[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 040100
SWODY1
SPC AC 040058

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0758 PM CDT WED MAY 03 2006

VALID 040100Z - 041200Z

...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM PARTS OF THE SRN
PLAINS INTO THE OZARK PLATEAU....

CLOSED LOW WILL BEGIN TO GRADUALLY LIFT AWAY FROM THE NORTHERN
MINNESOTA BORDER AREA OVERNIGHT...BUT BELT OF STRONG MID/UPPER FLOW
WILL PERSIST IN BASE OF BROADER SCALE TROUGH ALONG THE CENTRAL
U.S./CANADIAN BORDER.  UPSTREAM...ANOTHER CLOSED LOW APPEARS TO BE
EVOLVING ACROSS PARTS OF CALIFORNIA/THE INTERMOUNTAIN WEST...IN A
MORE SOUTHERN BRANCH OF WESTERLIES...AS A SIGNIFICANT EMBEDDED JET
STREAK DIGS OFF THE CALIFORNIA COAST.  AHEAD OF THIS FEATURE...A
STRONG SUBTROPICAL STREAM IMPULSE/JET STREAK IS NOSING INTO THE
SOUTHWESTERN U.S./MEXICO BORDER AREA.

...SOUTHERN PLAINS INTO THE OZARKS...
SURFACE RIDGE CONTINUES TO NOSE THROUGH THE CENTRAL PLAINS BENEATH
CONFLUENT BELTS OF WESTERLIES. ASSOCIATED SURFACE FRONT IS NOW
ADVANCING THROUGH THE OZARKS/NORTHERN OKLAHOMA AND THE
TEXAS/OKLAHOMA PANHANDLE REGION...BUT CONVECTIVE DEVELOPMENT HAS
BEEN SPARSE IN COVERAGE...LIMITED TO DISTINCT AREAS OF STRONGER
MID/UPPER FORCING.

ONE OF THESE AREAS IS CURRENTLY OVER THE MISSOURI OZARKS...WHERE
WEAK SOUTHERN BRANCH PERTURBATION...PERHAPS CONVECTIVELY INDUCED...
HAS AIDED ANOTHER SMALL CONVECTIVE CLUSTER.  AS STRONGER MID/UPPER
FORCING CONTINUES EASTWARD ACROSS THE MIDDLE MISSISSIPPI
VALLEY...INTO ENVIRONMENT SUBSTANTIALLY MODIFIED BY EARLIER
CONVECTION...A GRADUAL WEAKENING TREND IS EXPECTED THROUGH LATE
EVENING.

PRIMARY CONVECTIVE DEVELOPMENT SEEMS LIKELY TO PROCEED ACROSS PARTS
OF WEST CENTRAL/NORTHWEST TEXAS INTO THE RED RIVER VALLEY.  ONGOING
CONVECTIVE CLUSTER EVOLVING NEAR/SOUTHEAST OF LUBBOCK SEEMS LIKELY
TO BE SUPPORTED BY MOIST INFLOW OF 40 KT SOUTHERLY LOW-LEVEL JET
DEVELOPING ACROSS WESTERN TEXAS.  LARGE-SCALE ASCENT WILL BE
ENHANCED BY STRENGTHENING DIVERGENCE ASSOCIATED WITH COUPLED
SUBTROPICAL AND POLAR JETS...AND SUBSTANTIAL EXPANSION OF CONVECTIVE
CLUSTER IS EXPECTED THROUGH 06Z.  MID-LEVEL FLOW IS GENERALLY
WEAK...BUT LARGE CAPE WILL REMAIN SUPPORTIVE OF HAIL POTENTIAL...AND
RELATIVE HUMIDITIES ARE LOW ENOUGH TO SUPPORT ISOLATED
DOWNBURSTS...POSSIBLY THE EVOLUTION OF ONE OR MORE COLD POOLS WITH
STRONG GUSTY WINDS.

...TENNESSEE VALLEY...
WEAK FLOW REGIME AND STABILIZING LOW-LEVEL ENVIRONMENT SUGGEST ANY
FURTHER SEVERE THREAT WITH ONGOING CONVECTIVE CLUSTER WILL BE SHORT
LIVED. STORMS SHOULD WEAKEN THIS EVENING AS THEY PROGRESS ACROSS
MIDDLE TENNESSEE INTO THE SOUTHERN APPALACHIANS.

..KERR.. 05/04/2006