Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 290521
SWODY2
SPC AC 290519

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1219 AM CDT FRI AUG 29 2014

VALID 301200Z - 311200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN
PLAINS...

...SUMMARY...
ISOLATED SEVERE THUNDERSTORMS ARE EXPECTED ACROSS PORTIONS OF THE
NORTHERN HIGH PLAINS.  GUSTY WINDS AND LARGE HAIL ARE THE PRIMARY
THREATS.  ELSEWHERE...SCATTERED THUNDERSTORMS SHOULD DEVELOP FROM
THE UPPER TEXAS COAST TO LOWER MICHIGAN.

...NRN PLAINS...

MODEST MID-LEVEL HEIGHT FALLS WILL SPREAD ACROSS THE NRN
INTER-MOUNTAIN REGION INTO THE HIGH PLAINS OF MT SATURDAY AHEAD OF
SIGNIFICANT TROUGH THAT WILL ADVANCE TO A POSITION FROM ID INTO NV
BY 31/00Z.  30-40KT 500MB SWLY FLOW IS EXPECTED TO OVERSPREAD MT/WY
INTO THE WRN DAKOTAS BY LATE AFTERNOON ENHANCING THE PROSPECT FOR
ORGANIZED CONVECTION ALONG N-S WIND SHIFT...PRIMARILY AFTER 21Z WHEN
CONVECTIVE TEMPERATURES HAVE BEEN BREACHED.  LATEST NAM GUIDANCE
STRONGLY SUGGESTS TSTMS WILL EVOLVE ALONG THIS BOUNDARY ACROSS ERN
MT THEN SPREAD INTO WRN ND WHERE ROUGHLY 35KT SFC-6KM BULK SHEAR IS
EXPECTED TO ALLOW FOR ORGANIZED MULTI-CELL CONVECTION AND PERHAPS
EVEN A WEAK SUPERCELL.  STEEP LAPSE RATE ENVIRONMENT FAVORS LARGE
HAIL AND GUSTY WINDS.  THIS ACTIVITY SHOULD PROPAGATE INTO CNTRL ND
DURING THE LATE EVENING AS STRENGTHENING LLJ SHIFTS EAST DURING THE
OVERNIGHT HOURS.

...ELSEWHERE...

WEAK SRN STREAM SHORT-WAVE TROUGH IS FORECAST TO ADVANCE INTO ERN TX
BY 30/18Z AND A VERY MOIST WARM CONVEYOR SHOULD EXTEND ACROSS THE
WRN GOM INTO THE LOWER OH VALLEY WITH PW VALUES AOA 2 INCHES.
SCT-NUMEROUS THUNDERSTORMS SHOULD EVOLVE ALONG THIS CORRIDOR AIDED
BY DIURNAL HEATING.  FORECAST SOUNDINGS WITHIN THIS MOIST PLUME
EXHIBIT WEAK LAPSE RATES BUT MODEST LOW LEVEL SHEAR...ESPECIALLY
ACROSS THE LOWER MS VALLEY WHERE LLJ MAY INCREASE TO 35-40KT.
VEERING WINDS WITH HEIGHT FAVOR WEAK STORM ROTATION WITH THE
STRONGEST CONVECTION.  HOWEVER...LIMITED BUOYANCY AND EXPECTED LAPSE
RATES DO NOT APPEAR ADEQUATE FOR SEVERE PROBS AT THIS TIME.

..DARROW.. 08/29/2014



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