SPC AC 181730
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1230 PM CDT SUN JUL 18 2010
VALID 191200Z - 201200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MIDDLE MO
VALLEY/MIDWEST/OH VALLEY...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHEAST
STATES/SOUTHERN NEW ENGLAND...
...SYNOPSIS...
LITTLE FLUCTUATION OF THE LARGE SCALE PATTERN WILL OCCUR INTO
MONDAY...WITH SEASONALLY FAST LOW AMPLITUDE WESTERLIES PREVALENT
OVER THE NORTHERN TIER OF THE CONUS TO CANADA...WHILE UPPER RIDGING
PREVAILS OVER THE SOUTHERN TIER WITH THE BRUNT OF THE ANTICYCLONE
REMAINING CENTERED OVER THE FOUR CORNERS VICINITY.
...MIDDLE MO VALLEY/MIDWEST/OH VALLEY...
SCATTERED STRONG STORMS/PERHAPS EVEN A LOOSELY ORGANIZED MCS WILL
LIKELY BE ONGOING MONDAY MORNING...MOST LIKELY ACROSS EASTERN
NEB/SOUTHEAST SD TO WESTERN IA...ON THE NOSE OF A MODERATELY STRONG
SOUTHWESTERLY LOW LEVEL JET/ASSOCIATED MOISTURE TRANSPORT REGIME.
WHILE THESE EARLY DAY STORMS MAY WEAKEN/ONLY POSE A LIMITED SEVERE
THREAT...AN UPSWING IN DEEP CONVECTION IS PROBABLE MONDAY
AFTERNOON...AIDED BY A LOW AMPLITUDE SHORTWAVE TROUGH/SUBTLE SPEED
MAX. THIS WILL MOST LIKELY BE QUASI-FOCUSED ALONG A WNW-ESE ORIENTED
FRONTAL ZONE ACROSS THE MIDWEST TO THE LOWER OH VALLEY...INCLUDING
PORTIONS OF IA AND NORTHEAST MO INTO IL...WITH ADDITIONAL
DEVELOPMENT POSSIBLE ALONG THE RETREATING EFFECTIVE FRONTAL ZONE
ACROSS THE LOWER OH VALLEY VICINITY. THIS CORRIDOR WILL LIKELY
BECOME MODERATELY TO STRONGLY UNSTABLE BY AFTERNOON...WITH THE
PREVALENCE OF LOWER TO MIDDLE 70S F SURFACE DEWPOINTS SUPPORTIVE OF
MLCAPES TO UPWARDS OF 2500-4000 J/KG.
OVERALL...WITH RELATIVELY STRONG MID LEVEL/DEEP TROPOSPHERIC FLOW
JUXTAPOSED WITH THE AFOREMENTIONED SURFACE FRONTAL ZONE...EARLY
MODAL SUPERCELLS /MAINLY IA AND NORTHEAST MO TO IL/ ALONG WITH
WELL-ORGANIZED MULTICELLS/EAST-SOUTHEASTWARD MOVING LINEAR CLUSTERS
SHOULD BE COMMON. DAMAGING WINDS WILL BE THE PRIMARY CONCERN...WITH
SOME SEVERE HAIL AND PERHAPS A TORNADO POSSIBLE AS WELL. STORMS MAY
GROW UPSCALE/CONTINUE TO POSE A DAMAGING WIND THREAT MONDAY NIGHT AS
THEY STEADILY PROGRESS EASTWARD ACROSS PORTIONS OF IL/INDIANA AND
PERHAPS OH.
...NORTHEAST STATES/NEW ENGLAND TO MID ATLANTIC STATES...
IN ASSOCIATION WITH A CYCLONIC UPPER FLOW REGIME...A SURFACE LOW IS
EXPECTED TO ADVANCE EAST-NORTHEASTWARD ACROSS NORTHERN NEW ENGLAND
ON MONDAY...WITH AN EASTWARD MOVING COLD FRONT SERVING AS A FOCUS
FOR STRONG/SEVERE TSTM DEVELOPMENT DURING THE DAY. CLOUD/COVER
PRECIPITATION ALONG/JUST AHEAD OF THE AFOREMENTIONED FRONT MAY LIMIT
APPRECIABLE DESTABILIZATION...BUT MLCAPES POTENTIALLY TO 1000-1500
J/KG...IN CONJUNCTION WITH GENERALLY 30-40 KT MID LEVEL WESTERLY
FLOW...WILL SUPPORT THE DEVELOPMENT OF SUSTAINED MULTICELLS/LINEAR
CLUSTERS CAPABLE OF MAINLY DAMAGING WINDS.
..GUYER.. 07/18/2010
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
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