITH VERY HIGH BOUNDARY LAYER MOISTURE CONTENT.. LOW LCL 
HGHTS AND STEEP MID LEVEL LAPSE RATES. IN ADDITION..THE HODOGRAPH 
SHOWS SIGNIFICANT LOW LEVEL AND DEEP LAYER SHEAR IN PLACE.. HILITED 
BY A DISTINCT KINK IN THE HODOGRAPH AT ABOUT 1.5 KM AGL. THIS TYPE 
OF LOW LEVEL SHEAR PROFILE IN COMBINATION WITH ABOVE MENTIONED 
THERMODYNAMICS HAS OFTEN BEEN ASSOCIATED WITH ENVIRONMENTS 
SUPPORTIVE OF LONG LIVED STRONG/VIOLENT TORNADOES.  EXPECT 
INITIATION INVOF THE DRYLINE WITHIN THE NEXT COUPLE HOURS WITH 
SUPERCELL DEVELOPMENT LIKELY.  SVR THREAT WILL LIKELY CONTINUE WELL 
INTO THE NITE AS STRONG UVVS CONT ALONG DRYLINE UNTIL AT LEAST 06Z 
ACROSS MUCH OF OKLAHOMA.  LIKELY TO SEE DEVELOPMENT SWD INTO TEXAS 
LATER THIS AFT/EVE.

INSTABILITY AXIS WILL RELOAD FRIDAY OVER THE SE ZONES.. AND THEN 
EXPAND NWWD INTO REDEVELOPING WARM FRONTAL ZONE FRIDAY NITE.  HAVE 
READJUSTED POPS TO ACCOUNT FOR THIS THINKING.  NEXT WAVE WILL EJECT 
ONTO THE PLAINS SATURDAY.. BUT MAIN FOCUS FOR ACTIVITY WITH THIS 
WAVE LOOKS TO BE NORTHEAST OF THE OUN CWA ATTM. HOWEVER..STILL 
LIKELY TO SEE AT LEAST A FEW STORMS ALONG/SE OF I44 CORRIDOR AHEAD 
OF DRYLINE/FRONT.  IT APPEARS THAT LOW LEVEL RIDGING WILL FINALLY 
BUILD SWD FAR ENUF SUNDAY INTO MONDAY TO ALLOW FOR A BRIEF RESPITE 
FROM STORMS..BUT TROPICAL BOUNDARY LAYER AIR WILL BE LURKING CLOSE 
BY AND SHUD MOVE BACK NWD MONDAY/TUES AS LONG WAVE TROF RELOADS OVER 
THE WRN CONUS.  WE WILL BRING SLGT CHC POPS BACK INTO THE SW ZONES 
MONDAY AFTERNOON WITH ONSET OF MOISTURE RETURN.. AND THEN 
EXPAND/INCREASE POPS ACROSS THE REST OF THE AREA THRU MID WEEK.  
MORE BOUTS OF SVR STORMS SEEM LIKELY AS SIGNIFICANT INSTABILITY AXIS 
REMAINS SUPERIMPOSED UNDERNEATH STRONG MID LEVEL FLOW.
 MILLER

OKC   64  89  67  84 /  60  20  20  30
HBR   59  91  64  88 /  10  20  20  20
SPS   66  94  68  92 /  50  30  20  30
GAG   51  89  57  82 /  10  30  30  10
PNC   64  85  67  82 /  60  20  40  20
DUA   71  88  72  88 /  60  20  20  40

.OUN...
OK...NONE.
TX...NONE.




 
 
FXUS64 KTSA 081813
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
100 PM CDT THU MAY 8 2003

ENHANCED CU FIELD STARTING TO DEVELOP OVER WESTERN OKLAHOMA...  
AHEAD OF DRY LINE. AIRMASS HAD BECOME VERY UNSTABLE WITH MUCAPES IN 
EXCESS OF 4000 J/KG...COUPLED WITH 40-50 KT DEEP LAYER SHEAR OVER 
NORTHWEST OKLAHOMA.  THUNDERSTORMS ARE EXPECTED TO RAPIDLY DEVELOP 
BY MID AFTERNOON ALONG DRY LINE WITH PERSISTENT SUPERCELL 
THUNDERSTORMS LIKELY MOVING INTO EASTERN OKLAHOMA BETWEEN 4 AND 6 
PM. ALTHOUGH MAIN TORNADO THREAT APPEARS TO BE FOCUSED NORTH OF AREA 
OVER EASTERN KANSAS...ANY STORMS THAT DEVIATE TO THE RIGHT OF THE 
LOW LEVEL FLOW WILL LIKELY HAVE AN ENHANCED TORNADO THREAT.  IN 
ADDITION...HAIL UP TO THE SIZE OF BASEBALLS AND DAMAGING DOWNBURST 
WINDS TO 70 MPH WILL BE POSSIBLE WITH ANY SUPERCELLS.         

