Stormy Monday: Heavy downpours, severe threat

The car or train may get you into work this morning. The kayak may be the preferred mode of transport home during PM rush.

A spinning low pressure system over North Dakota cuts into a tropical air mass over Minnesota today. The result will be scattered lines of heavy thunderstorms with the potential for tropical downpours and flash floods. There is also a slight risk a few of the storms may go severe this afternoon and evening, with high winds and hail.

Here's a quick rundown on what we can expect today.

  • AM fog gradually fades south but lingers north and near Lake Superior

  • Sticky tropical air mass in place over central and southern Minnesota with dew points near 70 degrees

  • Scattered T-storms can pop at any time, but more organized lines of storms will favor PM and evening in eastern Minnesota and metro

  • Slow moving storms have potential for heavy, flooding multi-inch rainfall totals

  • Slight risk for severe storms with hail and high winds late PM & evening from Twin Cities south


Before you keep reading ...

Did you know that MPR News is supported by Members? Gifts from individuals power the headlines, clarity and context found here. Give during the Fall Member Drive to become a Member today.

Slow moving low

Here's the weather culprit, or savior depending on your rainfall perspective. A slow moving low pressure system spins across Minnesota today and tonight triggering waves of rain and T-storms.

1818 allfcsts_loop_ndfd (1)

NOAA has added a slight risk for severe storms over the metro later today.

1818 risk

The atmosphere over the Twin Cities and eastern Minnesota is juiced with moisture today. Precipitable water (the total water content) overhead is running close to 1.75" near the metro and in western Wisconsin today. Since storms can pull in water from the surrounding environment, slow moving storms tap into the moisture and can produce multi-inch rainfall totals.

Keep in mind heavy rainfall is highly localized, but here's a wider look at potential rainfall totals this week.

1818 qpff

The best shot at a gully washer today in the metro appears to be PM into the early evening hours.

1818 qpf
Iowa State University

The La Crosse NWS details the threat for flooding rains later today and this evening.

1818 lse
NWS La Crosse

The initial storm waves already dumped flash flooding rainfall totals near Miesville and Hampton southeast of the metro, and near Gluek in west central Minnesota over the weekend. Here's the doppler storm total rainfall alogorithim, which paints a 4" to 7" bull's eye over Miesville.

1818 stp2 metro
Weather Underground

The deluge produced a nearly 3 foot rise in the Cannon River at Welch early this morning.

1818 cannon

Steamy State Fair opener - Hints of September next week? 

The longer range model output calls for a summer like week this week, followed by a potential temperature crash next week. Here's the European model version of events.

1818 7

Some of the guidance hints at temps in the upper 30s outside the metro for morning lows next week. This may be over done, but it get's our attention. Is it a Euro model hiccup, or the first real shot of September air heading south?

Stay tuned.