Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 010425
SWODY2
SPC AC 010424

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1124 PM CDT TUE SEP 30 2014

VALID 021200Z - 031200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDWEST TO CNTRL TX...

...SUMMARY...
BAND OF THUNDERSTORMS SHOULD FORM ALONG COLD FRONT AS IT PROGRESSES
ACROSS THE PLAINS INTO THE MISSISSIPPI VALLEY.  DAMAGING WIND GUSTS
ARE THE PRIMARY SEVERE THREAT WITH THE STRONGEST STORMS.

...MIDWEST TO CNTRL TX...

LOW LATITUDE SHORT-WAVE TROUGH WILL EJECT ACROSS THE SRN
ROCKIES/HIGH PLAINS EARLY IN THE PERIOD BEFORE EJECTING RAPIDLY NEWD
INTO THE LOWER OH VALLEY AFTER MIDNIGHT.  PRIMARY FEATURE
RESPONSIBLE FOR THIS RAPID EJECTION IS AN INTENSIFYING SPEED MAX
THAT WILL DIG INTO THE CNTRL PLAINS BY 03/12Z.  THIS SECONDARY
FEATURE SHOULD AID DEEPENING CYCLONE/SHARPENING FRONTAL BOUNDARY
OVER THE UPPER GREAT LAKES LATE.

ALTHOUGH FRONTAL INTENSIFICATION IS NOT EXPECTED UNTIL LATE IN THE
PERIOD...CONVECTION IS EXPECTED TO DEVELOP ALONG PROGRESSIVE
BOUNDARY BEGINNING FAIRLY EARLY IN THE PERIOD.  LATEST MODEL
GUIDANCE SUGGEST AMPLE BOUNDARY LAYER MOISTURE WILL ADVANCE AS FAR
NORTH AS NRN IL BY LATE AFTERNOON WITH PW VALUES AOA 1.5 INCHES.
WHAT LITTLE CINH IS OBSERVED AT 12Z AHEAD OF THE FRONT WILL DIMINISH
BY 17-18Z SUCH THAT THUNDERSTORMS SHOULD READILY DEVELOP ALONG WIND
SHIFT ACROSS ERN KS/OK.  THIS ACTIVITY SHOULD MATURE INTO A
EXTENSIVE SQUALL LINE STRETCHING FROM THE MID MS VALLEY...SWWD INTO
NERN TX BY LATE AFTERNOON.  GREATEST BUOYANCY IS EXPECTED TO RESIDE
FROM THE OZARK PLATEAU SWWD INTO TX AND HAIL IS MOST LIKELY ALONG
THIS PORTION OF THE SQUALL LINE.  MEAN SWLY WIND WILL BE ON THE
ORDER OF 30-35KT...MORE THAN ADEQUATE FOR PROGRESSIVE SQUALL LINE
THAT SHOULD ADVANCE TOWARD THE MS RIVER DURING THE EVENING HOURS.
WHILE DEEP LAYER SHEAR IS MORE THAN ADEQUATE FOR DEEP
ROTATION...STORM MODE FAVORS LINEAR DEVELOPMENT AND DAMAGING WINDS
ARE THE PRIMARY SEVERE THREAT.

..DARROW.. 10/01/2014




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