Hail in Oklahoma, January 12, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
333 PM CST WED JAN 12 2005

.DISCUSSION...
STRONG UPPER LEVEL TROF MOVING FAIRLY RAPIDLY EWD FROM OK/TX
PANHANDLE REGION THRU THIS EVENING. RELATIVELY NARROW LINE OF
STRONG/LOW END SVR TSTORMS EXPECTED TO FILL IN OVER THE NEXT COUPLE
HOURS ALONG AXIS CURRENTLY DEPICTED NICELY BY AXIS OF INITAL
DEVELOPMENT JUST EAST OF LAWTON. THIS LINE SHUD EXPAND NWD/SWD FROM
CURRENT CELLS AND SWEEP EWD THRU THE EVENING. CURRENTLY..HAVE IT
TIMED TO EXIT THE FAR SE COUNTIES OF OUN CWA BY AROUND 06Z.  SHEAR
VECTOR ORIENTATION RELATIVE TO INITATION BOUNDARY SHUD RESULT IN A
SQUALL LINE..BUT COMBINATION OF STRONG LOW LEVEL SHEAR AND VERY
HUMID BOUNDARY LAYER AND NEAR -20 TEMPS AT 500 MB MAY RESULT IN SOME
EMBEDDED SUPERCELLULAR STRUCTURES AND A SMALL ATTENDANT TORNADO
THREAT..ESP ALONG AND JUST E OF I 44 CORRIDOR.  UPPER TROF AXIS TO
PIVOT ACROSS NW THIRD OF OK THIS EVENING WITH VERY COLD TEMPS ALOFT.
QUICK ONSET OF STRONG COLD ADVECTION SHUD ACT TO LIMIT PRECIP
POTENTIAL THIS AREA..BUT WILL KEEP 30 POPS FOR SOME LIGHT SNOW OR
FREEZING DRIZZLE UNDERNEATH MAIN TROF AXIS FOR MOST OF THE NIGHT.
ALSO EXPECT A 2-4 HOUR PERIOD OF RATHER STRONG WINDS ACROSS WRN OK..
AND EVENTUALLY SWD INTO N TEXAS THIS EVE BEHIND COLD FRONT WHERE
STRONG COLD ADVECTION WILL BE SUPERIMPOSED WITH 6-9 MB/3 HR PRESSURE
RISES..BUT BEST PRESSURE RISES WILL TRANSLATE SWD THRU TX
PANHANDLE.. PERHAPS LIMITING WINDS SOMEWHAT IN OUN CWA.

FORECAST FOR MUCH OF THE REMAINING SEVEN DAY PERIOD IS VERY
DIFFICULT. AS LONG AS EXPANSIVE ARCTIC AIRMASS REMAINS ACROSS MUCH
OF THE CENTRAL/NRN US /AS IT IS PROGGED TO DO THRU THE MIDDLE OF
NEXT WEEK/ THERE WILL BE PERIODIC SURGES OF SHALLOW LOW LEVEL COLD
AIR TO AFFECT MUCH OF OKLAHOMA..AND PERHAPS INTO N TEXAS. IT WILL BE
VERY DIFFICULT TO GET THE EXACT TIMING OF THESE SURGES..AND
SUBSEQUENT COLD AIR EROSION..BUT CURRENT FEELING IS THAT FAR SRN
BOUNDARY OF COLDER AIR MAY END UP FARTHER SOUTH THAN WHERE CURRENT
MODEL RUNS SUGGEST.   BEST GUESS RIGHT NOW BRINGS REINFORCING SHOT
SWD ON FRIDAY INTO NRN OK..WITH BOUNDARY THEN PRESSING SLOWLY SWD
INTO SAT.  THIS MAY BE ACCOMPANIED BY MORE FOG AND FREEZING
DRIZZLE.  ONSET OF WAA PATTERN LATE SUN/MON MAY ALSO BRING MORE FZDZ
AND FOG.  BRIEF WARM UP TUE AHEAD OF NEXT COLD AIR SURGE CURRENTLY
SCHEDULED FOR TUE NITE/WED..BUT THIS IS SUBJECT TO CHANGE. THANKS TO
SURROUNDING OFFICES AND SPC FOR COORD.
 MILLER

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  31  38  23  34 /  60  10  10  10
HOBART OK         30  41  25  40 /  10  10  10  10
WICHITA FALLS TX  33  44  29  43 /  50  10  10  10
GAGE OK           21  36  19  31 /  30  10  10  10
PONCA CITY OK     29  32  19  29 /  60  10  10  10
DURANT OK         38  45  30  38 /  70  10  10  10

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
.OK...NONE.
.TX...NONE.

