Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS11 KWNS 052046
SWOMCD
SPC MCD 052046
MNZ000-IAZ000-SDZ000-NEZ000-052245-

MESOSCALE DISCUSSION 1307
NWS STORM PREDICTION CENTER NORMAN OK
0346 PM CDT SUN JUL 05 2015

AREAS AFFECTED...CENTRAL/SRN SD...PORTIONS OF NRN NEB...NWRN
IA...SWRN MN

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 052046Z - 052245Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE
21Z-00Z TIME FRAME WITH LARGE HAIL AND DAMAGING WINDS LIKELY AND A
TORNADO OR TWO POSSIBLE. THE AREA IS BEING MONITORED AND A WATCH IS
LIKELY PRIOR TO 23Z.

DISCUSSION...RECENT VISIBLE IMAGERY SHOWS A DEVELOPING CU FIELD
ACROSS SOUTHERN SD...NEAR AND SLIGHTLY IN ADVANCE OF A COMPOSITE
FRONTAL/OUTFLOW BOUNDARY. STRONG DIURNAL HEATING HAS RESULTED IN
MODERATE/LOCALLY VERY STRONG SURFACE-BASED INSTABILITY WITH MLCAPE
RANGING FROM 1500 J/KG OVER FAR SOUTHWEST SD TO NEAR 4000 J/KG OVER
SOUTH-CENTRAL/SOUTHEAST SD...AND LITTLE/NO REMAINING CINH.
DEEP-LAYER SHEAR AVERAGES 30-40 KTS ACROSS THE DISCUSSION AREA AS
THE REGION IS ON THE SOUTHERN FRINGE OF STRONGER MID-LEVEL FLOW. A
WEAK UPPER LEVEL IMPULSE OVER WESTERN CO/WY WILL MOVE EAST THROUGH
THIS EVENING AND PROVIDE MODEST LARGE-SCALE FORCING FOR ASCENT.

THUNDERSTORM DEVELOPMENT APPEARS PROBABLE IN THE 21Z-00Z TIME FRAME
ALONG THE FRONT...AND PERHAPS IN THE VICINITY OF THE BLACK HILLS
WITH PERSISTENT MOIST LOW-LEVEL UPSLOPE FLOW. STORMS SHOULD QUICKLY
BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS LIKELY. A TORNADO
OR TWO WILL BE POSSIBLE...ESPECIALLY NEAR THE SURFACE BOUNDARY GIVEN
THE MAGNITUDE OF THE INSTABILITY. UPSCALE GROWTH INTO A
FORWARD-PROPAGATING MCS IS LIKELY TOWARDS EVENING WITH A CONTINUED
DAMAGING WIND/QLCS TORNADO RISK.

RADAR/SATELLITE TRENDS WILL CONTINUE TO BE MONITORED AND A WATCH IS
LIKELY PRIOR TO 23Z.

..BUNTING/MEAD.. 07/05/2015

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

ATTN...WFO...MPX...FSD...OAX...ABR...LBF...UNR...CYS...

LAT...LON   44630321 44810209 44410108 44320034 44339975 44599883
            44979702 44629617 44039562 42869575 42519676 42269852
            42009987 42000064 42780375 43460385 44630321



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