Alert archive / Illinois / Flash Flood Warnings in 2018

Flash Flood Warning 37, NWS St. Louis, MO

September 7, 2018Adams County, Illinois

NWS St. Louis, MO issued this flash flood warning at Sep 7, 2018, 10:33 AM CDT for Adams County, Illinois. It was in force for 6 hr. 1 report 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
Sep 7, 2018, 10:33 AM CDT (15:33 UTC)
Expired
Sep 7, 2018, 4:30 PM CDT
In force
6 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

County Adams County, IL

The radar

The St Louis radar (KLSX), 165 km from the middle of the area, began a volume at 15:34 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
Sep 7, 11:36 AM CDTFLOOD2 W Camp Point, ILWATER OVER PARTS OF HIGHWAY 24 WEST OF CAMP POINT. DEPTH OF WATER UNKNOWN BUT REPORTS INDICATE THE HIGHWAY REMAINS OPEN.

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 3.6 hours before the alert went out and 182 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 12:00Z on 2018-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Davenport, at 12:00Z on 2018-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
877 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

848 
WGUS53 KLSX 071533
FFWLSX
ILC001-072130-
/O.NEW.KLSX.FF.W.0037.180907T1533Z-180907T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
1033 AM CDT FRI SEP 7 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Northern Adams County in west central Illinois...

* Until 430 PM CDT.

* At 1030 AM CDT, Doppler radar indicated persistent heavy rain 
  across the warned area. Very efficient rainfall production has 
  resulted in high rainfall rates. Radar indicates that up to three 
  inches of rain have already fallen since 900 AM in the region 
  bounded by Fowler, Mendon, and Camp Point. Flash flooding is 
  expected to begin shortly.

* Some locations that will experience flooding include...
  Quincy, Camp Point, Mendon, La Grange, Clayton, Golden, Ursa,
  Loraine, Woodville, Lima, Coatsburg, Columbus, La Prairie, Meyer,
  Paloma, Fowler and Chatton.

This includes Interstate 172 near exit 19.
 
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.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

LAT...LON 4019 9092 3998 9092 3996 9145 4003 9150
      4006 9149 4012 9151 4019 9151 4020 9150

$$

Glass
1 follow-up statement
586 
WGUS73 KLSX 071815
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
115 PM CDT FRI SEP 7 2018

ILC001-072130-
/O.CON.KLSX.FF.W.0037.000000T0000Z-180907T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Adams IL-
115 PM CDT FRI SEP 7 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 PM CDT FOR
NORTHERN ADAMS COUNTY...

At 111 PM CDT, Doppler radar continued to show widespread rain which 
was heavy at times across the warned area. Radar estimates suggest 
anywhere from two to three and a half inches of rain has already 
fallen since early this morning. The highest amounts have been 
centered on an axis from southeast of La Grange eastward through 
Camp Point. 

Some locations that will experience flooding include...
Quincy, Camp Point, Mendon, La Grange, Clayton, Golden, Ursa,
Loraine, Woodville, Lima, Coatsburg, Columbus, La Prairie, Meyer,
Paloma, Fowler and Chatton.

Additional rainfall amounts of 1 to 2 inches are possible through 
late afternoon in the warned area.

This includes Interstate 172 near exit 19.
 
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.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

LAT...LON 4019 9092 3998 9092 3996 9145 4003 9150
      4006 9149 4012 9151 4019 9151 4020 9150

$$

Glass

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 8:26 PM CDTRiver Flood WarningLSXBrown60 hr
Sep 6, 10:20 PM CDTRiver Flood WarningLSXAdams6 days
Sep 7, 10:12 AM CDTAreal Flood AdvisoryLSXAdams3 hr
Sep 7, 4:31 PM CDTAreal Flood WarningLSXAdams18 hr
Sep 7, 5:31 PM CDTFlash Flood WarningLSXBond, Fayette, Macoupin, Montgomery6 hr

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.