Alert archive / Indiana / Mesoscale Discussions in 2012

Mesoscale Discussion 389

March 30, 201231 counties in Illinois; 60 counties in Indiana; 32 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2012, 1:12 PM CDT for 31 counties in Illinois; 60 counties in Indiana; 32 counties in Ohio. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Mar 30, 2012, 1:12 PM CDT (18:12 UTC)
Expired: Mar 30, 2012, 2:45 PM CDT
In force: 93 min
Issued by: the Storm Prediction Center

All 123 counties

Bond County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Lawrence County, IL, Marion County, IL, Moultrie County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Adams County, IN, Allen County, IN, Bartholomew County, IN, Blackford County, IN, Boone County, IN, Brown County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Dearborn County, IN, Decatur County, IN, Delaware County, IN, Dubois County, IN, Fayette County, IN, Fountain County, IN, Franklin County, IN, Gibson County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Jackson County, IN, Jay County, IN, Jefferson County, IN, Jennings County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Martin County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Ohio County, IN, Orange County, IN, Owen County, IN, Parke County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Randolph County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Sullivan County, IN, Tipton County, IN, Union County, IN, Vanderburgh County, IN, Vermillion County, IN, Vigo County, IN, Warrick County, IN, Washington County, IN, Wayne County, IN, Wells County, IN, Allen County, OH, Auglaize County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clinton County, OH, Crawford County, OH, Darke County, OH, Delaware County, OH, Fayette County, OH, Franklin County, OH, Greene County, OH, Hamilton County, OH, Hancock County, OH, Hardin County, OH, Logan County, OH, Madison County, OH, Marion County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Morrow County, OH, Paulding County, OH, Pickaway County, OH, Preble County, OH, Putnam County, OH, Seneca County, OH, Shelby County, OH, Union County, OH, Van Wert County, OH, Warren County, OH, Wyandot County, OH

The radar

The Indianapolis radar (KIND), 31 km from the middle of the area, began a volume at 18:15 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 6.2 hours before the alert went out and 187 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: 164 J/kg
Mixed-layer CIN: -244 J/kg
Mixed-layer LCL: 1045 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 206 m²/s²
0-3 km storm-relative helicity: 230 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.

561 
ACUS11 KWNS 301813
SWOMCD
SPC MCD 301812
OHZ000-KYZ000-INZ000-ILZ000-301945-

MESOSCALE DISCUSSION 0389
NWS STORM PREDICTION CENTER NORMAN OK
0112 PM CDT FRI MAR 30 2012

AREAS AFFECTED...WRN/CNTRL OH...CNTRL/SRN IND...SRN IL

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 301812Z - 301945Z

THUNDERSTORM DEVELOPMENT IS FORECAST TO TAKE PLACE DURING THE NEXT
FEW HRS ACROSS PORTIONS OF WRN OH SWWD INTO CNTRL IND AND SRN IL.
SVR STORMS WILL BE PROBABLE...AND A WW ISSUANCE WILL LIKELY BE
NEEDED BY 19-20Z.

MIDDAY MESOANALYSIS PLACES AN AREA OF SURFACE LOW PRESSURE OVER NWRN
IND AT 17Z...WHICH IS COINCIDENT WITH A MIDLEVEL IMPULSE MOVING E
ACROSS LK MI. WARM SECTOR AIRMASS...CHARACTERIZED BY TEMPERATURES
WARMING INTO THE MID TO UPR 70S WITH DEWPOINTS FROM THE MID 50S TO
LOW 60S...IS BOUNDED BY A COLD FRONT EXTENDING SWWD INTO CNTRL/SRN
MO...AND A WARM FRONT EXTENDING SEWD INTO ERN KY. STEEP MIDLEVEL
LAPSE RATES NEAR 8 C/KM RESIDE ABOVE THE DESTABILIZING WARM SECTOR
AIRMASS...AND WILL AID IN MLCAPE VALUES FROM 1000-1500 J/KG BY PEAK
HEATING. MEANWHILE...AS THE AFTERNOON PROGRESSES...THE SURFACE LOW
AND WARM FRONT WILL ADVANCE INTO OH...WHILE THE COLD FRONT DROPS
S-SEWD TOWARD SRN IND AND IL. THE COMBINATION OF CONVERGENCE AND
BOUNDARY LAYER DESTABILIZATION ALONG THE FRONT...AS WELL AS WEAK
LARGE-SCALE ASCENT ASSOCIATED WITH THE PREVIOUSLY MENTIONED UPPER
WAVE...SHOULD BE SUFFICIENT FOR THUNDERSTORM INITIATION ALONG THE
COLD FRONT...PERHAPS AS EARLY AS 19-20Z BASED ON RECENT RUNS OF THE
HRRR.

MIDLEVEL WLYS RANGE FROM 50 KT NEAR THE LK MI IMPULSE...TO 20-30 KT
OVER SRN IL...AND WILL YIELD SUFFICIENTLY STRONG DEEP-LAYER VERTICAL
WIND SHEAR /I.E. 0-6 KM BULK WIND DIFFERENCE FROM 20-40 KT/ FOR
ORGANIZED MULTICELL AND SUPERCELL STORM DEVELOPMENT. GIVEN THE
LINEAR NATURE OF LOW-LEVEL FORCING ALONG THE COLD FRONT...STORMS MAY
TEND TO ORGANIZE INTO LINE SEGMENTS...AND WILL POSE A THREAT FOR
DAMAGING WINDS AND LARGE HAIL. CLOSER TO THE SURFACE LOW AND WARM
FRONT OVER IND AND OH...SURFACE WINDS WILL BE MORE STRONGLY
BACKED...WHICH WILL MAXIMIZE LOW-LEVEL VERTICAL WIND SHEAR /0-1 KM
SRH AOA 150 M2 S-2/...AND INCREASE THE POTENTIAL FOR TORNADOES.

..GARNER.. 03/30/2012

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

ATTN...WFO...CLE...ILN...LMK...IWX...IND...PAH...ILX...LSX...

LAT...LON   41168501 41178263 39738277 37788809 37678948 38269010
            39318941 41168501

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 30, 2:51 PM CDT	Severe Thunderstorm Watch	SPC	Bond, Clark, Clay, Clinton, Coles, Crawford and 26 more	7 hr
Mar 30, 2:24 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Allen, Bartholomew, Blackford, Boone, Brown and 44 more	7 hr
Mar 30, 6:02 PM CDT	Mesoscale Discussion	SPC	Bartholomew, Brown, Clay, Daviess, Dearborn, Decatur and 23 more	28 min
Mar 30, 6:47 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Athens, Belmont, Brown, Carroll, Clermont and 22 more	4 hr

Nearby

Mesoscale Discussions in Indiana, 2012 Mesoscale Discussions in Ohio, 2012 Mesoscale Discussions in Illinois, 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.