SPC AC 080559
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1259 AM CDT WED SEP 08 2010
VALID 091200Z - 101200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHERN HIGH
PLAINS...
...SYNOPSIS...
THE AMPLIFYING WESTERN STATES UPPER TROUGH IS ULTIMATELY EXPECTED TO
TRANSITION EAST-NORTHEASTWARD OVER THE GREAT BASIN/INTERMOUNTAIN
WEST AND NORTHERN/CENTRAL ROCKIES ON THURSDAY. IN RESPONSE TO THIS
SYSTEM...LEE CYCLOGENESIS/TROUGHING WILL OCCUR ACROSS THE
NORTH-CENTRAL HIGH PLAINS...WITH A MOIST AIRMASS BECOMING
INCREASINGLY REESTABLISHED NORTHWARD INTO THE NORTHERN HIGH PLAINS
ATTENDANT TO A NORTHWARD RETREATING WARM FRONT.
THE REMNANTS OF TROPICAL DEPRESSION HERMINE ARE EXPECTED TO CONTINUE
TO ADVANCE NORTHEASTWARD/GRADUALLY ACCELERATE ACROSS THE
SOUTH-CENTRAL PLAINS TO LOWER MO VALLEY/OZARKS ON THURSDAY.
...NORTHERN/CENTRAL HIGH PLAINS...
LEE CYCLOGENESIS/TROUGHING...COINCIDENT WITH A MOISTENING WARM
SECTOR...IS ANTICIPATED ACROSS THE REGION ON THURSDAY UNDER THE
INFLUENCE OF LARGE SCALE HEIGHT FALLS AHEAD OF THE APPROACHING
WESTERN STATES UPPER TROUGH. IT APPEARS THE LEADING EDGE OF
FORCING/COOLING ALOFT WILL FAVORABLY COINCIDE WITH PEAK
HEATING...SUCH THAT THE POTENTIAL FOR STRONG/SEVERE SURFACE BASED
TSTMS WILL INCREASE DURING THE LATE AFTERNOON/EVENING HOURS IN
VICINITY OF THE DEEPENING SURFACE LOW/LEE TROUGH...INCLUDING
PORTIONS OF THE WESTERN DAKOTAS/WESTERN NEB. ADDITIONAL
STRONG/SEVERE TSTMS WILL BE POSSIBLE ALONG AN INVERTED SURFACE
TROUGH AND/OR IN AN IMMEDIATE POST-SURFACE FRONTAL ENVIRONMENT
ACROSS EASTERN MT/NORTHERN WY.
AMID THE INCREASING PREVALENCE OF UPPER 50S TO LOWER 60S F SURFACE
DEWPOINTS...MODERATE DESTABILIZATION /1000-1750 J PER KG MLCAPE/ IS
EXPECTED ACROSS THE WARM SECTOR/EAST OF THE LEE TROUGH. COUPLED WITH
GRADUALLY STRENGTHENING SOUTHWESTERLY FLOW ALOFT /40-55 KT AT 500
MB/ ACROSS THE HIGH PLAINS...THIS WILL SUPPORT ORGANIZED/SUSTAINED
STORMS INCLUDING SUPERCELLS CAPABLE OF SEVERE HAIL/GUSTY WINDS AND
PERHAPS A TORNADO MAINLY DURING THE LATE AFTERNOON TO MID EVENING
HOURS.
...SOUTH-CENTRAL PLAINS TO OZARKS/LOWER MO VALLEY...
THE REMNANTS OF TROPICAL DEPRESSION HERMINE ARE EXPECTED TO
ADVANCE/PERHAPS BEGIN TO ACCELERATE NORTHEASTWARD ACROSS THE REGION
ON THURSDAY. EVEN WHILE THESE REMNANTS MAY BEGIN TO INTERACT WITH A
RETREATING FRONTAL BOUNDARY ACROSS THE LOWER MO
VALLEY/OZARKS...CONTINUED WEAKENING OF HERMINE ASSOCIATED LOW LEVEL
WIND FIELDS...IN ADDITION TO LIMITED OR AT LEAST AN UNCERTAIN DEGREE
OF DESTABILIZATION...PRECLUDE SEVERE /TORNADO/ PROBABILITIES INTO
THE DAY 2 TIME FRAME. WITH THAT SAID...IT IS CONCEIVABLE THAT A
BRIEF/LOCALIZED TORNADO THREAT MAY EXIST MAINLY THURSDAY
AFTERNOON/EVENING...AND SUCH WILL BE REEVALUATED IN SUBSEQUENT
OUTLOOKS.
..GUYER.. 09/08/2010
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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