DAY3SVR: Nws Storm Prediction Center Norman Ok

ACUS03 KWNS 190727
SWODY3
SPC AC 190726

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0226 AM CDT SUN AUG 19 2012

VALID 211200Z - 221200Z

...SYNOPSIS...
AN AMPLIFIED LARGE-SCALE UPPER-LEVEL TROUGH WILL PERSIST FROM SERN
CANADA TO THE GULF COAST...ALTHOUGH THE HEIGHT GRADIENT WILL BEGIN
TO RELAX. AN EMBEDDED SHORT WAVE IMPULSE SHOULD PROGRESS FROM THE
MIDWEST TOWARDS THE MID-ATLANTIC. A QUASI-STATIONARY FRONT WILL
REMAIN ORIENTED SW/NE FROM THE CNTRL GULF COAST TO THE MID-ATLANTIC.
IN THE NORTHWEST...A SHORT WAVE TROUGH WILL IMPINGE ON AN
UPPER-LEVEL RIDGE AND SHOULD REACH THE NRN ROCKIES/SRN CANADIAN
ROCKIES BY 12Z/WED.

...NRN ROCKIES...
AS MID-LEVEL HEIGHT FALLS AND LARGE-SCALE ASCENT OVERSPREAD THE
REGION...ISOLATED TSTMS MAY BE ONGOING TUE MORNING ALONG A PLUME OF
HIGHER PW VALUES BEING ADVECTED NWD FROM THE GREAT BASIN. TSTM
COVERAGE WILL LIKELY DIURNALLY INCREASE...BUT GUIDANCE IS FAIRLY
CONSISTENT THAT A NARROW BELT OF STRONG MID-LEVEL SWLYS WILL LARGELY
LAG THE LOBE OF LEADING ASCENT. THIS BREEDS UNCERTAINTY OVER THE
DEGREE OF JUXTAPOSITION BETWEEN STRENGTHENING DEEP-LAYER SHEAR AND
GREATER INSTABILITY. AS SUCH...WILL ONLY INTRODUCE LOW-END SEVERE
PROBABILITIES ATTM.

...SOUTH/LOWER MID-ATLANTIC COAST...
ONE MORE DAY OF MARGINAL DAMAGING WIND POTENTIAL SHOULD EXIST
DOWNSTREAM OF THE LARGE-SCALE UPPER-LEVEL TROUGH. ALTHOUGH LOW-LEVEL
FLOW WILL BE WEAK AND MID-LEVEL SWLYS SHOULD SUBSIDE SLIGHTLY
RELATIVE TO D2...ASCENT TIED TO THE SHORT WAVE IMPULSE CROSSING THE
OH VALLEY AREA ON TUE AFTERNOON SHOULD AID IN A DIURNAL INCREASE IN
TSTM COVERAGE. PRECEDING DAYS OF CONVECTION SHOULD MAINTAIN WEAK
MID-LEVEL LAPSE RATES...BUT LOCALIZED DAMAGING WINDS WILL REMAIN
POSSIBLE WHERE POCKETS OF STRONGER SURFACE HEATING OCCUR.

..GRAMS.. 08/19/2012

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.