Updraft® - Minnesota Weather News

Stormy weather for a few more days; local flooding possible

You might have been awakened a time or two overnight Monday into Tuesday as persistent thunderstorms with heavy rain along with continuous thunder and lightning whacked the Twin Cities area and other parts of central and then southeastern Minnesota.

Rainfalls in the Twin Cites area for the 24 hours ending at 7 a.m. on Tuesday were about 1.5 inches for the official amount at Minneapolis-St. Paul International Airport, a bit more than an inch at Eden Prairie and St. Paul, but just a half inch at Crystal.

My backyard rain gauge in Minneapolis collected just over 2.1 inches of rain that will make the lawn and gardens happy.

Meanwhile, a convective system of strong thunderstorms from South Dakota is racing eastward across the southern part of Minnesota and will reach the Twin Cities this morning. Strong, gusty winds are possible along the leading edge.

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The atmosphere will take some time to recover after the morning rounds of thunderstorms finish rolling through. Then there will be a marginal risk of severe weather later today or tonight in Iowa and part of the southern edge of Minnesota.

sept 18 - svr
Isolated severe storms are possible later Tuesday or Tuesday night. NOAA Storm Prediction Center

Tuesday will be a rather cool day thanks to rain, clouds and a northeast breeze. High temperatures will be just in the 50s in the northeastern part of the state. Much of Minnesota will see 60s this afternoon with maybe a few low 70s in the southeast. The Twin Cities should have a high around 67 degrees.

Rounds of heavy rain coming

A slowly-moving weather pattern means that we should look for rounds of heavy rain and thunderstorms, especially across the southern half of our state, until about Thursday night. Rainfall totals are likely to be impressive, with some areas getting soaked by 3 to 5 inches over the next few days.

While the exact locations that will pick up the maximum rainfalls are uncertain, there is rather high confidence that this period will produce a lot of rain.

Sept 18 - wet wx continues
Forecast rainfalls through Thursday. Twin Cities National Weather Service

Localized flooding possible

Some of the rainfalls will be quite heavy, and it looks as though some of those are likely to occur at night when the nocturnal low level jet stream kicks in. Here is an outlook for when excessive rainfall might produce localized flash flooding over the next few days:

Sept 18 - excessive rain outlook
The risk of excessive rainfall this week. Twin Cities National Weather Service

The potential for flash flooding on Wednesday should extend eastward across Wisconsin to Green Bay.

Sept 18 - wed fcst map
Forecast surface weather map for Wednesday. NOAA Weather Prediction Center

Thursday will not only bring more rain but will shift the higher amounts farther northeast. The pattern also favors an increased chance of severe weather across a broad area including southeastern Minnesota as well as most of Iowa and Wisconsin Thursday afternoon.

Sept 18 - Th severe risk
Forecast surface weather map for Thursday. NOAA Weather Prediction Center

Bright and shiny Friday-Sunday

Clearing and cool weather should come our way for Friday when the Twin Cities might not warm above the low 60s. Then look for a very pleasant fall weekend with warming temperatures.