Alert archive / Iowa / Flash Flood Warnings in 2018
Flash Flood Warning 7, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this flash flood warning at Jun 24, 2018, 5:36 PM CDT for 4 counties in Iowa. It was in force for 3 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
- Jun 24, 2018, 5:36 PM CDT (22:36 UTC)
- Expired
- Jun 24, 2018, 8:30 PM CDT
- In force
- 3 hr
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Emergency
- Flash flood emergency
- Flood severity
- None
Counties Clay County, IA, Dickinson County, IA, O'Brien County, IA, Osceola County, IA
The radar
The Sioux Falls radar (KFSD), 121 km from the middle of the area, began a volume at 22:40 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 |
|---|---|---|---|
| Jun 24, 6:04 PM CDT | FLASH FLOOD | 1 Nne Arnolds Park, IA | HIGHWAY 71 TOTALLY FLOODED. AT LEAST ONE CAR REPORTED SUBMERGED. |
| Jun 24, 6:09 PM CDT | FLASH FLOOD | 1 Ssw Wahpeton, IA | EXTENSIVE FLOODING ALONG HIGHWAY 86 WITH VEHICLES STALLED. |
| Jun 24, 6:57 PM CDT | FLASH FLOOD | 7 Wsw West Okoboji, IA | WATER ACROSS ROAD WITH ESTIMATED 5 INCHES OF RAINFALL. |
| Jun 24, 7:00 PM CDT | HEAVY RAIN 5.5 | 2 Wsw Wahpeton, IA |
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 12:00Z, 10.6 hours before the alert went out and 224 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
- 216 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 1065 m above ground
- 0-6 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- -26 m²/s²
- 0-3 km storm-relative helicity
- 61 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
831 WGUS53 KFSD 242236 FFWFSD IAC041-059-141-143-250130- /O.NEW.KFSD.FF.W.0007.180624T2236Z-180625T0130Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED Flash Flood Warning National Weather Service Sioux Falls SD 536 PM CDT SUN JUN 24 2018 The National Weather Service in Sioux Falls has issued a * Flash Flood Warning for... Southeastern Osceola County in northwestern Iowa... Southern Dickinson County in northwestern Iowa... Northwestern Clay County in northwestern Iowa... Northeastern O'Brien County in northwestern Iowa... * Until 830 PM CDT. * At 536 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... Milford, Hartley, Arnolds Park, Primghar, Okoboji, Everly, Wahpeton, West Okoboji, Fostoria and Moneta. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. In hilly terrain there are hundreds of low water crossings which are potentially dangerous in heavy rain. Do not attempt to cross flooded roads. Find an alternate route. A Flash Flood Warning means that flooding is imminent or occurring. If you are in the warned area move to higher ground immediately. Residents living along streams and creeks should take immediate precautions to protect life and property. && LAT...LON 4338 9496 4304 9543 4308 9568 4338 9546 $$ Weisser
1 follow-up statement
905 WGUS73 KFSD 242314 FFSFSD Flash Flood Statement National Weather Service Sioux Falls SD 614 PM CDT SUN JUN 24 2018 IAC041-059-141-143-250130- /O.CON.KFSD.FF.W.0007.000000T0000Z-180625T0130Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Osceola IA-Dickinson IA-Clay IA-O'Brien IA- 614 PM CDT SUN JUN 24 2018 ...THIS IS A FLASH FLOOD EMERGENCY FOR Dickinson County... ...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR SOUTHEASTERN OSCEOLA...SOUTHERN DICKINSON...NORTHWESTERN CLAY AND NORTHEASTERN O'BRIEN COUNTIES... At 613 PM CDT, Doppler radar indicated heavy rain across the warned area. Up to three inches of rain have already fallen with another 2- 3 inches possible. Flash flooding is already occurring. This is a FLASH FLOOD EMERGENCY for very heavy rain. This is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW! Some locations that will experience flooding include... Milford, Hartley, Arnolds Park, Primghar, Okoboji, Everly, Wahpeton, West Okoboji, Fostoria and Moneta. PRECAUTIONARY/PREPAREDNESS ACTIONS... Move to higher ground now. This is an extremely dangerous and life-threatening situation. Do not attempt to travel unless you are fleeing an area subject to flooding or under an evacuation order. Excessive runoff from heavy rainfall will cause flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other drainage areas and low lying spots. In hilly terrain there are hundreds of low water crossings which are potentially dangerous in heavy rain. Do not attempt to cross flooded roads. Find an alternate route. A Flash Flood Warning means that flooding is imminent or occurring. If you are in the warned area move to higher ground immediately. Residents living along streams and creeks should take immediate precautions to protect life and property. && LAT...LON 4338 9496 4304 9543 4308 9568 4338 9546 $$ Weisser
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 24, 4:03 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 27 min |
| Jun 24, 4:46 PM CDT | Flash Flood Warning | FSD | Cherokee, O'Brien, Plymouth, Sioux | 4 hr |
| Jun 24, 4:52 PM CDT | Flash Flood Warning | FSD | Dickinson, Osceola | 4 hr |
| Jun 24, 5:01 PM CDT | Severe Thunderstorm Warning | FSD | Dickinson | 44 min |
| Jun 24, 5:26 PM CDT | Severe Thunderstorm Warning | FSD | Clay, Dickinson | 49 min |
| Jun 24, 5:29 PM CDT | Severe Thunderstorm Warning | FSD | Clay, Dickinson | 46 min |
| Jun 24, 6:18 PM CDT | Severe Thunderstorm Warning | FSD | Buena Vista, Clay | 42 min |
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.