FORECAST ID = 12

.TSA...
AR...NONE.
OK...NONE.














 
 
FXUS64 KTSA 081549
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
1045 AM CDT THU MAY 8 2003

CURRENT FORECAST THIS AFTERNOON IS ON TRACK WITH NO CHANGES 
ANTICIPATED.  WILL UPDATE ONLY TO BUMP 2ND PERIOD POPS UP 
SLIGHTLY TO MATCH THIS AFTERNOONS POP CONFIGURATION.  IT APPEARS 
THAT THUNDERSTORM INITIATION WILL OCCUR LATE THIS AFTERNOON ALONG 
DRY LINE WITH PRECIP COVERAGE AT LEAST THE SAME OR GREATER AFTER 00Z 
ACROSS CWA.

STILL EXPECT ISOLATED SUPERCELL DEVELOPMENT WITH THE THREAT FOR 
BASEBALL HAIL...WIND GUSTS TO 70 MPH AND A FEW TORNADOES.  BEST 
CHANCE FOR TSTM DEVELOPMENT REMAINS OVER FAR NORTHEAST 
OKLAHOMA/NORTHWEST ARKANSAS...WHERE BETTER UPPER DYNAMICS/STRONGER 
CONVERGENCE WILL OCCUR ALONG THE DRY LINE.   WILL DISCUSS SEVERE 
THREAT POTENTIAL FURTHER ON THE 100 PM HWO UPDATE.  

FORECAST ID = 12

.TSA...
AR...NONE.
OK...NONE.












 
 
FXUS64 KOUN 081537
AFDOKC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1035 AM CDT THU MAY 8 2003

IN GENERAL... THINGS ARE GOING AS PLANNED.  WE MAY NEED TO MAKE SOME 
ADJUSTMENTS TO WIND SPEEDS FOR THIS AFTERNOON IF MODEL FORECASTS 
TURN OUT TO BE CORRECT.  THIS IS MAINLY A CONCERN IN NORTHWEST 
OKLAHOMA... WHERE SPEEDS MAY TURN OUT TO BE STRONGER THAN CURRENTLY 
FORECAST.  SO FAR... PROFILERS SUGGEST THAT SPEEDS WILL NOT GET 
QUITE THAT STRONG.  SIMILARLY... IN THAT SAME AREA TEMPERATURES ARE 
RUNNING A LITTLE WARMER THAN THE GOING FORECAST.  HOWEVER... 
SOMEWHAT COOLER AIR UPSTREAM SHOULD BRING THE ACTUAL READINGS AND 
THE FORECAST BACK TOGETHER WITHIN AN HOUR OR TWO.

WILL WATCH TRENDS AND MAKE ADJUSTMENTS AS NEEDED.

FCSTID = 23 = CMS
--------------------------------------------------------------------
435 AM CDT THU MAY 8 2003

BUSY NIGHT HERE WITH PERSISTENT TORNADIC SUPERCELL MOVING ACROSS 
SOUTHERN ZONES THIS MORNING.  PRODUCTS WILL LIKELY BE DELAYED... BUT 
SHOULD BE OUT BY AROUND 445 AM.

