Alert archive / Minnesota / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Twin Cities, MN

August 27, 2021Freeborn County, Minnesota

NWS Twin Cities, MN issued this flash flood warning at Aug 27, 2021, 2:06 AM CDT for Freeborn County, Minnesota. 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
Aug 27, 2021, 2:06 AM CDT (07:06 UTC)
Expired
Aug 27, 2021, 7:00 AM CDT
In force
5 hr
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Flood severity
None

County Freeborn County, MN

The radar

The Minneapolis radar (KMPX), 147 km from the middle of the area, began a volume at 07:10 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 00:00Z, 7.1 hours before the alert went out and 148 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 00:00Z on 2021-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2021-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 393 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
792 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
393 m²/s²
0-3 km storm-relative helicity
392 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

704 
WGUS53 KMPX 270706
FFWMPX
MNC047-271200-
/O.NEW.KMPX.FF.W.0002.210827T0706Z-210827T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Twin Cities/Chanhassen MN
206 AM CDT Fri Aug 27 2021

The National Weather Service in the Twin Cities has issued a

* Flash Flood Warning for...
  Southeastern Freeborn County in south central Minnesota...

* Until 700 AM CDT.

* At 206 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 inches of rain 
  have fallen. The expected rainfall rate is 1 to 2 inches in 1 
  hour. Additional rainfall amounts of 2 to 3 inches are possible in 
  the warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Glenville, Emmons, London and Myrtle.

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 4350 9361 4361 9306 4360 9305 4350 9305

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

$$

Borghoff
1 follow-up statement
116 
WGUS73 KMPX 271202
FFSMPX

Flash Flood Statement
National Weather Service Twin Cities/Chanhassen MN
702 AM CDT Fri Aug 27 2021

MNC047-271212-
/O.EXP.KMPX.FF.W.0002.000000T0000Z-210827T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Freeborn MN-
702 AM CDT Fri Aug 27 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHEASTERN FREEBORN 
COUNTY...

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

LAT...LON 4350 9361 4361 9306 4360 9305 4350 9305

$$

@NWSTwinCities

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 27, 12:56 AM CDTSpecial Weather StatementMPXMartin34 min
Aug 27, 2:59 AM CDTSpecial Weather StatementMPXBrown, Faribault, Martin, Redwood, Watonwan3 hr
Aug 27, 4:09 AM CDTFlash Flood WarningMPXFaribault, Freeborn3 hr
Aug 27, 6:12 AM CDTSpecial Weather StatementMPXRamsey2 hr

Nearby

Flash Flood Warnings in Minnesota, 2021Every flash flood warning 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.