Severe Thunderstorm Warning 220, NWS Norman, OK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
410 AM CDT FRI MAY 5 2000

UPPER LOW LOCATED NEAR THE OK/AR BORDER WILL DRIFT SLOWLY
EAST/NORTHEAST TODAY AND TONIGHT TOWARDS THE MISSISSIPPI VALLEY.
WIDELY SCATTERED CONVECTION POSSIBLE AROUND THIS SYSTEM... WITH BEST
CHANCES LIKELY BEING IN THE VICINITY OF A WEAK LOW LEVEL TROUGH IN
NORTHERN TEXAS. WILL GO WITH MAINLY A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS TODAY ACROSS THE SOUTHERN PORTION OF THE AREA. THE
UPPER FLOW SHOULD TO STEER CONVECTION TOWARDS THE SOUTHEAST THUS
TENDING TO LIMIT ITS NORTHWARD SPREAD DEEPER INTO THE FORECAST AREA.
A SLIM POSSIBILITY OF A STORM WILL ALSO EXIST ACROSS THE CENTRAL
AND NORTH CENTRAL PORTIONS OF OKLAHOMA... BUT PROBABLY TOO LOW TO
MENTION AT THIS TIME. HOWEVER... AS LOW LEVEL JET STRENGTHENS ACROSS
CENTRAL SECTIONS LATE TONIGHT... COULD SEE WIDELY SCATTERED
SHOWERS/THUNDERSTORMS DEVELOP IN THE MOISTURE/WARM ADVECTION FIELDS.
AS A RESULT OF THE STRONG WARM ADVECTION... CAP SHOULD STRENGTHEN
ACROSS THE AREA ON SATURDAY... AND SUPPRESS FURTHER CHANCES FOR
CONVECTION MOST AREAS. AN ISOLATED STORM OR TWO POSSIBLE NEAR THE
DRYLINE SATURDAY AFTERNOON... JUST WEST OF THE AREA... BUT ACTIVITY
SHOULD WEAKEN QUICKLY BY SUNSET... WITH ONLY A MINIMAL CHANCE OF
REACHING THE WESTERN ZONES.

LOW CLOUDS WILL CONTINUE TO EXPAND ACROSS THE AREA THIS MORNING...
WITH POSSIBLY A FEW PATCHES OF FOG ALSO DEVELOPING. EXPECT CLOUDS TO
BREAK UP IN MOST AREAS BY MID DAY. TEMPS WILL BE GRADUALLY WARMING
THE NEXT COUPLE OF DAYS. ONLY MINOR CHANGES MADE TO EXTENDED
PERIODS... WITH NEXT CHANCE OF PCPN ON MONDAY AND TUESDAY.

FCSTID = 32
OKC   80  62  82  63 /  10  20  10  10
HBR   82  61  86  62 /  10  20  10  10
SPS   84  64  88  64 /  20  20  10  10
GAG   82  59  87  59 /   0  10  10  10
PNC   81  62  83  63 /  10  20  10  10
DUA   80  63  82  63 /  30  30  10  10

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

OKZ004>048-050>052-TXZ083>090-031830-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
637 AM CDT THU MAY 5 2000

THE THUNDERSTORM OUTLOOK CALLS FOR A SLIGHT RISK OF SEVERE
THUNDERSTORMS TODAY ACROSS WESTERN NORTH TEXAS...AND A SMALL PART OF
SOUTH CENTRAL AND SOUTHEAST OKLAHOMA. THE RISK AREA IS SOUTH OF A
LINE FROM QUANAH TO GRANDFIELD TO WAURIKA TO ARDMORE AND CADDO.

DISCUSSION...SOUTHERLY WINDS WILL INCREASE TODAY AS LOW PRESSURE
DEVELOPS OVER THE NORTHERN PLAINS.  THIS WILL HELP TRANSPORT
DEWPOINTS IN THE MID AND UPPER 60S OVER SOUTH TEXAS INTO THE RED
RIVER VALLEY BY EARLY AFTERNOON.  INSTABILITY WILL INCREASE THIS
AFTERNOON AS TEMPERATURES WARM INTO THE LOW TO MID 80S.  THUNDERSTORMS
ARE EXPECTED TO DEVELOP ALONG AND CLOSE TO A WEAK FRONTAL BOUNDARY
ACROSS NORTH TEXAS THIS AFTERNOON.  AN UPPER LEVEL LOW LOCATED OVER
FAR EASTERN OKLAHOMA WILL ALSO AID IN THUNDERSTORM DEVELOPMENT...
ESPECIALLY ACROSS SOUTHEAST OKLAHOMA.  VERTICAL WIND PROFILES WILL
BE FAVORABLE FOR SUPERCELL DEVELOPMENT...WITH THE PRIMARY THREAT
BEING LARGE HAIL AND DAMAGING WINDS. ELEVATED THUNDERSTORMS OVER
WESTERN NORTH TEXAS THIS MORNING WILL BE CAPABLE OF PRODUCING HAIL
TO THE SIZE OF DIMES.  HOWEVER...THIS ACTIVITY IS EXPECTED TO
DIMINISH DURING THE MORNING AS LOW LEVEL WINDS WEAKEN.

EMERGENCY MANAGERS IN THE OUTLOOK AREA SHOULD PREPARE FOR POSSIBLE
SEVERE WEATHER ACTIVATION THIS AFTERNOxON.

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