Autumnal beauty today; NWS survey adds to Thursday tornado tally

Our first Sunday of astronomical autumn will be a keeper.

There’ll be plenty of sunshine in about the southern half of Minnesota, with highs in the 70s.

It’s nice when pleasant weather happens on a weekend!

Temperature trends

Sunday highs in northern Minnesota will range from the 40s near the Canadian border to 60s in places like Moorhead, Brainerd and Hinckley.

On Monday, Minnesota highs will range from 50s northwest to 70s southeast:

Twin Cities metro area highs drop from the lower 70s on Monday to the lower 60s Tuesday and Wednesday. We might only hit around 60 degrees on Thursday and Friday.

Fall color

We like to keep track of fall color this time of year.

The weekend fall color report from the Minnesota Department of Natural Resources shows quite a bit of fall color  in parts of northern Minnesota:

Minnesota DNR

Keep in mind that all deciduous trees are included in the fall color report, not just maples.

Rain chances

North-central and northeastern Minnesota could see a few showers at times as we go through Sunday.

Updated weather information can be heard on the Minnesota Public Radio Network, and you can see updated weather info on the MPR news live weather blog.

Some showers/isolated thunderstorms are expected to move into western Minnesota overnight Sunday night and spread eastward on Monday.  The Twin Cities metro might not see a shower/t-storm until mid to late afternoon on Monday, with scattered showers/t-storms Monday evening.

The National Oceanic and Atmospheric Administration’s North American Mesoscale forecast model shows the potential rain pattern Sunday evening  through Monday night:

NOAA NAM simulated radar from Sunday evening through Monday night, via tropicaltidbits

The color chart to the right of the loop refers to the strength of the signal that returns to the radar, not to the amount of rain.

River flooding

The torrential rains over southern Minnesota this past week have caused river flooding in some areas.

Flood warnings have been issued for the green-shaded areas on this map, which is posted on the home page of the National Weather Service Twin Cities office:

NWS Twin Cities

You can click on areas of interest on the NWS home pages for the latest river forecasts.

The Saturday evening NWS flood statement looked like this:

Flood Statement
National Weather Service Twin Cities/Chanhassen MN
757 PM CDT Sat Sep 22 2018

…The flood warning continues for the following rivers in
Minnesota…

Cottonwood River at New Ulm affecting Brown County
Minnesota River at Henderson MN19 affecting Le Sueur…Scott and
Sibley Counties
Redwood River near Redwood Falls affecting Redwood County
…The flood warning continues for the following river in
Minnesota..
Minnesota River near Jordan affecting Carver and Scott Counties

.Overview…

This river forecast is based on preciptation over the past 24 hours
and forecast precipitation over the next 24 hours. Additional
rainfall could cause river levels to rise higher than predicted.
The National Weather Service will monitor this situation and
issue followup statements as conditions or forecasts change.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

Do not drive cars through flooded areas. Turn Around…Don`t Drown.

Stay tuned to NOAA Weather Radio or your local radio or TV station
for the latest information concerning this flood event.

Here’s the Saturday evening update for the Minnesota River near Jordan:

MNC019-139-240656-
/O.CON.KMPX.FL.W.0038.180925T0730Z-000000T0000Z/
/JDNM5.2.ER.180925T0730Z.180928T0000Z.000000T0000Z.NO/
757 PM CDT Sat Sep 22 2018

The Flood Warning continues for
The Minnesota River near Jordan.
* from late Monday night until further notice.
* At 6:45 PM Saturday the stage was 20.7 feet.
* Moderate flooding is forecast.
* Flood stage is 25.0 feet.
* Forecast…Rise above flood stage by Tuesday morning and
continue to rise to near 28.2 feet by Thursday evening.
* Impact…At 26.7 feet…The bridge at Scott County Road 9 and Carver
County Road 11/Jonathan Carver Parkway will be closed.
* Impact…At 25.0 feet…Low lying areas and some roads along the
river begin to flood and private sanitary sewers may experience
problems.

The NWS will issue flood warning updates today.

You can also click on any location on the NWS Advanced Hydrologic Prediction Service site to get hydrographs of recent and forecast river levels.

Here’s the hydrograph for the Cottonwood River at New Ulm, Minnesota, which is more than four feet above flood stage this weekend:

NOAA/NWS/USGS

Tornado survey update

The National Weather Service hasn’t completed their survey of the Thursday evening tornado damage in southern Minnesota, but they gave us an update Saturday evening.

The NWS has confirmed ten tornado tracks so far, but they indicate that they may combine tornado tracks together in a couple of areas to form one (longer) tornado track. The tornado total could also rise as they survey more areas over the next few days.

Here’s the most recent NWS tornado summary for September 20:

Public Information Statement…UPDATED
National Weather Service Twin Cities/Chanhassen MN
1030 PM CDT Sat Sep 22 2018

…A BRIEF SUMMARY OF THE SEPTEMBER 20TH TORNADOES…

All of this information is preliminary and will likely change as
more information is gathered. Some tornadoes may be combined to
form longer tracks which may reduce the total number below. Some
ratings are being assessed for modification. Other locations have
yet to be surveyed and more tornadic areas could be added to this
list.

1.) Just west of Ceylon, MN (Martin Co.): Brief EF0

2.) Granada, MN (Martin Co.): EF1

3.) Northwest of Janesville, MN near the Blue Earth/Waseca County
line to Waterville, MN (Waseca and Le Sueur Co.): EF1

4.) Morristown, MN (Rice Co.): EF2

5.) Northwest of Faribault near Robards Lake to I-35 (Rice Co.):
EF1

6.) Northfield, MN (Rice Co.) to Cannon Falls (Goodhue Co.): EF1

7.) Cannon River Wilderness area (Rice Co.) to between Dennison
and Stanton, MN (Goodhue Co.): EF1

8.) Southwest side of Cannon Falls, MN: EF1. This one could
eventually be combined with #7 upon further assessment.

9.) South of Dundas, MN to southeast of Northfield, MN (Rice Co.):
EF1. This one could be combined with #5 upon further assessment.

10.) Medford, MN (on Steele/Rice Co border) to between Nerstrand
and Kenyon, MN (Goodhue co.): EF1

Other areas of interest: Cannon Falls city eastward into Pierce
County, WI and Owatonna northeastward toward Zumbrota.

The NWS will be posting updated information on the September 20 tornadoes here.

Programming note

You can hear my live weather updates on Minnesota Public Radio at 7:49 a.m. Thursdays and Fridays, and at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.