Alert archive / Iowa / Flash Flood Warnings in 2017

Flash Flood Warning 19, NWS La Crosse, WI

July 21, 2017Chickasaw County, Clayton County, Fayette County, Iowa

NWS La Crosse, WI issued this flash flood warning at Jul 21, 2017, 10:18 PM CDT for Chickasaw County, Clayton County, Fayette County, Iowa. It was in force for 12 hr. 18 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: Jul 21, 2017, 10:18 PM CDT (03:18 UTC)
Expired: Jul 22, 2017, 10:15 AM CDT
In force: 12 hr
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Flood severity: None

Counties Chickasaw County, IA, Clayton County, IA, Fayette County, IA

The radar

The La Crosse radar (KARX), 129 km from the middle of the area, began a volume at 03:19 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
Jul 22, 1:51 AM CDT	FLASH FLOOD	1 E Fredericksburg, IA	WATER WAS REPORTED OVER HIGHWAY 18. SANDBAGGING WAS ONGOING IN NEW HAMPTON.
Jul 22, 1:51 AM CDT	FLASH FLOOD	1 Ene Fredericksburg, IA	WATER WAS REPORTED OVER HIGHWAY 18. SANDBAGGING WAS ONGOING IN NEW HAMPTON.
Jul 22, 3:28 AM CDT	HEAVY RAIN 10	Fredericksburg, IA	REPORT RELAYED BY BROADCAST MEDIA.
Jul 22, 6:00 AM CDT	HEAVY RAIN 5.15	1 Ene Volga, IA	CO-OP OBSERVER STATION VOLI4, VOLGA 1NE.
Jul 22, 6:21 AM CDT	HEAVY RAIN 7.5	2 Nnw Fayette, IA	STORM TOTAL.
Jul 22, 6:45 AM CDT	HEAVY RAIN 8.39	2 Sse Bassett, IA	CO-OP OBSERVER STATION IONI4, IONIA 2W.
Jul 22, 6:45 AM CDT	HEAVY RAIN 8.39	2 Wsw Ionia, IA	CO-OP OBSERVER STATION IONI4, IONIA 2W.
Jul 22, 6:55 AM CDT	HEAVY RAIN 2.63	3 W Oelwein, IA	AWOS STATION OLZ, OELWEIN MUNICIPAL AIRPORT.
Jul 22, 7:00 AM CDT	HEAVY RAIN 2.83	4 Wsw Saint Olaf, IA	MESONET STATION BSHI4, ELKADER 5NW.
Jul 22, 7:00 AM CDT	HEAVY RAIN 7.67	1 Nw Fayette, IA	CO-OP OBSERVER STATION FYTI4, FAYETTE.
Jul 22, 7:00 AM CDT	HEAVY RAIN 9.3	Ionia, IA
Jul 22, 7:24 AM CDT	HEAVY RAIN 5.44	1 N Nashua, IA
Jul 22, 7:35 AM CDT	HEAVY RAIN 5.63	Fayette, IA	MESONET STATION E2110, FAYETTE-CWOP.
Jul 22, 7:37 AM CDT	HEAVY RAIN 6.35	1 S New Hampton, IA
Jul 22, 7:37 AM CDT	HEAVY RAIN 6.35	1 Sse New Hampton, IA
Jul 22, 7:40 AM CDT	FLASH FLOOD	2 E Wadena, IA	BRIDGE GOING OVER THE VOLGA RIVER ON ACORN RD HAS FAILED.
Jul 22, 8:53 AM CDT	HEAVY RAIN 4.06	1 Wnw Oelwein, IA	STORM TOTAL.
Jul 22, 8:53 AM CDT	HEAVY RAIN 4.06	1 W Oelwein, IA	STORM TOTAL.

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 00:00Z, 3.3 hours before the alert went out and 260 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: 337 J/kg
Mixed-layer CIN: -126 J/kg
Mixed-layer LCL: 981 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 14 m²/s²
0-3 km storm-relative helicity: 40 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

850 
WGUS53 KARX 220318
FFWARX
IAC037-043-065-220915-
/O.NEW.KARX.FF.W.0019.170722T0318Z-170722T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service La Crosse WI
1018 PM CDT FRI JUL 21 2017

The National Weather Service in La Crosse has issued a

* Flash Flood Warning for...
  Southwestern Clayton County in northeastern Iowa...
  Fayette County in northeastern Iowa...
  Southern Chickasaw County in northeastern Iowa...

* Until 415 AM CDT

* At 1017 PM CDT, Doppler radar indicated thunderstorms producing 
  additional heavy rain across the warned area. 1 to 2 inches of new 
  rainfall has occurred over the past hour, with up to another 1 or 
  2 inches possible through early Saturday morning. Flash flooding 
  is expected to begin shortly if not already ongoing.

* Some locations that will experience flooding include...
  Oelwein, New Hampton, West Union, Nashua, Fayette, Strawberry
  Point, Fredericksburg, Elgin, Clermont, Maynard, Hawkeye,
  Arlington, Ionia, Volga, Chickasaw, Wadena, Westgate, Randalia,
  Bassett and Bradford.

