Severe Storm Outlook Narrative (AC)
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ACUS03 KWNS 280742
SWODY3
SPC AC 280741

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0241 AM CDT SAT MAY 28 2016

VALID 301200Z - 311200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE WRN DAKOTAS
AND NWRN NEB...

...THERE IS A MRGL RISK OF SVR TSTMS FROM THE NRN PLAINS SWD INTO
THE CNTRL AND SRN HIGH PLAINS...

...THERE IS A MRGL RISK OF SVR TSTMS FOR PARTS OF NEW ENGLAND...

...SUMMARY...
ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF THE
NORTHERN GREAT PLAINS SOUTHWARD INTO THE CENTRAL AND SOUTHERN HIGH
PLAINS MONDAY AFTERNOON AND EVENING.  ISOLATED STRONG TO SEVERE
STORMS MAY DEVELOP OVER PORTIONS OF NEW ENGLAND DURING THE
AFTERNOON.

...N-CNTRL HIGH PLAINS INTO SRN MN...
MODELS ARE IN RELATIVELY GOOD AGREEMENT IN SHOWING A SHORTWAVE
TROUGH MOVE FROM THE NRN ROCKIES INTO THE NRN PLAINS BY OVERNIGHT
MONDAY.  A SURFACE LOW IS FORECAST TO DEVELOP NEAR THE BLACK HILLS
AND MOVE EWD INTO THE ERN DAKOTAS BY TUESDAY MORNING.  THE
DEVELOPMENT OF SURFACE LOW PRESSURE WILL INVOKE MOISTURE TO STREAM
NWD ON SLY LOW-LEVEL FLOW.  MODERATE DESTABILIZATION IS PROGGED BY
MODEL GUIDANCE WITH THE SRN FRINGE OF STRONGER WLY/S OVERSPREADING
THE DESTABILIZING WARM SECTOR.  ISOLD TO SCATTERED STORMS ARE
FORECAST TO DEVELOP BY LATE AFTERNOON WITH ONE OR MORE ORGANIZED
STORM CLUSTERS MOVING E/SE ACROSS SD AND PERHAPS NEB DURING THE
EVENING AND PERHAPS LINGERING INTO THE OVERNIGHT...RESULTING IN AN
ISOLD THREAT FOR LARGE HAIL/DMGG WINDS.

...CNTRL AND SRN HIGH PLAINS...
THE LEE TROUGH/DRYLINE WILL LIKELY FOCUS WIDELY-SPACED THUNDERSTORM
DEVELOPMENT DURING THE AFTERNOON/EVENING.  LOW-LEVEL MOISTURE
RETURNING NWD ON SLY FLOW WILL LIKELY YIELD BOUNDARY-LAYER DEWPOINTS
RANGING FROM THE MID-UPPER 50S TO 60S DURING THE AFTERNOON AS STRONG
HEATING/MIXING OCCURS.  STEEP H7-H5 LAPSE RATES WILL CONTRIBUTE TO
MODERATE TO STRONG BUOYANCY /SBCAPE 1500-3500 J/KG/.  A BELT OF
STRONGER MID- TO HIGH-LEVEL FLOW ASSOCIATED WITH THE SRN STREAM WILL
OVERSPREAD THE SRN HIGH PLAINS AND RESULT IN SHEAR PROFILES
SUPPORTIVE OF MULTICELLS AND SUPERCELLS GIVEN THE LARGE BUOYANCY AND
SLY WINDS VEERING TO WLY WITH HEIGHT.  YET...WEAK FORCING ALOFT IN
AREAS CASTS CONSIDERABLE UNCERTAINTY ON STORM DEVELOPMENT/LOCATION
FROM THE CNTRL HIGH PLAINS SWD.  HIGHER SEVERE PROBABILITIES MAY
LARGELY DEPEND ON WHERE POTENTIAL CLUSTERS OF STORMS DEVELOP AND
GROW UPSCALE DURING THE EVENING HOURS AS A SLY LLJ INTENSIFIES.

...NEW ENGLAND...
A BELT OF MODERATE TO STRONG WSWLY H5 FLOW /30-40 KT/ ASSOCIATED
WITH A WEAK SHORTWAVE TROUGH IS FORECAST TO MOVE ACROSS SRN QUEBEC
DURING THE DAY 3 PERIOD.  UPPER 50S DEWPOINTS IN INTERIOR NEW
ENGLAND TO THE 60S OVER SRN NEW ENGLAND AND HEATING WILL RESULT IN
WEAK DESTABILIZATION BY EARLY AFTERNOON ALONG AND AHEAD OF A WEAK
COLD FRONT FORECAST TO MOVE ACROSS THE REGION WITH ISOLD STORMS
DEVELOPING BY THE MID AFTERNOON.  ISOLD STRONG DOWNDRAFTS CAPABLE OF
A WIND-DAMAGE RISK AND PERHAPS SMALL HAIL MAY ACCOMPANY THE STRONGER
STORMS WITH THE ACTIVITY WEAKENING BY EARLY EVENING.

..SMITH.. 05/28/2016

$$



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