AS UPPER WAVE TRACKS NORTHEAST INTO CENTRAL PLAINS... THE SURFACE 
LOW WILL BE DRAGGED NORTHEAST AND PULL DRYLINE EAST.  THE WARM FRONT 
IS CURRENTLY OVER NORTHERN OKLAHOMA AND CONVECTION IS NOT WIDESPREAD 
ENOUGH TO HALT ITS ADVANCE.  ETA MODEL FORECAST SOUNDINGS SHOW AN 
UNCAPPED ATMOSPHERE DEVELOPING EVEN BY 18Z AHEAD OF THE DRYLINE SO 
EXPECT THUNDERSTORMS TO REDEVELOP THIS AFTERNOON. THERE MAY BE A 
BREAK IN THE ACTION ON THE BACKSIDE OF THE WAVE AFTER THIS EVENING. 
DO NOT THINK DRYLINE WILL ADVANCE QUITE AS FAR AS MODELS ADVERTISE 
TOMORROW WITHOUT A STRONG UPPER SYSTEM MOVING THROUGH... SO WILL 
KEEP MOISTURE AND HIGHER POPS FARTHER WEST.  WILL KEEP CHANCE OF 
THUNDER THROUGH MOST AREAS THROUGH SATURDAY UNTIL THE MAIN UPPER 
WAVE MOVES THROUGH THE AREA SATURDAY NIGHT.  THEN WE MAY FINALLY SEE 
A BRIEF BREAK IN THE THUNDERSTORM CHANCES.

FCSTID =   26
OKC   88  62  87  67 /  30  20  20  30
HBR   89  57  89  64 /  20  20  10  20
SPS   93  64  92  66 /  20  20  20  20
GAG   86  51  86  57 /  10  10  10  10
PNC   85  61  85  66 /  40  30  20  30
DUA   89  72  88  72 /  40  30  20  30

.OUN...
OK...NONE.
TX...NONE.




 
 
FXUS64 KTSA 081216
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
715 AM CDT THU MAY 8 2003

...HAZARDOUS WEATHER OUTLOOK DISCUSSION...

TORNADO WATCH HAS BEEN ISSUED FOR PORTIONS OF EAST CENTRAL OKLAHOMA 
AND WEST CENTRAL ARKANSAS UNTIL 9 AM CDT. SUPERCELL OVER LEFLORE 
COUNTY WILL CONTINUE INTO SOUTHERN SEBASTIAN OVER NEXT HOUR. SEVERE 
THREAT HAS ENDED FOR THE TIME BEING ACROSS THE REST OF THE AREA.

STAGE IS SET FOR ANOTHER ROUND OF SEVERE THIS AFTERNOON...BEST 
OPPORTUNITY WILL BE OVER NORTHEAST OKLAHOMA. WARM FRONT HAS BECOME 
RATHER ILL DEFINED BUT LOOKS TO BE SOMEWHERE AROUND TULSA AREA. 
PLENTY OF LOW LEVEL MOISTURE TO WORK WITH AS SFC DEW POINTS IN LOW 
TO MID 70S THROUGH ALMOST ALL OF CWA. DRY LINE IS PROGGED TO BE INTO 
CENTRAL OKLAHOMA AND THIS TIME SHOULD REMAIN A LITTLE FARTHER 
WEST...PROBABLY NOT CLEARING THE TULSA METRO. CLOUD COVER IN WAKE OF 
MORNING CONVECTION SHOULD DISSIPATE FAIRLY QUICK...SO SFC TEMPS 
SHOULD HAVE NO TROUBLE WARMING WELL INTO 80S BY AFTERNOON. MID LEVEL 
TEMPS DO CONTINUE TO WARM THROUGH THE DAY HOWEVER AND THIS WILL 
PROVIDE A STRONG CAP FOR MUCH OF THE DAY...ESPECIALLY OVER SE OK. 
FORECAST INSTABILITY PARAMETERS NOT AS EXTREME AS WHAT WE SAW 
TUESDAY...BUT CERTAINLY GOOD ENOUGH FOR STRONG UPDRAFTS WITH SFC 
BASED CAPES UP TO 4000 J/KG ROUGHLY NORTH OF TULSA. SHEAR PROFILES 
APPEAR VERY FAVORABLE FOR CELL ROTATION THIS AFTERNOON WITH 45-50KTS 
LLJ CONTINUING AT 850 MB.

