Alert archive / Illinois / Flash Flood Warnings in 2014

Flash Flood Warning 21, NWS Chicago, IL

August 1, 2014Ogle County, Winnebago County, Illinois

NWS Chicago, IL issued this flash flood warning at Aug 1, 2014, 8:05 PM CDT for Ogle County, Winnebago 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
Aug 1, 2014, 8:05 PM CDT (01:05 UTC)
Expired
Aug 2, 2014, 2:00 AM CDT
In force
6 hr
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Flood severity
None

Counties Ogle County, IL, Winnebago County, IL

The radar

The Milwaukee radar (KMKX), 90 km from the middle of the area, began a volume at 01:07 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
Aug 1, 9:00 PM CDTHEAVY RAIN 1.35Rockford Airport, IL

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 00:00Z, 1.1 hours before the alert went out and 139 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 00:00Z on 2014-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 722 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, Davenport, at 00:00Z on 2014-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
722 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
1694 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
-5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

596 
WGUS53 KLOT 020105
FFWLOT
ILC141-201-020700-
/O.NEW.KLOT.FF.W.0021.140802T0105Z-140802T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
805 PM CDT FRI AUG 1 2014

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN OGLE COUNTY IN NORTH CENTRAL ILLINOIS...
  SOUTHEASTERN WINNEBAGO COUNTY IN NORTH CENTRAL ILLINOIS...

* UNTIL 200 AM CDT

* AT 804 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE
  WARNED AREA. RADAR ESTIMATES THAT IN EXCESS OF TWO INCHES OF RAIN  
  HAS FALLEN IN PARTS OF THE WARNING AREA.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  ROCKFORD...ROCKFORD AIRPORT AND CHERRY VALLEY.

ROCKFORD POLICE DEPARTMENT REPORTED UP TO ONE FOOT OF STANDING WATER 
ON SOME ROADS IN ROCKFORD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 4232 8894 4211 8894 4212 8918 4233 8918

$$

RC
2 follow-up statements
027 
WGUS73 KLOT 020207
FFSLOT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
907 PM CDT FRI AUG 1 2014

ILC141-201-020700-
/O.CON.KLOT.FF.W.0021.000000T0000Z-140802T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
OGLE IL-WINNEBAGO IL-
907 PM CDT FRI AUG 1 2014

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHEASTERN WINNEBAGO
AND NORTHEASTERN OGLE COUNTIES UNTIL 200 AM CDT...

RADAR INDICATES THAT SOME AREAS MAY HAVE SEEN SLIGHTLY IN EXCESS OF 
TWO INCHES OF RAIN IN THUNDERSTORMS THAT HAVE NOW MOVED SOUTH OF THE 
WARNED AREA.

EMERGENCY MANAGERS AND LAW ENFORCEMENT REPORTED THAT MINOR FLOODING 
WAS OCCURRING ON MANY ROADS IN THE CENTER OF ROCKFORD BETWEEN 8 PM 
AND 830 PM.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...ROCKFORD...
ROCKFORD AIRPORT AND CHERRY VALLEY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND. DO NOT
STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN 
DEPTH BY FOOT OR BY AUTOMOBILE.

&&

LAT...LON 4232 8894 4211 8894 4212 8918 4233 8918

$$

RC
117 
WGUS73 KLOT 020258
FFSLOT

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
958 PM CDT FRI AUG 1 2014

ILC141-201-020313-
/O.CAN.KLOT.FF.W.0021.000000T0000Z-140802T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
OGLE IL-WINNEBAGO IL-
958 PM CDT FRI AUG 1 2014

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHEASTERN
WINNEBAGO AND NORTHEASTERN OGLE COUNTIES IS CANCELLED...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

&&

LAT...LON 4232 8894 4211 8894 4212 8918 4233 8918

$$

RC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 7:19 PM CDTSevere Thunderstorm WarningLOTDeKalb7 min
Aug 1, 7:24 PM CDTSevere Thunderstorm WarningLOTWinnebago21 min
Aug 1, 7:30 PM CDTAreal Flood AdvisoryLOTOgle, Winnebago6 hr
Aug 1, 7:55 PM CDTAreal Flood AdvisoryLOTBoone, Lake, McHenry3 hr

Nearby

Flash Flood Warnings in Illinois, 2014Every flash flood warning in 2014

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.