&&

HAZARDOUS WEATHER OUTLOOK...CORRECTED PROBABILITY NUMBERS...
NATIONAL WEATHER SERVICE NORMAN OK
1200 PM CST WED JAN 12 2005

OKZ004>048-050>052-TXZ083>090-131300-

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM AROUND MID
AFTERNOON INTO TONIGHT ACROSS APPROXIMATELY THE CENTRAL THIRD
OF OKLAHOMA AND PARTS OF WESTERN NORTH TEXAS.

LOCATION...
THE SLIGHT RISK AREA COVERS LOCATIONS GENERALLY SOUTH AND EAST OF A
LINE EXTENDING FROM MEDFORD...TO FAIRVIEW...TO HINTON...TO
LAWTON...TO JUST EAST OF WICHITA FALLS.

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE FROM 3 PM
THROUGH AROUND 10 PM.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE
RISK AREA SHOULD PLAN FOR SEVERE WEATHER OPERATIONS FROM THIS
AFTERNOON UNTIL LATE THIS EVENING.

DISCUSSION...
PORTIONS OF CENTRAL AND SOUTHEAST OKLAHOMA AND WESTERN NORTH TEXAS
WILL BE ON THE WESTERN EDGE OF ANTICIPATED THUNDERSTORM DEVELOPMENT
THIS AFTERNOON AND EVENING. AS A VERY STRONG STORM SYSTEM APPROACHES
THE REGION... THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR AND
EAST OF A DRYLINE... WHICH IS EXPECTED TO EXTEND FROM A SURFACE LOW
PRESSURE SYSTEM OVER NORTHERN OKLAHOMA...SOUTHWARD DOWN THE HIGHWAY
58 CORRIDOR LATE THIS AFTERNOON. INSTABILITY AND DEEP LAYER WIND
SHEAR WILL BE SUFFICIENT TO SUPPORT SEVERE THUNDERSTORMS...WITH
LARGE HAIL AND DAMAGING WIND GUSTS THE PRIMARY CONCERNS. A LIMITING
FACTOR TO HOW FAR WEST ANY DEEP CONVECTION WILL OCCUR IS A STRONG
CAPPING INVERSION.

PROBABILITY TABLE...
VALID THROUGH 700 AM CST THURSDAY JAN 13.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...60 PERCENT.

OTHER HAZARDOUS WEATHER...
PATCHY DENSE FOG WILL LIMIT VISIBILITIES TO LESS THAN 1/4 MILE EARLY
THIS AFTERNOON ACROSS EXTREME NORTH-CENTRAL OKLAHOMA. ALSO...STRONG
NORTHWEST WINDS AT 30 TO 40 MPH WITH HIGHER GUSTS WILL OCCUR BEHIND
THE COLD FRONT LATE THIS AFTERNOON AND TONIGHT ACROSS THE WESTERN
THIRD OF OKLAHOMA AND ALL OF WESTERN NORTH TEXAS.

LIGHT FREEZING DRIZZLE WILL BE POSSIBLE OVER MAINLY THE NORTHERN
TWO-THIRDS OF OKLAHOMA TONIGHT AS COLD AIR FILTERS IN BEHIND A COLD
FRONT. NO SIGNIFICANT PROBLEMS ARE ANTICIPATED...AS ANY
PRECIPITATION WILL BE LIGHT AND BRIEF.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

THUNDERSTORM OUTLOOK...
NO THUNDERSTORMS ARE FORECAST.

OTHER HAZARDOUS WEATHER...
OKLAHOMA WILL REMAIN ON THE FAR SOUTHERN EXTENT OF A VERY COLD
ARCTIC AIRMASS CENTERED OVER THE NORTHERN UNITED STATES THROUGH THE
EARLY PART OF NEXT WEEK... WITH THE LEADING EDGE OF THE ARCTIC AIR
LIKELY TO WAFFLE BACK AND FORTH FROM SOUTH TO NORTH THROUGH THE
WEEKEND AND EARLY NEXT WEEK OVER THE CENTRAL AND SOUTHERN PLAINS.
CURRENTLY... IT APPEARS THAT ANOTHER SOUTHWARD PUSH OF SHALLOW
ARCTIC AIR WILL AFFECT OKLAHOMA AND NORTH TEXAS BEGINNING SATURDAY
INTO SUNDAY... WITH THE COLD AIR THEN RETREATING NORTHWARD ON
MONDAY.  SOME FOG AND DRIZZLE OR FREEZING DRIZZLE IS POSSIBLE
SATURDAY AND SATURDAY NIGHT WITH THE SOUTHWARD PUSH OF ARCTIC AIR...
AND AGAIN SOMETIME MONDAY INTO TUESDAY AS THE COLDER AIR IS
DISPLACED BACK TO THE NORTH.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT 7AM
THURSDAY.

MAXWELL