691
ACUS03 KWNS 120731
SWODY3
SPC AC 120730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT MON AUG 12 2013
VALID 141200Z - 151200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
A HIGHLY AMPLIFIED LONGWAVE PATTERN WILL EXIST ON WEDNESDAY.
PREVALENT TROUGHING WILL CONTINUE OVER THE EASTERN THIRD OF THE
CONUS WHILE AN UPPER RIDGE BUILDS OVER THE NORTHERN ROCKIES/HIGH
PLAINS IN ADVANCE OF AN UPPER LOW NEARING BRITISH COLUMBIA/WA COAST.
...LOWER MS VALLEY/GULF COAST TO SOUTHEAST STATES...
FRONTAL BOUNDARY WILL CONTINUE TO EFFECTIVELY SETTLE SOUTHWARD
ACROSS THE REGION ON WEDNESDAY...WHILE BROAD/WEAK GENERAL CYCLONIC
FLOW ALOFT PREVAILS. AT LEAST WIDELY SCATTERED SHOWERS/TSTMS SHOULD
BE PREVALENT RELATIVELY EARLY IN THE DAY ALONG THE FRONTAL
ZONE...BUT POCKETS OF SOMEWHAT STRONGER HEATING/MODEST
DESTABILIZATION ALONG AND ESPECIALLY SOUTH OF THIS ACTIVITY MAY
CONTRIBUTE TO LOCALIZED DOWNBURST/WIND DAMAGE POTENTIAL WEDNESDAY
AFTERNOON.
...NORTHERN HIGH PLAINS...
LEE TROUGH AND OROGRAPHIC INFLUENCES/WEAK UPSLOPE SHOULD RESULT IN
ISOLATED/WIDELY SCATTERED TSTM DEVELOPMENT WEDNESDAY AFTERNOON/EARLY
EVENING WITHIN A GENERAL NORTH-SOUTH CORRIDOR ACROSS THE HIGH PLAINS
INCLUDING EASTERN MT INTO FAR WESTERN PORTIONS OF THE
DAKOTAS/NEBRASKA. VERTICAL SHEAR WILL BE RELATIVELY WEAK /GENERALLY
25-30 KT EFFECTIVE/...BUT VEERING WIND PROFILES AND WEAK TO MODERATE
DESTABILIZATION MAY YIELD A FEW SEVERE TSTMS WITH HAIL/WIND POSSIBLE
ON A VERY ISOLATED BASIS. A WEAK WARM ADVECTION REGIME COULD SUSTAIN
TSTMS INTO PARTS OF SD/NEB THROUGH THE LATE NIGHT HOURS INTO EARLY
THURSDAY.
...SOUTHERN HIGH PLAINS TO ARKLATEX...
PENDING SUFFICIENT DESTABILIZATION...A FEW STRONG TSTMS MIGHT BE
POSSIBLE WEDNESDAY AFTERNOON ACROSS NORTH/EAST TX AND/OR THE
ARKLATEX VICINITY...BUT MUCH OF THIS WOULD DEPEND ON UNCERTAIN
MESOSCALE DETAILS INTO THE DAY 3 TIME FRAME. REGARDLESS...NOTHING
BEYOND ISOLATED DOWNBURSTS CAN BE EXPECTED.
A SOMEWHAT MORE CERTAIN SCENARIO MAY BE FOR LOW-LEVEL UPSLOPE
TRAJECTORIES TO INCREASE ACROSS THE SOUTHERN HIGH PLAINS INTO
WEDNESDAY AFTERNOON...LEADING TO DIURNALLY MAXIMIZED TSTMS ACROSS
EASTERN NM/FAR SOUTHEAST CO INTO WEST TX. SUFFICIENT SHEAR/MODEST
BUOYANCY COULD ALLOW FOR MULTICELL/PERHAPS WEAK SUPERCELL
DEVELOPMENT WITH SOME HAIL/WIND POSSIBLE.
..GUYER.. 08/12/2013