Alert archive / Illinois / Mesoscale Discussions in 2012

Mesoscale Discussion 393

March 30, 201214 counties in Illinois; Gibson County, Indiana

The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2012, 7:26 PM CDT for 14 counties in Illinois; Gibson County, Indiana. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: Mar 30, 2012, 7:26 PM CDT (00:26 UTC)
Expired: Mar 30, 2012, 8:30 PM CDT
In force: 64 min
Issued by: the Storm Prediction Center

Counties Clay County, IL, Crawford County, IL, Edwards County, IL, Franklin County, IL, Hamilton County, IL, Jasper County, IL, Jefferson County, IL, Lawrence County, IL, Marion County, IL, Perry County, IL, Richland County, IL, Wabash County, IL, Wayne County, IL, White County, IL, Gibson County, IN

The radar

The Evansville,IN radar (KVWX), 105 km from the middle of the area, began a volume at 00:29 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.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.4 hours before the alert went out and 195 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1523 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

629 
ACUS11 KWNS 310026
SWOMCD
SPC MCD 310026 
INZ000-ILZ000-MOZ000-310130-

MESOSCALE DISCUSSION 0393
NWS STORM PREDICTION CENTER NORMAN OK
0726 PM CDT FRI MAR 30 2012

AREAS AFFECTED...SRN IL AND FAR SWRN IND

CONCERNING...SEVERE THUNDERSTORM WATCH 119...

VALID 310026Z - 310130Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 119
CONTINUES.

HOWEVER...RECENT TRENDS IN REGIONAL RADAR IMAGERY AND LIGHTNING DATA
SUGGEST THE OVERALL POTENTIAL FOR ADDITIONAL STRONGER STORMS CAPABLE
OF PRODUCING SEVERE HAIL AND DAMAGING WINDS APPEARS TO BE
DIMINISHING.  OBJECTIVE ANALYSES INDICATED MLCAPE REMAINS AROUND
1000 J/KG ACROSS SRN IL INTO FAR SWRN IND AND FAR WRN KY.  MARGINAL
EFFECTIVE BULK SHEAR OF 20-30 KT WILL MAINTAIN MULTICELL STORM MODE
THROUGH THE EVENING.  THE LACK OF MORE ROBUST TSTMS IS ATTENDANT TO
THE WEAKER SHEAR AND THE DECREASE IN STRONGER FORCING ALOFT AS A
SHORTWAVE TROUGH MOVES FARTHER AWAY FROM THIS REGION THROUGH THE
LOWER GREAT LAKES.  ALTHOUGH SOME INCREASE IN FORCING FOR ASCENT
WILL SPREAD INTO THIS REGION WITH THE APPROACH OF A SHORTWAVE
TROUGH...NOW MOVING THROUGH IA...THE ONSET OF DIABATIC
COOLING/INCREASED SURFACE BASED INHIBITION AND DECREASING
INSTABILITY SHOULD NOT PROVE FAVORABLE FOR NEW STRONG TSTM
DEVELOPMENT.

..PETERS.. 03/31/2012

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

ATTN...WFO...IND...PAH...ILX...LSX...

LAT...LON   37709012 38298929 38808907 39018861 39168762 38218754
            37709012

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 30, 9:25 PM CDT	Mesoscale Discussion	SPC	Edwards, Franklin, Gallatin, Hamilton, Jackson, Saline and 3 more	35 min

Nearby

Mesoscale Discussions in Illinois, 2012 Mesoscale Discussions in Indiana, 2012 Every mesoscale discussion in 2012

Sources

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.