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 4265 9190 4272 9208 4291 9208 4291 9255
      4307 9255 4300 9147 4264 9145

$$

Lawrence

4 follow-up statements

050 
WGUS73 KARX 220422
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
1122 PM CDT FRI JUL 21 2017

IAC037-043-065-220915-
/O.CON.KARX.FF.W.0019.000000T0000Z-170722T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clayton IA-Fayette IA-Chickasaw IA-
1122 PM CDT FRI JUL 21 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 AM CDT FOR
SOUTHWESTERN CLAYTON...FAYETTE AND SOUTHERN CHICKASAW COUNTIES...

At 1119 PM CDT, local law enforcement reported flash flooding 
ongoing across the area due to heavy rainfall, with many secondary 
roads experiencing flooding. An additional 1 to 2 inches of rain 
have fallen since 10 pm, with another 1 to 2 inches possible through 
early Saturday morning. Flash flooding will continue and may worsen.

Some locations that will experience flooding include...
Oelwein, New Hampton, West Union, Nashua, Fayette, Strawberry Point, 
Fredericksburg, Elgin, Clermont, Maynard, Hawkeye, Arlington, Ionia, 
Volga, Chickasaw, Wadena, Westgate, Randalia, Bassett and Bradford.

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 4265 9190 4272 9208 4291 9208 4291 9255
      4307 9255 4300 9147 4264 9145

$$

Lawrence

930 
WGUS73 KARX 220649
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
149 AM CDT SAT JUL 22 2017

IAC037-043-065-220915-
/O.CON.KARX.FF.W.0019.000000T0000Z-170722T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clayton IA-Fayette IA-Chickasaw IA-
149 AM CDT SAT JUL 22 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 AM CDT FOR
SOUTHWESTERN CLAYTON...FAYETTE AND SOUTHERN CHICKASAW COUNTIES...

At 147 AM CDT, local law enforcement reported flash flooding across 
the area. Numerous roads are closed across the area due to high 
water. Water was reported over highway 18 in Fredericksburg.

Some locations that will experience flooding include...
Oelwein, New Hampton, West Union, Nashua, Fayette, Strawberry Point,
Fredericksburg, Elgin, Clermont, Maynard, Hawkeye, Arlington, Ionia,
Volga, Chickasaw, Wadena, Westgate, Randalia, Bassett and Bradford.

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 4265 9190 4272 9208 4291 9208 4291 9255
      4307 9255 4300 9147 4264 9145

$$

Wetenkamp

812 
WGUS73 KARX 220752
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
252 AM CDT SAT JUL 22 2017

IAC037-043-065-220915-
/O.CON.KARX.FF.W.0019.000000T0000Z-170722T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clayton IA-Fayette IA-Chickasaw IA-
252 AM CDT SAT JUL 22 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 AM CDT FOR
SOUTHWESTERN CLAYTON...FAYETTE AND SOUTHERN CHICKASAW COUNTIES...

At 250 AM CDT, local law enforcement reported flash flooding across 
the area. Many roads are reported closed due to washouts or water 
flowing over them. The heaviest rain has shifted south of the area 
but flash flooding continues.  

Some locations that will experience flooding include...
Oelwein, New Hampton, West Union, Nashua, Fayette, Strawberry Point,
Fredericksburg, Elgin, Clermont, Maynard, Hawkeye, Arlington, Ionia,
Volga, Chickasaw, Wadena, Westgate, Randalia, Bassett and Bradford.

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 4265 9190 4272 9208 4291 9208 4291 9255
      4307 9255 4300 9147 4264 9145

$$

Wetenkamp

365 
WGUS53 KARX 220843
FFWARX
IAC037-043-065-221515-
/O.EXT.KARX.FF.W.0019.000000T0000Z-170722T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service La Crosse WI
343 AM CDT SAT JUL 22 2017

The National Weather Service in La Crosse has extended the

* Flash Flood Warning for...
  Southwestern Clayton County in northeastern Iowa...
  Fayette County in northeastern Iowa...
  Southern Chickasaw County in northeastern Iowa...

* Until 1015 AM CDT Saturday

* At 336 AM CDT, local law enforcement reported flash flooding 
  continuing across the area. Many roads are closed due to washouts 
  or water flowing over them. While rain has shifted south of the 
  area, flash flooding will continue through mid morning due to 
  excessive runoff from 5 to 10 inches of rain.

* Some locations that will experience flooding include...
  Oelwein, New Hampton, West Union, Nashua, Fayette, Strawberry
  Point, Fredericksburg, Elgin, Clermont, Maynard, Hawkeye,
  Arlington, Ionia, Volga, Chickasaw, Wadena, Westgate, Randalia,
  Bassett and Bradford.

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 4265 9190 4272 9208 4291 9208 4291 9255
      4307 9255 4300 9147 4264 9145

$$

Lawrence

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 9:06 PM CDT	River Flood Warning	ARX	Clayton	38 hr
Jul 21, 9:06 PM CDT	River Flood Warning	ARX	Clayton	63 hr
Jul 21, 11:54 PM CDT	Flash Flood Warning	ARX	Chickasaw, Floyd	10 hr
Jul 22, 1:21 AM CDT	Severe Thunderstorm Warning	ARX	Chickasaw, Howard, Winneshiek	39 min
Jul 22, 9:56 AM CDT	Areal Flood Warning	ARX	Clayton	24 hr
Jul 22, 10:09 AM CDT	Areal Flood Warning	ARX	Chickasaw, Clayton, Fayette	24 hr

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.