Alert archive / Iowa / Flash Flood Warnings in 2017

Flash Flood Warning 1, NWS Des Moines, IA

May 15, 20174 counties in Iowa

NWS Des Moines, IA issued this flash flood warning at May 15, 2017, 6:24 PM CDT for 4 counties in Iowa. 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: May 15, 2017, 6:24 PM CDT (23:24 UTC)
Expired: May 16, 2017, 12:30 AM CDT
In force: 6 hr
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Flood severity: None

Counties Cerro Gordo County, IA, Franklin County, IA, Hancock County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 136 km from the middle of the area, began a volume at 23:25 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
May 15, 7:30 PM CDT	FLASH FLOOD	4 Se Klemme, IA	VAIL AVE WAS REPORTED TO BE WASHED OUT JUST SOUTH OF 140TH ST.

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, 11.4 hours before the alert went out and 216 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: 4 J/kg
Mixed-layer CIN: -548 J/kg
Mixed-layer LCL: 1538 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 136 m²/s²
0-3 km storm-relative helicity: 125 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

581 
WGUS53 KDMX 152324
FFWDMX
IAC033-069-081-197-160530-
/O.NEW.KDMX.FF.W.0001.170515T2324Z-170516T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
624 PM CDT MON MAY 15 2017

The National Weather Service in Des Moines  has issued a

* Flash Flood Warning for...
  Northern Franklin County in north central Iowa...
  Northeastern Wright County in north central Iowa...
  Southeastern Hancock County in north central Iowa...
  Southern Cerro Gordo County in north central Iowa...

* Until 1230 AM CDT Tuesday.

* At 622 PM CDT, trained weather spotters reported flash flooding 
  across the warned area. Two to three inches of rain have already 
  fallen. Flash flooding is already occurring. Two feet of fast 
  rushing water was reported flowing across Indigo Ave west of 
  Swaledale near County Road B60. 

* Some locations that will experience flooding include...
  Hampton, Belmond, Sheffield, Rockwell, Elm Lake, Kanawha, Latimer,
  Thornton, Coulter, Meservey, Alexander, Swaledale, Rowan, Goodell,
  Hansell, Chapin, Dougherty, Beeds Lake State Park and Belmond
  Municipal Airport.

Additional rainfall amounts of a half an inch to as much as one inch 
are possible in the warned area.

This includes Interstate 35 between mile markers 166 and 187.
 
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 4304 9302 4273 9303 4274 9367 4293 9382
      4305 9339

$$

Beerends

2 follow-up statements

006 
WGUS73 KDMX 160142
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
842 PM CDT MON MAY 15 2017

IAC033-069-081-197-160530-
/O.CON.KDMX.FF.W.0001.000000T0000Z-170516T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Franklin IA-Wright IA-Hancock IA-Cerro Gordo IA-
842 PM CDT MON MAY 15 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT FOR
NORTHERN FRANKLIN...NORTHEASTERN WRIGHT...SOUTHEASTERN HANCOCK AND
SOUTHERN CERRO GORDO COUNTIES...

At 838 PM CDT, trained weather spotters reported flash flooding 
across portions of the warned area. Up to three inches of rain have 
already fallen. Flash flooding is already occurring. Vail Ave. or 
County Road R66 was washed out south of 140th Street in southeastern 
Hancock County.  

Some locations that will experience flooding include...
Hampton, Belmond, Sheffield, Rockwell, Elm Lake, Kanawha, Latimer,
Thornton, Coulter, Meservey, Alexander, Swaledale, Rowan, Goodell,
Hansell, Chapin, Dougherty, Beeds Lake State Park and Belmond
Municipal Airport.

This includes Interstate 35 between mile markers 166 and 187.
 
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 4304 9302 4273 9303 4274 9367 4293 9382
      4305 9339

$$

Beerends

959 
WGUS73 KDMX 160525
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
1225 AM CDT TUE MAY 16 2017

IAC033-069-081-197-160535-
/O.EXP.KDMX.FF.W.0001.000000T0000Z-170516T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Franklin IA-Wright IA-Hancock IA-Cerro Gordo IA-
1225 AM CDT TUE MAY 16 2017

...THE FLASH FLOOD WARNING FOR NORTHERN FRANKLIN...NORTHEASTERN
WRIGHT...SOUTHEASTERN HANCOCK AND SOUTHERN CERRO GORDO COUNTIES WILL
EXPIRE AT 1230 AM CDT...

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 4304 9302 4273 9303 4274 9367 4293 9382
      4305 9339

$$

Cogil

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 12:19 PM CDT	Special Weather Statement	DMX	Hamilton	56 min
May 15, 12:58 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Greene, Hamilton, Webster	47 min
May 15, 1:44 PM CDT	Special Weather Statement	DMX	Hardin	46 min
May 15, 3:42 PM CDT	Severe Thunderstorm Warning	DMX	Worth	18 min
May 15, 4:20 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Kossuth	40 min
May 15, 4:53 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt, Kossuth, Pocahontas	27 min
May 15, 4:58 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Hancock	23 min
May 15, 5:19 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Franklin, Hancock, Humboldt, Wright	41 min
May 15, 5:58 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Cerro Gordo, Franklin, Wright	47 min
May 15, 6:31 PM CDT	Severe Thunderstorm Warning	DMX	Bremer, Butler	44 min
May 15, 6:41 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Franklin	34 min

Nearby

Flash Flood Warnings in Iowa, 2017 Every flash flood warning in 2017

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.