Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS11 KWNS 181217
SWOMCD
SPC MCD 181217
MNZ000-SDZ000-NDZ000-181445-

MESOSCALE DISCUSSION 1556
NWS STORM PREDICTION CENTER NORMAN OK
0717 AM CDT THU AUG 18 2016

AREAS AFFECTED...SOUTHEAST ND/FAR NORTHEAST SD/WEST-CENTRAL MN

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 181217Z - 181445Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...AT LEAST AN ISOLATED RISK FOR DAMAGING WINDS AND POSSIBLY
SOME HAIL MAY CONTINUE...AND POTENTIALLY INCREASE...ACROSS SOUTHEAST
ND INTO FAR NORTHEAST SD AND WEST-CENTRAL MN THROUGH THE MORNING.
CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE SEVERE
THUNDERSTORM WATCH.

DISCUSSION...A QUASI-LINEAR CLUSTER OF STORMS HAS GRADUALLY
INTENSIFIED DURING THE PRE-DAWN HOURS ACROSS EAST-CENTRAL/SOUTHEAST
ND. A 62-KT WIND GUST WAS RECENTLY REPORTED AT JAMESTOWN ND AS OF
1155Z. WHILE THIS CLUSTER HAS GENERALLY LAGGED JUST BEHIND A
SOUTHEASTWARD-MOVING COLD FRONT OVERNIGHT...A CONTINUED GRADUAL
FORWARD /SOUTHEASTWARD/ ACCELERATION AND DOWNSTREAM
MOISTENING/DESTABILIZATION MAY ALLOW FOR A FURTHER INCREASE IN
QUASI-LINER CONVECTIVE ORGANIZATION AND INTENSIFICATION THIS MORNING
AS CONVECTIVE INHIBITION ERODES. VERY STEEP MID-LEVEL LAPSE RATES
/8.3 C PER KM 700-500 MB/ AND STRONG EFFECTIVE SHEAR /50 KT/ WERE
NOTED IN THE 12Z ABERDEEN SD OBSERVED SOUNDING. WHILE THERE IS SOME
UNCERTAINTY ABOUT THE OVERALL EXTENT/MAGNITUDE OF THE SEVERE RISK
THIS MORNING...CONVECTIVE TRENDS WILL BE CLOSELY MONITORED FOR A
POSSIBLE SEVERE THUNDERSTORM WATCH.

..GUYER.. 08/18/2016

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

ATTN...WFO...DLH...MPX...FGF...ABR...BIS...

LAT...LON   47429793 47379672 46929463 46319431 45489477 45339591
            45659723 46319859 47429793




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