CAP SHOULD BE BROKEN FAIRLY EASILY OVER NE OK BY CONVERGENCE ALONG 
DRY LINE BY APPROX 21Z...BUT STILL UNCERTAIN AS TO WHETHER THIS WILL 
OCCUR FARTHER SOUTH. DUE MAINLY TO THIS UNCERTAINTY HAVE PLACED 
HIGHEST RISK FOR SVR OVER NORTHEASTERN COUNTIES...BUT ANY STORMS 
THAT COULD GET GOING TO THE SOUTH WOULD LIKELY BE SEVERE AS WELL. 
LONG TRACK SUPERCELLS CERTAINLY POSSIBLE DUE TO THE FAVORABLE 
SHEAR...WITH VERY LARGE HAIL AND TORNADOES POSSIBLE.

FORECAST ID = 14

.TSA...
AR...NONE.
OK...NONE.

SULLIVAN








 
 
FXUS64 KTSA 081050
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
550 AM CDT THU MAY 8 2003

SUPERCELL STORM PREVIOUSLY IN PITTSBURG COUNTY LOST ITS ORGANIZATION 
AS THE MESOCYCLONE SEPARATED FROM THE THUNDERSTORM.  THE ORPHANED 
MESO IS TRACKING NORTHEAST THROUGH EASTERN PITTSBURG COUNTY AS OFF 
545 AM...WHILE THE THUNDERSTORM IS MOVING MORE EAST THROUGH LATIMER 
COUNTY.

LATIMER COUNTY CELL MAY BE TRYING REORGANIZE SOME...WITH A BROAD 
ROTATION.  WE WILL CONTINUE TO MONITOR IT FOR ROTATION POTENTIAL.

FORECAST ID = 08

.TSA...
AR...NONE.
OK...NONE.








 
 
FXUS64 KTSA 080953
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
453 AM CDT THU MAY 8 2003

SUPERCELL OVER PITTSBURG COUNTY REMAINS WELL ORGANIZED.  LOCAL STORM 
SPECIFIC S-R HELICITY ANALYSIS DEPICTS VALUES INCREASING FROM THE 
MID 200S INTO THE MID 300S AS THE CELL MOVES INTO LATIMER COUNTY.  
THIS WILL CONTINUE TO PROMOTE STORM ROTATION.

OTHER STRONG CELLS MOVING INTO MCINTOSH COUNTY ARE IN A RELATIVE S-R 
HELICITY MIN...BUT VALUES THERE ARE IN THE MID 200S.

WE ARE NOT IN CONTACT WITH ANY SPOTTERS OR OFFICIALS IN PITTSBURG 
COUNTY...SO NO GROUND TRUTH AT THIS TIME.  AT THE VERY LEAST HAIL TO 
PERHAPS BASEBALL SIZE MAY HAVE OCCURRED NORTH OF THE MESO TRACK.

FORECAST ID = 08

.TSA...
AR...NONE.
OK...NONE.







 
 
FXUS64 KOUN 080935
AFDOKC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
435 AM CDT THU MAY 8 2003

BUSY NIGHT HERE WITH PERSISTENT TORNADIC SUPERCELL MOVING ACROSS 
SOUTHERN ZONES THIS MORNING.  PRODUCTS WILL LIKELY BE DELAYED... BUT 
SHOULD BE OUT BY AROUND 445 AM.

AS UPPER WAVE TRACKS NORTHEAST INTO CENTRAL PLAINS... THE SURFACE 
LOW WILL BE DRAGGED NORTHEAST AND PULL DRYLINE EAST.  THE WARM FRONT 
IS CURRENTLY OVER NORTHERN OKLAHOMA AND CONVECTION IS NOT WIDESPREAD 
ENOUGH TO HALT ITS ADVANCE.  ETA MODEL FORECAST SOUNDINGS SHOW AN 
UNCAPPED ATMOSPHERE DEVELOPING EVEN BY 18Z AHEAD OF THE DRYLINE SO 
EXPECT THUNDERSTORMS TO REDEVELOP THIS AFTERNOON. THERE MAY BE A 
BREAK IN THE ACTION ON THE BACKSIDE OF THE WAVE AFTER THIS EVENING. 
DO NOT THINK DRYLINE WILL ADVANCE QUITE AS FAR AS MODELS ADVERTISE 
TOMORROW WITHOUT A STRONG UPPER SYSTEM MOVING THROUGH... SO WILL 
KEEP MOISTURE AND HIGHER POPS FARTHER WEST.  WILL KEEP CHANCE OF 
THUNDER THROUGH MOST AREAS THROUGH SATURDAY UNTIL THE MAIN UPPER 
WAVE MOVES THROUGH THE AREA SATURDAY NIGHT.  THEN WE MAY FINALLY SEE 
A BRIEF BREAK IN THE THUNDERSTORM CHANCES.

