Alert archive / Illinois / Flash Flood Warnings in 2021

Flash Flood Warning 17, NWS Lincoln, IL

July 11, 2021Vermilion County, Illinois

NWS Lincoln, IL issued this flash flood warning at Jul 11, 2021, 9:31 PM CDT for Vermilion County, Illinois. It was in force for 3 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
Jul 11, 2021, 9:31 PM CDT (02:31 UTC)
Expired
Jul 12, 2021, 12:30 AM CDT
In force
3 hr
Issued by
NWS Lincoln, IL
Area
Storm-based polygon
Flood severity
None

County Vermilion County, IL

The radar

The Lincoln radar (KILX), 131 km from the middle of the area, began a volume at 02:30 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, 2.5 hours before the alert went out and 70 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 00:00Z on 2021-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 460 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2021-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 square meters per square second.19395878Sfc1 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
460 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
553 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

519 
WGUS53 KILX 120231
FFWILX
ILC183-120530-
/O.NEW.KILX.FF.W.0017.210712T0231Z-210712T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lincoln IL
931 PM CDT Sun Jul 11 2021

The National Weather Service in Lincoln has issued a

* Flash Flood Warning for...
  Southwestern Vermilion County in east central Illinois...

* Until 1230 AM CDT.

* At 930 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Sidell, Indianola and Jamaica.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3989 8791 3989 8769 3999 8770 4004 8793

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR 

$$

25
2 follow-up statements
270 
WGUS73 KILX 120436
FFSILX

Flash Flood Statement
National Weather Service Lincoln IL
1136 PM CDT Sun Jul 11 2021

ILC183-120530-
/O.CON.KILX.FF.W.0017.000000T0000Z-210712T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Vermilion IL-
1136 PM CDT Sun Jul 11 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT MONDAY 
FOR SOUTH CENTRAL VERMILION COUNTY...

At 1136 PM CDT, Doppler radar indicated thunderstorms producing 
heavy rain across the warned area. Between 3 and 4 inches of rain 
have fallen. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Doppler radar.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Indianola.

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 3989 8782 3989 8772 3995 8771 3995 8776

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR 

$$

37
681 
WGUS73 KILX 120522
FFSILX

Flash Flood Statement
National Weather Service Lincoln IL
1222 AM CDT Mon Jul 12 2021

ILC183-120532-
/O.EXP.KILX.FF.W.0017.000000T0000Z-210712T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Vermilion IL-
1222 AM CDT Mon Jul 12 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1230 AM CDT EARLY THIS MORNING 
FOR SOUTH CENTRAL VERMILION COUNTY...

The heavy rain has ended. Flash flooding is no longer expected to 
pose a threat. Please continue to heed remaining road closures.

LAT...LON 3989 8782 3989 8772 3995 8771 3995 8776

$$

37

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 7:00 PM CDTAreal Flood AdvisoryILXVermilion5 hr
Jul 11, 8:35 PM CDTFlash Flood WarningILXSangamon3 hr
Jul 12, 11:20 AM CDTAreal Flood AdvisoryILXMacon6 hr
Jul 12, 2:54 PM CDTSevere Thunderstorm WarningILXEdgar30 min

Nearby

Flash Flood Warnings in Illinois, 2021Every flash flood warning in 2021

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.