Severe Storm Outlook Narrative (AC)
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ACUS48 KWNS 220853
SWOD48
SPC AC 220853

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0353 AM CDT FRI AUG 22 2014

VALID 251200Z - 301200Z

...DISCUSSION...
AS AN UPPER SHORT-WAVE TROUGH CONTINUES ITS NEWD DEPARTURE FROM THE
N CENTRAL U.S. DAY 4 /MON 8-25/...RIDGING IS PROGGED TO PREVAIL
ACROSS THE SRN AND ERN U.S. WHILE A LONGER WAVELENGTH WRN U.S.
TROUGH MOVES SLOWLY EWD.  CONVECTION -- AND POSSIBLE SEVERE WEATHER
-- APPEARS LIKELY TO EVOLVE INVOF A COLD FRONT TRAILING SWWD FROM
THE UPPER GREAT LAKES TO THE CENTRAL HIGH PLAINS...AS THE SRN FRINGE
OF A BELT OF STRONGER MID-LEVEL SWLYS SHOULD RESIDE ATOP THE SURFACE
FRONTAL ZONE.  SOME CONCENTRATION OF RISK MAY OCCUR INVOF THE ERN
CO/KS/NEB VICINITY...NEAR AND JUST TO THE COOL SIDE OF THE FRONT
WHERE SHEAR WOULD BE MAXIMIZED.  HOWEVER...WITH THE GFS MORE
AGGRESSIVE WITH MID-LEVEL HEIGHT FALLS SPREADING INTO THE HIGH
PLAINS THAN THE ECMWF...CONFIDENCE IN A WIDESPREAD/SUBSTANTIAL
SEVERE EVENT REMAINS LIMITED -- AND THUS INSUFFICIENT FOR INCLUSION
OF A 30 PERCENT EQUIVALENT RISK AREA.

FROM DAY 5 ONWARD...DIFFERENCES AMONGST MEDIUM-RANGE MODELS BECOME
EVEN MORE SUBSTANTIAL...NOTABLY WITH RESPECT TO STRENGTH AND SPEED
OF THE WRN TROUGH /AND ASSOCIATED EFFECTS ON SURFACE PATTERN
EVOLUTION/ AS THIS FEATURE CROSSES THE ROCKIES AND SHIFTS INTO THE
CENTRAL CONUS.  AS SUCH...NO HIGHLIGHTS OF ANY SEVERE RISK AREAS
WILL BE INCLUDED THROUGH THE REST OF THE PERIOD.

..GOSS.. 08/22/2014


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