Tornado and Flash Flooding in Oklahoma, April 23 to 26, 2004

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
347 AM CDT FRI APR 23 2004

.DISCUSSION...
POTENT WX SYSTEM OVER THE SRN ROCKIES THIS MORNING WILL BE IMPACTING
THE FA THE NEXT 24 TO 48 HOURS. QSTNRY SFC FRONT EXTENDS FROM SERN
OK INTO WRN N TX THIS MORNING AND THIS FEATURE IS NOT EXPECTED TO
MOVE MUCH DURING THE DAY. MOIST AIR WILL CONTINUE TO FLOW NWD INTO
THE FRONTAL ZONE TODAY. WITH SOME BREAKS IN THE CLOUDS IN SRN OK/N
TX AMS EXPECTED TO BECOME INCREASINGLY UNSTABLE BY AFTN. WIND FIELDS
WILL BE INCREASING AS MID LVL SYS OVER THE ROCKIES ADVANCES EWD.
EXPECT SVR STORMS TO DEVELOP BY MID AFTN IN THE VCNTY OF THE SFC
BNDRY AS PER SWODY1. WIDESPREAD SHOWERS AND TSTMS EXPECTED TO
DEVELOP NORTH OF THE FRONT LATER TODAY AND THROUGH TONIGHT WITH STG
ISENT LIFT DVLPG. COULD STILL SEE SOME SEVERE HAIL PRODUCERS WELL
NORTH OF THE SFC BOUNDARY.  HEAVY RAIN IS ALSO A THREAT...ESP
TONIGHT AS LIFT INCREASES ALONG AND JUST NORTH OF THE FRONT. WILL
NOT GO WITH FLOOD WATCH ATTM DUE TO UNCERTAINTY OVER WHERE HEAVY
RAIN WILL BE FOCUSED BUT LATER SHIFTS MAY NEED TO ISSUE FLOOD WATCH
AS AREA OF CONCERN BECOMES BETTER DEFINED. HVY RAIN/SEVERE WX THREAT
SHIFTS INTO ERN PARTS OF THE FA SATURDAY AS UPR SYS BEGINS TO OPEN
UP AND LIFT NEWD AND SFC FNT PUSHES SLOWLY EWD. SYSTEM FINALLY
CLEARS THE AREA SUNDAY WITH PLEASANT WX EXPECTED THROUGH AT LEAST
MID WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  67  55  65  49 /  80  90  80  30
HOBART OK         64  52  64  48 /  80  90  60  10
WICHITA FALLS TX  76  58  66  50 /  70  90  70  30
GAGE OK           54  46  58  44 /  80  70  30  10
PONCA CITY OK     63  53  63  47 /  80  90  80  30
DURANT OK         81  65  71  53 /  60  70  80  60

&&

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

&&

2

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
700 AM CDT FRI APR 23 2004

OKZ004>048-050>052-TXZ083>090-231700-

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

.DAY ONE...TODAY AND TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
WESTERN NORTH TEXAS AND A SMALL PART OF SOUTHWEST OKLAHOMA. THERE IS
A SLIGHT RISK TO THE NORTH OF THE MODERATE RISK ACROSS THE REMAINDER
OF WESTERN NORTH TEXAS AND MUCH OF OKLAHOMA.

LOCATION...
THE MODERATE RISK AREA IS ALONG AND SOUTH OF A LINE FROM TRUSCOTT TO
VERNON TEXAS... TO WALTERS AND TERRAL OKLAHOMA. THE SLIGHT RISK AREA
IS NORTH OF THE MODERATE RISK AREA AND SOUTH OF A LINE FROM LAVERNE
TO WAYNOKA... TO ENID... TO CUSHING.

TIMING...
SEVERE THUNDERSTORMS ARE MOST LIKELY FROM 3 PM THROUGH THE EVENING
HOURS.

IMPACTS...
HAIL TO THE SIZE OF BASEBALLS AND WINDS TO 70 MPH ARE EXPECTED IN
THE MODERATE RISK AREA... ALONG WITH THE POTENTIAL FOR TORNADOES. IN
THE SLIGHT RISK AREA...HAIL TO THE SIZE OF QUARTERS IS EXPECTED.

RECOMMENDED ACTIONS...
EMERGENCY MANAGEMENT AND STORM SPOTTER GROUPS SHOULD BE PREPARED FOR
SEVERE WEATHER OPERATIONS FROM MID AFTERNOON THROUGH THE EVENING
HOURS.

