Flash Flooding and Hail in Illinois, May 11, 2005

Name: Flash Flooding and Hail in Illinois, May 11, 2005
Start: 2005-05-11T16:23
End: 2005-05-11T20:00
Location: Illinois

May 11, 2005 · NWS ILX · 11 events in 6 counties and zones

6 hail, 3 flash flood, 2 thunderstorm wind, as filed by the National Weather Service.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 11

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Lincoln, IL wrote its last area forecast discussion before the first event at May 11, 1:00 PM CST, 3 hours 23 minutes earlier.

Area forecast discussion, May 11, 1:00 PM CST, 3 hours 23 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
2 PM CDT WED MAY 11 2005

.DISCUSSION...

WILL BE ISSUING ZONES AND GRIDS A BIT EARLY TODAY WITH ISSUANCE OF
SEVERE THUNDERSTORM WATCH 247.

SHORT TERM...TONIGHT THROUGH SATURDAY...
ABUNDANT MESOSCALE CONCERNS REGARDING POTENTIAL CONVECTION THIS
AFTERNOON AND EVENING. OUTFLOW BOUNDARY FROM LAST NIGHTS CONVECTION
IS NOW IN PLACE FROM NEAR DANVILLE TO TAYLORVILLE AND IS PRODUCING
LOCALLY POOLING DEWPOINTS INTO THE 70S. THE 18Z KILX SOUNDING STILL
SHOWS THE SHALLOW COLD POOL ASSOCIATED WITH THIS BOUNDARY...HOWEVER
WINDS HAVE NOW BECOME SOUTHEAST AT PIA AND GBG AND 18Z SURFACE OBS
INDICATE THAT THE COOLER AIR HAS VIRTUALLY MIXED OUT ALLOWING THE
MAIN BOUNDARY TO REORGANIZE ITSELF NEAR I-80.  IN ADDITION...A
REINFORCEMENT OF THE COOL AIR IS SPEEDING SOUTHWARD THROUGH NORTHERN
ILLINOIS AT THIS TIME AND SHOULD PUSH SOUTH THROUGH AFTERNOON AND
EVENING.

THE COMBINATION OF BOUNDARIES AND POOLING OF MOISTURE HAS ALREADY
PRODUCED MUCAPE VALUES >3000 J/KG SOUTHEAST OF THE ORIGINAL OUTFLOW
WITH LITTLE OR NO CAPE.  WOULD EXPECT SCATTERED DEVELOPMENT ALONG
THIS BOUNDARY THIS AFTERNOON. THIS EVENING...MCS NOW DEVELOPING OVER
NORTHWEST MISSOURI WILL LIKELY TRACK NORTHEAST AND THEN EAST
SOUTHEAST ALONG PLUNGING FRONTAL BOUNDARY.  WOULD EXPECT THAT MUCH
OF THE AREA SHOULD SEE STORMS AT SOME POINT OVERNIGHT GIVEN THE
BOUNDARIES...THE APPROACHING MCS...AND AN INCREASING LLJ.  ONLY
QUESTION IS LACK OF SIGNIFICANT DYNAMICS WITH THE BEST FORCING NORTH
AND WEST OF THE AREA.

SOMEWHAT OF A LULL IS LIKELY ON THURSDAY WITH ONLY SCATTERED
ACTIVITY LIKELY OVER THE CENTRAL AND NORTH.  OF COURSE THAT DEPENDS
ON THE BOUNDARY PLACEMENT IN THE WAKE OF TONIGHTS MCS.

NEXT LIKELY POPS CAN BE EXPECTED ON FRIDAY AS DYNAMICS OF MAIN LOBE
ASSOCIATED WITH UPPER LOW OVER NORTHERN PLAINS REACHES AREA WITH
ASSOCIATED FRONT. COOLER TEMPS ALOFT WILL ENHANCE INSTABILITY
BRINGING ANOTHER POTENTIAL ROUND OF SEVERE WEATHER.

PRECIP WILL LIKELY LINGER INTO SATURDAY UNTIL MAIN TROUGH PASSES
THROUGH.

LONG TERM...SATURDAY THROUGH WEDNESDAY...
NORTHWEST FLOW SHOULD KEEP FORECAST AREA COOL AND DRY INTO NEXT
WEEK.  NEXT SYSTEM APPROACHES THE AREA LATE TUESDAY INTO WEDNESDAY.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
IL...NONE.

&&

BARKER

Hazardous weather outlook, May 11, 10:30 AM CST, 5 hours 53 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
1130 AM CDT WED MAY 11 2005

ILZ027>031-036>038-040>057-061>063-066>068-071>073-121100-
CASS-CHAMPAIGN-CHRISTIAN-CLARK-CLAY-COLES-CRAWFORD-CUMBERLAND-
DE WITT-DOUGLAS-EDGAR-EFFINGHAM-FULTON-JASPER-KNOX-LAWRENCE-LOGAN-
MACON-MARSHALL-MASON-MCLEAN-MENARD-MORGAN-MOULTRIE-PEORIA-PIATT-
RICHLAND-SANGAMON-SCHUYLER-SCOTT-SHELBY-STARK-TAZEWELL-VERMILION-
WOODFORD-
INCLUDING THE CITIES OF...BLOOMINGTON...CHAMPAIGN...DANVILLE...
DECATUR...EFFINGHAM...FLORA...GALESBURG...HAVANA...JACKSONVILLE...
LAWRENCEVILLE...LINCOLN...MATTOON...PEORIA...SHELBYVILLE...
SPRINGFIELD AND TAYLORVILLE
1130 AM CDT WED MAY 11 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL AND SOUTHEAST ILLINOIS.

