Mesoscale Discussion 477

Issued

Apr 27, 2016, 5:34 PM CDT (22:34 UTC)

Expired

Apr 27, 2016, 7:30 PM CDT

In force

116 min

Issued by

the Storm Prediction Center

The Pleasant Hill radar (KEAX), 165 km from the middle of the area, began a volume at 22:34 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.

355 
ACUS11 KWNS 272235
SWOMCD
SPC MCD 272234 
MOZ000-ILZ000-IAZ000-280030-

MESOSCALE DISCUSSION 0477
NWS STORM PREDICTION CENTER NORMAN OK
0534 PM CDT WED APR 27 2016

AREAS AFFECTED...PORTIONS OF SOUTHERN IOWA...MISSOURI...AND WESTERN
IL

CONCERNING...TORNADO WATCH 116...

VALID 272234Z - 280030Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 116 CONTINUES.

SUMMARY...THE THREAT FOR LARGE HAIL...GUSTY WINDS...AND A FEW
TORNADOES SHOULD CONTINUE SHIFTING TOWARDS EASTERN PORTIONS OF THE
WATCH OVER THE NEXT FEW HOURS. ADDITIONALLY...A STRONG/SEVERE STORM
OR TWO WILL CONTINUE TO BE POSSIBLE ACROSS CENTRAL/SOUTHERN
MISSOURI...BUT RELATIVELY SPARSE COVERAGE SHOULD PRECLUDE WATCH
ISSUANCE.

DISCUSSION...THE LATEST SATELLITE IMAGERY AND SURFACE OBSERVATIONS
INDICATE A WARM FRONT CONTINUES TO STRETCH FROM FAR EASTERN
NEB...THROUGH FAR SOUTHWESTERN IOWA AND NORTHERN MO...AND THEN
ACROSS SOUTH-CENTRAL IL. THE FRONT HAS SHOWN ONLY SOME GRADUAL
NORTHWARD PROGRESS...AND SUPER-RAPID SCAN IMAGERY CONTINUES TO
INDICATE STABLE WAVE CLOUD STRUCTURES OVER FAR NORTHEASTERN MO AND
WEST-CENTRAL IL. THE ONGOING TORNADO THREAT WILL BE CONFINED TO
AREAS ALONG AND SOUTH OF THESE STRUCTURES...WITH SOME LOCALIZED
UPTICK NEAR THE SFC FRONT WHERE LOW-LEVEL BACKING OF WINDS IS
ENHANCED. INDEED...FAR NORTHERN PORTIONS OF THE WATCH MAY FAIL TO
REALIZE ANY TORNADIC POTENTIAL...AS A LEADING STRATIFORM REGION
MAINTAINS COOL/STABLE AIR HERE...REINFORCING THE SFC BOUNDARY TO THE
SOUTH. OVER TIME...CONTINUED UPSCALE GROWTH MAY ALLOW LINE SEGMENTS
TO PROGRESS FARTHER EAST LATER THIS EVENING...OUTSIDE EAST/NORTHEAST
SECTIONS OF THE WATCH. WHILE THE TORNADO THREAT MAY DIMINISH SOME
/AND ENTIRELY IF CONVECTIVE MOVEMENT TAKES THE CELLS NORTH OF THE
BOUNDARY/...SOME WIND AND HAIL THREAT MAY BE MAINTAINED...AND A NEW
WATCH MAY BE CONSIDERED.

FARTHER SOUTH ACROSS MISSOURI...AN ISOLATED SEVERE CELL OR TWO WILL
BE CAPABLE OF STRONG WINDS AND LARGE HAIL...DUE TO CONSIDERABLE
BUOYANCY WITHIN THE HAIL GROWTH ZONE AND SUFFICIENT EFFECTIVE SHEAR
FOR UPDRAFT ROTATION/ORGANIZATION. NONETHELESS...VIGOROUS CONVECTIVE
DEVELOPMENT ALONG THE EASTWARD-PROGRESSING SURFACE TROUGH SHOULD
REMAIN SPARSE ENOUGH TO PRECLUDE WATCH ISSUANCE.

..PICCA.. 04/27/2016

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

ATTN...WFO...PAH...ILX...LSX...DVN...SGF...DMX...EAX...OAX...

LAT...LON   40689500 41419524 41489362 40429071 40139009 38659010
            37539014 36639053 36559212 38439301 38979399 40689500

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