Severe Storm Outlook Narrative (AC)
Issued by NWS

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346
ACUS02 KWNS 310427
SWODY2
SPC AC 310425

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1125 PM CDT SAT JUL 30 2016

VALID 011200Z - 021200Z

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS THE NORTHERN PLAINS AND
UPPER MS VALLEY...

...SUMMARY...
STRONG STORMS MAY DEVELOP ACROSS THE NORTHERN PLAINS AND UPPER
MISSISSIPPI VALLEY MONDAY AFTERNOON.  GUSTY WINDS AND HAIL COULD BE
NOTED WITH THE STRONGEST STORMS.

...NORTHERN PLAINS/UPPER MS VALLEY...

LARGE-SCALE MID-LEVEL HEIGHT FALLS WILL SPREAD ACROSS SK INTO MB
DURING THE DAY2 PERIOD AS STRONG SHORT-WAVE TROUGH PROGRESSES ACROSS
THE CANADIAN PROVINCES.  500MB SPEED MAX ASSOCIATED WITH THIS
FEATURE SHOULD TRANSLATE EWD ALONG THE U.S./CANADIAN
BORDER...REACHING NERN ND BY LATE AFTERNOON.  IN THE ABSENCE OF
HEIGHT FALLS SOUTH OF THE BORDER...SFC HEATING AND LOW-LEVEL WARM
ADVECTION SHOULD BE THE DRIVING MECHANISMS FOR POTENTIAL CONVECTIVE
DEVELOPMENT.

LATEST SHORT-RANGE MODEL GUIDANCE SUGGESTS CONVECTION MAY BE ONGOING
AT THE START OF THE PERIOD ALONG A CORRIDOR FROM ERN ND INTO
IA...DUE PRIMARILY TO WARM ADVECTION.  IT/S NOT REAL CLEAR HOW
SEVERE THIS ACTIVITY WILL BE AT DAYBREAK AND DIURNAL HEATING COULD
CONTRIBUTE TO RENEWED INTENSITY BY EARLY AFTERNOON ALONG CONVECTIVE
OUTFLOWS.  HOWEVER...STRONG SFC HEATING ACROSS THE PLAINS WILL
LIKELY AID ROBUST TSTM DEVELOPMENT ALONG WEAK SFC BOUNDARY DRAPED
NE-SW ACROSS THE DAKOTAS...AND PERHAPS ALONG E-W WIND SHIFT
REINFORCED BY EARLY-DAY CONVECTION.  00Z GUIDANCE SUGGESTS
CONVECTIVE MODE WILL BE COMPLEX DUE TO THE LACK OF MEANINGFUL
FORCING.  LARGE HAIL AND DAMAGING WINDS ARE THE PRIMARY THREATS WITH
THESE STORMS.

...ELSEWHERE...

STRONG CONVECTION MAY DEVELOP ACROSS PARTS OF SERN AZ BUT ELY
MID-LEVEL FLOW IS NOT FORECAST TO BE PARTICULARLY NOTEWORTHY WITH
500MB FLOW GENERALLY LESS THAN 10KT.  AS A RESULT...POORLY ORGANIZED
UPDRAFTS WILL LIKELY BE THE NORM.

A FEW STRONG STORMS MAY ALSO DEVELOP ACROSS THE MIDDLE ATLANTIC
WHERE POCKETS OF BUOYANCY ARE ABLE TO DEVELOP BENEATH THE UPPER
TROUGH.  FORECAST SHEAR IS SEASONALLY WEAK AND LAPSE RATES ARE NOT
EXPECTED TO BE THAT STEEP.  FOR THIS REASON WILL NOT INTRODUCE
SEVERE PROBS THIS PERIOD.

..DARROW.. 07/31/2016

$$



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