Alert archive / Iowa / Flash Flood Warnings in 2018
Flash Flood Warning 29, NWS Des Moines, IA
NWS Des Moines, IA issued this flash flood warning at Sep 1, 2018, 9:59 PM CDT for Mahaska County, Monroe County, Wapello County, Iowa. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Sep 1, 2018, 9:59 PM CDT (02:59 UTC)
- Expired
- Sep 2, 2018, 3:05 AM CDT
- In force
- 5 hr
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Flood severity
- None
Counties Mahaska County, IA, Monroe County, IA, Wapello County, IA
The radar
The Des Moines radar (KDMX), 122 km from the middle of the area, began a volume at 03:03 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
Davenport, (KDVN), launched 00:00Z, 3.0 hours before the alert went out and 172 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.
- Mixed-layer CAPE
- 1803 J/kg
- Mixed-layer CIN
- -67 J/kg
- Mixed-layer LCL
- 1189 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 109 m²/s²
- 0-3 km storm-relative helicity
- 160 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 6.9
The text
As transmitted.
153
WGUS53 KDMX 020259
FFWDMX
IAC123-135-179-020900-
/O.NEW.KDMX.FF.W.0029.180902T0259Z-180902T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Des Moines IA
959 PM CDT SAT SEP 1 2018
The National Weather Service in Des Moines has issued a
* Flash Flood Warning for...
Northeastern Monroe County in south central Iowa...
Northern Wapello County in southeastern Iowa...
Southeastern Mahaska County in south central Iowa...
* Until 400 AM CDT Sunday.
* At 957 PM CDT, local law enforcement reported thunderstorms
producing heavy rain across the warned area. Up to two inches of
rain have already fallen. Flash flooding is expected to begin
shortly. The Poweshiek County Sheriff reported a gravel road
washed out along 120th St between 310th and 320th at 947 pm.
* Some locations that will experience flooding include...
Oskaloosa, Eddyville, Hedrick, Ottumwa Industrial Airport, Fremont,
University Park, Rose Hill, Kirkville, Chillicothe, Keomah Village,
Lake Keomah State Park and Oskaloosa Municipal Airport.
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 4106 9264 4118 9282 4140 9241 4117 9241
4116 9218 4115 9220
$$
Small2 follow-up statements
352
WGUS73 KDMX 020431
FFSDMX
Flash Flood Statement
National Weather Service Des Moines IA
1131 PM CDT SAT SEP 1 2018
IAC123-135-179-020900-
/O.CON.KDMX.FF.W.0029.000000T0000Z-180902T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe IA-Wapello IA-Mahaska IA-
1131 PM CDT SAT SEP 1 2018
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 400 AM CDT FOR
NORTHEASTERN MONROE...NORTHERN WAPELLO AND SOUTHEASTERN MAHASKA
COUNTIES...
At 1129 PM CDT, Doppler radar indicated thunderstorms produced heavy
rain across the warned area early this evening. Up to three inches
of rain has already fallen with local amounts of four or more
possible. This is in addition to heavy rains that fell earlier
Saturday morning. Flash flooding is occurring or expected to begin
shortly.
Some locations that will experience flooding include...
Oskaloosa, Eddyville, Hedrick, Ottumwa Industrial Airport, Fremont,
University Park, Rose Hill, Kirkville, Chillicothe, Keomah Village,
Lake Keomah State Park and Oskaloosa Municipal Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 4106 9264 4118 9282 4140 9241 4117 9241
4116 9218 4115 9220
$$
Small866
WGUS73 KDMX 020805
FFSDMX
Flash Flood Statement
National Weather Service Des Moines IA
305 AM CDT SUN SEP 2 2018
IAC123-135-179-020811-
/O.CAN.KDMX.FF.W.0029.000000T0000Z-180902T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe IA-Wapello IA-Mahaska IA-
305 AM CDT SUN SEP 2 2018
...THE FLASH FLOOD WARNING FOR NORTHEASTERN MONROE...NORTHERN WAPELLO
AND SOUTHEASTERN MAHASKA COUNTIES IS CANCELLED...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Calls to local law enforcement indicate that few impacts
remain across the region. If road barricades or barriers are
encountered, please continue to heed any road closures
LAT...LON 4106 9264 4118 9282 4140 9241 4117 9241
4116 9218 4115 9220
$$
REVThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 1, 7:02 PM CDT | Special Weather Statement | DMX | Boone, Story | 58 min |
| Sep 1, 7:07 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Dallas, Polk, Story | 38 min |
| Sep 1, 7:14 PM CDT | Severe Thunderstorm Warning | DMX | Jasper, Polk, Story | 46 min |
| Sep 1, 7:36 PM CDT | Severe Thunderstorm Warning | DMX | Jasper, Polk | 54 min |
| Sep 1, 7:51 PM CDT | Severe Thunderstorm Warning | DMX | Dallas, Polk, Story | 39 min |
| Sep 1, 8:16 PM CDT | Severe Thunderstorm Warning | DMX | Mahaska | 14 min |
| Sep 1, 8:50 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Dallas, Polk, Story | 40 min |
| Sep 1, 9:20 PM CDT | Flash Flood Warning | DMX | Boone, Dallas, Polk, Story | 6 hr |
| Sep 1, 9:40 PM CDT | River Flood Warning | DMX | Black Hawk | 10 days |
| Sep 1, 10:04 PM CDT | Special Weather Statement | DMX | Adair, Adams, Cass | 56 min |
| Sep 1, 10:16 PM CDT | Flash Flood Warning | DMX | Poweshiek | 6 hr |
| Sep 1, 10:47 PM CDT | Flash Flood Warning | DMX | Jasper, Poweshiek | 5 hr |
| Sep 2, 12:40 AM CDT | River Flood Warning | DMX | Jasper, Marion, Polk | 6 hr |
| Sep 2, 1:37 AM CDT | Flash Flood Warning | DMX | Marshall, Story | 2 hr |
| Sep 2, 3:47 AM CDT | Areal Flood Warning | DMX | Jasper, Marshall, Poweshiek, Story | 9 hr |
| Sep 2, 9:45 AM CDT | Flash Flood Watch | DMX | Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 30 more | 36 hr |
| Sep 2, 1:34 PM CDT | Flash Flood Warning | DMX | Black Hawk, Bremer, Butler | 6 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.