Alert archive / Iowa / Flash Flood Warnings in 2018

Flash Flood Warning 13, NWS Des Moines, IA

June 24, 2018Hancock County, Winnebago County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 24, 2018, 6:29 PM CDT for Hancock County, Winnebago County, Iowa. It was in force for 13 hr. 3 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
Jun 24, 2018, 6:29 PM CDT (23:29 UTC)
Expired
Jun 25, 2018, 7:42 AM CDT
In force
13 hr
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Flood severity
None

Counties Hancock County, IA, Winnebago County, IA

The radar

The Minneapolis radar (KMPX), 169 km from the middle of the area, began a volume at 23:30 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
Jun 24, 6:30 PM CDTFLASH FLOODForest City, IA2-3 FT OF WATER OVER HWY 9 AND HWY 69 IN FOREST CITY - CLOSING ROADS.
Jun 24, 11:33 PM CDTHEAVY RAIN 42 W Forest City, IAVIA SOCIAL MEDIA.
Jun 25, 7:00 AM CDTHEAVY RAIN 2.882 N Forest City, IA

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.5 hours before the alert went out and 169 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, Minneapolis, MN at 12:00Z on 2018-06-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 216 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, Minneapolis, MN at 12:00Z on 2018-06-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -26 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
216 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
1065 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

185 
WGUS53 KDMX 242329
FFWDMX
IAC081-189-250530-
/O.NEW.KDMX.FF.W.0013.180624T2329Z-180625T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
629 PM CDT SUN JUN 24 2018

The National Weather Service in Des Moines  has issued a

* Flash Flood Warning for...
  Northeastern Hancock County in north central Iowa...
  Winnebago County in north central Iowa...

* Until 1230 AM CDT Monday.

* At 627 PM CDT, emergency management reported Highway 69 and 
  Highway 9 in Forest City under 2 to 3 feet. Heavy rainfall is 
  causing flash flooding or will cause flash flooding soon.

* Some locations that will experience flooding include...
  Forest City, Lake Mills, Thompson, Leland, Crystal Lake, Rake,
  Scarville, Miller, Hayfield, Pilot Knob State Park and Forest City
  Municipal Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4334 9350 4315 9350 4316 9384 4350 9396
      4350 9359

$$

Ansorge
3 follow-up statements
884 
WGUS53 KDMX 250459
FFWDMX
IAC081-189-251330-
/O.EXT.KDMX.FF.W.0013.000000T0000Z-180625T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
1159 PM CDT SUN JUN 24 2018

The National Weather Service in Des Moines  has extended the

* Flash Flood Warning for...
  Northeastern Hancock County in north central Iowa...
  Winnebago County in north central Iowa...

* Until 830 AM CDT Monday.

* At 1155 PM CDT, local law enforcement continued flash flooding 
  across the county with numerous roads flooded in Forest City and 
  Thompson. Moderate rainfall is still occurring across the warned 
  area with another half inch to inch of rainfall possible in the 
  next few hours. Flash flooding is already occurring.

* Some locations that will experience flooding include...
  Forest City, Lake Mills, Thompson, Leland, Crystal Lake, Rake,
  Scarville, Miller, Hayfield, Pilot Knob State Park and Forest City
  Municipal Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles. Nighttime flooding is especially 
dangerous.  Stay away from flooded areas and move to higher ground 
if flooding is occurring or you live in a flood prone area. 


&&

LAT...LON 4334 9350 4315 9350 4316 9384 4350 9396
      4350 9359

$$

REV
313 
WGUS73 KDMX 250930
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
430 AM CDT MON JUN 25 2018

IAC081-189-251330-
/O.CON.KDMX.FF.W.0013.000000T0000Z-180625T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hancock IA-Winnebago IA-
430 AM CDT MON JUN 25 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 AM CDT FOR
NORTHEASTERN HANCOCK AND WINNEBAGO COUNTIES...

At 428 AM CDT, flooding continues over the warned counties. If you 
plan on traveling early this Monday morning, use extreme caution and 
avoid flooded areas. Many roads across the counties have been 
affected by last night's heavy rainfall and conditions will be slow 
to improve this morning. 

Some locations that will experience flooding include...
Forest City, Lake Mills, Thompson, Leland, Crystal Lake, Rake,
Scarville, Miller, Hayfield, Pilot Knob State Park and Forest City
Municipal Airport.

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 4334 9350 4315 9350 4316 9384 4350 9396
      4350 9359

$$

REV
779 
WGUS73 KDMX 251242
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
742 AM CDT MON JUN 25 2018

IAC081-189-251252-
/O.CAN.KDMX.FF.W.0013.000000T0000Z-180625T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hancock IA-Winnebago IA-
742 AM CDT MON JUN 25 2018

...THE FLASH FLOOD WARNING FOR NORTHEASTERN HANCOCK AND WINNEBAGO
COUNTIES IS CANCELLED...

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

LAT...LON 4334 9350 4315 9350 4316 9384 4350 9396
      4350 9359

$$

Johnson

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 24, 2:31 PM CDTSpecial Weather StatementDMXSac59 min
Jun 24, 2:40 PM CDTSpecial Weather StatementDMXGuthrie, Madison65 min
Jun 24, 2:52 PM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison38 min
Jun 24, 3:19 PM CDTSevere Thunderstorm WarningDMXCarroll, Greene, Guthrie41 min
Jun 24, 3:40 PM CDTSpecial Weather StatementDMXWarren65 min
Jun 24, 4:00 PM CDTSevere Thunderstorm WarningDMXCarroll, Sac45 min
Jun 24, 4:24 PM CDTSevere Thunderstorm WarningDMXCalhoun, Carroll, Greene, Sac33 min
Jun 24, 5:48 PM CDTSevere Thunderstorm WarningDMXEmmet42 min
Jun 24, 6:12 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock, Winnebago27 min

Nearby

Flash Flood Warnings in Iowa, 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.