ZCZC SPCSWOMCD ALL
ACUS11 KWNS 041946 
SPC MCD 041946 
NEZ000-SDZ000-KSZ000-COZ000-042145-

MESOSCALE DISCUSSION 1632
NWS STORM PREDICTION CENTER NORMAN OK
0246 PM CDT SUN SEP 04 2016

AREAS AFFECTED...PORTIONS OF SOUTHWEST/CENTRAL SD...WESTERN/CENTRAL
NEB...FAR NORTHEAST CO...AND FAR NORTHWEST KS

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 041946Z - 042145Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...INITIAL DISCRETE STORM DEVELOPMENT WILL BE POSSIBLE
THROUGH 22Z ACROSS SOUTHEAST WY AND NORTHEAST CO INTO ADJACENT
SOUTHWEST SD AND THE WESTERN PART OF THE NEB PANHANDLE.  THESE
INITIAL STORMS WILL BE CAPABLE OF PRODUCING PRIMARILY HAIL AND
STRONG WIND GUSTS.  A FURTHER INCREASE IN STORM COVERAGE AND
SEVERITY /PRIMARILY DAMAGING WINDS/ IS EXPECTED FROM NORTHEAST CO
THROUGH THE NEB PANHANDLE TO SOUTHWEST SD BY 23Z...WITH STORMS
SPREADING TO THE EAST-NORTHEAST THROUGH THE EVENING.

DISCUSSION...TRENDS IN SATELLITE IMAGERY AND LIGHTNING DATA
SUGGESTED THE LEADING EXTENT OF STRONGER FORCING FOR ASCENT
ATTENDANT TO A PROGRESSIVE SHORTWAVE TROUGH...LOCATED IN CENTRAL WY
TO NORTHWEST CO AT 19Z...IS MOVING INTO EASTERN WY AND NORTH-CENTRAL
TO NORTHEAST CO.  THIS INCREASE IN UPWARD VERTICAL MOTION IS
SUPPORTING TSTM DEVELOPMENT ALONG ITS LEADING EDGE FROM
SOUTH-CENTRAL TO SOUTHEAST WY...AND PERHAPS THE NEWLY FORMED STORMS
IN NORTHEAST CO AND WITHIN UPSLOPE FLOW ACROSS SOUTHWEST SD. 
INSTABILITY IS GENERALLY MARGINAL IN THESE AFOREMENTIONED STORM
LOCATIONS...THOUGH BULK SHEAR HAS BEEN STRENGTHENING THIS AFTERNOON
FROM EASTERN CO/WY TO CENTRAL NEB/SD.  THE CAPE/SHEAR PARAMETER
SPACE WITH THE INITIAL STORMS SHOULD SUPPORT PRIMARILY A THREAT FOR
HAIL AND STRONG WIND GUSTS.  

MEANWHILE...SURFACE ANALYSES INDICATED A STALLED FRONT EXTENDING
FROM NORTHEAST ND TO CENTRAL SD TO THE NORTHWEST NEB
PANHANDLE...WITH AN AREA OF LOW PRESSURE LOCATED ALONG THIS BOUNDARY
NEAR PIR...AND A SECOND AREA OF LOW PRESSURE EXTENDING FROM
EAST-CENTRAL TO SOUTHEAST WY.  AS THE LEADING EDGE OF LIFT ATTENDANT
TO THE WY/CO SHORTWAVE TROUGH SPREADS TO THE EAST-NORTHEAST ATOP
RICHER ENVIRONMENTAL MOISTURE/INSTABILITY FROM FAR NORTHEAST CO
THROUGH WESTERN NEB AND SOUTHWEST/SOUTH-CENTRAL SD...STORM
COVERAGE/INTENSITY ARE EXPECTED TO INCREASE.  HAIL AND DAMAGING
WINDS WILL BE THE PRIMARY THREATS.

..PETERS/HART.. 09/04/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...ABR...GID...LBF...UNR...GLD...BOU...CYS...

LAT...LON   39980308 40770358 43570346 44430188 44520015 43609966
            41679987 40549994 40150012 39870062 39680162 39660220
            39980308 

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