Severe Thunderstorm Warning 42, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
245 AM CST SAT MAR 25 2000

CURRENT FORECAST PROBLEMS REVOLVE AROUND POSITION OF SURFACE
BOUNDARIES NEXT COUPLE OF DAYS.  WEAK FRONT LOCATED ACROSS NORTHWEST
ARKANSAS INTO EAST CENTRAL OKLAHOMA PROGGED TO STALL AROUND THE RED
RIVER AND BECOME FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT LATER
TODAY.  ETA AND NGM MORE SIMILAR IN THE PRECIP FIELDS THAN WHAT THE
AVN IS SHOWING.  IF THIS FIRST BATCH OF PRECIP FORMS WHERE
ADVERTISED...LOOKS TO MOVE EAST AS ADDITIONAL WAA PRECIP DEVELOPS AND
MOVES NORTHWARD SAT NIGHT INTO SUNDAY.  NEXT COLD FRONT COMING SOUTH
SUNDAY AFT/NIGHT SHOULD PROVIDE BETTER LIFT OF MOIST AIR AND PRODUCE
ADDITIONAL PRECIP FOR MOST OF CWA.

TEMPERATURES COULD BE A BIT TRICKY OVER NEXT COUPLE OF DAYS AS WELL
GIVEN UNCERTAINTIES IN THE POP FORECAST.  NGM MOS MADE A RATHER LARGE
JUMP IN MAX TEMPS FROM THE 12Z TO 00Z RUNS...ESPECIALLY FOR
SUNDAY...AS THE AVN MOS STAYED THE SAME.  TENDED TO STAY CLOSER TO
THE AVN TEMPS AT THIS TIME.

INTO MONDAY NEW MRF AND AVN DRYING THINGS OUT BEFORE THE NEXT UPPER
LOW MOVES IN TUESDAY/WEDNESDAY.  MRF QUITE SIMILAR TO YESTERDAYS WITH
TRACK OF THIS NEXT SYSTEM OVER OKLAHOMA ONLY A BIT SLOWER.  CANADIAN
MODEL LOOKS CLOSER TO THE MRF AS THE NOGAPS MAINTAINS ITS TRACK
FURTHER SOUTH.  WILL MAKE A FEW ADJUSTMENTS TO EXTENDED BUT MAJORITY
WILL REMAIN AS IS.

HOWIESON
FCSTID = 44
...VERY PRELIM NUMBERS...
TUL   73  50  72  52 /   5  20  40  30
FSM   76  51  74  52 /  10  30  40  40
MLC   76  53  73  52 /  20  30  50  40
BVO   72  47  71  51 /   5  20  40  30
FYV   71  48  71  50 /   5  20  30  40
BYV   71  48  71  50 /   5  20  30  40
MIO   72  48  72  50 /   5  20  30  40
MKO   73  50  72  52 /   5  20  40  30
F10   73  50  72  52 /   5  20  40  30
HHW   77  55  75  55 /  20  40  50  40

.TUL...
AR...NONE.
OtK...NONE.

ARZ001-002-010-011-019-020-029-OKZ049-053>076-261200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CST SAT MAR 25 2000

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE EARLY THIS MORNING IN FAR
SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS WITH A FEW SEVERE STORMS
POSSIBLE AGAIN LATE THIS AFTERNOON AND THIS EVENING IN SOUTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS...

.SYNOPSIS...
A SURFACE LOW WAS IN NORTHCENTRAL TEXAS EARLY THIS MORNING WITH A WARM
FRONT EXTENDING FROM THE LOW INTO SOUTHEAST OKLAHOMA. AN UPPER LEVEL
DISTURBANCE WILL MOVE ACROSS THE AREA EARLY THIS MORNING WITH ANOTHER
DISTURBANCE MOVING INTO THE REGION LATE THIS AFTERNOON. THE SURFACE LOW
IS EXPECTED TO MOVE INTO SOUTHCENTRAL OKLAHOMA WITH THE WARM FRONT
LIFTING INTO NORTHWEST ARKANSAS.

.PRIMARY HAZARD...
SEVERE THUNDERSTORMS WITH LARGE HAIL WILL BE THE PRIMARY HAZARD. EARLY
MORNING STORMS ARE EXPECTED TO MOVE EAST OF THE AREA BY MID
MORNING...BUT ADDITIONAL STORMS ARE EXPECTED TO DEVELOP BETWEEN 3PM AND
9PM LATER TODAY. HAIL TO 2 INCHES IN DIAMETER AND STRONG WINDS WILL BE
POSSIBLE WITH THE STORMS LATE THIS AFTERNOON AND THIS EVENING.

.DISCUSSION...
ELEVATED INSTABILITY INCREASED RAPIDLY OVERNIGHT IN SOUTHEAST OKLAHOMA
AND SPREAD INTO NORTHWEST ARKANSAS EARLY THIS MORNING AHEAD OF THE UPPER
SYSTEM. THUNDERSTORMS WILL MOVE EASTWARD AND SHOULD BE OUT OF THE AREA
BY MID MORNING.

SURFACE DEWPOINTS ARE EXPECTED TO INCREASE INTO THE UPPER 50S TO LOWER
60S LATER TODAY ALONG AND SOUTH OF THE WARM FRONT. THIS WILL CREATE A
VERY UNSTABLE AIRMASS WITH SURFACE BASED CAPES FROM 1000 TO 2000 J/KG BY
LATE AFTERNOON FROM MCALESTER TO FAYETTEVILLE SOUTHWARD. THE SURFACE
BOUNDARY SHOULD ACT AS A FOCUS WITH ANOTHER UPPER DISTURBANCE HELPING TO
INITIATE CONVECTION. THE STORMS ARE EXPECTED TO LINGER IN NORTHWEST
ARKANSAS DURING THE EARLY EVENING HOURS BEFORE ENDING BY LATE EVENING.

.SPOTTER ACTIVATION...
SEVERE STORMS ARE EXPECTED TO BE BRIEF IN NATURE EARLY THIS MORNING AND
SPOTTER ACTIVATION IS NOT ANTICIPATED. SPOTTER ACTIVATION MAY BE
REQUIRED THIS AFTERNOON AND EARLY THIS EVENING IN SOUTHEAST OKLAHOMA AND
NORTHWEST ARKANSAS.  STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT
AGENCIES SHOULD STAY TUNED TO THE LATEST INFORMATION.

A GRAPHICAL VERSION OF THE HAZARDOUS WEATHER OUTLOOK...ALONG WITH OTHER
DETAILED FORECASTS...CAN BE OBTAINED VIA THE INTERNET AT
WWW.NWSTULSA.NOAA.GOV.