SPC AC 171722
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1222 PM CDT SUN OCT 17 2010
VALID 181200Z - 191200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
A BROAD UPPER TROUGH WILL STRETCH FROM THE NRN PLAINS EWD ACROSS THE
GREAT LAKES AND INTO NEW ENGLAND WITH MULTIPLE EMBEDDED SHORTWAVE
TROUGHS. THE PRIMARY TROUGH OF INTEREST WILL MOVE FROM THE NRN
PLAINS INTO THE UPPER MS VALLEY/MID MO VALLEY BY 00Z TUE. AT THE
SURFACE...HIGH PRESSURE WILL BUILD SWD ACROSS THE NRN AND CNTRL
PLAINS BEHIND A COLD FRONT THAT BY 00Z WILL EXTEND FROM NERN NM EWD
TO THE KS/OK BORDER...BECOMING MORE DIFFUSE INTO THE OH VALLEY. A
WEAK AREA OF LOW PRESSURE WILL DEVELOP OVER THE TX S PLAINS...WITH
TROUGH EXTENDING EWD PRECEDING THE COLD FRONT. SLY SURFACE FLOW WILL
EXIST ACROSS THE SRN PLAINS AROUND WRN PERIPHERY OF SERN SFC
RIDGE...WITH BOUNDARY LAYER DEWPOINTS REACHING THE LOW TO MID 50S.
TO THE W...AN UPPER LOW IS FORECAST TO SINK SWD OFF THE SRN CA COAST
WITH ONLY A WEAK AREA OF LOW PRESSURE ACROSS THE SWRN STATES.
PRESENCE OF RELATIVELY COOL AIR ALOFT AS WELL AS AMPLE MID LEVEL
MOISTURE WILL LEAD TO WEAK INSTABILITY AND SCATTERED THUNDERSTORMS
FROM PORTIONS OF SRN CA INTO THE FOUR CORNERS AREA.
...SRN KS/NRN OK...
ALTHOUGH THE WARM SECTOR WILL REMAIN CAPPED FOR SURFACE BASED
CONVECTION MOST OF THE DAY...INCREASING FRONTOGENETICAL FORCING
ALONG AND JUST N OF THE COLD FRONT SHOULD LEAD TO AN INCREASE IN
THUNDERSTORMS FROM FAR NRN OK INTO SRN AND SERN KS FROM
00-06Z...SPREADING SWD ACROSS OK OVERNIGHT. GIVEN STEEP MID LEVEL
LAPSE RATES IN PLACE...SOME OF THE STRONGER CORES MAY CONTAIN
HAIL...BUT SEVERE CRITERIA IS NOT LIKELY TO BE MET AS DEEP LAYER
SHEAR WILL BE MARGINAL ALONG WITH THE MOISTURE.
...LAKE SUPERIOR/HURON REGION THIS EVENING AND TONIGHT...
UPPER HEIGHT FALLS WILL PERSIST DURING THE OVERNIGHT HOURS WITH VERY
COOL AIR ALOFT OVERSPREADING THE AREA WITH 700 MB TEMPERATURES
DROPPING TO -12 C. GIVEN LAKE TEMPERATURES OF 10 TO 13 C...THIS WILL
PRODUCE RELATIVELY LARGE LOW LEVEL BUOYANCY WITH LAKE ENHANCED
THUNDERSTORMS LIKELY. SOME OF THE CELLS COULD PRODUCE LARGE GRAUPEL
OR SMALL HAIL POSSIBLY AFFECTING THE ERN MI U.P. OR FAR NRN LOWER
MI.
..JEWELL.. 10/17/2010
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0600Z
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