Alert archive / Minnesota / Flash Flood Warnings in 2020

Flash Flood Warning 14, NWS Twin Cities, MN

July 26, 20205 counties in Minnesota

NWS Twin Cities, MN issued this flash flood warning at Jul 26, 2020, 3:10 AM CDT for 5 counties in Minnesota. It was in force for 5 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: Jul 26, 2020, 3:10 AM CDT (08:10 UTC)
Expired: Jul 26, 2020, 8:04 AM CDT
In force: 5 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, Waseca County, MN

The radar

The Minneapolis radar (KMPX), 76 km from the middle of the area, began a volume at 08:13 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
Jul 26, 5:49 AM CDT	FLASH FLOOD	1 Se North Mankato, MN	US 169 RAMPS TO CENTER ST & LOOKOUT DR ARE CLOSED DUE TO FLOODING.
Jul 26, 7:00 AM CDT	HEAVY RAIN 7.33	Waterville, MN	24 HOUR RAINFALL REPORT FROM STATION MN-LS-19.
Jul 26, 7:30 AM CDT	HEAVY RAIN 8.5	St. Peter, MN
Jul 26, 7:42 AM CDT	FLASH FLOOD	1 Sse Kasota, MN	FLOODING ON HIGHWAY 22 SOUTH OF KASOTA BETWEEN TWP 140 AND TWP 298.

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 00:00Z, 8.2 hours before the alert went out and 75 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.

380 
WGUS53 KMPX 260810
FFWMPX
MNC013-079-103-131-161-261315-
/O.NEW.KMPX.FF.W.0014.200726T0810Z-200726T1315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Twin Cities/Chanhassen MN
310 AM CDT Sun Jul 26 2020

The National Weather Service in the Twin Cities has issued a

* Flash Flood Warning for...
  Northern Blue Earth County in south central Minnesota...
  Le Sueur County in south central Minnesota...
  Southeastern Nicollet County in south central Minnesota...
  Southwestern Rice County in south central Minnesota...
  Northern Waseca County in south central Minnesota...

* Until 815 AM CDT.

* At 310 AM CDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  2 and 5 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar and automated gauges.

  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 3 inches are possible.

* Some locations that will experience flash flooding include...
  Mankato, Faribault, New Ulm, North Mankato, St. Peter, Montgomery, 
  Lake Crystal, Le Center, Eagle Lake, Janesville, Waterville, 
  Nicollet, Madison Lake, Morristown, St. Clair, Kasota, Elysian, 
  Courtland, Warsaw and Good Thunder.

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.

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.

&&

LAT...LON 4436 9450 4437 9442 4439 9366 4451 9365
      4436 9325 4420 9326 4420 9341 4415 9341
      4403 9385 4400 9424 4419 9437 4426 9437
      4427 9441 4429 9442 4429 9443 4430 9443
      4432 9445 4433 9445

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

TDH

1 follow-up statement

001 
WGUS73 KMPX 261304
FFSMPX

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

MNC013-079-103-131-161-261314-
/O.CAN.KMPX.FF.W.0014.000000T0000Z-200726T1315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Blue Earth MN-Le Sueur MN-Nicollet MN-Rice MN-Waseca MN-
804 AM CDT Sun Jul 26 2020

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHERN BLUE EARTH, LE 
SUEUR, SOUTHEASTERN NICOLLET, SOUTHWESTERN RICE AND NORTHERN WASECA 
COUNTIES...

The heaviest rain has ended. However, flooding will continue 
throughout the day and a Flood Warning has been issued. Please 
continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 1200 PM CDT for portions 
of east central Minnesota...south central Minnesota and southeast 
Minnesota.

LAT...LON 4436 9450 4437 9442 4439 9366 4451 9365
      4436 9325 4420 9326 4420 9341 4415 9341
      4403 9385 4400 9424 4419 9437 4426 9437
      4427 9441 4429 9442 4429 9443 4430 9443
      4432 9445 4433 9445

$$

Borghoff

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 25, 9:34 PM CDT	Flash Flood Warning	MPX	Blue Earth, Le Sueur, Nicollet, Rice	6 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, 3:18 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.