FCSTID =   26
OKC   88  62  87  67 /  30  20  20  30
HBR   89  57  89  64 /  20  20  10  20
SPS   93  64  92  66 /  20  20  20  20
GAG   86  51  86  57 /  10  10  10  10
PNC   85  61  85  66 /  40  30  20  30
DUA   89  72  88  72 /  40  30  20  30

.OUN...
OK...NONE.
TX...NONE.







 
 
FXUS64 KTSA 080920
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
420 AM CDT THU MAY 8 2003

THUNDERSTORM OVER PITTSBURG COUNTY IS BECOMING INCREASINGLY 
ORGANIZED AND IS EVOLVING INTO A SUPERCELL.

SHEAR AND INSTABILITY PARAMETERS FAVOR SUPERCELLS AND THIS CELL MAY 
BEGIN TO PRODUCT VERY LARGE HAIL AND HAS AN INCREASING TORNADO 
THREAT.

LATEST SCANS SHOW A STRONG MESO DEVELOPING IN THE CELL AND A TORNADO 
WARNING WILL BE ISSUED.

THE LONG-LIVED SUPERCELL FURTHER SOUTH HAS CONTINUED TO SHOW A SLOW 
DECREASE...SEE THE PREVIOUS DISCUSSION FOR MORE ON THIS STORM.

FORECAST ID = 08

.TSA...
AR...NONE.
OK...NONE.






 
 
FXUS64 KTSA 080853
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
352 AM CDT THU MAY 8 2003

THE LONG-LIVED TORNADIC SUPERCELL TRACKING DOWN THE RED RIVER VALLEY 
IS IS NOW MOVING A LITTLE NORTH OF DUE EAST...260 DEGREES AT 21 
KNOTS.  THIS IS A SLIGHT LEFT DEVIATION FROM THE PAST FEW HOURS.  
THIS REDUCES THE CELL SPECIFIC STORM-RELATIVE HELICITY FROM THE LOW 
300S AHEAD IN PUSHMATAHA AND CHOCTAW COUNTIES TO THE MID 200S.  IN 
ADDITION...SOME VEERING IN THE LOW-LEVEL FLOW IS POSSIBLE IN THE 
NEXT HOUR OR TWO AS THE SURFACE WARM FRONT TRIES TO MOVE/REFORM TO 
THE NORTH.

THE OVERALL TREND WITH THE CELL HAS BEEN A SLIGHT DROP IN THE 
OVERALL MASS OF REFLECTIVITY...BUT TO OTHERWISE MAINTAIN AN 
IMPRESSIVE SUPERCELL STRUCTURE.

GIVEN THAT THE OVERALL TRENDS WITH THE CELL AND ITS ENVIRONMENT ARE 
SLIGHTLY NEGATIVE SOME DECREASE IN CELL ORGANIZATION MAY OCCUR AS IT 
ENTERS OUR COUNTY WARNING AREA...BUT THE SITUATION IS FAR FROM CLEAR 
AND THE CELL WILL BE MONITORED CLOSELY.  EXTRAPOLATION OF THE 
MESOCYCLONE BRINGS IT INTO SOUTHWEST PUSMATAH COUNTY...VERY NEAR THE 
CHOCTAW COUNTY BORDER AT 1040Z.

FORECAST ID = 08

.TSA...
AR...NONE.
OK...NONE.




 
 
FXUS64 KTSA 080833
AFDTUL

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
325 AM CDT THU MAY 8 2003

AND THE SEVERE WEATHER CONTINUES...

ONGOING ELEVATED CONVECTION ALONG AND E OF 40-50 KT LOW-LEVEL JET 
WILL SPREAD N AND E OF THE FORECAST AREA BY MID-MORNING. SFC WARM 
FRONT ANALYZED OVER SRN OK WILL LIFT/OR REFORM N INTO KS LATER THIS 
MORNING...AHEAD OF 70+KT MID-LEVEL JET PROGGD TO PUNCH INTO NW 
OK/SWRN KS. HIGH TEMPS TRICKY WITH STRATUS EXTENDING FROM SRN OK SWD 
THRU ERN TX AND DAY SHIFT MAY NEED TO LOWER IF CLOUDS HANG TOUGH.

