Severe Thunderstorm Warning 317, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
300 PM CDT TUE JUN 13 2000

IT LOOKS WET TONIGHT.  LATEST RADAR IMAGES SHOWING ECHOES ALREADY
BEGINNING TO DEVELOP IN TEXAS AND WESTERN BEAVER COUNTIES OF THE
PANHANDLE.  EXPECT WIDESPREAD THUNDERSTORMS TO CONTINUE TO DEVELOP
ALONG THE FRONT... ESPECIALLY ACROSS NORTHERN AND CENTRAL OKLAHOMA.
CONVECTION MAY BE A BIT MORE SCATTERED IN NATURE FARTHER SOUTHWEST.
THINK THAT THERE WILL BE SOME LOCALLY HEAVY RAINFALL AS WELL...
AGAIN ESPECIALLY NORTH.  FLASH FLOOD GUIDANCE NUMBERS ARE RELATIVELY
HIGH AND AM NOT SURE ENOUGH ABOUT HOW WIDESPREAD THE HEAVY RAINFALL
WILL BE... SO AM NOT INCLINED TO GO WITH A FLASH FLOOD WATCH
ANYWAY.  THE SURFACE FRONT ROLLS THROUGH OVERNIGHT AND TOMORROW.
NGM IS MUCH SWIFTER BRINGING IT THROUGH... AND WENT WITH THE
SLIGHTLY SLOWER MOVEMENT OF THE FRONT... ALTHOUGH ANY OUTLOW WILL
MUDDLE THE PICTURE.  CONVECTION WILL LIKELY TO EVOLVE INTO AN MCS OR
SQUALL LINE AND WILL PROBABLY BE CONTINUING IN THE EASTERN PORTION
OF THE FA AT THE BEGINNING OF THE SECOND PERIOD.

THE TIMING OF THE UPPER SYSTEM LOOKS A BIT MORE LIKE WE WILL HAVE A
BREAK ON THURSDAY BETWEEN THIS SYSTEM MOVING OUT AND THE NEXT
DEVELOPING TROF.  AFTER THIS ONE MOVES OUT THE POPS INCREASE AGAIN
LATE FRIDAY.  BUT WITH THE CURRENT TIMING WILL REMOVE AND/OR LESSEN
POPS ACROSS THE AREA THURSDAY.

COORD W/ ICT.

...SPEG.
OKC   68  80  64  87 /  80  40  10  10
HBR   67  82  62  90 /  60  20  10   0
SPS   70  83  66  91 /  50  20  10   0
GAG   61  81  58  88 /  80  20   0   0
PNC   65  80  62  86 /  90  40  10   0
DUA   70  79  62  85 /  60  60  20  10

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

OKZ004>048-050>052-TXZ083>090-132000-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1240 PM CDT TUE JUN 13 2000

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS EVENING AND
TONIGHT ACROSS NORTHERN OKLAHOMA... NORTH OF A LINE FROM ARNETT TO
OKARCHE TO CHANDLER. THERE IS ALSO A SLIGHT RISK OF SEVERE
THUNDERSTORMS TONIGHT ACROSS WESTERN NORTH TEXAS AND MOST OF THE REST
OF CENTRAL AND SOUTHWEST OKLAHOMA... NORTHWEST OF A LINE FROM
MARIETTA TO COALGATE. DAMAGING WINDS... VERY HEAVY RAINFALL... AND
LARGE HAIL WILL BE THE PRIMARY THREATS.

DISCUSSION...A COLD FRONT WILL MOVE SOUTHEAST TO A LINE FROM
CENTRAL KANSAS... TO EXTREME NORTHWEST OKLAHOMA... AND INTO THE
NORTHERN TEXAS PANHANDLE... BY AROUND 7 PM THIS EVENING.
MEANWHILE...AFTERNOON HEATING COMBINED WITH LARGE AMOUNTS OF LOW
LEVEL MOISTURE WILL RESULT IN A VERY UNSTABLE AIRMASS ACROSS THE
SOUTHERN PLAINS. STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO
DEVELOP LATE THIS AFTERNOON AND EARLY THIS EVENING ALONG THE FRONT
AND MOVE INTO NORTHERN OKLAHOMA DURING THE EARLY TO MID EVENING.
THUNDERSTORMS ARE EXPECTED TO DEVELOP INTO A LARGE SQUALL LINE BY THE
TIME THEY MOVE INTO CENTRAL AND SOUTHWEST OKLAHOMA DURING THE
OVERNIGHT HOURS...REACHING WESTERN NORTH TEXAS AND SOUTHEAST
OKLAHOMA LATE TONIGHT.

THE PRIMARY SEVERE THREAT WILL BE DAMAGING WINDS. HOWEVER... THE
VERTICAL WIND PROFILE MAY INITIALLY SUPPORT A FEW SUPERCELL
THUNDERSTORMS. THESE STORMS WILL BE CAPABLE OF PRODUCING VERY LARGE
HAIL AND PERHAPS A FEW TORNADOES IN THE MODERATE RISK AREA THIS
EVENING. LOCALLY HEAVY RAINFALL ALSO WILL BE LIKELY.

THE THREAT OF LARGE HAIL AND DAMAGING WINDS WILL CONTINUE WELL INTO
THE NIGHT... BUT SHOULD DECREASE BY THE TIME THE STORMS REACH
SOUTHEAST OKLAHOMA LATE TONIGHT.

SPOTTER ACTIVATION MAY BE REQUIRED TOWARDS SUNSET AND INTO THE
EVENING HOURS ACROSS NORTHERN OKLAHOMA. SPOTTERS IN CENTRAL AND
SOUTHWEST OKL<AHOMA... AND WESTERN NORTH TEXAS... MAY REQUIRE
ACTIVATION DURING THE LATE EVENING AND OVERNIGHT HOURS.

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