Alert archive / Indiana / Mesoscale Discussions in 2004

Mesoscale Discussion 48

January 26, 20046 counties in Illinois; 32 counties in Indiana; Henderson County, Union County, Kentucky

The Storm Prediction Center issued this mesoscale discussion at Jan 26, 2004, 10:15 PM CST for 6 counties in Illinois; 32 counties in Indiana; Henderson County, Union County, Kentucky. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jan 26, 2004, 10:15 PM CST (04:15 UTC)
Expired: Jan 27, 2004, 1:15 AM CST
In force: 3 hr
Issued by: the Storm Prediction Center

All 40 counties

Edwards County, IL, Gallatin County, IL, Hamilton County, IL, Lawrence County, IL, Wabash County, IL, White County, IL, Bartholomew County, IN, Boone County, IN, Brown County, IN, Clay County, IN, Crawford County, IN, Daviess County, IN, Dubois County, IN, Gibson County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Jackson County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Martin County, IN, Monroe County, IN, Morgan County, IN, Orange County, IN, Owen County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Shelby County, IN, Spencer County, IN, Sullivan County, IN, Tipton County, IN, Vanderburgh County, IN, Warrick County, IN, Henderson County, KY, Union County, KY

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 4.3 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 522 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 62 m²/s²
0-3 km storm-relative helicity: 132 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.

553 
ACUS11 KWNS 270415
SWOMCD
SPC MCD 270415 
INZ000-KYZ000-ILZ000-270715-

MESOSCALE DISCUSSION 0048
NWS STORM PREDICTION CENTER NORMAN OK
1015 PM CST MON JAN 26 2004

AREAS AFFECTED...PARTS OF SRN IL/WRN KY THROUGH SRN/CNTRL IND

CONCERNING...PRECIPITATION TRENDS....FREEZING RAIN/HEAVY SNOW 

VALID 270415Z - 270715Z

PRECIPITATION RATES WILL INCREASE FROM SOUTHERN INTO CENTRAL INDIANA
NEXT SEVERAL HOURS.  PERIOD OF LIGHT TO MODERATE FREEZING RAIN IS
LIKELY BEFORE HEAVY SNOW...AT TIMES IN EXCESS OF 1 INCH PER
HOUR...DEVELOPS.

STRONG MID-LEVEL JET STREAK CONTINUES TO PROPAGATE EAST
NORTHEASTWARD THROUGH THE LOWER MISSISSIPPI.  AGEOSTROPHIC FORCING
FOR UPWARD VERTICAL MOTION AND MID-LEVEL COOLING/DESTABILIZATION IN
ITS EXIT REGION IS SUPPORTING AN AREA OF INCREASING CONVECTION
ACROSS THE LOWER OHIO VALLEY.  THIS NOW INCLUDES AREAS NEAR/NORTH OF
THE RIVER...FROM EXTREME SOUTHERN ILLINOIS INTO PARTS OF SOUTHERN
INDIANA...WHERE SHALLOW SUB-FREEZING LAYER WEST OF SLOW MOVING
SURFACE FRONT IS SUPPORTING FREEZING RAIN.

MODELS ARE NOW SIMILAR IN SUGGESTING CONSOLIDATING/DEEPENING SURFACE
LOW ALONG SURFACE FRONT ACROSS SOUTHEASTERN INDIANA DURING THE
06-09Z TIME FRAME.  THIS IS SUPPORTED BY LATEST OBSERVATIONAL
DATA...AND SUBSTANTIAL LOWER/MID TROPOSPHERIC COOLING WILL RESULT IN
CHANGEOVER TO SNOW FROM SOUTHERN ILLINOIS/WESTERN KENTUCKY INTO
SOUTHERN INDIANA AFTER 06Z.

STRONGER FORCING IN EXIT REGION OF MID-LEVEL JET WILL SPREAD INTO
SOUTHERN INDIANA DURING THE NEXT 2 TO 4 HOURS...WHERE/WHEN
STRENGTHENING LOW-LEVEL FORCING FOR UPWARD VERTICAL MOTION IS
EXPECTED TO BE ONGOING.  THIS WILL BE ACCOMPANIED BY SIGNIFICANT
INCREASE IN SNOWFALL RATES...AS MAXIMUM LARGE-SCALE ASCENT COINCIDES
WITH FAVORABLE DENDRITIC ICE CRYSTAL GROWTH TEMPERATURES IN THE MID
TROPOSPHERE.

3 TO 4 HOUR PERIOD OF HEAVY SNOW APPEARS LIKELY...INCLUDING ISOLATED
CONVECTIVE BURSTS...SPREADING IN A SWATH ACROSS THE
BLOOMINGTON/INDIANAPOLIS AREAS BY 12Z.

..KERR.. 01/27/2004

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

ATTN...WFO...LMK...IND...PAH...ILX...

38988761 39488708 40188670 40418597 39808535 39008589
38188646 37938705 37568767 37618835 38058863 38598814

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 27, 2:08 AM CST	Mesoscale Discussion	SPC	Adams, Allen, Blackford, Boone, Carroll, Cass and 19 more	5 hr

Nearby

Mesoscale Discussions in Indiana, 2004 Mesoscale Discussions in Illinois, 2004 Mesoscale Discussions in Kentucky, 2004 Every mesoscale discussion in 2004

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.