Severe Thunderstorm Warning 277, NWS Tulsa, OK

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
340 PM CDT THU JUL 17 1997

UPPER LOW OVER OSAGE COUNTY CONTINUES TO FOCUS CONVECTION OVER
WATER-LOGGED NWRN ZONES...MEANWHILE OTHER STRONG CONVECTION HAS
FIRED UP ALONG OUTFLOW BOUNDARY IN OKFUSKEE AND OKMULGEE COUNTIES.
FEEL THAT UPPER-LOW WILL BE THE MAJOR PLAYER IN THE PRECIP GAME
OVER NEXT 24 HOURS.  WILL GO WITH ETA/AVN MOVEMENT OF THIS FEATURE
AND ASSOCIATED PRECIP.  BOTH OF THESE MODELS SLIDE THE LOW SLOWLY
WEST OR SOUTHWEST OVER THE NEXT 36 HOURS AS UPPER RIDGE WEAKENS
WITH THE APPROACH OF T.S. DANNY.

WILL EXTEND/EXPAND FFA FROM OSAGE TO OKFUSKEE COUNTY FOR TONIGHT AS
UPPER-LOW MOVES SLOWLY SOUTHWESTWARD NEAR THAT AREA.  EACH OF THESE
COUNTIES HAS ALREADY HAD AT LEAST LOCALLY HEAVY RAIN TODAY...WITH
WIDESPREAD HEAVY RAIN OVER OSAGE AND PAWNEE COUNTIES.

FURTHER EAST AND SOUTH EXPECT THAT WIDELY SCATTERED SHRA/TSRA WILL
DISSIPATE EARLY THIS EVENING. WILL GET LAST LOOK AT RADAR BEFORE
ADDING EVENING POPS ACROSS THESE AREAS.

WILL LIKELY SEE SOME REMNANT SHRA/TSRA OVER WATCH AREA INTO THE
MORNING HOURS TOMORROW...BEFORE IT MOVES COMPLETELY OUT OF THE
AREA.  THEREFORE WILL LEAVE CHANCE POPS IN WRN ZONES TOMORROW WITH
WDLY SCT CONVECTION EXPECTED AGAIN TOMORROW AFTERNOON OVER ENTIRE
FA.  THE APPROACH OF T.S. DANNY TO GULF COAST MAY HELP SUPPRESS
THIS DIURNAL ACTIVITY ON SATURDAY...BUT WITH WEAK CAP AND SOME
INSTABILITY WILL LEAVE SLT CHC IN FOR ENTIRE AREA ON SAT.

AS FOR TEMPS FWC/FAN ARE IN VERY GOOD AGREEMENT...BUT NEITHER ONE
OF THEM THINK IT WILL RAIN.  ONLY DEVIATION FROM MOS TEMPS WILL BE
TO COOL THINGS OFF WHERE RAIN IS EXPECTED.

...19...

...:PRELIM NUMBERS...
TUL 72/91 74/93 4412
FSM 72/95 70/94 1212
MLC 71/93 72/93 3312
BVO 68/90 71/94 5412
FYV 67/91 68/91 1212
IDB 69/95 69/94 1212
BYV 66/92 67/92 1212

.TUL...
OK...FFA TONIGHT ZNS 54/59/64/65.
AR...NONE.

ARZ001-002-010-011-019-029-OKZ054>076-181200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT THU JUL 17 1997

A FEW SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA
THIS AFTERNOON THROUGH TONIGHT.  ISOLATED SEVERE THUNDERSTORMS ARE
POSSIBLE OVER NORTHWEST ARKANSAS THIS AFTERNOON AND THIS EVENING.

A SLOW MOVING UPPER LEVEL SYSTEM WAS LOCATED IN NORTH CENTRAL
OKLAHOMA THIS AFTERNOON. THIS SYSTEM SHOWED UP AS A SMALL
CIRCULATION CENTER ON SATELLITE IMAGERY...AND CONTINUED TO SUPPORT
THUNDERSTORM DEVELOPMENT ACROSS OSAGE AND PAWNEE COUNTIES AT 100
PM. THE UPPER LEVEL SYSTEM IS EXPECTED TO MOVE SLOWLY SOUTH THIS
AFTERNOON AND TONIGHT.

A RAIN-COOLED BOUNDARY...CREATED BY THE THUNDERSTORMS ACROSS OSAGE
AND PAWNEE COUNTIES...WAS LOCATED FROM NEAR JAY TO WAGONER TO
OKEMAH EARLY THIS AFTERNOON. THIS BOUNDARY WILL REMAIN STATIONARY
THROUGH THE AFTERNOON HOURS.

THE BEST CHANCE OF THUNDERSTORMS WILL BE NEAR THE UPPER LEVEL
SYSTEM AND ALONG THE RAIN-COOLED BOUNDARY. THE AIRMASS WILL BE VERY
UNSTABLE IN MOST AREAS THIS AFTERNOON...AND SOME OF THE STORMS
COULD BE SEVERE.

ALTHOUGH THE EFFECTS OF THE UPPER LEVEL SYSTEM WILL REMAIN CONFINED
TO EASTERN OKLAHOMA...ISOLATED SEVERE THUNDERSTORMS WILL ALSO BE
POSSIBLE OVER NORTHWEST ARKANSAS MAINLY DURING THE HEAT OF THE
AFTERNOON. THE THREAT OF SEVERE THUNDERSTORMS OVER NORTHWEST
ARKANSAS WILL DIMINISH AFTER SUNSET...WHILE SEVERE THUNDERSTORMS
COULD LINGER INTO THE NIGHT OVER EASTERN OKLAHOMA.

STORMS ARE EXPECTED TO BE SLOW MOVING...SO IN ADDITION TO THE
THREAT OF LARGE HAIL AND STRONG DAMAGING WINDS...VERY HEAVY RAIN
WILL BE POSSIBLE.

EMERGENCY MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS SHOULD
MONITOR THE LATEST WEATHER CONDITIONS AND BE READY FOR POSSIBLE
ACTIVATION.