Mesoscale Discussion 1024

Issued

Jun 14, 2017, 12:06 PM CDT (17:06 UTC)

Expired

Jun 14, 2017, 2:30 PM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Chance of a watch

60%

The Quad Cities radar (KDVN), 100 km from the middle of the area, began a volume at 17:07 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 328Jun 14, 12:40 PM CDT
• Severe Thunderstorm Watch 329Jun 14, 1:05 PM CDT

715 
ACUS11 KWNS 141706
SWOMCD
SPC MCD 141706 
INZ000-WIZ000-ILZ000-IAZ000-MOZ000-141930-

Mesoscale Discussion 1024
NWS Storm Prediction Center Norman OK
1206 PM CDT Wed Jun 14 2017

Areas affected...Eastern Iowa...South-central Wisconsin...Northwest
Illinois...Far Northeast Missouri

Concerning...Severe potential...Watch possible 

Valid 141706Z - 141930Z

Probability of Watch Issuance...60 percent

SUMMARY...An isolated severe threat is expected to develop this
afternoon across parts of the mid to upper Mississippi Valley. The
stronger thunderstorms could have a potential for isolated large
hail and wind damage. Weather watch issuance may be needed across
the region as storms intensify and increase in coverage.

DISCUSSION...The latest surface analysis shows a very moist airmass
in place across much of the mid to upper Mississippi Valley. Surface
dewpoints are maximized into the lower to mid 70s F from central
Missouri northward into western Illinois and southern Wisconsin.
Surface temperatures have warmed into the 85 to 90 F range along the
moist corridor which is contributing to moderate instability. The
RAP is estimating MLCAPE values in the 2000 to 3000 J/kg range. In
addition, the WSR-88D VWPs at Davenport, IA and Lincoln, IL show
unidirectional wind profiles with some speed shear from just above
the surface into the mid-levels. This is resulting in about 30 kt of
0-6 km shear which will support an isolated severe threat this
afternoon. Although deep-layer shear appears marginal for
supercells, organized multicell clusters should be accompanied by
storms that could produce isolated large hail and wind damage.

..Broyles/Hart.. 06/14/2017

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...GRB...LOT...ILX...MKX...LSX...DVN...ARX...DMX...
EAX...

LAT...LON   40269020 40948914 41278812 41618740 42358729 43908771
            44768842 44988907 44799008 44269062 43009137 41359285
            39969246 40019105 40269020

Mesoscale Discussions in Wisconsin, 2017Mesoscale Discussions in Illinois, 2017Mesoscale Discussions in Iowa, 2017Every mesoscale discussion in 2017

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.