Alert archive / Illinois / Flash Flood Warnings in 2018

Flash Flood Warning 15, NWS St. Louis, MO

June 25, 2018Monroe County, Saint Clair County, Washington County, Illinois

NWS St. Louis, MO issued this flash flood warning at Jun 25, 2018, 8:01 PM CDT for Monroe County, Saint Clair County, Washington County, Illinois. It was in force for 6 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 25, 2018, 8:01 PM CDT (01:01 UTC)
Expired
Jun 26, 2018, 2:00 AM CDT
In force
6 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

Counties Monroe County, IL, Saint Clair County, IL, Washington County, IL

The radar

The St Louis radar (KLSX), 98 km from the middle of the area, began a volume at 01:04 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.

What was reported inside it

TimeReportWhereRemark
Jun 25, 9:39 PM CDTFLASH FLOOD1 S Marissa, ILVEHICLE SUBMERGED ALONG ST. CLAIR AVENUE IN MARISSA AND DRIVER HAD TO BE RESCUED.
Jun 25, 10:46 PM CDTFLASH FLOOD3 Ne Marissa, ILA CULVERT OVERFLOWED AND WASHED OUT PORTIONS OF ERB ROAD NORTHEAST OF MARISSA.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 1.0 hours before the alert went out and 227 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 2018-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 216 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 2018-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.1939Sfc1 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
216 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
1020 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
185 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

515 
WGUS53 KLSX 260101
FFWLSX
ILC133-163-189-260700-
/O.NEW.KLSX.FF.W.0015.180626T0101Z-180626T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
801 PM CDT MON JUN 25 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  East central Monroe County in southwestern Illinois...
  Southwestern Washington County in south central Illinois...
  Southeastern St. Clair County in southwestern Illinois...

* Until 200 AM CDT.

* At 800 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have 
  already fallen and heavy rainfall continues to fall. Flash 
  flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Waterloo, Nashville, Smithton, New Athens, Marissa, Lively Grove,
  St. Libory, Lenzburg, Hecker, Fayetteville, Oakdale, Floraville,
  Cordes, Elkton, Paderborn and Stone Church.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3822 8939 3824 9009 3838 9017 3837 8938

$$

KD
1 follow-up statement
753 
WGUS73 KLSX 260242
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
942 PM CDT MON JUN 25 2018

ILC133-163-189-260700-
/O.CON.KLSX.FF.W.0015.000000T0000Z-180626T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe IL-Washington IL-St. Clair IL-
942 PM CDT MON JUN 25 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 200 AM CDT FOR
EAST CENTRAL MONROE...SOUTHWESTERN WASHINGTON AND SOUTHEASTERN ST.
CLAIR COUNTIES...

At 941 PM CDT, local law enforcement reported flash flooding due to 
previous thunderstorms. Up to four inches of rain have fallen. Flash 
flooding is ongoing.

Some locations that will experience flooding include...
Waterloo, Nashville, Smithton, New Athens, Marissa, Lively Grove, St.
Libory, Lenzburg, Hecker, Fayetteville, Oakdale, Floraville, Cordes,
Elkton, Paderborn and Stone Church.

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.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3822 8939 3824 9009 3838 9017 3837 8938

$$

KD

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 25, 7:48 PM CDTSevere Thunderstorm WarningLSXMonroe, Saint Clair42 min
Jun 26, 5:34 AM CDTSevere Thunderstorm WarningLSXMonroe26 min
Jun 26, 6:15 AM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion22 min
Jun 26, 8:43 AM CDTSpecial Weather StatementLSXMarion47 min
Jun 26, 9:47 AM CDTAreal Flood AdvisoryLSXClinton, Marion3 hr
Jun 26, 11:22 AM CDTRiver Flood WarningLSXCalhoun, Greene, Jersey14 days

Nearby

Flash Flood Warnings in Illinois, 2018Every flash flood warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.