Alert archive / Minnesota / Flash Flood Warnings in 2020

Flash Flood Warning 3, NWS Sioux Falls, SD

June 18, 2020Nobles County, Minnesota

NWS Sioux Falls, SD issued this flash flood warning at Jun 18, 2020, 4:37 PM CDT for Nobles County, Minnesota. It was in force for 3 hr. 2 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 18, 2020, 4:37 PM CDT (21:37 UTC)
Expired
Jun 18, 2020, 7:30 PM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

County Nobles County, MN

The radar

The Sioux Falls radar (KFSD), 89 km from the middle of the area, began a volume at 21:39 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.

What was reported inside it

TimeReportWhereRemark
Jun 18, 4:42 PM CDTFLASH FLOODWorthington, MNWATER OVER MARINE AVE NEAR THE HIGH SCHOOL IN WORTHINGTON.
Jun 18, 4:48 PM CDTFLASH FLOODWorthington, MNCOUNTY SHERIFF HAD ONE REPORT OF A STALLED VEHICLE AND 6 REPORTS OF STREET FLOODING.

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, 9.6 hours before the alert went out and 209 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 2020-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 39 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 2020-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 319 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
39 J/kg
Mixed-layer CIN
-270 J/kg
Mixed-layer LCL
1316 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
319 m²/s²
0-3 km storm-relative helicity
276 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

531 
WGUS53 KFSD 182137
FFWFSD
MNC105-190030-
/O.NEW.KFSD.FF.W.0003.200618T2137Z-200619T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
437 PM CDT Thu Jun 18 2020

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Central Nobles County in southwestern Minnesota...

* Until 730 PM CDT.

* At 435 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have
  already fallen. Flash flooding is ongoing or expected to begin
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area through 600 PM CDT.

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 4356 9564 4353 9590 4378 9571 4378 9545
      4377 9545

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

Gillispie
2 follow-up statements
812 
WGUS73 KFSD 182328
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
628 PM CDT Thu Jun 18 2020

MNC105-190030-
/O.CON.KFSD.FF.W.0003.000000T0000Z-200619T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Nobles MN-
628 PM CDT Thu Jun 18 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM CDT FOR
CENTRAL NOBLES COUNTY...

At 620 PM CDT, emergency management reported that flash flooding is 
beginning to subside in the Worthington area. Three to three and a 
half inches of rainfall is continuing to cause issues for low spots 
in town, but crews are blocking off impacted roads. Little to no 
additional rain is expected.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Emergency management.

IMPACT...Flooding of small creeks and streams, urban areas, 
         highways, streets and underpasses as well as other drainage 
         and low lying areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4356 9564 4353 9590 4378 9571 4378 9545
      4377 9545

FLASH FLOOD...OBSERVED

$$

VandenBoogart
649 
WGUS73 KFSD 190023
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
723 PM CDT Thu Jun 18 2020

MNC105-190031-
/O.EXP.KFSD.FF.W.0003.000000T0000Z-200619T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Nobles MN-
723 PM CDT Thu Jun 18 2020

...THE FLASH FLOOD WARNING FOR CENTRAL NOBLES COUNTY WILL EXPIRE AT
730 PM CDT...

Rain has ended and flash flood waters have receded. Flooding is no 
longer expected to pose a major threat. Some ponding of water in low 
spots may continue through the evening. Please continue to heed any 
remaining road closures.

LAT...LON 4356 9564 4353 9590 4378 9571 4378 9545
      4377 9545

$$

VandenBoogart

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 18, 2:59 PM CDTSevere Thunderstorm WarningFSDJackson, Nobles46 min

Nearby

Flash Flood Warnings in Minnesota, 2020Every flash flood warning in 2020

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.