Alert archive / Minnesota / Flash Flood Warnings in 2018

Flash Flood Warning 22, NWS La Crosse, WI

September 4, 20184 counties in Minnesota

NWS La Crosse, WI issued this flash flood warning at Sep 4, 2018, 6:22 PM CDT for 4 counties in Minnesota. It was in force for 3 hr. 23 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
Sep 4, 2018, 6:22 PM CDT (23:22 UTC)
Expired
Sep 4, 2018, 9:15 PM CDT
In force
3 hr
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Flood severity
None

Counties Dodge County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN

The radar

The La Crosse radar (KARX), 101 km from the middle of the area, began a volume at 23:25 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
Sep 4, 6:32 PM CDTFLOOD1 Se Rochester, MNSTREET FLOODING IN PARTS OF CITY
Sep 4, 6:36 PM CDTHEAVY RAIN 1.92 W Rochester, MNRAIN TOTAL SINCE 4 PM.
Sep 4, 6:42 PM CDTHEAVY RAIN 2.623 Sw Rochester, MN
Sep 4, 6:50 PM CDTFLOOD1 Nw Rochester, MNLOTS OF STREET FLOODING REPORTS INCLUDING STALLED CARS AND PARKING LOTS UNDER WATER
Sep 4, 7:00 PM CDTHEAVY RAIN 3.754 Ese Douglas, MNDELAYED REPORT. RELAYED VIA SOCIAL MEDIA.
Sep 4, 7:05 PM CDTHEAVY RAIN 3.754 Nw Rochester, MNSINCE 630 AM TODAY
Sep 4, 7:30 PM CDTHEAVY RAIN 2.27Wabasha, MNCOCORAHS STATION MN-WB-7, WABASHA.
Sep 4, 7:36 PM CDTFLOOD2 Ne Rochester, MNSTREET FLOODING AT 11TH AVE NEAR 2ND ST NE. CARS STRANDED IN THIS AREA.
Sep 4, 7:42 PM CDTHEAVY RAIN 3.12Mantorville, MNRELAYED VIA BROADCAST MEDIA.
Sep 4, 7:43 PM CDTFLASH FLOOD2 E Zumbro Falls, MNWATER OVER PARTS OF HIGHWAY 60. ALSO SOME SECONDARY ROADS AROUND THE COUNTY HAVE WASHOUTS.
Sep 4, 7:45 PM CDTFLOODHayfield, MNSTREET FLOODING IN TOWN
Sep 4, 7:45 PM CDTHEAVY RAIN 3.52 Ne Rochester, MN
Sep 4, 7:51 PM CDTHEAVY RAIN 2.932 Nnw Rochester, MN
Sep 4, 7:52 PM CDTHEAVY RAIN 2.82Kasson, MNRELAYED VIA BROADCAST MEDIA.
Sep 4, 7:55 PM CDTHEAVY RAIN 4.12 S Kasson, MNRELAYED VIA BROADCAST MEDIA.
Sep 4, 7:59 PM CDTHEAVY RAIN 43 Nw Rochester, MNREPORT VIA SOCIAL MEDIA.
Sep 4, 8:10 PM CDTHEAVY RAIN 4.053 Ne Rochester, MNRAIN FELL IN 2 HOURS.
Sep 4, 8:21 PM CDTHEAVY RAIN 3.642 Se Wabasha, MNRELAYED VIA SOCIAL MEDIA.
Sep 4, 8:33 PM CDTHEAVY RAIN 4.753 Se Douglas, MN
Sep 4, 8:37 PM CDTFLOODByron, MNSOME ROADS CLOSED IN BYRON
Sep 4, 8:46 PM CDTFLOOD2 Nne Austin, MNINTERSTATE 90 CLOSED IN TOWN FROM FLOODING.
Sep 4, 8:52 PM CDTHEAVY RAIN 4.83 Nw Rochester, MN
Sep 4, 8:58 PM CDTHEAVY RAIN 4.03Mantorville, MN

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, 11.4 hours before the alert went out and 125 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 2018-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 106 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2018-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 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
106 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
667 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

603 
WGUS53 KARX 042322
FFWARX
MNC039-099-109-157-050215-
/O.NEW.KARX.FF.W.0022.180904T2322Z-180905T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service La Crosse WI
622 PM CDT TUE SEP 4 2018

The National Weather Service in La Crosse has issued a

* Flash Flood Warning for...
  Olmsted County in southeastern Minnesota...
  Mower County in southeastern Minnesota...
  Wabasha County in southeastern Minnesota...
  Dodge County in southeastern Minnesota...

