Alert archive / Minnesota / Flash Flood Warnings in 2020

Flash Flood Warning 16, NWS Twin Cities, MN

August 10, 2020Carver County, Hennepin County, Scott County, Minnesota

NWS Twin Cities, MN issued this flash flood warning at Aug 10, 2020, 1:48 AM CDT for Carver County, Hennepin County, Scott County, Minnesota. It was in force for 4 hr. 3 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: Aug 10, 2020, 1:48 AM CDT (06:48 UTC)
Expired: Aug 10, 2020, 6:02 AM CDT
In force: 4 hr
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Flood severity: None

Counties Carver County, MN, Hennepin County, MN, Scott County, MN

The radar

The Minneapolis radar (KMPX), 4 km from the middle of the area, began a volume at 06:51 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
Aug 10, 5:00 AM CDT	HEAVY RAIN 2.61	2 Wnw Richfield, MN	COCORAHS STATION MN-HN-78 RICHFIELD 1WNW.
Aug 10, 5:00 AM CDT	HEAVY RAIN 3.24	2 Sw Minnetonka, MN	COCORAHS STATION MN-HN-156 LAKE MINNETONKA 1WSW.
Aug 10, 6:00 AM CDT	HEAVY RAIN 3.07	2 W New Hope, MN	COCORAHS STATION MN-HN-30 PLYMOUTH 2ENE.

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, 6.8 hours before the alert went out and 6 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: 2342 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 1184 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 168 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 10.5

Open this sounding in Storm Lab

The text

As transmitted.

389 
WGUS53 KMPX 100648
FFWMPX
MNC019-053-139-101245-
/O.NEW.KMPX.FF.W.0016.200810T0648Z-200810T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Twin Cities/Chanhassen MN
148 AM CDT Mon Aug 10 2020

The National Weather Service in The Twin Cities has issued a

* Flash Flood Warning for...
  Southern Hennepin County in east central Minnesota...
  Northeastern Scott County in east central Minnesota...
  Northeastern Carver County in east central Minnesota...

* Until 745 AM CDT.

* At 147 AM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have 
  already fallen and an additional inch or two is possible. Flash 
  flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Minneapolis, St. Paul, Bloomington, Plymouth, Eden Prairie,
  Burnsville, Minnetonka, Edina, St. Louis Park, Shakopee, Richfield
  and Savage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 4480 9373 4484 9380 4493 9384 4498 9380
      4498 9377 4502 9376 4505 9340 4499 9321
      4488 9318 4481 9325 4479 9333 4475 9333
      4475 9346

$$

JRB

2 follow-up statements

534 
WGUS73 KMPX 100938
FFSMPX

Flash Flood Statement
National Weather Service Twin Cities/Chanhassen MN
438 AM CDT Mon Aug 10 2020

MNC019-053-139-101245-
/O.CON.KMPX.FF.W.0016.000000T0000Z-200810T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hennepin MN-Scott MN-Carver MN-
438 AM CDT Mon Aug 10 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 AM CDT FOR
SOUTHERN HENNEPIN...NORTHEASTERN SCOTT AND NORTHEASTERN CARVER
COUNTIES...

At 437 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. 4 to 6 inches of rain have fallen 
overnight, and this could lead to flooding.

Some locations that will experience flooding include...
Minneapolis, St. Paul, Bloomington, Plymouth, Eden Prairie,
Burnsville, Minnetonka, Edina, St. Louis Park, Shakopee, Richfield
and Savage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 4480 9373 4484 9380 4493 9384 4498 9380
      4498 9377 4502 9376 4505 9340 4499 9321
      4488 9318 4481 9325 4479 9333 4475 9333
      4475 9346

$$

JRB

401 
WGUS73 KMPX 101102
FFSMPX

Flash Flood Statement
National Weather Service Twin Cities/Chanhassen MN
602 AM CDT Mon Aug 10 2020

MNC019-053-139-101111-
/O.CAN.KMPX.FF.W.0016.000000T0000Z-200810T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hennepin MN-Scott MN-Carver MN-
602 AM CDT Mon Aug 10 2020

...THE FLASH FLOOD WARNING FOR SOUTHERN HENNEPIN...NORTHEASTERN SCOTT
AND NORTHEASTERN CARVER COUNTIES IS CANCELLED...

The heavy rain has ended...and flooding is no longer expected to 
pose a threat as the water recedes. Please continue to heed any 
remaining road closures.