WARMING H7 TEMPS (+11/12C) WILL EFFECTIVELY INCREASE THE CAP ACROSS 
THE AREA TODAY...AND SHUD HOLD CONVECTION IN CHECK FOR MOST OF THE 
AFTERNOON. DRY LINE SHUD BE ACROSS CNTRL OK BY LATE IN THE 
DAY...AS THE AFOREMENTIONED MID-LEVEL JET PUSHES INTO ERN KS/NRN OK. 
CONVECTIVE INITIATION IS EXPECTED BY LATE AFTERNOON OR EARLY 
EVENING...WITH ETA KF SOLUTION SUGGESTING DEVELOPMENT A LITTLE 
EARLIER THAN OPERATIONAL ETA.

UNLIKE THE PAST FEW SEVERE WEATHER EVENTS...SURFACE-BASED CAPES ARE 
NOT NEARLY AS EXTREME...WITH MESOETA SHOWING 3000-4000 J/KG BY LATE 
AFTERNOON. HOWEVER...SHEAR PROFILES ARE VERY IMPRESSIVE...ESPECIALLY 
IN THE LOW-LEVELS WHERE THE MESOETA DEPICTS 45 KTS OF SLY H85 FLOW. 
WHILE THE HIGHEST SEVERE WEATHER THREAT WILL BE OVER ERN KS/WRN 
MO...CONVECTIVE PARAMETERS ARE SUGGESTIVE OF LONG-TRACK 
SUPERCELLS...ESPECIALLY OVER NE OK IF THE CAP IS BROKEN. DEVELOPMENT 
FARTHER SE ALONG THE DRY LINE INTO SE OK IS STILL IN QUESTION DUE TO 
PRESENCE OF A STRONGER CAP.

MODELS ARE HAVING A HARD TIME HANDLING DRY LINE ON FRI...WITH MESOETA 
KEEPING IT OVER THE FORECAST AREA WHILE THE GFS MIXES IT FARTHER W 
INTO CNTRL/WRN OK. CURRENT FORECAST HAS SLIGHT CHANCE AFTERNOON POPS 
WHICH LOOKS GOOD GIVEN THE UNCERTAINTY IN THE DRY LINE POSITION AND 
CAP STRENGTH.

ANOTHER STRONG SHORTWAVE IS PROGGD TO THE 4-CORNERS REGION BY 06Z 
SAT AND WILL SWING INTO WRN KS BY 18Z. DRY LINE WILL MAKE YET 
ANOTHER PUSH INTO THE FORECAST AREA DURING THE AFTERNOON...WITH WIND 
FIELDS/INSTABILITY SUFFICIENT FOR ANOTHER ROUND OF SEVERE WEATHER. 

LOW-LEVEL MOISTURE WILL F I N A L L Y GET SWEPT E OF THE AREA SAT 
NIGHT AS HIGH PRESSURE BUILDS ACROSS THE SRN PLAINS. DRIER AND 
COOLER WEATHER IS IN STORE FOR SUN AND MON. 

BIG DIFFERENCES NOTED BETWEEN GFS/ECWMF BY TUES...WITH MRF BRINGING 
MOISTURE RAPIDLY NWD WHILE ECMWF DRIVES SFC HIGH TO THE GULF COAST. 
WILL LEAN TOWARD GFS SOLUTION FOR NOW AND BRING A SLIGHT CHANCE OF 
THUNDER TO THE FORECAST FOR TUES.   

TUL   89   69   91   69  / 40   20   20   20  
FSM   88   68   91   67  / 50   30   20   20  
MLC   88   72   90   72  / 30   20   20   20  
BVO   89   67   91   67  / 40   20   20   20  
FYV   85   67   86   66  / 50   30   20   20  
BYV   84   66   86   66  / 50   30   20   20  
MKO   88   69   91   68  / 40   20   20   20  
MIO   86   68   88   66  / 50   40   20   20  
F10   89   70   91   70  / 30   20   20   20  
HHW   87   73   90   71  / 40   20   20   20  

FORECAST ID = 18

.TSA...
AR...NONE.
OK...NONE.





