Alert archive / Minnesota / Flash Flood Warnings in 2018

Flash Flood Warning 21, NWS Sioux Falls, SD

July 12, 20184 counties in Minnesota

NWS Sioux Falls, SD issued this flash flood warning at Jul 12, 2018, 5:35 PM CDT for 4 counties in Minnesota. It was in force for 3 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
Jul 12, 2018, 5:35 PM CDT (22:35 UTC)
Expired
Jul 12, 2018, 8:30 PM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Lincoln County, MN, Lyon County, MN, Murray County, MN, Pipestone County, MN

The radar

The Sioux Falls radar (KFSD), 99 km from the middle of the area, began a volume at 22:39 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

Minneapolis, MN (KMPX), launched 12:00Z, 10.6 hours before the alert went out and 191 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 12:00Z on 2018-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 745 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 12:00Z on 2018-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 387 square meters per square second.193958Sfc1 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
745 J/kg
Mixed-layer CIN
-244 J/kg
Mixed-layer LCL
1291 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
387 m²/s²
0-3 km storm-relative helicity
437 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.3

Open this sounding in Storm Lab

The text

As transmitted.

927 
WGUS53 KFSD 122235
FFWFSD
MNC081-083-101-117-130130-
/O.NEW.KFSD.FF.W.0021.180712T2235Z-180713T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
535 PM CDT THU JUL 12 2018

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Southern Lyon County in southwestern Minnesota...
  Southeastern Lincoln County in southwestern Minnesota...
  Northeastern Pipestone County in southwestern Minnesota...
  Northwestern Murray County in southwestern Minnesota...

* Until 830 PM CDT.

* At 534 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

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

&&

LAT...LON 4414 9559 4405 9622 4431 9623 4443 9559

$$

Gillispie
2 follow-up statements
969 
WGUS73 KFSD 130009
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
709 PM CDT THU JUL 12 2018

MNC081-083-101-117-130130-
/O.CON.KFSD.FF.W.0021.000000T0000Z-180713T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lyon MN-Lincoln MN-Pipestone MN-Murray MN-
709 PM CDT THU JUL 12 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
SOUTHERN LYON...SOUTHEASTERN LINCOLN...NORTHEASTERN PIPESTONE AND
NORTHWESTERN MURRAY COUNTIES...

At 707 PM CDT, Doppler radar indicated that the heavy rain had moved 
out of the warned area. However, runoff from the earlier storms will 
continue for some time, and additional scattered showers and 
thunderstorms could redevelop through this evening. Up to three 
inches of rain have already fallen. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

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

&&

LAT...LON 4414 9559 4405 9622 4431 9623 4443 9559

$$

Gillispie
945 
WGUS73 KFSD 130130
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
830 PM CDT THU JUL 12 2018

MNC081-083-101-117-130140-
/O.EXP.KFSD.FF.W.0021.000000T0000Z-180713T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lyon MN-Lincoln MN-Pipestone MN-Murray MN-
830 PM CDT THU JUL 12 2018

...THE FLASH FLOOD WARNING FOR SOUTHERN LYON...SOUTHEASTERN
LINCOLN...NORTHEASTERN PIPESTONE AND NORTHWESTERN MURRAY COUNTIES HAS
EXPIRED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 4414 9559 4405 9622 4431 9623 4443 9559

$$

Hanko

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 12, 4:47 AM CDTFlash Flood WatchFSDCottonwood, Jackson, Lincoln, Lyon, Murray, Nobles and 2 more26 hr
Jul 12, 5:08 PM CDTSevere Thunderstorm WarningFSDPipestone, Rock52 min
Jul 12, 5:42 PM CDTSevere Thunderstorm WarningFSDMurray, Pipestone33 min

Nearby

Flash Flood Warnings in Minnesota, 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.