Severe Storm Outlook Narrative (AC)
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000
ACUS48 KWNS 300653
SWOD48
SPC AC 300652

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0152 AM CDT SAT JUL 30 2016

VALID 021200Z - 071200Z

...DISCUSSION...
SRN FRINGE OF STRONGER WLY FLOW WILL LIKELY EXTEND INTO THE NRN TIER
OF THE CONUS THROUGH THE MEDIUM RANGE PERIOD AS UPPER RIDGE
PROGRESSES INTO THE MIDDLE OF THE COUNTRY.  TWO SHORT-WAVE TROUGHS
OF INTEREST WILL EJECT ALONG THE U.S./CANADIAN BORDER WITH THE
SECOND FEATURE LIKELY BEING MORE EFFICIENT INDUCING ORGANIZED
CONVECTION ACROSS THE NRN PLAINS INTO THE UPPER MS VALLEY.  WHILE
STRONG STORMS MAY BE NOTED DAY4/TUE ACROSS ERN MT IN ADVANCE OF THE
STRONGER SHORT WAVE...FORECAST MOISTURE/INSTABILITY MAY BE A BIT TOO
MEAGER TO WARRANT 15 PERCENT SEVERE PROBS THIS PERIOD.

OF MORE CONCERN IS THE POTENTIAL FOR ORGANIZED SEVERE LATER DAY5/WED
OVER THE NRN PLAINS/DAKOTAS.  IT APPEARS THE NRN ROCKIES SHORT-WAVE
TROUGH WILL SUPPRESS HEIGHTS ACROSS THE NRN PLAINS BY MID
WEEK...LIKELY INDUCING ROBUST CONVECTION WHERE BUOYANCY WILL BE
GREATER.  HOWEVER...ECMWF IS NOTABLY FASTER WITH THIS FEATURE THAN
THE GFS AND TIMING ISSUES WILL PRECLUDE THE ADDITION OF A SEVERE
RISK THIS PERIOD.  BEYOND DAY5...ORGANIZED CONVECTION MAY DEVELOP
DOWNSTREAM INTO THE GREAT LAKES REGION BUT PREDICTABILITY REMAINS
TOO LOW GIVEN THE TIMING DIFFERENCES.

..DARROW.. 07/30/2016


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