.DAY ONE...THIS AFTERNOON AND TONIGHT...

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND
SOUTHEAST ILLINOIS THIS AFTERNOON AND INTO THIS EVENING. THE BEST
CHANCES FOR SEVERE STORMS WILL BE FROM PEORIA SOUTHWARD BETWEEN
3 AND 9 PM. LARGE HAIL IS THE MAIN SEVERE WEATHER THREAT. GUSTY
WINDS AND HEAVY RAIN WITH SOME PONDING OF WATER IN URBAN AREAS CAN
ALSO BE EXPECTED.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A CONTINUED CHANCE OF SEVERE THUNDERSTORMS WILL BE POSSIBLE ON
THURSDAY NORTHWEST OF THE ILLINOIS RIVER. THERE IS A SLIGHT CHANCE
OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND SOUTHEAST ILLINOIS FROM
THE ILLINOIS RIVER SOUTHEAST ON FRIDAY AND FRIDAY NIGHT AS A COLD
FRONT MOVES THROUGH ILLINOIS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED BETWEEN 3 AND 9 PM THIS AFTERNOON
AND EARLY EVENING.

&&

THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC AND CLIMATE
INFORMATION...IS AVAILABLE ON THE WEB AT:

HTTP://WWW.WEATHER.GOV/LINCOLN. THIS ADDRESS IS ALL IN LOWER CASE.

HUETTL/SHIMON

The radar

The Lincoln radar (KILX), 35 km away, was scanning. The volume nearest the first event began at 22:20 UTC.

Open the radar archive at this moment

Event by event

6 hail, 3 flash flood, 2 thunderstorm wind. Local standard time, as filed.

Hail, Macon

When: May 11, 4:23 PM CST
Where: Macon County, Maroa
Measured: 0.88 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 40.033, -88.950

Hail, Edgar

When: May 11, 4:40 PM CST
Where: Edgar County, Brocton
Measured: 0.75 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 39.717, -87.933

Hail, Sangamon

When: May 11, 4:45 PM CST
Where: Sangamon County, Springfield
Measured: 0.88 in hail
Reported by: TRAINED SPOTTER
Coordinates: 39.800, -89.650

Hail, Macon

When: May 11, 4:50 PM CST to 5:00 PM CST
Where: Macon County, Blue Mound
Measured: 1.75 in hail
Reported by: EMERGENCY MANAGER
Coordinates: 39.700, -89.117

Hail covered the ground.

Hail, Sangamon

When: May 11, 4:53 PM CST
Where: Sangamon County, Chatham
Measured: 0.75 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 39.667, -89.700

Thunderstorm Wind, Macon

When: May 11, 5:00 PM CST
Where: Macon County, Blue Mound
Measured: 50 kt (58 mph) estimated gust
Reported by: EMERGENCY MANAGER
Coordinates: 39.700, -89.117

Hail, Moultrie

When: May 11, 5:05 PM CST
Where: Moultrie County, Lovington
Measured: 1 in hail
Reported by: OFFICIAL NWS OBS.
Coordinates: 39.717, -88.633

Flash Flood, Macon

When: May 11, 5:42 PM CST to 7:30 PM CST
Where: Macon County, Southwest Portion
Reported by: EMERGENCY MANAGER
Coordinates: 39.850, -88.950

Highway 48 impassible southwest of Blue Mound due to water over road. Additional county roads were also under water in southwest portion of county.

Flash Flood, Moultrie

When: May 11, 6:00 PM CST to 8:00 PM CST
Where: Moultrie County, North Portion
Reported by: TRAINED SPOTTER
Coordinates: 39.633, -88.600

3.5 inches of rain fell in a short period of time in Lovington and produced flash flooding on several city streets making them impassible.

Thunderstorm Wind, Morgan

When: May 11, 6:30 PM CST
Where: Morgan County, Woodson
Measured: 50 kt (58 mph) estimated gust
Reported by: LAW ENFORCEMENT
Coordinates: 39.633, -90.217

A few power lines blown down.

Flash Flood, Christian

When: May 11, 6:55 PM CST to 8:00 PM CST
Where: Christian County, Northeast Portion
Reported by: EMERGENCY MANAGER
Coordinates: 39.533, -89.267

Highway 48 under three feet of water near Christian and Macon county line.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Illinois in 2005 Every state in 2005 This day in weather history Warnings in Illinois, May 2005

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5446766, 5446767, 5446765, 5446760, 5446761, 5446764, 5446762, 5446768, 5446770, 5446763, 5446769.