Alert archive / Iowa / Flash Flood Watches in 2021

Flash Flood Watch 4, NWS Des Moines, IA

July 30, 202114 counties in Iowa

NWS Des Moines, IA issued this flash flood watch at Jul 30, 2021, 3:19 PM CDT for 14 counties in Iowa. It took effect at Jul 31, 2021, 1:00 AM CDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
Jul 30, 2021, 3:19 PM CDT (20:19 UTC)
In effect from
Jul 31, 2021, 1:00 AM CDT
Expired
Jul 31, 2021, 6:06 AM CDT
In force
5 hr
Issued by
NWS Des Moines, IA
Flood severity
None

Counties Adair County, IA, Adams County, IA, Audubon County, IA, Cass County, IA, Clarke County, IA, Decatur County, IA, Guthrie County, IA, Lucas County, IA, Madison County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Wayne County, IA

The radar

The Des Moines radar (KDMX), 77 km from the middle of the area, began a volume at 20:20 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.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.3 hours before the alert went out and 185 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 12:00Z on 2021-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 75 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 12:00Z on 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 225 square meters per square second.1939Sfc1 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
75 J/kg
Mixed-layer CIN
-269 J/kg
Mixed-layer LCL
904 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
225 m²/s²
0-3 km storm-relative helicity
322 m²/s²
Significant tornado parameter
0.0
Supercell composite
12.6

Open this sounding in Storm Lab

The text

As transmitted.

970 
WGUS63 KDMX 302019
FFADMX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Des Moines IA
319 PM CDT Fri Jul 30 2021

IAZ057-058-070>073-081>084-092>095-310430-
/O.NEW.KDMX.FF.A.0004.210731T0600Z-210731T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Audubon-Guthrie-Cass-Adair-Madison-Warren-Adams-Union-Clarke-Lucas-
Taylor-Ringgold-Decatur-Wayne-
Including the cities of Norwalk, Lenox, Audubon, Earlham, 
Fontanelle, Bayard, Mount Ayr, Allerton, Lamoni, Exira, Seymour, 
Panora, New Market, Casey, Atlantic, Corning, Bedford, Creston, 
Adair, Osceola, Stuart, Winterset, Greenfield, Guthrie Center, 
Chariton, Humeston, Leon, Corydon, Indianola, and Carlisle
319 PM CDT Fri Jul 30 2021

...FLASH FLOOD WATCH IN EFFECT FROM 1 AM CDT SATURDAY THROUGH 
SATURDAY MORNING...

The National Weather Service in Des Moines has issued a

* Flash Flood Watch for portions of south central Iowa, southwest 
  Iowa and west central Iowa, including the following areas, in 
  south central Iowa, Clarke, Decatur, Lucas, Madison, Ringgold, 
  Union, Warren and Wayne. In southwest Iowa, Adair, Adams, Cass and 
  Taylor. In west central Iowa, Audubon and Guthrie.

* From 1 AM CDT Saturday through Saturday morning.

* Heavy rainfall of 2 to 4 inches will be possible in the watch 
  area. Local amounts to 5  inches will be possible. This could lead 
  to localized flash flooding; especially in urban areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

REV
3 follow-up statements
300 
WGUS63 KDMX 310201
FFADMX

Flood Watch
National Weather Service Des Moines IA
901 PM CDT Fri Jul 30 2021

IAZ057-058-070>073-081>084-092>095-311015-
/O.CON.KDMX.FF.A.0004.210731T0600Z-210731T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Audubon-Guthrie-Cass-Adair-Madison-Warren-Adams-Union-Clarke-Lucas-
Taylor-Ringgold-Decatur-Wayne-
Including the cities of Norwalk, Lenox, Audubon, Earlham, 
Fontanelle, Bayard, Mount Ayr, Allerton, Lamoni, Exira, Seymour, 
Panora, New Market, Casey, Atlantic, Corning, Bedford, Creston, 
Adair, Osceola, Stuart, Winterset, Greenfield, Guthrie Center, 
Chariton, Humeston, Leon, Corydon, Indianola, and Carlisle
901 PM CDT Fri Jul 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 1 AM CDT SATURDAY 
THROUGH SATURDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Iowa, southwest Iowa and west central 
  Iowa, including the following areas, in south central Iowa, 
  Clarke, Decatur, Lucas, Madison, Ringgold, Union, Warren and 
  Wayne. In southwest Iowa, Adair, Adams, Cass and Taylor. In west 
  central Iowa, Audubon and Guthrie.

* From 1 AM CDT Saturday through Saturday morning.

* Heavy rainfall of 2 to 4 inches will be possible in the watch 
  area. Local amounts to 5 inches will be possible. This could lead 
  to localized flash flooding, especially in urban areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

KCM/Ansorge
153 
WGUS63 KDMX 310827
FFADMX

Flood Watch
National Weather Service Des Moines IA
327 AM CDT Sat Jul 31 2021


IAZ057-058-073-084-310930-
/O.CAN.KDMX.FF.A.0004.000000T0000Z-210731T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Audubon-Guthrie-Warren-Lucas-
Including the cities of Audubon, Exira, Guthrie Center, Panora, 
Bayard, Casey, Indianola, Norwalk, Carlisle, and Chariton
327 AM CDT Sat Jul 31 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for Audubon, Guthrie, Warren, and Lucas
counties has been cancelled.


$$

IAZ070>072-081>083-092>095-311500-
/O.CON.KDMX.FF.A.0004.000000T0000Z-210731T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cass-Adair-Madison-Adams-Union-Clarke-Taylor-Ringgold-Decatur-
Wayne-
Including the cities of Atlantic, Greenfield, Stuart, Adair, 
Fontanelle, Winterset, Earlham, Corning, Creston, Osceola, 
Bedford, Lenox, New Market, Mount Ayr, Lamoni, Leon, Corydon, 
Seymour, Allerton, and Humeston
327 AM CDT Sat Jul 31 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 AM CDT THIS
MORNING...

The Flash Flood Watch continues for

* Portions of south central Iowa and southwest Iowa

* Until 10 AM CDT this morning

* Heavy rainfall of 2 to 4 inches will be possible in the watch 
  area. Local amounts to 5 inches will be possible. This could 
  lead to localized flash flooding, especially in urban areas. 


PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$
076 
WGUS63 KDMX 311106
FFADMX

Flood Watch
National Weather Service Des Moines IA
606 AM CDT Sat Jul 31 2021

IAZ070>072-081>083-092>095-311215-
/O.CAN.KDMX.FF.A.0004.000000T0000Z-210731T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cass-Adair-Madison-Adams-Union-Clarke-Taylor-Ringgold-Decatur-Wayne-
Including the cities of Bedford, Leon, Lenox, Greenfield, Seymour, 
Adair, Humeston, Allerton, New Market, Earlham, Fontanelle, Osceola, 
Lamoni, Atlantic, Corning, Stuart, Mount Ayr, Corydon, Winterset, 
and Creston
606 AM CDT Sat Jul 31 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of south central Iowa and 
southwest Iowa, including the following areas, in south central 
Iowa, Clarke, Decatur, Madison, Ringgold, Union and Wayne. In 
southwest Iowa, Adair, Adams, Cass and Taylor has been cancelled.

The Flood Watch is cancelled. Flooding is no longer expected to pose 
a threat.

$$

Cogil

Nearby

Flash Flood Watches in Iowa, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.