Alert archive / Iowa / Flash Flood Warnings in 2018

Flash Flood Warning 2, NWS Des Moines, IA

June 8, 2018Cerro Gordo County, Worth County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 8, 2018, 8:01 AM CDT for Cerro Gordo County, Worth County, Iowa. It was in force for 6 hr. 6 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 8, 2018, 8:01 AM CDT (13:01 UTC)
Expired: Jun 8, 2018, 2:00 PM CDT
In force: 6 hr
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Flood severity: None

Counties Cerro Gordo County, IA, Worth County, IA

The radar

The Des Moines radar (KDMX), 157 km from the middle of the area, began a volume at 13:03 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.

What was reported inside it

Time	Report	Where	Remark
Jun 8, 8:40 AM CDT	HEAVY RAIN 3.65	4 Wsw Plymouth, IA	3.65 INCHES FROM 3:20A TO 8:25A; 24 HOUR RAIN TOTAL AS OF 8:25A IS 4.06 INCHES.
Jun 8, 8:50 AM CDT	HEAVY RAIN 5	Manly, IA	VIA SOCIAL MEDIA.
Jun 8, 8:51 AM CDT	HEAVY RAIN 4.7	1 Ese Mason City, IA	THIS IS AN UPDATED TOTAL FROM A 615A STORM REPORT, WHICH HAD 3.75.
Jun 8, 9:35 AM CDT	HEAVY RAIN 3.18	Grafton, IA
Jun 8, 10:20 AM CDT	FLASH FLOOD	3 Wsw Manly, IA	SEVERAL COUNTY GRAVEL ROADS ARE CLOSED AROUND THE TOWN OF MANLY WITH ONE ROAD WASHED OUT SOUTH OF HIGHWAY 9 ON MALLARD AVENUE.
Jun 8, 11:42 AM CDT	HEAVY RAIN 5.6	Mason City, IA	FROM KIMT-TV STUDIO.

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, 1.0 hours before the alert went out and 198 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 957 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

787 
WGUS53 KDMX 081301
FFWDMX
IAC033-195-081900-
/O.NEW.KDMX.FF.W.0002.180608T1301Z-180608T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
801 AM CDT FRI JUN 8 2018

The National Weather Service in Des Moines  has issued a

* Flash Flood Warning for...
  Southern Worth County in north central Iowa...
  Cerro Gordo County in north central Iowa...

* Until 200 PM CDT Friday.

* At 757 AM CDT, local law enforcement reported thunderstorms 
  producing heavy rain across the warned area. Widespread 2 to 3 
  inch rainfall totals with isolated 4 inch totals from automated 
  gauges. Worth County Sheriff has reported Iowa Highway 9 closed 
  west of Manly with water moving quickly across the road. 
  Additional rainfall of half an inch to an inch is expected in the 
  next few hours. Flash flooding is occurring or expected to begin 
  shortly.

* Some locations that will experience flooding include...
  Mason City, Nora Springs, Manly, Rockwell, Mason City Municipal
  Airport, Clear Lake, Ventura, Thornton, Plymouth, Fertile, Kensett,
  Meservey, Grafton, Hanlontown, Swaledale, Rock Falls, Burchinal,
  Portland, Bolan and McIntosh Woods State Park.

This includes Interstate 35 between mile markers 178 and 209.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4307 9302 4297 9314 4291 9329 4291 9350
      4335 9349 4339 9302

$$

Ansorge

2 follow-up statements

527 
WGUS73 KDMX 081528
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
1028 AM CDT FRI JUN 8 2018

IAC033-195-081900-
/O.CON.KDMX.FF.W.0002.000000T0000Z-180608T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Worth IA-Cerro Gordo IA-
1028 AM CDT FRI JUN 8 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 200 PM CDT FOR
SOUTHERN WORTH AND CERRO GORDO COUNTIES...

At 1020 AM CDT, local law enforcement reported several county roads 
closed with a few county roads washed out. Widespread 2 to 4 inches 
of rain has fallen over this area with isolated amounts around 5 
inches. Flash flooding is occurring in some locations already. Rain 
is beginning to end over the western part of the warned area and 
will end in the next hour or so over the rest of the warned area. 
Despite this, flooding may continue until later this morning or 
early this afternoon.

Some locations that will experience flooding include...
Mason City, Nora Springs, Manly, Rockwell, Mason City Municipal
Airport, Clear Lake, Ventura, Thornton, Plymouth, Fertile, Kensett,
Meservey, Grafton, Hanlontown, Swaledale, Rock Falls, Burchinal,
Portland, Bolan and McIntosh Woods State Park.

This includes Interstate 35 between mile markers 178 and 209.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4307 9302 4297 9314 4291 9329 4291 9350
      4335 9349 4339 9302

$$

Ansorge

800 
WGUS73 KDMX 081852
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
152 PM CDT FRI JUN 8 2018

IAC033-195-081900-
/O.EXP.KDMX.FF.W.0002.000000T0000Z-180608T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Worth IA-Cerro Gordo IA-
152 PM CDT FRI JUN 8 2018

...THE FLASH FLOOD WARNING FOR SOUTHERN WORTH AND CERRO GORDO
COUNTIES WILL EXPIRE AT 200 PM CDT...

Flash flooding has ended over southern Worth County, but flooding 
remains a concern over Cerro Gordo. Therefore, the Flash Flood 
Warning has been replaced with an Areal Flood Warning for Cerro 
Gordo County. Please continue to heed any remaining road closures 
and remember if you come across a flooded roadway, turn around, 
don't drown.

LAT...LON 4307 9302 4297 9314 4291 9329 4291 9350
      4335 9349 4339 9302

$$

Ansorge

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 7, 9:03 PM CDT	Special Weather Statement	DMX	Worth	57 min
Jun 7, 9:14 PM CDT	Severe Thunderstorm Warning	DMX	Worth	46 min
Jun 8, 3:38 AM CDT	Special Weather Statement	DMX	Winnebago	52 min
Jun 8, 6:24 AM CDT	Special Weather Statement	DMX	Cerro Gordo, Worth	66 min
Jun 8, 6:43 AM CDT	Special Weather Statement	DMX	Hancock, Kossuth, Palo Alto, Winnebago	47 min
Jun 8, 1:40 PM CDT	Areal Flood Warning	DMX	Cerro Gordo	21 hr
Jun 8, 2:02 PM CDT	River Flood Warning	DMX	Cerro Gordo, Floyd, Worth	4 hr
Jun 8, 2:02 PM CDT	Severe Thunderstorm Warning	DMX	Davis, Wapello	13 min
Jun 8, 2:11 PM CDT	River Flood Watch	DMX	Black Hawk	40 hr
Jun 8, 3:02 PM CDT	Severe Thunderstorm Warning	DMX	Sac	43 min
Jun 8, 3:46 PM CDT	Special Weather Statement	DMX	Sac	29 min

Nearby

Flash Flood Warnings in Iowa, 2018 Every 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.