Canadian cooldown has begun

It's time to dig your fall jacket out of your closet if you have not done so already. Chillier weather has spread southeastward across Minnesota.

The temperature had dropped to the freezing mark at 6 a.m. Friday morning in Bemidji and Fosston and northwestern Minnesota and even in Staples in the central part of the state.

Friday afternoon will be a bit on the chilly side with a gusty breeze. Look for highs from the low 40s to mid 50s. The Twin Cities should warm to only about 52, much cooler than the average high of 66 for this date. Isolated showers and even a few flurries are likely across northern Minnesota.

Expect the chilly weather to hang on through the upcoming weekend.

There will be frost, and lots of it

The thermal nadir will occur Saturday morning. A combination of a cold air mass, mostly clear skies and light winds will set the stage for widespread frost Friday night into Saturday morning. A hard freeze will bring the end of the growing season from North Dakota across most of Minnesota and well into Wisconsin.

Freeze warnings for temperatures expected to drop to 32 degrees or colder have been posted for northern and central Minnesota, and even as far south as the Rochester area. Frost advisories for frosty temperatures just above freezing, but still cold enough to form frost, are out for south central Minnesota and the southeastern corner of the state.

You can see that the entire Twin Cities area is included in the freeze warning. While a freeze is likely in the area, especially outside the I-495/694 loop, the cores of Minneapolis and St. Paul might struggle to cool to the freezing point due to the usual urban heat island effect, but frost is likely so protect any plants you want to save.

Chilly Weekend

Expect the weekend to be a bit on the chilly side as we wind down the month of September. High temperatures should be mainly from the mid 40s to mid 50s both days.

A few isolated showers are possible on Saturday. Sunday should present a little better chance of showers, but most of us will stay dry. My rain gauge has measured seven inches of rain so far this month, so I am all for staying dry.

Thunderstorms to begin October?

Forecast models are painting a picture of a good chance of thunderstorms to get October underway on Monday. Then more showers and storms could pop up at times through about Wednesday.

Complicating the forecast for next week is category 4 Hurricane Rosa with maximum sustained winds of 145 mph churning in the eastern Pacific. Rosa is forecast to turn toward the north and then northeast and bring heavy rain to the US Southwest. A persistent plume of moisture could arrive in our area toward midweek and enhance our rainfall.

Looking a week out

The first week of October could end with a chilly, damp period getting underway. The 8 - 14 day temperature outlook for Oct. 5 to Oct. 11 is calling for widespread colder-than-normal temperatures.

That could become a wet and possibly snowy period with above-average precipitation as well.