Rain, more rain, too much rain; flash flooding likely

The advertised plume of deep moisture from the Gulf of Mexico has arrived in Minnesota. Showers and thunderstorms, some with very heavy rain, broke out across southern Minnesota Monday night.

Flash flooding, including mudslides and rapidly-rising water, struck Houston County in the southeastern corner of the state.

Rain was already rather widespread southeast and northwest of the Twin Cities Tuesday morning.

More heavy rain on the way

The conveyor belt of showers and storms will become more vigorous as we go through Tuesday and into Tuesday evening.

The meteorological set-up for this event will tend to line up storms to train over the same areas and cause significant accumulations of rainfall. Rainfalls of 2 to 4 inches are likely. Some spots might pick up more than 5 or 6 inches if a rain train persists.

While there is some uncertainty as to exactly where these maximum rainfalls will occur, forecast models are targeting much of south central and southeastern Minnesota along with west central Wisconsin as areas for concern Tuesday and Tuesday tonight.

Dangerous flash flooding likely

Much of this rain is likely to fall on areas that have had more than their share of rain recently. The ground is soggy. Additional heavy rain can easily cause flash flooding, which means rapidly rising water overflowing streams and flooding roads and maybe basements.

While the southeastern corner of the state might be the most susceptible to more flooding, the amount of rain expected to fall might cause flooding problems in many spots.

The National Weather Service has issued flash flood watches through Tuesday night basically for areas southeast of a line from Worthington in southwestern Minnesota to St. Paul to Rice Lake, Wis. Dakota County in the southeast metro and St. Croix and Pierce Counties in west central Wisconsin are included in the watch.

Severe weather possible?

Enhanced atmospheric dynamics later today will generate a chance of severe storms in the southeast.

Gordon intensifying toward the Gulf Coast

Topical Storm Gordon is a strong tropical storm with maximum sustained winds of 65 mph Tuesday morning. Gordon is forecast to become a Category 1 hurricane as it strengthens over the Gulf of Mexico before making landfall Tuesday night.

Hurricane warnings have been posted for coastal areas of Mississippi and Alabama and are bordered by tropical storm warnings. Very dangerous storm surges of 2 to 5 feet are likely.

Hurricane Norman

Meanwhile, out in the Pacific Ocean, Category 1 Hurricane Norman is tracking westward. That path would take it directly toward Hawaii, but pressure and wind patterns in the area are forecast to turn Norman to the right so it should bypass the islands.

Big changes on Wednesday

Although a few showers might linger in southeastern Minnesota on Wednesday, a cold front will slide southeastward and allow much drier air to cover the state. Look for a lot of dew points in the 40s and 50s from tomorrow through the weekend and beyond.

Farther south, heavy rain from Tropical Storm Gordon weakening inland could cause flooding in the southern Mississippi River Valley.