Alert archive / Illinois / Flash Flood Warnings in 2026

Flash Flood Warning 55, NWS Lincoln, IL

August 13, 20265 counties in Illinois

NWS Lincoln, IL issued this flash flood warning at Aug 13, 2026, 11:21 PM CDT for 5 counties in Illinois. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 13, 2026, 11:21 PM CDT (04:21 UTC)
Expired
Aug 14, 2026, 2:51 AM CDT
In force
4 hr
Issued by
NWS Lincoln, IL
Area
Storm-based polygon
Flood severity
None

Counties Knox County, IL, Marshall County, IL, Peoria County, IL, Stark County, IL, Woodford County, IL

The radar

The Quad Cities radar (KDVN), 73 km from the middle of the area, began a volume at 04:22 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 4.4 hours before the alert went out and 71 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, Davenport, at 00:00Z on 2026-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 352 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, Davenport, at 00:00Z on 2026-08-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 134 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
352 J/kg
Mixed-layer CIN
-129 J/kg
Mixed-layer LCL
573 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
134 m²/s²
0-3 km storm-relative helicity
448 m²/s²
Significant tornado parameter
0.2
Supercell composite
4.5

Open this sounding in Storm Lab

The text

As transmitted.

867 
WGUS53 KILX 140421
FFWILX
ILC095-123-143-175-203-140800-
/O.NEW.KILX.FF.W.0055.260814T0421Z-260814T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lincoln IL
1121 PM CDT Thu Aug 13 2026

The National Weather Service in Lincoln has issued a

* Flash Flood Warning for...
  Southwestern Marshall County in central Illinois...
  Northern Peoria County in central Illinois...
  Northwestern Woodford County in central Illinois...
  Southern Stark County in north central Illinois...
  Northern Knox County in west central Illinois...

* Until 300 AM CDT.

* At 1121 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Galesburg, Chillicothe, Wyoming, Toulon, Knoxville, Princeville, 
  Rome, Dunlap, Wataga, Oneida, Williamsfield, Altona, Spring Bay, 
  Victoria, Henderson, La Fayette, Rio, Elmore, Laura and Edelstein.

This includes the following State Parks...
Snakeden Hollow State Fish and Wildlife Area and Woodford State Fish 
and Wildlife Area.

This includes  Interstate 74 between  mile markers 34 and 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4095 9044 4098 9044 4100 9044 4102 9044
      4104 9044 4106 9044 4109 9044 4111 9044
      4115 9044 4115 9036 4115 9032 4115 9025
      4111 8998 4102 8946 4081 8937 4083 8953
      4087 8999 4092 9044

FLASH FLOOD...RADAR INDICATED

$$

Deubelbeiss
1 follow-up statement
474 
WGUS73 KILX 140751
FFSILX

Flash Flood Statement
National Weather Service Lincoln IL
251 AM CDT Fri Aug 14 2026

ILC095-123-143-175-203-140801-
/O.CAN.KILX.FF.W.0055.000000T0000Z-260814T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Knox IL-Marshall IL-Peoria IL-Stark IL-Woodford IL-
251 AM CDT Fri Aug 14 2026

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN MARSHALL, 
NORTHERN PEORIA, NORTHWESTERN WOODFORD, SOUTHERN STARK AND NORTHERN 
KNOX COUNTIES...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 1000 AM CDT Friday for 
portions of central, east central, and west central Illinois.

&&

LAT...LON 4095 9044 4098 9044 4100 9044 4102 9044
      4104 9044 4106 9044 4109 9044 4111 9044
      4115 9044 4115 9036 4115 9032 4115 9025
      4111 8998 4102 8946 4081 8937 4083 8953
      4087 8999 4092 9044

$$

25

What forecasters said that day

The local office's own words before this flash flood warning went out, 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 this flash flood warning went out at Aug 13, 6:24 PM CDT, 4 hours 57 minutes earlier. Its key messages:

  • Flash flooding is a concern along and north of the I-74 corridor overnight. HREF probabilities of more than 2 inches of rain are 30-50% in this area, although some local totals over 3 inches are possible.
  • Heat index values of 100 to 105 degrees will continue into the weekend each afternoon, in areas near and south of I-70. The heat is expected to spread northward across the forecast area by Saturday.
Area forecast discussion, Aug 13, 6:24 PM CDT, 4 hours 57 minutes before
Area Forecast Discussion
National Weather Service Lincoln IL
624 PM CDT Thu Aug 13 2026

.KEY MESSAGES...

- Flash flooding is a concern along and north of the I-74
  corridor overnight. HREF probabilities of more than 2 inches
  of rain are 30-50% in this area, although some local totals
  over 3 inches are possible.

- Heat index values of 100 to 105 degrees will continue into the
  weekend each afternoon, in areas near and south of I-70. The
  heat is expected to spread northward across the forecast area
  by Saturday.

