Mesoscale Discussion 912

Issued

Jun 14, 2016, 11:45 AM CDT (16:45 UTC)

Expired

Jun 14, 2016, 1:45 PM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Chance of a watch

60%

The Sioux Falls radar (KFSD), 120 km from the middle of the area, began a volume at 16:47 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

• Severe Thunderstorm Watch 254Jun 14, 12:40 PM CDT
• Tornado Watch 255Jun 14, 2:35 PM CDT

215 
ACUS11 KWNS 141645
SWOMCD
SPC MCD 141645 
IAZ000-MNZ000-NEZ000-SDZ000-141845-

MESOSCALE DISCUSSION 0912
NWS STORM PREDICTION CENTER NORMAN OK
1145 AM CDT TUE JUN 14 2016

AREAS AFFECTED...ERN SD/ERN NEB EWD INTO SWRN MN/IA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 141645Z - 141845Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...STORMS HAVE BEGUN TO INCREASE ACROSS PORTIONS OF ERN NEB
AND IA OVER THE PAST HALF HOUR...WITH CONTINUED INCREASES IN BOTH
COVERAGE AND INTENSITY EXPECTED INTO EARLY AFTERNOON.  WW ISSUANCE
MAY BE NEEDED IN THE NEXT HOUR OR SO.

DISCUSSION...LATEST SURFACE ANALYSIS DEPICTS A SURFACE LOW OVER SERN
SD ATTM...WITH A COOL FRONT EXTENDING SSWWD ACROSS ERN NEB AND INTO
KS...WHILE A WARM FRONT -- BEING RETARDED IN NWD ADVANCE BY ONGOING
CLOUDS/PRECIPITATION -- LYING ESEWD ACROSS THE MN/IA BORDER AREA AND
INTO NRN IL.  WITHIN THE VERY MOIST /LOW 70S DEWPOINTS/ WARM
SECTOR...HEATING THROUGH SCATTERED CLOUDS IS ALLOWING STEADY
DESTABILIZATION TO OCCUR...WITH 1000 TO 2000 J/KG MIXED-LAYER CAPE
NOW WIDESPREAD PER OBJECTIVE ANALYSES.  

VISIBLE SATELLITE HAS REVEALED GRADUAL MATURATION OF THE CU FIELD
ACROSS IA...BUT RECENTLY MORE VIGOROUS TCU/CB DEVELOPMENT HAS
INITIATED ALONG THE COOL FRONT FROM NEAR THE LOW OVER SERN SD SWD
ACROSS ERN NEB.  THE LOCATION AND TIMING OF THIS DEVELOPMENT IS
CONSISTENT WITH AN ENSEMBLE OF CAM GUIDANCE -- WITH THIS GUIDANCE
SUGGESTIVE OF A STEADY INCREASE IN STORMS INVOF BOTH THE COOL AND
WARM FRONTS OVER THE NEXT FEW HOURS.  

AREA VWPS INDICATE GRADUALLY VEERING/INCREASING FLOW WITH HEIGHT
FROM THE BOUNDARY LAYER THROUGH MID LEVELS...SUPPORTIVE OF
ORGANIZED/ROTATING UPDRAFTS.  INITIAL STORMS OVER ERN IA APPEAR TO
BE DEVELOPING LINEARLY...WITH HAIL AND WIND LIKELY TO BE THE MAIN
SEVERE RISKS IN THIS AREA.  GREATER TORNADO RISK WOULD LIKELY EXIST
N/NE OF THIS REGION NEARER THE WARM FRONT AND SURFACE LOW --
PARTICULARLY IF STORMS CAN MAINTAIN MORE CELLULAR STRUCTURE.  GIVEN
CURRENT DEVELOPMENT...WW MAY BE REQUIRED WITHIN THE NEXT HOUR.

..GOSS/GUYER.. 06/14/2016

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

ATTN...WFO...DVN...ARX...MPX...DMX...FSD...OAX...ABR...GID...

LAT...LON   41349776 42249706 43229717 43959793 44789824 45229716
            45339645 44579510 43879340 43369160 41669196 41419389
            40989470 40429670 40489804 40439820 41349776

Mesoscale Discussions in Iowa, 2016Mesoscale Discussions in Nebraska, 2016Mesoscale Discussions in Minnesota, 2016Every mesoscale discussion in 2016

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.