Alert archive / Illinois / Flash Flood Warnings in 2018

Flash Flood Warning 24, NWS St. Louis, MO

July 14, 2018Randolph County, Illinois

NWS St. Louis, MO issued this flash flood warning at Jul 14, 2018, 10:03 PM CDT for Randolph County, Illinois. It was in force for 5 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 14, 2018, 10:03 PM CDT (03:03 UTC)
Expired
Jul 15, 2018, 3:24 AM CDT
In force
5 hr
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Flood severity
None

County Randolph County, IL

The radar

The St Louis radar (KLSX), 122 km from the middle of the area, began a volume at 03:03 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

Nashville Metro, TN (KBNA), launched 00:00Z, 3.1 hours before the alert went out and 340 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, Nashville Metro, TN at 00:00Z on 2018-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1359 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, Nashville Metro, TN at 00:00Z on 2018-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
1359 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
1376 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

571 
WGUS53 KLSX 150303
FFWLSX
ILC157-150900-
/O.NEW.KLSX.FF.W.0024.180715T0303Z-180715T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
1003 PM CDT SAT JUL 14 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Eastern Randolph County in southwestern Illinois...

* Until 400 AM CDT Sunday.

* At 959 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area.  Radar estimates that 2 to 4 
  inches of rain has fallen between Steeleville and Sparta. Flash 
  flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Chester, Sparta, Bremen, Steeleville, Percy, Eden, Preston, Blair,
  Houston, Rockwood, Walsh, Welge, New Palestine and Shiloh Hill.

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 3785 8966 3783 8966 3782 8968 3780 8968
      3782 8971 3785 8974 3785 8979 3787 8980
      3788 8980 3791 8984 3787 8990 3817 8985
      3816 8959 3795 8960

$$

Britt
2 follow-up statements
052 
WGUS73 KLSX 150624
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
124 AM CDT SUN JUL 15 2018

ILC157-150900-
/O.CON.KLSX.FF.W.0024.000000T0000Z-180715T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Randolph IL-
124 AM CDT SUN JUL 15 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 400 AM CDT FOR
EASTERN RANDOLPH COUNTY...

At 122 AM CDT, Doppler radar indicated thunderstorms had produced 2 
to locally 4 inches of rainfall. Additional moderate rainfall was 
moving into the region. Flash flooding is either ongoing or could 
begin shortly.

Some locations that will experience flooding include...
Chester, Sparta, Bremen, Steeleville, Percy, Eden, Preston, Blair,
Houston, Rockwood, Walsh, Welge, New Palestine and Shiloh Hill.

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 3785 8966 3783 8966 3782 8968 3780 8968
      3782 8971 3785 8974 3785 8979 3787 8980
      3788 8980 3791 8984 3787 8990 3817 8985
      3816 8959 3795 8960

$$

KD
844 
WGUS73 KLSX 150824
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
324 AM CDT SUN JUL 15 2018

ILC157-150834-
/O.CAN.KLSX.FF.W.0024.000000T0000Z-180715T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Randolph IL-
324 AM CDT SUN JUL 15 2018

...THE FLASH FLOOD WARNING FOR EASTERN RANDOLPH COUNTY IS
CANCELLED...

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

LAT...LON 3785 8966 3783 8966 3782 8968 3780 8968
      3782 8971 3785 8974 3785 8979 3787 8980
      3788 8980 3791 8984 3787 8990 3817 8985
      3816 8959 3795 8960

$$

KD

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 7:32 PM CDTSpecial Weather StatementLSXWashington43 min
Jul 15, 3:15 PM CDTFlash Flood WarningLSXRandolph6 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.