LAT...LON 4480 9373 4484 9380 4493 9384 4498 9380
      4498 9377 4502 9376 4505 9340 4499 9321
      4488 9318 4481 9325 4479 9333 4475 9333
      4475 9346

$$

LS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 7:52 PM CDT	Special Weather Statement	MPX	Hennepin	23 min
Aug 9, 8:13 PM CDT	Special Weather Statement	MPX	Hennepin	47 min
Aug 9, 8:47 PM CDT	Special Weather Statement	MPX	Scott	88 min
Aug 9, 9:00 PM CDT	Special Weather Statement	MPX	Scott	30 min
Aug 9, 9:21 PM CDT	Special Weather Statement	MPX	Carver	54 min
Aug 9, 9:30 PM CDT	Severe Thunderstorm Warning	MPX	Carver	45 min
Aug 9, 9:39 PM CDT	Severe Thunderstorm Warning	MPX	Hennepin, Scott	51 min
Aug 9, 10:14 PM CDT	Special Weather Statement	MPX	Hennepin	46 min
Aug 9, 10:27 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Hennepin, Sherburne, Wright	48 min
Aug 9, 10:27 PM CDT	Severe Thunderstorm Warning	MPX	Dakota, Hennepin, Scott	27 min
Aug 9, 10:48 PM CDT	Severe Thunderstorm Warning	MPX	Wright	57 min
Aug 9, 11:16 PM CDT	Severe Thunderstorm Warning	MPX	Hennepin	44 min
Aug 9, 11:40 PM CDT	Severe Thunderstorm Warning	MPX	Wright	50 min
Aug 9, 11:56 PM CDT	Severe Thunderstorm Warning	MPX	Hennepin	49 min
Aug 10, 12:28 AM CDT	Severe Thunderstorm Warning	MPX	Wright	32 min
Aug 10, 12:41 AM CDT	Severe Thunderstorm Warning	MPX	Hennepin	49 min
Aug 10, 12:42 AM CDT	Special Weather Statement	MPX	Hennepin	63 min
Aug 10, 12:54 AM CDT	Severe Thunderstorm Warning	MPX	Carver, Hennepin	51 min
Aug 10, 1:21 AM CDT	Severe Thunderstorm Warning	MPX	Dakota, Hennepin, Scott	39 min
Aug 10, 1:29 AM CDT	Special Weather Statement	MPX	Hennepin	61 min
Aug 10, 1:57 AM CDT	Severe Thunderstorm Warning	MPX	Dakota, Hennepin, Washington	48 min
Aug 10, 2:04 AM CDT	Severe Thunderstorm Warning	MPX	Meeker, Wright	26 min
Aug 10, 2:08 AM CDT	Severe Thunderstorm Warning	MPX	Rice, Scott	37 min
Aug 10, 2:20 AM CDT	Severe Thunderstorm Warning	MPX	Dakota, Scott	40 min
Aug 10, 2:31 AM CDT	Severe Thunderstorm Warning	MPX	Wright	44 min
Aug 10, 2:41 AM CDT	Severe Thunderstorm Warning	MPX	Dakota, Rice, Scott	49 min
Aug 10, 2:43 AM CDT	Severe Thunderstorm Warning	MPX	Carver, Scott	32 min
Aug 10, 3:06 AM CDT	Severe Thunderstorm Warning	MPX	Anoka, Hennepin	54 min
Aug 10, 3:15 AM CDT	Severe Thunderstorm Warning	MPX	Kanabec, Mille Lacs	45 min
Aug 10, 3:29 AM CDT	Severe Thunderstorm Warning	MPX	Dakota, Goodhue, Rice	46 min
Aug 10, 3:34 AM CDT	Special Weather Statement	MPX	Sherburne	56 min
Aug 10, 3:46 AM CDT	Severe Thunderstorm Warning	MPX	Rice	44 min
Aug 10, 3:58 AM CDT	Special Weather Statement	MPX	Dakota	32 min
Aug 10, 4:10 AM CDT	Severe Thunderstorm Warning	MPX	Goodhue, Rice	50 min
Aug 10, 4:16 AM CDT	Severe Thunderstorm Warning	MPX	Steele, Waseca	59 min
Aug 10, 5:08 AM CDT	Severe Thunderstorm Warning	MPX	Freeborn, Steele, Waseca	22 min
Aug 10, 5:27 AM CDT	Severe Thunderstorm Warning	MPX	Goodhue, Rice	17 min
Aug 10, 7:44 AM CDT	Special Weather Statement	MPX	Blue Earth	31 min
Aug 10, 8:03 AM CDT	Special Weather Statement	MPX	Waseca	27 min
Aug 10, 8:10 AM CDT	Severe Thunderstorm Warning	MPX	Waseca	35 min
Aug 10, 8:36 AM CDT	Severe Thunderstorm Warning	MPX	Freeborn, Steele	28 min

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.