[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 270522
SWODY1
SPC AC 270520

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1220 AM CDT THU JUL 27 2006

VALID 271200Z - 281200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MID MS
VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS OVER NORTHERN NEW ENGLAND...

...THERE IS A SLGT RISK OF SVR TSTMS IN AZ...

...SYNOPSIS...
A SERIES OF WEAK UPPER IMPULSES WILL MOVE THROUGH A BROAD UPPER
TROUGH EXTENDING FROM THE NRN ROCKIES SEWD INTO THE OH VALLEY AND
THEN NEWD INTO NEW ENGLAND. A WEAK TROPICAL SYSTEM OVER ERN TX IS
EXPECTED TO LIFT NNEWD DURING THE PERIOD AND EVENTUALLY BECOME
ABSORBED INTO THE UPPER TROUGH ACROSS THE MID MS VALLEY.

...MID MS VALLEY REGION...
DEVELOPMENT OF SEVERE CONVECTION ONCE AGAIN WILL BE PROBLEMATIC AS
TIMING OF SHORTWAVE TROUGHS AND MARGINAL SHEAR EXISTS FOR SEVERE
STORMS. CURRENTLY THINKING IS SHORTWAVE TROUGH...LOCATED IN THE WRN
DAKOTAS...WILL MOVE THROUGH ERN IA AT PEAK HEATING. THE LIFT FROM
THIS SYSTEM PLUS THE FORECAST OF A REMNANT FRONT/BOUNDARY STRETCHING
FROM NRN MO EWD INTO NRN IND IS EXPECTED TO PROVIDE THE FOCUS FOR
STRONG/SEVERE CONVECTIVE DEVELOPMENT. A VERY MOIST BOUNDARY LAYER
AND TEMPERATURES WARMING TO AT LEAST 90F WILL RESULT IN A UNSTABLE
AIR MASS OVER MUCH OF THIS REGION. THE AMOUNT OF INSTABILITY AND 25
KT EFFECTIVE SHEAR SHOULD BE SUFFICIENT FOR SEVERE MULTICELL
CLUSTERS. THE STORMS WOULD LIKELY WEAKEN TO MOSTLY BELOW SEVERE
CRITERIA BY MID EVENING SINCE THE STORMS WILL BE PRIMARILY
THERMODYNAMICALLY DRIVEN.

...NRN NEW ENGLAND...
PRONOUNCED SHORTWAVE TROUGH...CURRENTLY MOVING THROUGH THE ERN GREAT
LAKES REGION...WILL MOVE ACROSS NRN NEW ENGLAND DURING THE HEAT OF
THE DAY. MID LEVEL WINDS ARE FORECAST TO INCREASE TO NEAR 30 KT WITH
UNIDIRECTIONAL SWLY WINDS ABOVE THE BOUNDARY LAYER. THIS SHOULD
PROVIDE A FAVORABLE ENVIRONMENT FOR BANDS/LINES OF STORMS TO
DEVELOP. ALTHOUGH THE INSTABILITY WILL NOT BE PARTICULARLY
STRONG...MID LEVEL LAPSE RATES WILL BE STEEPER THAN NORMAL...AROUND
7.5 C/KM. THE SHEAR IN COMBINATION WITH THE LARGE SCALE FORCING AND
STEEP LAPSE RATES SHOULD FAVOR A FEW SEVERE WIND AND HAIL EVENTS
DURING THE AFTERNOON/EARLY EVENING HOURS.

..AZ...
RICH LOW LEVEL MOISTURE WILL AGAIN BE IN PLACE OVER MUCH OF THE AREA
THURSDAY...SUPPORTING MODERATE TO STRONG INSTABILITY. THE MID LEVEL
NLY WINDS ARE FORECAST TO STRENGTHEN AS THE UPPER HIGH SHIFTS NWD
THROUGH NV. A SHORTWAVE TROUGH IN ERN UT IS ALSO EXPECTED TO ROTATE
AROUND THE HIGH AND INTO NERN AZ DURING THE AFTERNOON. THE STRONGER
MID/HIGH LEVEL WINDS WILL HELP TO MOVE CONVECTION/CLOUDS SWD OUT OF
THE STATE THIS MORNING. ALTHOUGH THE HEATING LIKELY WILL NOT BE AS
STRONG AS THE PAST SEVERAL DAYS... ONCE THE STORMS DEVELOP OVER THE
HIGHER TERRAIN...THE STRONGER WINDS/SHEAR SHOULD CARRY THEM SWD INTO
THE DESERT FLOORS WITH A THREAT FOR SEVERE WINDS AND PERHAPS SOME
HAIL.

...NRN OH/WRN NY...
WRF MODEL SUGGESTS THAT THE LAKE BREEZE WILL BECOME CONVECTIVELY
ACTIVE DURING THE AFTERNOON. THE DEEP LAYER SHEAR WILL BE MARGINAL
FOR SEVERE...BUT UNDIRECTIONAL WLY WINDS AND MLCAPE VALUES FROM 
1500-2000 J/KG WOULD SUPPORT STRONG WIND GUSTS.

...KS...
MID/HIGH LEVEL MOISTURE FROM THE MONSOONAL FLOW WILL SPREAD NEWD
ACROSS KS AND HELP IN THE INITIATION OF LATE AFTERNOON
THUNDERSTORMS. HOT TEMPERATURES AND STEEP LOW LEVEL LAPSE RATES MAY
SUPPORT SOME STRONG/SEVERE WIND GUSTS.

..IMY/TAYLOR.. 07/27/2006