[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 011625
SWODY1
SPC AC 011623

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1123 AM CDT SUN OCT 01 2006

VALID 011630Z - 021200Z

...NO SVR TSTM AREAS FORECAST...

...NORTHEAST STATES...
LARGE UPPER TROUGH CONTINUES TO TRACK EASTWARD ACROSS THE NORTHEAST
U.S. THIS MORNING...WHILE UPPER RIDGING DEVELOPS ACROSS THE PLAINS
STATES.  THE PRIMARY BAROCLINIC ZONE ASSOCIATED WITH THE EASTERN
TROUGH IS MOVING EASTWARD ACROSS EASTERN NY.  STRONG LOW LEVEL WARM
ADVECTION AND FORCING ARE PRODUCING WIDESPREAD PRECIPITATION AND
CLOUDS THROUGHOUT SOUTHERN/CENTRAL NEW ENGLAND.  VERY LIMITED LAPSE
RATES AND CAPE VALUES SUGGEST THAT SEVERE THREAT IS LOW...DESPITE
IMPRESSIVE LOW LEVEL AND DEEP LAYER VERTICAL SHEAR PROFILES.  THERE
REMAINS A SMALL AREA FROM RI INTO EASTERN MA WHERE SUFFICIENT LOW
LEVEL INSTABILITY COULD RESULT IN LOCALLY DAMAGING WIND GUSTS. 
HOWEVER...THE THREAT AREA HAS BECOME QUITE SMALL AND SHOULD END BY
MID AFTERNOON AS CONVECTIVE LINE MOVES OFFSHORE.

IN THE WAKE OF THIS ACTIVITY...CLEARING SKIES WILL ALLOW STRONG
HEATING FROM THE NYC AREA WESTWARD INTO PARTS OF EASTERN PA/NJ INTO
THE DELMARVA.  LOW LEVEL COLD/DRY ADVECTION SHOULD MINIMIZE DEEP
CONVECTIVE THREAT.  HOWEVER...SOME MODEL GUIDANCE MAINTAINS A RISK
OF LOW-TOPPED AFTERNOON SHOWERS/THUNDERSTORMS ACROSS THIS REGION. 
IF STORMS CAN FORM...COLD THERMODYNAMIC PROFILES WOULD BE FAVORABLE
FOR HAIL.  THEREFORE...WILL MAINTAIN LOW PROBABILITIES.

...WI/IL...
UPPER RIDGING IS OCCURRING ACROSS THE MIDWEST TODAY...ATOP RATHER
DRY/STABLE CONDITIONS. STRONG LOW LEVEL WARM/MOIST ADVECTION WILL
OCCUR THROUGH TONIGHT RESULTING IN MARGINAL ELEVATED INSTABILITY BY
THIS EVENING.  MODEL FORECAST SOUNDINGS SUGGEST THAT UNSTABLE LEVEL
WILL BE ROOTED ABOVE 700MB...AND WILL YIELD CAPE VALUES BELOW 500
J/KG.  GIVEN THIS SCENARIO...IT APPEARS LIKELY THAT OVERNIGHT
CONVECTION THAT MAY DEVELOP IN THIS REGION WILL PROBABLY BE
NON-SEVERE.

..HART/GRAMS.. 10/01/2006