Alert archive / Minnesota / Flash Flood Watches in 2018

Flash Flood Watch 8, NWS Twin Cities, MN

September 19, 201813 counties in Minnesota

NWS Twin Cities, MN issued this flash flood watch at Sep 19, 2018, 10:39 AM CDT for 13 counties in Minnesota. It took effect at Sep 19, 2018, 7:00 PM CDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
Sep 19, 2018, 10:39 AM CDT (15:39 UTC)
In effect from
Sep 19, 2018, 7:00 PM CDT
Expired
Sep 20, 2018, 3:13 AM CDT
In force
8 hr
Issued by
NWS Twin Cities, MN
Flood severity
None

Counties Blue Earth County, MN, Brown County, MN, Faribault County, MN, Freeborn County, MN, Goodhue County, MN, Le Sueur County, MN, Martin County, MN, Nicollet County, MN, Redwood County, MN, Rice County, MN, Steele County, MN, Waseca County, MN, Watonwan County, MN

The radar

The Minneapolis radar (KMPX), 89 km from the middle of the area, began a volume at 15:38 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 12:00Z, 3.7 hours before the alert went out and 89 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 2018-09-19Temperature 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 12:00Z on 2018-09-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.1939587897117136Sfc1 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
536 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
164 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

225 
WGUS63 KMPX 191539
FFAMPX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Twin Cities/Chanhassen MN
1039 AM CDT Wed Sep 19 2018

...HEAVY RAIN AND FLOODING RISK INCREASING TONIGHT ACROSS SOUTHERN
MINNESOTA...

.The risk for heavy rain and flooding has increased across
southern Minnesota. Thunderstorms should develop near I-90 later
this evening, and continue through Thursday morning. Forecast
rainfall amounts of 3 to 4 inches are expected, but locally higher
amounts of 6 inches or more are certainly possible. 

Anyone living or camping in flood prone areas should be prepared
to move to higher ground if a flood warning is issued. Anyone
traveling overnight should use caution while driving, and turn
around if they encounter water covered roads. Most flood
fatalities occur when vehicles drive into flood waters. Remember,
turn around and don't drown.

MNZ073>078-082>085-091>093-192345-
/O.NEW.KMPX.FF.A.0008.180920T0000Z-180920T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-
Including the cities of Redwood Falls, New Ulm, St Peter, 
Le Sueur, Faribault, Red Wing, St James, Mankato, Waseca, 
Owatonna, Fairmont, Blue Earth, and Albert Lea
1039 AM CDT Wed Sep 19 2018

...FLASH FLOOD WATCH IN EFFECT FROM 7 PM CDT THIS EVENING THROUGH
THURSDAY AFTERNOON...

The National Weather Service in Twin Cities/Chanhassen has issued
a

* Flash Flood Watch for portions of south central Minnesota, 
  southeast Minnesota, and southwest Minnesota, including the 
  following areas, in south central Minnesota, Blue Earth, 
  Brown, Faribault, Freeborn, Le Sueur, Martin, Nicollet, Rice, 
  Steele, Waseca, and Watonwan. In southeast Minnesota, Goodhue. 
  In southwest Minnesota, Redwood. 

* From 7 PM CDT this evening through Thursday afternoon

* Thunderstorms with very heavy rain possible overnight.

* Urban and small stream flooding is possible tonight which could
  impact travel. This could lead to river flooding later in the
  week.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

jrb
2 follow-up statements
766 
WGUS63 KMPX 192339
FFAMPX

Flood Watch
National Weather Service Twin Cities/Chanhassen MN
639 PM CDT Wed Sep 19 2018

...ELEVATED HEAVY RAIN AND FLOODING RISK TONIGHT ACROSS SOUTHERN 
MINNESOTA...

.The risk for heavy rain and flooding remains elevated across 
southern Minnesota. Thunderstorms should develop near Interstate
90 later this evening and continue through Thursday morning. 
Forecast rainfall amounts of 3 to 4 inches are expected, but 
locally higher amounts of 6 inches or more are certainly possible.

Anyone living or camping in flood prone areas should be prepared
to move to higher ground if a flood warning is issued. Anyone
traveling overnight should use caution while driving, and turn
around if they encounter water covered roads. Most flood
fatalities occur when vehicles drive into flood waters. Remember,
turn around and don't drown.

MNZ073>078-082>085-091>093-200900-
/O.CON.KMPX.FF.A.0008.180920T0000Z-180920T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-
Including the cities of Redwood Falls, New Ulm, St Peter, 
Le Sueur, Faribault, Red Wing, St James, Mankato, Waseca, 
Owatonna, Fairmont, Blue Earth, and Albert Lea
639 PM CDT Wed Sep 19 2018

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY
AFTERNOON...

The Flash Flood Watch continues for

* Portions of south central Minnesota, southeast Minnesota, and 
  southwest Minnesota, including the following areas, in south 
  central Minnesota, Blue Earth, Brown, Faribault, Freeborn, Le 
  Sueur, Martin, Nicollet, Rice, Steele, Waseca, and Watonwan. 
  In southeast Minnesota, Goodhue. In southwest Minnesota, 
  Redwood. 

* Through Thursday afternoon

* Thunderstorms with very heavy rain possible overnight.

* Urban and small stream flooding is possible tonight which  
  could impact travel. This could lead to river flooding later  
  in the week. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$
875 
WGUS63 KMPX 200813
FFAMPX

Flood Watch
National Weather Service Twin Cities/Chanhassen MN
313 AM CDT Thu Sep 20 2018

MNZ073>078-082>085-091>093-200915-
/O.CAN.KMPX.FF.A.0008.000000T0000Z-180920T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-
Including the cities of Redwood Falls, New Ulm, St Peter, 
Le Sueur, Faribault, Red Wing, St James, Mankato, Waseca, 
Owatonna, Fairmont, Blue Earth, and Albert Lea
313 AM CDT Thu Sep 20 2018

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of south central Minnesota,
southeast Minnesota, and southwest Minnesota has been cancelled.

Rainfall overnight was not as heavy as anticipated, therefore the
flash flood watch has been cancelled. Light to moderate rain will
continue through the morning, with another round of thunderstorms
expected this afternoon as a cold front works through. Though 
heavy downpours are expected with the afternoon thunderstorms, 
they look to be moving fast enough to limit the threat for flash 
flooding.

$$

Nearby

Flash Flood Watches in Minnesota, 2018Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.