 
 
FXUS64 KTSA 080440
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
1140 PM CDT WED MAY 7 2003

SEVERE THUNDERSTORMS CONTINUE TO TRACK ACROSS WESTERN/SOUTHWESTERN 
OKLAHOMA.  LOW LEVEL JET FIRMLY ESTABLISHED VIA PROFILER NETWORK 
WITH BROAD AREA OF 45-50KT 850MB WINDS ACROSS OK.  EXPECT STRONG 
WARM ADVECTION ZONE TO TRANSLATE INTO EASTERN OKLAHOMA SERVING TO 
SUSTAIN ONGOING CONVECTION WHILE IGNITING ADDITIONAL THUNDERSTORMS.  
DEEP LAYER SHEAR MORE THAN ADEQUATE FOR ELEVATED SUPERCELLS NORTH OF 
THE WARM FRONT.  AT 1130 PM...SURFACE WARM FRONT CONTINUED ALONG THE 
RED RIVER VALLEY WITH NORTHWARD PROGRESS ANTICIPATED OVERNIGHT.  
REPORTS ASSOCIATED WITH WESTERN OK STORMS SUBSTANTIATE LARGE HAIL THREAT 
WITH ISOLATED TORNADO THREAT POSSIBLE FOR STORMS THAT TRACK 
ALONG/SOUTH OF THE WARM FRONT OVERNIGHT.  

FORECAST ID= 07

.TSA...
AR...NONE.
OK...NONE.











 
 
FXUS64 KTSA 080333
AFDTUL

MESOSCALE FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
1035 PM CDT WED MAY 7 2003

03Z SURFACE ANALYSIS PLACED DEEPENING SURFACE LOW OVER NE NEW MEXICO 
WITH WARM FRONTAL BOUNDARY EXTENDING EASTWARD FROM THE SURFACE LOW 
AND CLOSELY FOLLOWING ALONG RED RIVER VALLEY.  CONVECTION THAT 
DEVELOPED EARLY THIS EVENING ALONG DRY LINE IN TX PANHANDLE HAS 
CONTINUED EASTWARD INTO SW OK WITH THE MOST INTENSE STORMS RIDING 
ALONG/SOUTH OF THE WARM FRONTAL BOUNDARY.  CONVECTION SPREADING INTO 
CENTRAL OKLAHOMA CONTINUES TO WEAKEN AS IT PRESSES EASTWARD INTO A 
MORE STABLE AIRMASS.  NEW MODEL DATA SUPPORTS EASTWARD PROGRESSION 
OF ONGOING CONVECTION OVERNIGHT WHILE WARM FRONT SLOWLY LIFTS 
NORTHWARD.  STORMS WHICH MAINTAIN THEMSELVES SOUTH OF THE WARM FRONT 
WILL POTENTIALLY BE SURFACE BASED GIVEN LOW T/TD SPREADS AND WILL 
HAVE THE GREATEST POTENTIAL OF SIGNIFICANT SEVERE WEATHER.  
ADDITIONAL THUNDERSTORMS WILL LIKELY DEVELOP NORTH OF RETREATING 
WARM FRONT WITHIN STRONG LOW LEVEL JET AXIS AND WILL POSE A LARGE 
HAIL THREAT AS ELEVATED INSTABILITY INCREASES WITHIN A STRONGLY 
SHEARED ENVIRONMENT.

FORECAST ID= 07

.TSA...
AR...NONE.
OK...NONE.









 
 
FXUS64 KTSA 080210
AFDTUL

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
905 PM CDT WED MAY 7 2003

INTEND TO LEAVE FORECAST PACKAGE AS IS. ONLY RUC IS AVAILABLE SO FAR 
FROM THE 00Z MODEL RUNS...WHICH SEEMS TO AGREE RATHER WELL WITH 18Z 
RUNS OF THE GFS AND ETA.  EXPECT STRONG WARM ADVECTION TO DEVELOP 
DURING THE NIGHT WITH 40-50 KT SOUTHERLY H8 JET.  ETA IS DEVELOPS 
MOST MID LEVEL RH OVER ERN OK...BUT BOTH ETA AND GFS DEVELOP PRECIP 
BEFORE DAWN.  EXPECT MID CLOUDS TO DEVELOP...FOLLOWED BY SCATTERED 
THUNDERSTORMS.  INSTABILITY IN THE MID LEVELS MAY LET A FEW STORMS 
BECOME SEVERE...AND WILL NEED TO MONITOR FOR THAT POSSIBILITY.  
STORMS THAT DEVELOP SHOULD DEVELOP RAPIDLY...BUT DO NOT EXPECT THAT 
UNTIL WELL AFTER MIDNIGHT...MAYBE 2-5AM.    

