Alert archive / Iowa / Flash Flood Warnings in 2017

Flash Flood Warning 5, NWS Des Moines, IA

July 21, 2017Bremer County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jul 21, 2017, 10:24 PM CDT for Bremer County, Iowa. It was in force for 15 hr. 4 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, 10:24 PM CDT (03:24 UTC)
Expired
Jul 22, 2017, 1:45 PM CDT
In force
15 hr
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Flood severity
None

County Bremer County, IA

The radar

The La Crosse radar (KARX), 140 km from the middle of the area, began a volume at 03:24 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
Jul 22, 1:35 AM CDTFLASH FLOOD1 W Sumner, IAREPORTS OF SEVERAL HOUSES WITH WATER FLOODING INTO BASEMENTS. NUMEROUS ROADS COVERED WITH WATER UP TO ONE FOOT IN PLACES. AT LEAST ONE PERSON BEING EVACUATED FROM HOME.
Jul 22, 4:00 AM CDTFLASH FLOOD1 Nw Sumner, IAUP TO A DOZEN EVACUATIONS FROM HIGH WATER AROUND THE SUMNER AREA. MULTIPLE ROAD CLOSURES AS WELL.
Jul 22, 5:41 AM CDTFLASH FLOOD2 W Sumner, IAIDOT REPORTS IA 93 BETWEEN COUNTY ROAD V48 (NEAR TRIPOLI) AND COUNTY ROAD V68 (NEAR SUMNER) IS BLOCKED DUE TO FLOODING.
Jul 22, 5:42 AM CDTFLASH FLOODSumner, IATOTAL EVACUATIONS IN SUMNER NOW 15-18 PEOPLE. NUMEROUS ROADS CONTINUE TO BE UNDERWATER. ELECTRICAL POWER IN SUMNER HAS BEEN INTERRUPTED AS WELL.

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, 3.4 hours before the alert went out and 251 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 00:00Z on 2017-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 337 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 00:00Z on 2017-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.19395878Sfc1 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
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.

356 
WGUS53 KDMX 220324
FFWDMX
IAC017-220930-
/O.NEW.KDMX.FF.W.0005.170722T0324Z-170722T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
1024 PM CDT FRI JUL 21 2017

The National Weather Service in Des Moines  has issued a

* Flash Flood Warning for...
  Northeastern Bremer County in northeastern Iowa...

* Until 430 AM CDT Saturday.

* At 1024 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is expected to
  begin shortly.

* Some locations that will experience flooding include...
  Sumner, Tripoli and Frederika. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Lee
6 follow-up statements
931 
WGUS73 KDMX 220649
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
149 AM CDT SAT JUL 22 2017

IAC017-220930-
/O.CON.KDMX.FF.W.0005.000000T0000Z-170722T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bremer IA-
149 AM CDT SAT JUL 22 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 AM CDT FOR
NORTHEASTERN BREMER COUNTY...

At 143 AM CDT, Doppler radar indicated thunderstorms producing very 
heavy rain across the warned area. Radar estimated rainfall of up to 
three to four inches of rain have already fallen since 10 PM Friday 
night and additional very heavy rain is expected to persist through 
the morning hours. At 140 AM CDT, local law enforcement reported 
several roads in the warned area being inundated with flowing water 
and the hardest hit area has been in and around Sumner in far 
northeast Bremer County.  However other locations likely to 
experience flash flooding include...Tripoli and Frederika. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Flash Flooding is occurring or is imminent. It is important to know 
where you are relative to streams, rivers, or creeks which can 
become killers in heavy rains. Campers and hikers should avoid 
streams or creeks.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Podrazik
850 
WGUS53 KDMX 220916
FFWDMX
IAC017-221300-
/O.EXT.KDMX.FF.W.0005.000000T0000Z-170722T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
416 AM CDT SAT JUL 22 2017

The National Weather Service in Des Moines  has extended the

* Flash Flood Warning for...
  Northeastern Bremer County in northeastern Iowa...

