Alert archive / Illinois / Mesoscale Discussions in 2004

Mesoscale Discussion 63

February 2, 200439 counties in Illinois; Des Moines County, Lee County, Scott County, Iowa

The Storm Prediction Center issued this mesoscale discussion at Feb 2, 2004, 1:08 AM CST for 39 counties in Illinois; Des Moines County, Lee County, Scott County, Iowa. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Feb 2, 2004, 1:08 AM CST (07:08 UTC)
Expired: Feb 2, 2004, 5:15 AM CST
In force: 4 hr
Issued by: the Storm Prediction Center

All 42 counties

Des Moines County, IA, Lee County, IA, Scott County, IA, Adams County, IL, Brown County, IL, Bureau County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Coles County, IL, DeWitt County, IL, Douglas County, IL, Ford County, IL, Fulton County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Knox County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Rock Island County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL

The radar

The Lincoln radar (KILX), 15 km from the middle of the area, began a volume at 07:11 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, 7.1 hours before the alert went out and 78 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: 2987 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 157 m²/s²
0-3 km storm-relative helicity: 216 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.

247 
ACUS11 KWNS 020709
SWOMCD
SPC MCD 020708 
ILZ000-IAZ000-MOZ000-021115-

MESOSCALE DISCUSSION 0063
NWS STORM PREDICTION CENTER NORMAN OK
0108 AM CST MON FEB 02 2004

AREAS AFFECTED...NERN MO/SERN IA AND MUCH OF CENTRAL IL

CONCERNING...FREEZING RAIN 

VALID 020708Z - 021115Z

FREEZING RAINFALL RATES RANGING FROM 0.05-0.10 INCHES PER 3 HOURS IS
EXPECTED TO SPREAD NWD ACROSS MUCH OF CENTRAL IL AND EXTREME NERN MO
INTO EXTREME SERN IA DURING THE NEXT 2-3 HOURS...REACHING PORTIONS
OF NWRN IL/FAR EAST CENTRAL IA BY 10Z.

REGIONAL RADARS SHOW A LARGE AREA OF RAINFALL MOVING NWD ACROSS ERN/
SERN MO AND SWRN IL WITH RAINFALL RATES AROUND 0.03 IN/HR.  THIS
ACTIVITY IS ASSOCIATED WITH LOW-LEVEL WAA AS A SLY 40 KT LLJ
INDICATED BY VWP DATA AT STL/MEM/PAH...NOSES INTO THIS REGION. 00Z
SOUNDINGS FROM ERN IA/CENTRAL IL SHOWED DRY LOW-MID LEVELS WITH
CURRENT SURFACE WET-BULB TEMPERATURES ACROSS THE AREA OF CONCERN IN
THE MID-UPPER 20S.  LARGE SCALE ASCENT WILL INCREASE AS THE SRN
PLAINS UPPER TROUGH BECOMES NEGATIVELY TILTED AND BEGINS TO LIFT
NEWD TOWARD THE MID MS VALLEY DURING THE NEXT 6-12 HOURS.  THIS
ASCENT COMBINED WITH PERSISTENT LOW-LEVEL WAA WILL PROVE SUFFICIENT
TO MOISTEN THE BOUNDARY LAYER...RESULTING IN A PERIOD OF FREEZING
RAIN CONTINUING THROUGH THE MORNING /BEYOND 12Z/.

..PETERS.. 02/02/2004

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

ATTN...WFO...LOT...ILX...LSX...DVN...

39348976 39499131 40619179 41949044 41008868 40458790
39778782 39418818

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 1, 7:49 PM CST	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Boone, Calhoun, Carroll and 18 more	5 hr

Nearby

Mesoscale Discussions in Illinois, 2004 Mesoscale Discussions in Iowa, 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; radar from the NEXRAD Level II archive.