DISCUSSION...
MID AND UPPER LEVEL FORCING AHEAD OF AN UPPER LEVEL LOW LOCATED OVER
NORTHWEST NEW MEXICO THIS MORNING HAS LEAD TO THE DEVELOPMENT OF
SCATTERED SHOWERS AND THUNDERSTORMS ACROSS WESTERN OKLAHOMA AND THE
OKLAHOMA AND TEXAS PANHANDLES THIS MORNING. THIS ACTIVITY IS
EXPECTED TO CONTINUE AND WILL LIKELY EXPAND INTO CENTRAL OKLAHOMA
AND WESTERN NORTH TEXAS THROUGHOUT THE MORNING HOURS. MOST OF THIS
ACTIVITY WILL BE ELEVATED IN NATURE AS THE STORMS WILL BE DEVELOPING
TO THE NORTH OF A STATIONARY SURFACE FRONT LOCATED ACROSS NORTH
TEXAS AND SOUTH CENTRAL AND SOUTHEAST OKLAHOMA. THE MAIN THREAT FROM
THESE STORMS WILL BE LARGE HAIL.

BY THIS AFTERNOON... THIS STATIONARY FRONT IS EXPECTED TO MOVE
SLOWLY NORTH ACROSS WESTERN NORTH TEXAS INTO FAR SOUTHWEST OKLAHOMA
THEN EAST ACROSS SOUTHERN OKLAHOMA. AS THIS OCCURS THE AIRMASS SOUTH
OF THE FRONT IS EXPECTED TO BECOME INCREASINGLY UNSTABLE. IN
ADDITION LOW LEVEL WIND FIELDS WILL BE INCREASINGLY FAVORABLE FOR
THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS ACROSS THIS AREA. THESE
STORMS WILL BE CAPABLE OF VERY LARGE HAIL... DAMAGING STRAIGHT-LINE
WINDS AND TORNADOES.

ALTHOUGH THE THREAT OF SEVERE WEATHER WILL DECREASE BY LATE
EVENING... AS THE UPPER LEVEL LOW CONTINUES TO AFFECT THE AREA
OVERNIGHT... SEVERE THUNDERSTORMS WILL STILL BE POSSIBLE. LARGE HAIL
WILL BECOME THE PRIMARY SEVERE WEATHER THREAT OVERNIGHT.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT SATURDAY APR 24.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...100 PERCENT.

OTHER HAZARDOUS WEATHER...
TORRENTIAL RAIN MAY ACCOMPANY THUNDERSTORMS THIS AFTERNOON AND
TONIGHT...DUE TO SLOW MOVEMENT...AND OR REPEATED ROUNDS OF HEAVY
RAIN FROM ADDITIONAL THUNDERSTORMS OVERNIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY...

THUNDERSTORM OUTLOOK...
THUNDERSTORMS WILL POSSIBLY BE ONGOING SATURDAY MORNING ACROSS MUCH
OF OKLAHOMA AND WESTERN NORTH TEXAS AS THE SLOW MOVING UPPER LEVEL
LOW MAKES ITS WAY EAST ACROSS THE SOUTHERN PLAINS. THE POTENTIAL
WILL EXIST BY SATURDAY AFTERNOON ACROSS SOUTH CENTRAL AND SOUTHEAST
OKLAHOMA FOR SOME OF THESE STORMS TO BE ACCOMPANIED BY LARGE HAIL.

OTHER HAZARDOUS WEATHER...
NONE.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT NOON
TODAY.

30

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
827 AM CDT FRI APR 23 2004

OKZ020-231345-
PAYNE OK-
827 AM CDT FRI APR 23 2004

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR PAYNE COUNTY.

A STRONG THUNDERSTORM WAS LOCATED OVER GLENCOE AT 827 AM CDT...MOVING
NORTHEAST AT 20 MPH.

STORM INTENSITY IS INCREASING AND SEVERE WEATHER MAY DEVELOP RAPIDLY.

PEOPLE IN PAYNE COUNTY SHOULD MONITOR THE WEATHER SITUATION CLOSELY.
LISTEN FOR WARNINGS AND REMAIN ALERT FOR THREATENING WEATHER
CONDITIONS.

JAMES