* Until 800 AM CDT.

* At 400 AM CDT, emergency management reported multiple evacuations 
  in the Sumner area along with several road closures due to high 
  water throughout the county. Radar estimated up to three to four 
  inches of rain have already fallen in addition to what accumulated 
  early Friday morning. Flash flooding is already occurring and is 
  expected to persist through the morning hours.

* Locations that will experience flooding include...Sumner, 
  Tripoli and Frederika. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Podrazik
424 
WGUS73 KDMX 221101
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
601 AM CDT SAT JUL 22 2017

IAC017-221300-
/O.CON.KDMX.FF.W.0005.000000T0000Z-170722T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bremer IA-
601 AM CDT SAT JUL 22 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 AM CDT FOR
NORTHEASTERN BREMER COUNTY...

At 558 AM CDT, emergency management reported flash flooding in 
Sumner as well as throughout much of northeast Bremer County. At 542 
AM CDT, emergency management reported multiple evacuations have 
occurred in Sumner as well as power being interrupted in town. 
Several roads in northeast Bremer County remain underwater. 

Additional locations that will experience flooding include... 
Tripoli and Frederika. 

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.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Podrazik
316 
WGUS53 KDMX 221250
FFWDMX
IAC017-221600-
/O.EXT.KDMX.FF.W.0005.000000T0000Z-170722T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
750 AM CDT SAT JUL 22 2017

The National Weather Service in Des Moines  has extended the

* Flash Flood Warning for...
  Northeastern Bremer County in northeastern Iowa...

* Until 1100 AM CDT.

* At 748 AM CDT, emergency management reported flash flooding 
  continues across much of northeast Bremer County. Many small 
  creeks continue to rise in and around Sumner.

* Locations experiencing flooding include...Sumner, 
  Tripoli and Frederika. 

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, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Podrazik
681 
WGUS53 KDMX 221555
FFWDMX
IAC017-221900-
/O.EXT.KDMX.FF.W.0005.000000T0000Z-170722T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
1055 AM CDT SAT JUL 22 2017

The National Weather Service in Des Moines  has extended the

* Flash Flood Warning for...
  Northeastern Bremer County in northeastern Iowa...

* Until 200 PM CDT.

* At 1054 AM CDT, local law enforcement reported flash flooding 
  continues across much of northeast Bremer County. Many small 
  creeks continue to rise in and around Sumner.

* Some locations that will experience flooding include...
  Sumner, Tripoli and Frederika. 

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, urban areas, highways, streets and underpasses 
as well as other drainage areas and low lying spots.

&&

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Kotenberg
096 
WGUS73 KDMX 221845
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
145 PM CDT SAT JUL 22 2017

IAC017-221853-
/O.CAN.KDMX.FF.W.0005.000000T0000Z-170722T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bremer IA-
145 PM CDT SAT JUL 22 2017

...THE FLASH FLOOD WARNING FOR NORTHEASTERN BREMER COUNTY IS
CANCELLED...

The heavy rain has ended. However, local Emergency Management 
reports that several major roadways in northeastern Bremer County, 
including Highway 93 into Sumner, is still closed due to flooding. 
Please continue to heed any remaining road closures.

LAT...LON 4277 9228 4291 9246 4291 9208 4272 9208

$$

Kotenberg

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 9:58 PM CDTSpecial Weather StatementDMXBremer62 min
Jul 22, 2:04 AM CDTFlash Flood WarningDMXBlack Hawk, Bremer, Butler6 hr
Jul 22, 3:59 AM CDTHeat AdvisoryDMXAudubon, Cass, Guthrie16 hr
Jul 22, 7:56 AM CDTAreal Flood WarningDMXBremer24 hr
Jul 22, 2:19 PM CDTAreal Flood WarningDMXBremer24 hr

Nearby

Flash Flood Warnings in Iowa, 2017Every 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.