Alert archive / Iowa / Flash Flood Warnings in 2018

Flash Flood Warning 21, NWS Des Moines, IA

June 30, 2018Dallas County, Polk County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 30, 2018, 8:16 PM CDT for Dallas County, Polk County, Iowa. It was in force for 6 hr. 15 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 30, 2018, 8:16 PM CDT (01:16 UTC)
Expired
Jul 1, 2018, 2:15 AM CDT
In force
6 hr
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Emergency
Flash flood emergency
Flood severity
None

Counties Dallas County, IA, Polk County, IA

The radar

The Des Moines radar (KDMX), 13 km from the middle of the area, began a volume at 01:18 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 30, 8:48 PM CDTHEAVY RAIN 2.682 Ene Urbandale, IA2.68 INCHES OF RAIN MEASURED 8:47 PM. MULTIPLE CARS STALLED ON MEREDITH AVE. 8 OF WATER RUSHING DOWN 67TH STREET TO MEREDITH.
Jun 30, 8:49 PM CDTFLASH FLOOD2 Ene Urbandale, IA2.68 INCHES OF RAIN MEASURED 8:47 PM. MULTIPLE CARS STALLED ON MEREDITH AVE. 8 OF WATER RUSHING DOWN 67TH STREET TO MEREDITH.
Jun 30, 8:56 PM CDTFLASH FLOOD1 E Clive, IATRAINED SPOTTER IN CLIVE REPORTS WATER RUNNING OVER THE CURBS ON RESIDENTIAL STREETS SOUTH OF HICKMAN DRIVE.
Jun 30, 9:13 PM CDTHEAVY RAIN 5.61 Se Johnston, IA5.6 INCHES VIA SOCIAL MEDIA.
Jun 30, 9:22 PM CDTFLASH FLOOD2 Sse Windsor Heights, IA63RD AND GRAND NEAR WEST DES MOINES REPORTED UNDERWATER VIA SOCIAL MEDIA.
Jun 30, 9:39 PM CDTFLASH FLOODSaylorville, IAMULTIPLE WATER RESCUES ACROSS ANKENY, JOHNSTON, DES MOINES AND URBANDALE. VEHICLES STALLED OUT IN STREET FLOODING WITH WATER HALF WAY UP THE DOORS OF THE CARS.
Jun 30, 9:42 PM CDTFLASH FLOOD2 Se Grimes, IAWATER COVERING THE ROAD IN THE AREA.
Jun 30, 9:44 PM CDTHEAVY RAIN 7.31 Nnw Windsor Heights, IAREPORT VIA SOCIAL MEDIA. 7.3 INCHES REPORTED FROM URBANDALE.
Jun 30, 10:22 PM CDTHEAVY RAIN 7.322 Ene Urbandale, IA7.32 INCHES AT 67TH AND MEREDITH IN URBANDALE AS OF 1022 PM.
Jun 30, 10:28 PM CDTHEAVY RAIN 5.51 S Saylorville, IA5.5 INCHES SINCE 7:30 PM.
Jun 30, 10:41 PM CDTHEAVY RAIN 6.51 Ese Altoona, IA6.5 INCHES IN ALTOONA SINCE 8 PM.
Jun 30, 10:44 PM CDTHEAVY RAIN 7.1Johnston, IA7.1 INCHES OF RAIN IN JOHNSTON, IA AS OF 1043 PM CDT.
Jun 30, 10:49 PM CDTFLASH FLOOD3 Ene Windsor Heights, IAREPORT VIA SOCIAL MEDIA. STREET AND GUARD RAILS BEING WASHED AWAY WITH THE GROUND DETERIORATING.
Jun 30, 11:16 PM CDTHEAVY RAIN 7.51 S Saylorville, IA
Jun 30, 11:24 PM CDTHEAVY RAIN 7.51 Sse Saylorville, IA7.50 INCHES NEAR SAYLORVILLE AREA IN RURAL POLK COUNTY AS OF 1124 PM CDT.

