[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 190558
SWODY2
SPC AC 190557

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1257 AM CDT FRI MAY 19 2006

VALID 201200Z - 211200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN KS/MO SEWD INTO THE
SRN PORTION OF THE TN VALLEY...

...SYNOPSIS...
OVERALL PATTERN WILL CHANGE LITTLE WITH HIGHLY AMPLIFIED TROUGH
REMAINING ACROSS THE WEST AND A STRONG TROUGH LOCATED ACROSS THE
NERN QUARTER OF THE COUNTRY. THE PAST FEW MODEL RUNS HAVE EVOLVED TO
A STRONGER SHORTWAVE TROUGH/JET MAX/COLD FRONT SHIFTING FROM THE WRN
GREAT LAKES INTO NY DURING THE PERIOD. THE REMNANTS OF A WEAK FRONT
ARE FORECAST TO STRETCH FROM SRN KS ESEWD INTO THE SRN PORTION OF
THE TN VALLEY AND THEN EWD INTO THE CAROLINAS. BETWEEN THE TWO UPPER
TROUGHS...MID/HIGH LEVEL MOISTURE...TRAPPED BENEATH UPPER RIDGE OVER
THE ROCKIES...COMBINED WITH DAYTIME HEATING WILL RESULT IN SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS ACROSS THE HIGHER TERRAIN.

...ERN KS/MO SEWD ACROSS NRN AR AND INTO THE SRN TN VALLEY AREA...
A MOSTLY NON SEVERE MCS IS EXPECTED TO BE MOVING THROUGH THE
CAROLINAS EARLY IN THE PERIOD...AS ASSOCIATED SPEED MAX MOVES
OFFSHORE. ONCE THESE STORMS MOVE OFFSHORE...UNCERTAINTY EXISTS WHEN
AND WHERE MORE STORMS WILL REDEVELOP. ALTHOUGH FRONT IS FORECAST TO
REMAIN NEARLY QUASI-STATIONARY THROUGH THE DAY...500 MB HEIGHTS ARE
PROGGED TO RISE SLIGHTLY. NO SHORTWAVE TROUGHS ARE EVIDENT WITHIN
30-40 KT NWLY FLOW MID LEVEL FLOW...THOUGH VEERING WIND PROFILES
WOULD PROVIDE FAVORABLE SHEAR FOR SEVERE STORMS. ALTHOUGH MODEL
FORECAST OF MID TO UPPER 60S DEWPOINTS APPEARS TO BE
OVERESTIMATED...SURFACE DEWPOINTS NEAR 60F AND 850-500 MB LAPSE
RATES AROUND 7.5 C/KM SHOULD YIELD AFTERNOON MLCAPES FROM 2000-2500
J/KG. VERY WARM TEMPERATURES AND DRY AIR BETWEEN 700-850 MB SHOULD
INHIBIT CONVECTION SOUTH AND WEST OF FRONT. HOWEVER ANY FORCING ON
THE COOL SIDE OF THE FRONT MAY PROVIDE ENOUGH LIFT FOR PARCELS TO
REACH THE LFC. IF STORMS DO DEVELOP...THE SHEAR AND DEGREE OF
INSTABILITY WOULD SUPPORT STORMS WITH SEVERE HAIL AND DAMAGING
WINDS.

...WI...
THOUGH SLIGHT DIFFERENCES EXIST IN TIMING OF SHORTWAVE TROUGH/
SPEED MAX...MODELS SUGGEST STRONG FORCING/COLD FRONT WILL MOVE
ACROSS WI AROUND EARLY/MID AFTERNOON. THE STRENGTH OF THIS SYSTEM
AND VERY STRONG VERTICAL WIND PROFILES APPEAR SUPPORTIVE OF A SEVERE
STORM THREAT. THE ONLY QUESTION IS THE LIMITED AMOUNT OF MOISTURE IN
BOUNDARY LAYER SINCE RETURN OF RICHER GULF MOISTURE WILL BE CONFINED
TO THE GULF COASTAL STATES. HOWEVER...A HIGHER RISK FOR SEVERE
WEATHER WOULD BE NEEDED IF THE BOUNDARY LAYER MOISTENS MORE THAN
CURRENTLY EXPECTED.

...NRN ID AND WRN MT...
EMBEDDED SHORTWAVE TROUGHS MOVING NEWD WITHIN 40-50 KT MID LEVEL
FLOW MAY RESULT IN A FEW STORMS WITH A POTENTIAL FOR BRIEF STRONG
WIND GUSTS DURING THE AFTERNOON/EVENING HOURS.

..IMY.. 05/19/2006