River flooding increases; potential for rain on Thursday

No downpours are in the forecast the next few days, which is good news for everyone affected by rising river levels. Areas that have snow cover will see it shrink a bit today.

On to the details.

Temperature trends

Sunday afternoon highs are expected to be in the 30s across roughly the northern third of Minnesota, with mostly 40s in central Minnesota. Southern Minnesota and the Twin Cities metro area could see highs in the upper 40s to the lower 50s. Our average March 24 high temp is 45 degrees in the Twin Cities metro area.

Monday highs will feature 30s north and 40s south:

Twin Cities metro area highs are projected to reach the lower 50s Tuesday, followed by lower 60s on Wednesday. Highs in the upper 50s are on tap for Thursday, then upper 40s on Friday.

Wednesday will be the warmest day of the week across most of Minnesota and western Wisconsin:

Thursday rain update

The southern part of the Twin Cities metro area could see a sprinkle or a bit of drizzle this Sunday morning. The best chance of Sunday morning light rain showers will be in far southern Minnesota. A few scattered rain showers could linger into early Sunday afternoon in parts of southeastern Minnesota.

Some meaningful rain could arrive in southern Minnesota late Wednesday night and continue through Thursday evening. The National Oceanic and Atmospheric Administration’s Global Forecast System model shows the potential precipitation pattern Wednesday evening through Thursday night:

NOAA GFS precipitation rate (mm/hour) Wednesday evening through Thursday night, via tropicaltidbits

The color chart to the right of the loop refers to the precipitation rate (mm per hour), not to the total amount of rain or snow.

Yes, this model run shows the rain transitioning to a bit of light snow before ending late Thursday night or early Friday. We’ll watch how the forecast models change as we get closer to Thursday.

As always, updated weather information can be heard on the Minnesota Public Radio Network, and you’ll also see updated weather info on the MPR News live weather blog.

Update on river levels and flooding

Our spring snow melt continues to cause flooding in many locations.

As of Sunday morning, many spots along the Minnesota River are at moderate flood stage. The Minnesota River is expected to reach major flood stage at Savage on Monday, at Montevideo on Tuesday and at New Ulm on Thursday. The Cottonwood River at New Ulm is already at major flood stage, and it’s forecast to remain at major flood stage until Friday.

Many areas have flood warnings. You can get flood warning updates by clicking on any location on the National Weather Service Twin Cities website. Areas with flood warnings are shaded green on the NWS main page, and here’s how the map looked Sunday morning:

NWS Twin Cities

By the way, the dense fog advisory that includes Fergus Falls expires at 11 a.m. this Sunday.

The Mississippi River at St. Paul has reached moderate flood stage, and it’s expected to reach major flood stage on Monday. Here’s the Sunday morning NWS flood warning update for the Mississippi River at St. Paul:

243 AM CDT Sun Mar 24 2019

The Flood Warning continues for
The Mississippi River at St. Paul.
* until further notice.
* At 2:00 AM Sunday the stage was 14.7 feet.
* Minor flooding is occurring and Major flooding is forecast.
* Flood stage is 14.0 feet.
* Forecast…The river will continue rising to near 20.5 feet by
Friday early afternoon. Additional rises may be possible
thereafter.
* Impact…At 18.0 feet…Warner Road may become impassable due to
high water.
* Impact…At 17.5 feet…Harriet Island begins to become submerged.
* Impact…At 14.0 feet…Portions of the Lilydale park area begin to
experience flooding.
* Impact…At 13.3 feet…Water begins to encroach on Water St.

You can click on any location on the NWS Advanced Hydrologic Prediction Service  (AHPS) site to get hydrographs of recent and forecast river levels. Some locations list levels in feet above sea level, others list levels in feet above a local reference point.

Here’s the Sunday morning hydrograph for the Mississippi River at St. Paul:

NOAA/NWS/U.S. Geological Survey

The 20.5 foot level late in the week would be the seventh highest Mississippi River level ever recorded at the St. Paul gauge:

NOAA/NWS/USGS data for the Mississippi River at St. Paul

Water is already covering most of the steps in front of the pavilion at Harriet Island in St. Paul:

March 24, 2019     City of St. Paul webcam

And water also covers parts of Raspberry Island:

March 24, 2019     City of St. Paul webcam March 24, 2019    City of St. Paul webcam

You can imagine what this area will look like as the river rises another 5.2 feet by Friday.

Here’s the hydrograph for the St. Croix River at Stillwater:

NOAA/NWS/USGS

Projected river levels are updated on a regular basis, so check back to the AHPS site and the NWS point forecasts for the latest info on the rivers near you.

The NWS also posts some flooding details here.

If you’d like to scroll through hydrographs along a certain river, check 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.