[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 230113
SWODY1
SPC AC 230111

DAY 1 CONVECTIVE OUTLOOK RESENT 1
NWS STORM PREDICTION CENTER NORMAN OK
0811 PM CDT SAT APR 22 2006

VALID 230100Z - 231200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF ERN NM AND FAR
WEST TX...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF ERN LOWER
MICHIGAN...

...ERN NM/WEST TX...
WATER VAPOR IMAGERY CURRENTLY SHOWS A SHORTWAVE TROUGH EMBEDDED IN
SOUTHWEST FLOW MOVING INTO WEST TX ATTM. LARGE-SCALE ASCENT
ASSOCIATED WITH THE SHORTWAVE IS SUPPORTING A BROKEN LINE OF STORMS
EXTENDING SWD FROM NEAR TUCUMCARI NM TO MIDLAND TX. THIS LINE SHOULD
MOVE GRADUALLY EWD INTO WEST TX THROUGH THIS EVENING WHERE AN AXIS
OF MODERATE INSTABILITY EXISTS.

FORECAST SOUNDINGS THIS EVENING IN WEST TX SHOW 0-6 KM SHEAR VALUES
IN THE 30 TO 40 KT RANGE. THIS COMBINED WITH THE MODERATE
INSTABILITY AND STEEP MID-LEVEL LAPSE RATES WILL BE SUPPORTIVE OF
SUPERCELLS WITH LARGE HAIL. IN ADDITION...STEEP LOW-LEVEL LAPSE
RATES AND LARGE TEMP-DEWPOINT SPREAD MAY ENHANCE THE POTENTIAL FOR
ISOLATED WIND DAMAGE WITH THE STRONGEST STORMS. HOWEVER...THE SEVERE
THREAT SHOULD GRADUALLY DIMINISH AS THE SHORTWAVE TROUGH MOVES EWD
AND INSTABILITY WEAKENS ACROSS THE REGION.

...ERN LOWER MI...
WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL LOW OVER LAKE
MICHIGAN. STRONG LARGE-SCALE ASCENT...STEEP MID-LEVEL LAPSE RATES
AND COLD TEMPS ALOFT ARE SUPPORTING SCATTERED STRONG THUNDERSTORMS
CAPABLE OF PRODUCING LARGE HAIL. THE HAIL THREAT SHOULD CONTINUE FOR
MUCH OF THE EVENING BEFORE THE CONVECTION WEAKENS AS SFC TEMPS COOL
AND STABILIZATION OCCURS.

...ATLANTIC COASTAL PLAINS...
AN UPPER-LEVEL TROUGH IS CURRENTLY MOVING EWD ACROSS THE ATLANTIC
COASTAL STATES. LARGE-SCALE ASCENT AHEAD OF THE TROUGH IS SUPPORTING
A LINE OF THUNDERSTORMS FROM ERN NC EXTENDING SSWWD ACROSS SC AND SE
GA. INSTABILITY HAS WEAKENED OVER THE LAST FEW HOURS DUE TO OUTFLOW
FROM THE ACTIVITY. THIS COMBINED WITH 0-6 KM SHEAR VALUES AROUND 30
KT SUGGEST INSTABILITY/SHEAR PROFILES ARE MARGINAL FOR SEVERE
STORMS. ANY MARGINAL SEVERE THREAT WILL LIKELY DIMINISH THIS EVENING
AS THE LINE OF STORMS GRADUALLY MOVES OFFSHORE.

...CNTRL PLAINS AND OZARKS...
AN UPPER-LEVEL RIDGE IS CURRENTLY MOVING SLOWLY EWD ACROSS THE CNTRL
PLAINS EVIDENT ON WATER VAPOR IMAGERY. ALTHOUGH THIS IS PROVIDING
WEAK LARGE-SCALE ASCENT ACROSS THE REGION...SCATTERED THUNDERSTORMS
ARE ONGOING IN SCNTRL MO DUE TO SFC HEATING AND LOW-LEVEL
CONVERGENCE ALONG A STATIONARY FRONTAL BOUNDARY. INSTABILITY AND
SHEAR PROFILES APPEAR SUFFICIENT FOR A MARGINAL SEVERE THREAT BUT
THE CONVECTION SHOULD GRADUALLY WEAKEN AS SFC TEMPS COOL THIS
EVENING.

FURTHER WEST ACROSS KS...A 50 KT LOW-LEVEL JET IS FORECAST TO
INCREASE AND EXPAND ACROSS THE REGION TONIGHT. ISENTROPIC LIFT AND
THE INSTABILITY IN PLACE SHOULD BE SUFFICIENT FOR THE DEVELOPMENT OF
SCATTERED THUNDERSTORMS ACROSS THE ERN HALF OF KS AROUND MIDNIGHT.
FORECAST SOUNDINGS IN ECNTRL KS TONIGHT SHOW STRONG VERTICAL SHEAR
PROFILES...STEEP MID-LEVEL LAPSE RATES AND ENOUGH INSTABILITY ABOVE
700 MB FOR A MARGINAL SEVERE THREAT. HAIL WOULD BE THE MOST LIKELY
THREAT WITH ANY ELEVATED SUPERCELL STORMS THAT DEVELOP.

..BROYLES.. 04/23/2006