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

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.3 hours before the alert went out and 220 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, Omaha, NE at 00:00Z on 2018-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2827 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, Omaha, NE at 00:00Z on 2018-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 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
2827 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
801 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
194 m²/s²
Significant tornado parameter
2.5
Supercell composite
15.5

Open this sounding in Storm Lab

The text

As transmitted.

870 
WGUS53 KDMX 010116
FFWDMX
IAC049-153-010715-
/O.NEW.KDMX.FF.W.0021.180701T0116Z-180701T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
816 PM CDT SAT JUN 30 2018

The National Weather Service in Des Moines  has issued a

* Flash Flood Warning for...
  Polk County in central Iowa...
  Dallas County in central Iowa...

* Until 215 AM CDT Sunday.

* At 813 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. One to three inches of rain has 
  already fallen across northern Polk County and eastern Dallas 
  Counties with additional thunderstorms developing. Flash flooding 
  is already occuring with expansion likely overnight.

* Some locations that will experience flooding include...
  Des Moines, West Des Moines, Ankeny, Urbandale, Johnston, Clive,
  Altoona, Waukee, Norwalk, Pleasant Hill, Grimes, Perry, Adel,
  Windsor Heights, Carlisle, Bondurant, Saylorville, Mitchellville,
  Dallas Center and Earlham.

Additional rainfall amounts of one to three inches are possible in
the warned area this evening and overnight.  

This includes the following highways...
 Interstate 35 between mile markers 67 and 72, and between mile
markers 87 and 93.
 Interstate 80 between mile markers 100 and 149.
 Interstate 235 between mile markers 1 and 14.

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.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4149 9342 4151 9342 4151 9356 4150 9424
      4160 9424 4160 9428 4186 9428 4186 9381
      4174 9380 4174 9335 4149 9333

$$

MF
4 follow-up statements
544 
WGUS73 KDMX 010151
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
851 PM CDT SAT JUN 30 2018

IAC049-153-010715-
/O.CON.KDMX.FF.W.0021.000000T0000Z-180701T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Polk IA-Dallas IA-
851 PM CDT SAT JUN 30 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 215 AM CDT FOR
POLK AND DALLAS COUNTIES...

At 848 PM CDT, emergency management and trained spotters reported 
heavy rain due to thunderstorms over the Des Moines metro area.  Up 
to four inches of rain have already fallen. Flash flooding is 
occurring and the severity is expected to increase!

Some locations that will experience flooding include...
Des Moines, West Des Moines, Ankeny, Urbandale, Johnston, Clive,
Altoona, Waukee, Norwalk, Pleasant Hill, Grimes, Perry, Adel, Windsor
Heights, Carlisle, Bondurant, Saylorville, Mitchellville, Dallas
Center and Earlham.

Additional rainfall amounts of one to three inches are possible in
the warned area this evening and overnight.

This includes the following highways...
 Interstate 35 between mile markers 67 and 72, and between mile
markers 87 and 93.
 Interstate 80 between mile markers 100 and 149.
 Interstate 235 between mile markers 1 and 14.

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.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4149 9342 4151 9342 4151 9356 4150 9424
      4160 9424 4160 9428 4186 9428 4186 9381
      4174 9380 4174 9335 4149 9333

$$

MF
311 
WGUS73 KDMX 010202 CCA
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
902 PM CDT SAT JUN 30 2018

IAC049-153-010715-
/O.COR.KDMX.FF.W.0021.000000T0000Z-180701T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Polk IA-Dallas IA-
902 PM CDT SAT JUN 30 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 215 AM CDT FOR
POLK AND DALLAS COUNTIES...

At 859 PM CDT, trained weather spotters reported flash flooding in 
across Polk and Dallas Counties.  Numerous roads have water over 
them and creeks and streams are flowing out of their banks.  Up to 
four inches of rain have already fallen. Flash flooding is already 
occurring and the SEVERITY IS LIKELY TO INCREASE!