&&

.DISCUSSION...
Issued at 235 PM CDT Thu Aug 13 2026

MCS that tracked out of Iowa earlier today intensified again as
it crossed the Peoria metro, producing winds around 70 mph and
extensive damage in Bloomington. Cluster of storms has reached
the Champaign area this hour, with the trailing outflow
extending west through Springfield. Storms are riding along a
tight gradient of CAPE and should exit the forecast area in the
next few hours.

Next MCS is expected to begin developing this evening closer to
the warm front from Iowa to northern Indiana, then sink
southward overnight. Precipitable water values over 2 inches
persist through the night, and some of the northern parts of our
forecast area have seen a few inches of rain since yesterday.
HREF PMM precip estimates suggest 1.5-2 inches of rain in 6
hours between midnight and sunrise, and no changes are being
made to the Flood Watch at this time. South half of the forecast
area has a good chance of remaining dry until closer to
daybreak.

Heat forecasts remain a concern as well. Latest guidance
suggests 100-105 heat index could reach as far north as a
Rushville-Paris line tomorrow, but the extent of the lingering
rain/cloud shield introduces some uncertainty as to whether or
not to expand the Heat Advisory. Current inclination is to leave
it in place and allow the next shift to expand it, once the
timing and track of the MCS becomes more certain. An expansion
for the entire forecast area appears more likely for Saturday.

A quick look at the extended forecast -- upper pattern becomes
more zonal for a time as high pressure sprawls more west-east
across the southern U.S. Getting into early next week, riding
amplifies west of the Rockies as a strong upper trough swings
across the Canadian Prairies and the north central U.S. Impacts
from that in our area would be more likely toward the middle of
next week. A couple days of cooler temperatures are likely
early next week, before warming begins again.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 623 PM CDT Thu Aug 13 2026

Storms from earlier this afternoon have cleared the terminals
leaving VFR conditions and east/southeast winds across central
Illinois. IFR ceilings are in place just north of PIA/BMI this
evening and expected to expand south towards the I-74 corridor
overnight while MVFR ceilings develop across the remainder of
central IL by late tonight. Meanwhile, additional showers and
storms will form tonight along a stationary front over the
region and continue into Friday morning. Confidence in
placement and timing remains low at this time but are generally
favored between I-72 and I-80.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Friday morning for ILZ027>031-037-038-045-
046.
Heat Advisory until 8 PM CDT Sunday for ILZ066>068-071>073.

&&

KEY MESSAGES...Geelhart
DISCUSSION...Geelhart
AVIATION...Deubelbeiss
Hazardous weather outlook, Aug 13, 3:04 PM CDT, 8 hours 17 minutes before
Hazardous Weather Outlook
National Weather Service Lincoln IL
304 PM CDT Thu Aug 13 2026

ILZ027>031-036>038-040>057-061>063-066>068-071>073-142015-
Knox-Stark-Peoria-Marshall-Woodford-Fulton-Tazewell-McLean-Schuyler-
Mason-Logan-De Witt-Piatt-Champaign-Vermilion-Cass-Menard-Scott-
Morgan-Sangamon-Christian-Macon-Moultrie-Douglas-Coles-Edgar-Shelby-
Cumberland-Clark-Effingham-Jasper-Crawford-Clay-Richland-Lawrence-
304 PM CDT Thu Aug 13 2026

This Hazardous Weather Outlook is for central Illinois, east
central Illinois, southeast Illinois and west central Illinois.

.DAY ONE...Tonight.

Heat indices of 95 to 110 are expected this afternoon south of I-72.

Additional thunderstorms are expected late tonight into Friday
morning with damaging winds and large hail possible with any
stronger storms. Heavy rain could locally exceed 3 inches and produce
localized flooding. Areas for strong to severe storms and flooding
will be most likely near and north of I-74

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Hot and humid conditions will expand northward through late week.
Peak afternoon heat indices will range from 100 to 110 Friday and
Saturday, and Sunday from I-72 southward.

Daily chances for thunderstorms exist through the weekend, although
these will be mainly north of I-72 Friday afternoon through Sunday
morning. Some of these storms could be severe and produce heavy rain
through at least Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed late tonight.

Expected storm motion is toward the east around 30 mph.

37

In the hours before

Local storm report, Aug 13, 8:22 PM CDT, 2 hours 59 minutes before
Preliminary Local Storm Report
National Weather Service Lincoln IL
822 PM CDT Thu Aug 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0105 PM     Non-Tstm Wnd Gst 1 S Bloomington         40.46N 89.00W
08/13/2026  M49 MPH          McLean             IL   Mesonet

            Mesonet station DVI02877 Bloomington.

&&
Local storm report, Aug 13, 8:36 PM CDT, 2 hours 45 minutes before
Preliminary Local Storm Report
National Weather Service Lincoln IL
836 PM CDT Thu Aug 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0259 PM     Tstm Wnd Gst     Coles County Airport    39.47N 88.27W
08/13/2026  M45 MPH          Coles              IL   ASOS

            Corrects previous non-tstm wnd gst report
            from Coles County Airport. ASOS station KMTO
            Coles Co. Mem AP.