FORECAST ID= 2

.TSA...
AR...NONE.
OK...NONE.







 
 
FXUS64 KOUN 080149
AFDOKC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OKLAHOMA
845 PM CDT WED MAY 7 2003

MADE SOME MINOR CHANGES BASED ON LATEST RADAR AND SATELITE TRENDS 
WITH PRECIP AND CLOUD COVER. WILL LIKELY SEE ISOLATED TO SCATTERED 
SHOWERS AND THUNDERSTORMS CONT FOR A COUPLE OF MORE HOURS ACROSS SW 
ZONES WITH GRADUAL DECREASE IN COVERAGE AND INTENSITY WITH LOSS OF 
HEATING. ATTENTION THEN TURNS TO WAA DEVELOPING NORTH OF WARM FRONT 
ACROSS CENTRAL INTO NE OKLAHOMA AFTER MIDNIGHT. LOW LEVELS HAVE SOME 
WORK TO DO WITH 00Z SOUNDING SHOWING STRONG CAPPING INVERSION TO 
OVERCOME HERE IN CENTRAL OK. WINDOW OF OPPORTUNITY MAY BE SMALL HERE 
ACROSS CENTRAL SECTIONS WITH CHANCES LINGERING TOWARD MORNING IN THE 
NORTH AND NE. NO CHANGES PAST FIRST PERIOD. UPDATES OUT SHORTLY. 

30

---------------------------------------------


353 PM CDT WED MAY 7 2003

REPEATED VISITS BY WAVES IN THE GENERALLY WEST-SOUTHWESTERLY UPPER 
FLOW WILL KEEP CHANCES OF SHOWERS AND STORMS IN OUR FORECAST FOR THE 
MAJORITY OF THE NEXT 7 DAYS.  IT APPEARS THAT THE MAIN HIGHLIGHTS 
FOR SEVERE WEATHER WILL BE TONIGHT... THURSDAY... FRIDAY... 
SATURDAY... AND AGAIN ON TUESDAY NIGHT AND WEDNESDAY.  SUNDAY AND 
MONDAY LOOK FAIRLY QUIET AT THIS POINT.

HAVE MADE SOME SIGNIFICANT CHANGES TO THE TEMPERATURE FORECASTS FOR 
THE WEEKEND AND EARLY NEXT WEEK.  GENERALLY LOWERED HIGHS ABOUT 5 TO 
10 DEGREES AND MADE SIMILAR... ALTHOUGH NOT QUITE AS ABRUPT... 
CHANGES TO LOW TEMPERATURES.  BETWEEN THE EXPECTED FRONTAL PASSAGE 
AND CLOUD COVER... DAYTIME HIGHS WILL BE HARD PRESSED TO GET MUCH 
ABOVE THE NEW MRF GUIDANCE.

ALSO MODIFIED POPS SOMEWHAT.  IN HOPES THAT THE MODEL FORECAST OF 
FULL-SCALE FRONTAL PASSAGE WILL ACTUALLY OCCUR... HAVE 
LOWERED/REMOVED POPS SUNDAY.  OBVIOUSLY... IF THE FRONT FAILS TO 
MAKE IT AS FAR AS THE GFS SHOWS... THE FORECAST WILL NEED TO BE PUT 
BACK THE WAY IT WAS.

OKC   71   87   62   88  / 50   30   30   10  
HBR   66   88   57   89  / 30   20   20   10  
SPS   70   91   63   93  / 30   20   20   10  
GAG   57   85   51   86  / 40   10   10    0  
PNC   69   85   59   86  / 50   40   30   10  
DUA   73   89   70   91  / 30   40   30   20  

FORECAST ID = 23 = CMS

.OUN...
OK...NONE.
TX...NONE.




 
This data is from the IWIN (Interactive Weather Information Network)