Alert archive / Indiana / Mesoscale Discussions in 2003

Mesoscale Discussion 375

April 4, 20034 states

The Storm Prediction Center issued this mesoscale discussion at Apr 4, 2003, 1:29 PM CST for 4 states. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Apr 4, 2003, 1:29 PM CST (19:29 UTC)
Expired
Apr 4, 2003, 3:00 PM CST
In force
91 min
Issued by
the Storm Prediction Center
All 50 counties

Bureau County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Lee County, IL, Marshall County, IL, Putnam County, IL, Stark County, IL, Will County, IL, Adams County, IN, Allen County, IN, DeKalb County, IN, Elkhart County, IN, Fulton County, IN, Huntington County, IN, Jasper County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Newton County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Wabash County, IN, Wells County, IN, Whitley County, IN, Berrien County, MI, Branch County, MI, Cass County, MI, Saint Joseph County, MI, Allen County, OH, Defiance County, OH, Fulton County, OH, Hancock County, OH, Henry County, OH, Paulding County, OH, Putnam County, OH, Van Wert County, OH, Williams County, OH, Wood County, OH

The radar

The Northern Indiana radar (KIWX), 61 km from the middle of the area, began a volume at 19:29 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 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, 7.5 hours before the alert went out and 231 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-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2003-04-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 60 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2003-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -8 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
60 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
622 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
-8 m²/s²
0-3 km storm-relative helicity
91 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

630 
ACUS11 KWNS 041930
SWOMCD
SPC MCD 041929 
OHZ000-MIZ000-INZ000-ILZ000-042100-

MESOSCALE DISCUSSION 0375
NWS STORM PREDICTION CENTER NORMAN OK
0129 PM CST FRI APR 04 2003

AREAS AFFECTED...NRN IL...NRN IND...EXTREME SRN LOWER MI AND NWRN
OH

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 041929Z - 042100Z

...ISOLD LARGE HAIL IS LIKELY ACROSS THE AREA THIS AFTERNOON...



A WW PROBABLY WILL NOT BE NEEDED GIVEN ISOLD NATURE OF THE SEVERE
POTENTIAL.



ELEVATED TSTMS HAVE INCREASED OVER THE PAST COUPLE OF HOURS
ACROSS NRN IL EWD INTO NRN IND AND EXTREME NWRN OH...LIKELY AIDED
BY INCREASING LARGE SCALE ASCENT IN EXIT REGION OF A APPROACHING
MIDLEVEL JETLET.  PARCELS THAT ARE CONVECTING ATOP THE COLD DOME
ARE MORE THAN LIKELY ORIGINATING FROM THE UNSTABLE AIR MASS
UPSTREAM ACROSS MO/DOWNSTATE IL WHERE MUCAPES ARE APPROACHING
2000 J/KG.  THE STORMS APPEAR TO REACH PEAK INTENSITY AS THEY
APPROACH AND CROSS THE STATIONARY FRONT SITUATED FROM NRN IL INTO
NRN IND AND NWRN OH.  THUS...GIVEN STEEP MIDLEVEL LAPSE
RATES...COLD COLUMN AND FAVORABLE SHEAR IN THE CAPE BEARING
LAYER...A FEW ORGANIZED TSTMS HAVE RESULTED.  LARGE HAIL WILL BE
THE PRIMARY THREAT...BUT RELATIVELY ISOLD ENOUGH TO NOT INCLUDE
IN A SEVERE THUNDERSTORM WATCH.  THE GREATER SEVERE THREAT WILL
EXIST FARTHER SOUTH ACROSS CNTRL/SRN PARTS OF IND/IL AND SWRN OH.

..RACY.. 04/04/2003

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

ATTN...WFO...CLE...ILN...DTX...IWX...GRR...LOT...ILX...DVN...

42208753 42118628 42048537 41768399 41508331 40688354
40648498 40748562 40918693 41038872 40848986 41768986

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 4, 7:23 AM CSTMesoscale DiscussionSPCAdams, Bond, Brown, Calhoun, Cass, Champaign and 55 more97 min
Apr 4, 9:47 AM CSTMesoscale DiscussionSPCClark, Coles, Crawford, Cumberland, Douglas, Edgar and 9 more58 min
Apr 4, 11:10 AM CSTMesoscale DiscussionSPCBond, Calhoun, Cass, Champaign, Christian, Clinton and 24 more95 min
Apr 4, 12:05 PM CSTTornado WatchSPCAdams, Brown, Calhoun, Cass, Greene, Jersey and 10 more5 hr
Apr 4, 1:12 PM CSTMesoscale DiscussionSPCBond, Brown, Calhoun, Cass, Champaign, Christian and 35 more93 min
Apr 4, 2:35 PM CSTTornado WatchSPCBond, Champaign, Christian, Clark, Clay, Clinton and 26 more5 hr
Apr 4, 3:10 PM CSTMesoscale DiscussionSPCBond, Champaign, Christian, Clark, Coles, Cumberland and 25 more2 hr
Apr 4, 4:25 PM CSTTornado WatchSPCAlexander, Bond, Clay, Clinton, Edwards, Franklin and 24 more6 hr
Apr 4, 5:11 PM CSTMesoscale DiscussionSPCBond, Champaign, Christian, Clark, Clay, Clinton and 24 more2 hr
Apr 3, 10:43 PM CSTMesoscale DiscussionSPCBarry, Clinton, Eaton, Genesee, Ingham, Ionia and 7 more5 hr

Nearby

Mesoscale Discussions in Indiana, 2003Mesoscale Discussions in Illinois, 2003Mesoscale Discussions in Ohio, 2003Every mesoscale discussion in 2003

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.