Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 281946
SWODY1
SPC AC 281944

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0144 PM CST WED JAN 28 2015

VALID 282000Z - 291200Z

...NO TSTM AREAS FORECAST...

...SUMMARY...
THE RISK FOR THUNDERSTORMS APPEARS NEGLIGIBLE ACROSS MUCH OF THE
U.S. THIS AFTERNOON THROUGH TONIGHT.

...20Z OUTLOOK UPDATE...
THE LATEST RAPID REFRESH /18Z/ DOES INDICATE THE DEVELOPMENT OF AN
AXIS OF VERY WEAK DESTABILIZATION /BASED AROUND 700 MB/ IN A NARROW
CORRIDOR...NORTHWEST OF NASHVILLE TN THROUGH THE LOUISVILLE KY AND
CINCINNATI OH AREAS...TOWARD 29/11-12Z.  THIS LIKELY IS IN RESPONSE
TO MID-LEVEL MOISTENING AND LARGE-SCALE ASCENT AHEAD OF THE SHORT
WAVE TROUGH OF SUBTROPICAL EASTERN PACIFIC ORIGIN...CURRENTLY
TURNING EAST SOUTHEAST OF THE FRONT RANGE OF THE ROCKIES.  WHILE THE
ASSOCIATED RAPID REFRESH FORECAST SOUNDINGS SUGGEST IT MAY NOT BE
COMPLETELY OUT OF THE QUESTION THAT THIS COULD BECOME SUPPORTIVE OF
WEAK THUNDERSTORM ACTIVITY... AT THE PRESENT TIME PROBABILITIES FOR
THUNDER STILL SEEM BELOW THE MINIMUM 10 PERCENT THRESHOLD FOR A
CATEGORICAL THUNDER AREA.

..KERR.. 01/28/2015

.PREV DISCUSSION... /ISSUED 1018 AM CST WED JAN 28 2015/

...SYNOPTIC SETUP/FORECAST...
MULTI-STREAM...LARGELY CYCLONIC FLOW WILL PREVAIL OVER THE CONUS
THROUGH EARLY THU...IN WAKE OF DEPARTING E CST TROUGH. SHORTWAVE
IMPULSE THAT CROSSED THE GRT BASIN YESTERDAY WILL TRACK ESE INTO THE
MID MS VLY BY THE END OF THE PERIOD AS NRN STREAM IMPULSE NOW OVER
AB/SK CONTINUES ESE TO MN/WI. IN RESPONSE...EXPECT EXISTING LEE LOW
TO CONSOLIDATE ESEWD...WITH THE MAIN CIRCULATION CENTER NEARING CHI
BY 12Z THU.

A PLUME OF STEEP MID-LVL LAPSE RATES WILL SWEEP E/NE INTO THE LWR OH
VLY EARLY THU AHEAD OF LEAD UPR SYSTEM...AND ATOP STRENGTHENING WAA
ZONE E OF ASSOCIATED SFC LOW. WHILE INCREASING HIGH AND MID-LVL
CONVECTION LIKELY WILL ARISE IN THIS ENVIRONMENT...ESPECIALLY IN
CORRIDOR OF GREATEST DVCA OVER IL...SPARSE MOISTURE SUGGESTS THAT
BUOYANCY/CHARGE SEPARATION WILL REMAIN TOO FEEBLE FOR THUNDER.




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