Mesoscale Discussion 1102

Issued

Jun 30, 2016, 6:16 PM CDT (23:16 UTC)

Expired

Jun 30, 2016, 8:15 PM CDT

In force

119 min

Issued by

the Storm Prediction Center

Chance of a watch

20%

The Quad Cities radar (KDVN), 175 km from the middle of the area, began a volume at 23:18 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.

327 
ACUS11 KWNS 302316
SWOMCD
SPC MCD 302316 
ILZ000-MOZ000-IAZ000-010115-

MESOSCALE DISCUSSION 1102
NWS STORM PREDICTION CENTER NORMAN OK
0616 PM CDT THU JUN 30 2016

AREAS AFFECTED...SOUTHEASTERN IOWA...WEST-CENTRAL ILLINOIS...AND
NORTHEASTERN MISSOURI

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 302316Z - 010115Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THE THREAT FOR ISOLATED SEVERE WIND GUSTS ASSOCIATED WITH
ORGANIZED LINE SEGMENTS AND PERHAPS A SMALL MCS IS INCREASING
THROUGH THE EARLY EVENING...BUT COVERAGE OF SEVERE WIND GUSTS IS
EXPECTED TO BE ISOLATED...PRECLUDING THE NEED FOR A WATCH.

DISCUSSION...OVER THE NORTHERN PART OF THE AREA...THE ATMOSPHERE HAS
DESTABILIZED IN THE WAKE OF EARLIER SHOWERS AND THUNDERSTORMS AND
SITS DOWNSTREAM OF AN ORGANIZING LINE SEGMENT BETWEEN DVN AND DSM.
ANOTHER LINE SEGMENT IS BECOMING ORGANIZED OVER NORTHERN MISSOURI.
THE CORE OF STRONGER MID-LEVEL FLOW...40-45 KT AT 500
MB...ASSOCIATED WITH A PERTURBATION IN THE NORTHWEST FLOW ALSO IS
SPREADING OVER THE AREA. NEAR-SURFACE WINDS WITH A MORE SOUTHERLY
COMPONENT RESIDE AHEAD OF EACH LINE SEGMENT AND ARE CONTRIBUTING TO
EFFECTIVE BULK SHEAR OF 35-45 KT...A LITTLE HIGHER THAN ANTICIPATED
EARLIER IN THE DAY. MLCAPE VALUES OF 1000-1500 J/KG AHEAD OF THE
NORTHERN LINE SEGMENT...AND 1500-2500 J/KG AHEAD OF THE SOUTHERN
LINE SEGMENT...ARE SUPPORTIVE OF CONTINUED CONVECTIVE ORGANIZATION
ALONG THE SMALL DEVELOPING COLD POOLS. MODERATE LOW-LEVEL LAPSE
RATES...PARTICULARLY WHERE TEMPERATURES HAVE WARMED TO THE LOW
80S...COULD FOSTER THE PRODUCTION OF ISOLATED SEVERE WIND GUSTS WITH
THE PASSAGE OF EITHER SYSTEM. HOWEVER...THE CORRIDOR OF INSTABILITY
IS RELATIVELY NARROW...PARTICULARLY FOR THE NORTHERN SYSTEM...AND
CONVECTIVELY-INDUCED HIGH-LEVEL CLOUDS SPREADING IN AHEAD OF BOTH
SYSTEMS SHOULD LIMIT ANY FURTHER DESTABILIZATION. THEREFORE THE
THREAT FOR SEVERE WINDS SHOULD REMAIN ISOLATED AND A WATCH IS NOT
EXPECTED...ALTHOUGH TRENDS WILL CONTINUE TO BE MONITORED.

..CONIGLIO/COHEN/GUYER.. 06/30/2016

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

ATTN...WFO...ILX...LSX...DVN...DMX...EAX...

LAT...LON   41509220 41409257 41209278 40979261 40769248 40689258
            40379270 40109333 39859392 39519398 39209366 38999327
            38909254 39009190 39169130 39399077 39759023 40008989
            40258965 40558960 40868980 41129017 41299064 41469142
            41549182 41509220

Mesoscale Discussions in Missouri, 2016Mesoscale Discussions in Illinois, 2016Mesoscale Discussions in Iowa, 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.