Alert archive / Minnesota / Flash Flood Warnings in 2020

Flash Flood Warning 12, NWS Twin Cities, MN

July 25, 20204 counties in Minnesota

NWS Twin Cities, MN issued this flash flood warning at Jul 25, 2020, 9:34 PM CDT for 4 counties in Minnesota. It was in force for 6 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 25, 2020, 9:34 PM CDT (02:34 UTC)
Expired: Jul 26, 2020, 3:15 AM CDT
In force: 6 hr
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Flood severity: None

Counties Blue Earth County, MN, Le Sueur County, MN, Nicollet County, MN, Rice County, MN

The radar

The Minneapolis radar (KMPX), 60 km from the middle of the area, began a volume at 02:33 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, 2.6 hours before the alert went out and 60 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1584 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 935 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 229 m²/s²
0-3 km storm-relative helicity: 363 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 12.8

Open this sounding in Storm Lab

The text

As transmitted.

378 
WGUS53 KMPX 260234
FFWMPX
MNC013-079-103-131-260815-
/O.NEW.KMPX.FF.W.0012.200726T0234Z-200726T0815Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Twin Cities/Chanhassen MN
934 PM CDT Sat Jul 25 2020

The National Weather Service in the Twin Cities has issued a

* Flash Flood Warning for...
  Northeastern Blue Earth County in south central Minnesota...
  Le Sueur County in south central Minnesota...
  Southeastern Nicollet County in south central Minnesota...
  Western Rice County in south central Minnesota...

* Until 315 AM CDT.

* At 934 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 2 inches of rain have 
  fallen. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  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 2 to 4 inches are possible.

* Some locations that will experience flash flooding include...
  Mankato, Faribault, North Mankato, St. Peter, New Prague, 
  Lonsdale, Montgomery, Le Center, Eagle Lake, Waterville, Webster, 
  Nicollet, Madison Lake, Morristown, Kasota, Elysian, Warsaw, 
  Cleveland, Oshawa and Skyline.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4422 9423 4438 9417 4439 9366 4454 9365
      4454 9328 4447 9328 4447 9325 4420 9326
      4420 9377 4411 9377 4411 9405

FLASH FLOOD...RADAR INDICATED

$$

CTG

1 follow-up statement

254 
WGUS73 KMPX 260808
FFSMPX

Flash Flood Statement
National Weather Service Twin Cities/Chanhassen MN
308 AM CDT Sun Jul 26 2020

MNC013-079-103-131-260818-
/O.EXP.KMPX.FF.W.0012.000000T0000Z-200726T0815Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Blue Earth MN-Le Sueur MN-Nicollet MN-Rice MN-
308 AM CDT Sun Jul 26 2020

...FLASH FLOOD WARNING WILL EXPIRE AT 315 AM CDT EARLY THIS MORNING 
FOR NORTHEASTERN BLUE EARTH, LE SUEUR, SOUTHEASTERN NICOLLET AND 
WESTERN RICE COUNTIES...

Flooding continues to remain a threat and a new warning will be 
issued. Please continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 800 AM CDT for portions 
of east central Minnesota...south central Minnesota and southeast 
Minnesota.

LAT...LON 4422 9423 4438 9417 4439 9366 4454 9365
      4454 9352 4454 9328 4452 9328 4450 9328
      4449 9328 4447 9328 4447 9325 4420 9326
      4420 9377 4411 9377 4411 9405

$$

TDH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 7:08 PM CDT	Special Weather Statement	MPX	Nicollet	52 min
Jul 25, 7:20 PM CDT	Tornado Warning	MPX	Nicollet, Sibley	25 min
Jul 25, 8:15 PM CDT	Special Weather Statement	MPX	Le Sueur, Nicollet, Sibley	2 hr
Jul 25, 8:20 PM CDT	Flash Flood Warning	MPX	Le Sueur, Nicollet, Scott, Sibley	6 hr
Jul 25, 8:54 PM CDT	Flash Flood Warning	MPX	Brown, Nicollet, Renville, Sibley	8 hr
Jul 25, 9:18 PM CDT	Flash Flood Watch	MPX	Blue Earth, Brown, Dakota, Goodhue, Le Sueur, Nicollet and 5 more	12 hr
Jul 26, 2:22 AM CDT	Special Weather Statement	MPX	Renville	38 min
Jul 26, 2:24 AM CDT	Flash Flood Warning	MPX	Le Sueur, Nicollet, Scott, Sibley	5 hr
Jul 26, 2:26 AM CDT	Special Weather Statement	MPX	Douglas, Pope, Stevens	34 min
Jul 26, 2:44 AM CDT	Special Weather Statement	MPX	Lac qui Parle, Swift	31 min
Jul 26, 3:01 AM CDT	Special Weather Statement	MPX	Douglas, Pope, Todd	44 min
Jul 26, 3:10 AM CDT	Flash Flood Warning	MPX	Blue Earth, Le Sueur, Nicollet, Rice, Waseca	5 hr
Jul 26, 3:18 AM CDT	Special Weather Statement	MPX	Chippewa, Lac qui Parle, Swift	27 min
Jul 26, 3:45 AM CDT	Special Weather Statement	MPX	Todd	30 min
Jul 26, 4:30 AM CDT	Special Weather Statement	MPX	Benton, Stearns	30 min
Jul 26, 4:57 AM CDT	Flash Flood Warning	MPX	Brown, Nicollet, Redwood, Renville, Sibley	3 hr
Jul 26, 8:04 AM CDT	Areal Flood Warning	MPX	Blue Earth, Brown, Le Sueur, Nicollet, Redwood, Renville and 2 more	9 hr

Nearby

Flash Flood Warnings in Minnesota, 2020 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.