&&

07
Local storm report, Aug 13, 8:37 PM CDT, 2 hours 44 minutes before
Preliminary Local Storm Report
National Weather Service Lincoln IL
837 PM CDT Thu Aug 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0208 PM     Tstm Wnd Gst     Willard Airport         40.03N 88.28W
08/13/2026  M52 MPH          Champaign          IL   ASOS

            Corrects previous non-tstm wnd gst report
            from Willard Airport. ASOS station KCMI
            Willard Arpt.

&&

07
Local storm report, Aug 13, 8:45 PM CDT, 2 hours 36 minutes before
Preliminary Local Storm Report
National Weather Service Lincoln IL
845 PM CDT Thu Aug 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 PM     Rain             1 SSW Germantown Hills  40.76N 89.48W
08/13/2026  M1.43 Inch       Woodford           IL   Mesonet

            Mesonet station AX391 GERMANTOWN HILLS.

&&
Local storm report, Aug 13, 8:57 PM CDT, 2 hours 24 minutes before
Preliminary Local Storm Report
National Weather Service Lincoln IL
857 PM CDT Thu Aug 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0240 PM     Flood            1 SE Champaign          40.10N 88.24W
08/13/2026                   Champaign          IL   Public

            One vehicle stranded from flooding on Neil
            St south of Kirby Ave. Police blocked off
            Kirby Ave near Neil St.

&&

07
Special weather statement, Aug 13, 11:11 PM CDT, 10 minutes before
Special Weather Statement
National Weather Service Lincoln IL
1111 PM CDT Thu Aug 13 2026

ILZ029-140445-
Peoria-
1111 PM CDT Thu Aug 13 2026

...A STRONG THUNDERSTORM WILL IMPACT NORTHERN PEORIA COUNTY THROUGH
1145 PM CDT...

At 1111 PM CDT, Doppler radar was tracking a strong thunderstorm near
Dunlap, or 7 miles northwest of Peoria, moving southeast at 20 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Peoria, Chillicothe, Bellevue, Princeville, Dunlap, Edelstein,
Kickapoo, Norwood, Jubilee College State Park, and Alta.

This includes the following highways...
 Interstate 474 between mile markers 0 and 2.
 Interstate 74 between mile markers 75 and 87.

This also includes Jubilee College State Park and Rock Island Trail
State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4082 8988 4097 8979 4096 8945 4069 8970
TIME...MOT...LOC 0411Z 299DEG 16KT 4082 8972

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Deubelbeiss

The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 13, 11:11 PM CDTSpecial Weather StatementILXPeoria34 min
Aug 13, 11:32 PM CDTSpecial Weather StatementILXWoodford43 min
Aug 13, 11:56 PM CDTSpecial Weather StatementILXPeoria34 min
Aug 14, 12:05 AM CDTSevere Thunderstorm WarningILXChampaign, Vermilion55 min
Aug 14, 12:18 AM CDTSevere Thunderstorm WarningILXPeoria, Tazewell, Woodford57 min
Aug 14, 12:40 AM CDTFlash Flood WarningILXVermilion12 hr
Aug 14, 1:07 AM CDTSpecial Weather StatementILXVermilion23 min
Aug 14, 1:12 AM CDTSevere Thunderstorm WarningILXMcLean52 min
Aug 14, 1:38 AM CDTFlash Flood WarningILXChampaign, McLean7 hr
Aug 14, 2:33 AM CDTSevere Thunderstorm WarningILXChampaign, Piatt, Vermilion46 min
Aug 14, 2:59 AM CDTFlash Flood WarningILXChampaign, Vermilion6 hr
Aug 14, 4:07 AM CDTFlash Flood WarningILXFulton, Knox, Peoria, Tazewell6 hr
Aug 14, 5:47 AM CDTFlash Flood WarningILXDeWitt, Piatt3 hr
Aug 14, 6:47 AM CDTFlash Flood WarningILXColes, Douglas, Edgar11 hr
Aug 14, 8:14 AM CDTFlash Flood WarningILXClark, Coles, Cumberland, Edgar3 hr
Aug 14, 9:25 AM CDTRiver Flood WarningILXVermilion4 days
Aug 14, 10:00 AM CDTFlash Flood WarningILXCass, Fulton, Logan, Mason, Menard, Sangamon4 hr
Aug 14, 10:20 AM CDTRiver Flood WarningILXFulton, Knox4 days
Aug 14, 10:32 AM CDTAreal Flood AdvisoryILXMacon3 hr
Aug 14, 12:15 PM CDTFlood WatchILXChampaign, DeWitt, Douglas, Edgar, Fulton, Knox and 10 more22 hr
Aug 14, 3:09 PM CDTRiver Flood WarningILXFulton5 days

Nearby

Flash Flood Warnings in Illinois, 2026Every flash flood warning in 2026

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.