* Until 915 PM CDT.

* At 621 PM CDT, Doppler radar indicated heavy rain across the 
  warned area. Flash flooding is expected to begin shortly. Street 
  flooding has been reported in the Rochester area. More 
  thunderstorms are expected to move over the area through the 
  evening hours.

* Some locations that will experience flooding include...
  Rochester, Austin, Dodge Center, Wabasha, Mantorville, Kasson,
  Stewartville, Byron, Plainview, Eyota, Hayfield, Oronoco, Grand 
  Meadow, Elgin,Mazeppa, West Concord, Dover, Brownsdale and 
  Claremont.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4419 9304 4419 9255 4435 9255 4437 9254
      4437 9243 4445 9243 4445 9224 4440 9206
      4433 9192 4429 9193 4427 9190 4419 9187
      4419 9208 4399 9208 4385 9224 4385 9245
      4373 9245 4364 9260 4350 9305

$$

DTJ
2 follow-up statements
229 
WGUS73 KARX 050034
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
734 PM CDT TUE SEP 4 2018

MNC039-099-109-157-050215-
/O.CON.KARX.FF.W.0022.000000T0000Z-180905T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Olmsted MN-Mower MN-Wabasha MN-Dodge MN-
734 PM CDT TUE SEP 4 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
OLMSTED...MOWER...WABASHA AND DODGE COUNTIES...

At 729 PM CDT, spotter and public reports heavy rain has fallen and 
flooding is occurring in the city of Rochester. 2 to 4 inches of 
rain has fallen with more shower and thunderstorms with moderate to 
heavy rain moving into the warned area.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4419 9304 4419 9255 4435 9255 4437 9254
      4437 9243 4445 9243 4445 9224 4440 9206
      4433 9192 4429 9193 4427 9190 4419 9187
      4419 9208 4399 9208 4385 9224 4385 9245
      4373 9245 4364 9260 4350 9305

$$

DTJ
498 
WGUS73 KARX 050141
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
841 PM CDT TUE SEP 4 2018

MNC039-099-109-157-050215-
/O.CON.KARX.FF.W.0022.000000T0000Z-180905T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Olmsted MN-Mower MN-Wabasha MN-Dodge MN-
841 PM CDT TUE SEP 4 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR
OLMSTED...MOWER...WABASHA AND DODGE COUNTIES...

At 837 PM CDT, spotters, law enforcement, broadcast media and public 
have reported flooding mainly in urban areas across the warned area. 
Rainfall amounts of 2 to 4 inches have been reported. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4419 9304 4419 9255 4435 9255 4437 9254
      4437 9243 4445 9243 4445 9224 4440 9206
      4433 9192 4429 9193 4427 9190 4419 9187
      4419 9208 4399 9208 4385 9224 4385 9245
      4373 9245 4364 9260 4350 9305

$$

DTJ

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 3, 9:17 PM CDTFlash Flood WarningARXHouston9 hr
Sep 4, 4:00 AM CDTFlash Flood WatchARXDodge, Fillmore, Houston, Mower, Olmsted, Wabasha and 1 more33 hr
Sep 4, 11:23 AM CDTRiver Flood WarningARXMower62 hr
Sep 4, 11:23 AM CDTRiver Flood WarningARXHouston17 hr
Sep 4, 2:34 PM CDTSpecial Weather StatementARXMower56 min
Sep 4, 3:01 PM CDTSpecial Weather StatementARXDodge, Olmsted, Wabasha, Winona89 min
Sep 4, 4:47 PM CDTSevere Thunderstorm WarningARXOlmsted, Wabasha, Winona30 min
Sep 4, 6:19 PM CDTSpecial Weather StatementARXDodge, Fillmore, Mower, Olmsted, Wabasha, Winona86 min

Nearby

Flash Flood Warnings in Minnesota, 2018Every flash flood warning in 2018

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.