Some locations that will experience flooding include...
Des Moines, West Des Moines, Ankeny, Urbandale, Johnston, Clive,
Altoona, Waukee, Norwalk, Pleasant Hill, Grimes, Perry, Adel, Windsor
Heights, Carlisle, Bondurant, Saylorville, Mitchellville, Dallas
Center and Earlham.

Additional rainfall amounts of one to three inches are possible in 
the warned area.

Flood waters are moving down Four Mile Creek from in and around 
Ankeny to Easton Boulevard.  The flood crest is expected to reach 
15.3 feet around 4 am Sunday.  

This includes the following highways... Interstate 35 between mile 
markers 67 and 72, and between mile markers 87 and 93.
 Interstate 80 between mile markers 100 and 149.
 Interstate 235 between mile markers 1 and 14.

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.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4149 9342 4151 9342 4151 9356 4150 9424
      4160 9424 4160 9428 4186 9428 4186 9381
      4174 9380 4174 9335 4149 9333

$$

MF
649 
WGUS73 KDMX 010234
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
934 PM CDT SAT JUN 30 2018

IAC049-153-010715-
/O.CON.KDMX.FF.W.0021.000000T0000Z-180701T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Polk IA-Dallas IA-
934 PM CDT SAT JUN 30 2018

...THIS IS A FLASH FLOOD EMERGENCY FOR DES MOINES METRO AREA...

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 215 AM CDT FOR
POLK AND DALLAS COUNTIES...

At 931 PM CDT, trained weather spotters reported widespread and 
severe flash flooding across portions of Polk and Dallas Counties. 
Rainfall reports in excess of 5 inches have already occurred with 
additional heavy rainfall ongoing.  

This is a FLASH FLOOD EMERGENCY for the DES MOINES METRO AREA. This 
is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!

Some locations that will experience flooding include...
Des Moines, West Des Moines, Ankeny, Urbandale, Johnston, Clive,
Altoona, Waukee, Norwalk, Pleasant Hill, Grimes, Perry, Adel, Windsor
Heights, Carlisle, Bondurant, Saylorville, Mitchellville, Dallas
Center and Earlham.

Additional rainfall amounts of two to four inches are possible in 
the warned area through tonight.

This includes the following highways...
 Interstate 35 between mile markers 67 and 72, and between mile
markers 87 and 93.
 Interstate 80 between mile markers 100 and 149.
 Interstate 235 between mile markers 1 and 14.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. This is an extremely dangerous and
life-threatening situation. Do not attempt to travel unless you are
fleeing an area subject to flooding or under an evacuation order.

Please report flooding to your local law enforcement agency when you 
can do so safely.

&&

LAT...LON 4149 9342 4151 9342 4151 9356 4150 9424
      4160 9424 4160 9428 4186 9428 4186 9381
      4174 9380 4174 9335 4149 9333

$$

MF
854 
WGUS73 KDMX 010626
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
126 AM CDT SUN JUL 1 2018

IAC049-153-010715-
/O.CON.KDMX.FF.W.0021.000000T0000Z-180701T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Polk IA-Dallas IA-
126 AM CDT SUN JUL 1 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 215 AM CDT FOR
POLK AND DALLAS COUNTIES...

At 124 AM CDT, local law enforcement reported heavy rain and flash 
flooding across the warned area. 3 to 8 inches of rain have already 
fallen. Significant flash flooding is occurring with reports of 
stranded vehicles, roads blocked by water, and creeks and streams 
out of banks.  

Some locations that will experience flooding include...
Des Moines, West Des Moines, Ankeny, Urbandale, Johnston, Clive,
Altoona, Waukee, Norwalk, Pleasant Hill, Grimes, Perry, Adel, Windsor
Heights, Carlisle, Bondurant, Saylorville, Mitchellville, Dallas
Center and Earlham.

Additional rainfall amounts of one to two inches are possible in the 
warned area the remainder of tonight.

This includes the following highways...
 Interstate 35 between mile markers 67 and 72, and between mile
markers 87 and 93.
 Interstate 80 between mile markers 100 and 149.
 Interstate 235 between mile markers 1 and 14.

