Alert archive / Illinois / Flash Flood Warnings in 2018

Flash Flood Warning 21, NWS St. Louis, MO

June 28, 2018Monroe County, Randolph County, Illinois; Jefferson County, Missouri

NWS St. Louis, MO issued this flash flood warning at Jun 28, 2018, 8:07 PM CDT for Monroe County, Randolph County, Illinois; Jefferson County, Missouri. It was in force for 6 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
Jun 28, 2018, 8:07 PM CDT (01:07 UTC)
Expired
Jun 29, 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, Randolph County, IL, Jefferson County, MO

The radar

The St Louis radar (KLSX), 85 km from the middle of the area, began a volume at 01:09 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, 1.1 hours before the alert went out and 267 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 2018-06-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1599 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 2018-06-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 55 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
1599 J/kg
Mixed-layer CIN
-203 J/kg
Mixed-layer LCL
1432 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted.

925 
WGUS53 KLSX 290107
FFWLSX
ILC133-157-MOC099-290700-
/O.NEW.KLSX.FF.W.0021.180629T0107Z-180629T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service St Louis MO
807 PM CDT THU JUN 28 2018

The National Weather Service in St Louis has issued a

* Flash Flood Warning for...
  Monroe County in southwestern Illinois...
  Randolph County in southwestern Illinois...
  Jefferson County in east central Missouri...

* Until 200 AM CDT.

* At 806 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is expected to
  begin shortly. 

* Some locations that will experience flooding include...
  Festus, Waterloo, Chester, De Soto, Pevely, Crystal City, Sparta,
  Red Bud, Herculaneum, Hillsboro, Antonia, Barnhart, Cedar Hill,
  Bremen, Steeleville, Valmeyer, Percy, Coulterville, Tilden and
  Olympian Village.

This includes Interstate 55 in Missouri between exits 170 and 187.
 
This also includes  Mastodon Historic Site, Sandy Creek Covered
Bridge Historic Site, and Gov. Dunklin's Grave Historic Site.
 
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 3795 8960 3782 8968 3785 8979 3791 8984
      3788 8994 3793 8998 3796 8992 3797 9000
      3813 9025 3804 9041 3801 9061 3807 9061
      3810 9065 3809 9068 3821 9077 3840 9073
      3838 9010 3831 9004 3822 8990 3822 8959

$$

Glass
1 follow-up statement
107 
WGUS73 KLSX 290657
FFSLSX

Flash Flood Statement
National Weather Service St Louis MO
157 AM CDT FRI JUN 29 2018

ILC133-157-MOC099-290707-
/O.EXP.KLSX.FF.W.0021.000000T0000Z-180629T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe IL-Randolph IL-Jefferson MO-
157 AM CDT FRI JUN 29 2018

...THE FLASH FLOOD WARNING FOR MONROE...RANDOLPH AND JEFFERSON
COUNTIES WILL EXPIRE AT 200 AM CDT...

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

LAT...LON 3795 8960 3782 8968 3785 8979 3791 8984
      3788 8994 3793 8998 3796 8992 3797 9000
      3813 9025 3804 9041 3801 9061 3807 9061
      3810 9065 3809 9068 3821 9077 3840 9073
      3838 9010 3831 9004 3822 8990 3822 8959

$$

KD

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 7:24 PM CDTFlash Flood WarningLSXClinton, Monroe, Saint Clair, Washington4 hr
Jun 28, 7:38 PM CDTSpecial Weather StatementLSXJefferson37 min
Jun 28, 8:41 PM CDTSpecial Weather StatementLSXSaint Francois, Washington49 min
Jun 28, 8:51 PM CDTFlash Flood WarningLSXSainte Genevieve, Saint Francois6 hr
Jun 28, 9:49 PM CDTSpecial Weather StatementLSXIron41 min

Nearby

Flash Flood Warnings in Illinois, 2018Flash Flood Warnings in Missouri, 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.