Alert archive / Illinois / Flash Flood Warnings in 2020

Flash Flood Warning 2, NWS Lincoln, IL

May 16, 2020Morgan County, Scott County, Illinois

NWS Lincoln, IL issued this flash flood warning at May 16, 2020, 2:45 PM CDT for Morgan County, Scott County, Illinois. It was in force for 4 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
May 16, 2020, 2:45 PM CDT (19:45 UTC)
Expired
May 16, 2020, 6:45 PM CDT
In force
4 hr
Issued by
NWS Lincoln, IL
Area
Storm-based polygon
Flood severity
None

Counties Morgan County, IL, Scott County, IL

The radar

The St Louis radar (KLSX), 104 km from the middle of the area, began a volume at 19:46 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
May 16, 3:00 PM CDTFLASH FLOODManchester, ILDELAYED REPORT. A VIADUCT AND SEVERAL STREETS IN TOWN FLOODED. FLOODING HAS SUBSIDED AS OF 630 PM.
May 16, 6:35 PM CDTFLOODMurrayville, ILEXTENSIVE FLOODING ON AREA ROADS FROM MURRAYVILLE TO THE SCOTT-MORGAN COUNTY LINE DUE TO EARLIER RAINFALL OF 2.50 TO 3.50 INCHES.

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 12:00Z, 7.8 hours before the alert went out and 164 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 12:00Z on 2020-05-16Temperature 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, Lincoln, IL at 12:00Z on 2020-05-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
818 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

902 
WGUS53 KILX 161945
FFWILX
ILC137-171-162345-
/O.NEW.KILX.FF.W.0002.200516T1945Z-200516T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lincoln IL
245 PM CDT Sat May 16 2020

The National Weather Service in Lincoln has issued a

* Flash Flood Warning for...
  Southeastern Scott County in west central Illinois...
  South central Morgan County in west central Illinois...

* Until 645 PM CDT.

* At 241 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area moving slowly north at 15 mph. 
  Radar estimated up to 1.5 to 2.5 inches of rain have already 
  fallen in past hour in far southeast Scott and far southwest 
  Morgan counties. Betweeen 1.5 to 3 inches of additional rain is 
  expected by 4 pm over parts of southeast Scott and southern and 
  southwest Morgan counties. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  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 flooding include...
  Jacksonville, Winchester, Murrayville, Woodson, Manchester, Alsey,
  South Jacksonville, Glasgow, Nortonville and Lake Jacksonville.

This includes Interstate 72 between mile markers 60 and 68.
 
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 3964 9055 3972 9012 3952 9015 3952 9056

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR

$$

07
1 follow-up statement
760 
WGUS73 KILX 162139
FFSILX

Flash Flood Statement
National Weather Service Lincoln IL
439 PM CDT Sat May 16 2020

ILC137-171-162345-
/O.CON.KILX.FF.W.0002.000000T0000Z-200516T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Scott-Morgan-
439 PM CDT Sat May 16 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR
SOUTHEASTERN SCOTT AND SOUTH CENTRAL MORGAN COUNTIES...

At 434 PM CDT, Doppler radar indicated thunderstorms producing rain 
across the warned area. Radar estimated rainfall totals since 230 pm 
ranged from 1 to 2 inches in southwest Scott County, to 3 to 4 
inches from Manchester toward Murrayville.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

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 flooding include...
Murrayville, Manchester and Woodson.

This also includes Interstate 72 between mile markers 65 and 67.
 
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 3960 9052 3972 9012 3952 9015 3952 9056

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5 to 1.0 INCH THROUGH 6 PM!

$$

Miller

The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 2:26 PM CDTSpecial Weather StatementILXMorgan, Scott49 min
May 16, 3:14 PM CDTSpecial Weather StatementILXMorgan46 min
May 16, 3:34 PM CDTSpecial Weather StatementILXMorgan41 min
May 16, 3:50 PM CDTFlash Flood WarningILXMorgan, Sangamon4 hr
May 16, 6:49 PM CDTAreal Flood WarningILXMorgan, Scott12 hr

Nearby

Flash Flood Warnings in Illinois, 2020Every flash flood warning in 2020

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.