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 4149 9342 4151 9342 4151 9356 4150 9424
      4160 9424 4160 9428 4186 9428 4186 9381
      4174 9380 4174 9335 4149 9333

$$

MF

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 7:03 PM CDTSevere Thunderstorm WarningDMXBlack Hawk, Grundy, Marshall, Tama57 min
Jun 30, 7:05 PM CDTSevere Thunderstorm WarningDMXPolk, Story40 min
Jun 30, 7:24 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Polk, Story36 min
Jun 30, 7:33 PM CDTFlash Flood WarningDMXPolk, Story6 hr
Jun 30, 7:42 PM CDTFlash Flood WarningDMXBlack Hawk, Grundy6 hr
Jun 30, 7:54 PM CDTSevere Thunderstorm WarningDMXAdair, Audubon, Cass, Guthrie35 min
Jun 30, 8:02 PM CDTFlash Flood Warning EmergencyDMXPolk6 hr
Jun 30, 8:14 PM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison46 min
Jun 30, 8:45 PM CDTSevere Thunderstorm WarningDMXAdair, Guthrie, Madison30 min
Jun 30, 8:50 PM CDTRiver Flood WarningDMXPolk36 hr
Jun 30, 9:04 PM CDTSevere Thunderstorm WarningDMXPolk, Warren41 min
Jun 30, 9:08 PM CDTSevere Thunderstorm WarningDMXAdair, Boone, Dallas, Greene, Guthrie, Madison28 min
Jun 30, 9:11 PM CDTSevere Thunderstorm WarningDMXClarke, Madison, Marion, Polk, Warren34 min
Jun 30, 9:12 PM CDTRiver Flood WarningDMXPolk15 hr
Jun 30, 9:23 PM CDTRiver Flood WarningDMXDallas, Polk16 hr
Jun 30, 9:37 PM CDTRiver Flood WarningDMXBlack Hawk7 days
Jun 30, 9:37 PM CDTRiver Flood WarningDMXPolk9 days
Jun 30, 9:58 PM CDTSevere Thunderstorm WarningDMXJasper, Mahaska, Marion, Polk, Warren47 min
Jun 30, 10:12 PM CDTFlash Flood WarningDMXJasper6 hr
Jun 30, 10:47 PM CDTRiver Flood WatchDMXBoone, Hamilton, Webster4 hr
Jun 30, 10:47 PM CDTRiver Flood WatchDMXBlack Hawk3 days
Jun 30, 10:47 PM CDTRiver Flood WatchDMXPolk, Story7 hr
Jun 30, 10:47 PM CDTRiver Flood WatchDMXJasper, Marion, Polk7 hr
Jun 30, 10:47 PM CDTRiver Flood WatchDMXStory10 hr
Jun 30, 11:04 PM CDTRiver Flood WarningDMXPolk32 hr
Jun 30, 11:05 PM CDTRiver Flood WarningDMXPolk38 hr
Jun 30, 11:05 PM CDTRiver Flood WarningDMXPolk11 hr
Jul 1, 1:21 AM CDTFlash Flood WarningDMXDallas, Jasper, Polk, Story8 hr
Jul 1, 1:36 AM CDTAreal Flood WarningDMXBlack Hawk, Bremer, Butler, Grundy, Hardin9 hr
Jul 1, 2:34 AM CDTRiver Flood WarningDMXBoone, Hamilton, Webster41 hr
Jul 1, 4:30 AM CDTRiver Flood WarningDMXWright4 days
Jul 1, 4:30 AM CDTRiver Flood WarningDMXBlack Hawk70 hr
Jul 1, 4:30 AM CDTRiver Flood WarningDMXPolk47 hr
Jul 1, 4:30 AM CDTRiver Flood WarningDMXDallas, Greene5 days
Jul 1, 5:51 AM CDTRiver Flood WarningDMXJasper, Marion, Polk40 hr
Jul 1, 9:08 AM CDTAreal Flood WarningDMXDallas, Jasper, Polk, Story12 hr

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.