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Happy winter solstice; travel weather and update on Wednesday snowstorm potential

The sun angle is at it's lowest Friday in the northern hemisphere. The winter solstice, also know as the astronomical beginning of winter, occurs at 4:23 p.m. CST  in the Twin Cities metro area.

The winter solstice is sometimes referred to as the December solstice, as described by the website timeanddate.com:

The Sun is directly overhead of the Tropic of Capricorn in the Southern Hemisphere during the December Solstice.

The December Solstice occurs when the Sun reaches its most southerly declination of -23.4 degrees. In other words, when the North Pole is tilted furthest away from the Sun.

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Image credit: timeanddate.com

Happy astronomical winter! Meteorological winter began on Dec. 1.

Of course, some people might argue that our winter began in November this year, with all those chilly temps and clouds!

Temperature trends

Our average Twin Cities metro area high temp is 25 degrees this time of year.

We'll be a bit warmer than that over the next few days.

Our Friday highs should reach the lower 30s in most of the southern half of Minnesota, with 20s to the north.

Saturday highs will be similar, with 20s north and 30s south:

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Some spots in the southwest will see upper 30s on Saturday.

Central and northern Minnesota will top out in the 20s on Sunday, with 30s south:

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Twin Cities metro area highs are expected to be somewhere right around 30 Monday through Wednesday of next week.

Snow chances

Travel weather looks generally good this weekend, but some areas will see snow at times.

Periods of light snow are possible in northwestern and north-central Minnesota Friday evening. The northern half of Minnesota will have the best chance for periods of light snow overnight Friday night and on Saturday. The Twin Cities metro area could see a Saturday flurry.

Much of northern Minnesota will have a chance of light snow Saturday night and Sunday.

The National Oceanic and Atmospheric Administration’s North American Mesoscale forecast model shows the potential snow pattern from late Friday evening through Sunday afternoon:

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NOAA NAM simulated radar from Friday evening through Sunday afternoon, via tropicaltidbits

The color chart to the right of the loop refers to the strength of the signal that returns to the radar, not to the amount of snow.

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

Christmas Eve looks quiet, then southern and central Minnesota could see some light snow showers Christmas morning.

Wednesday/Thursday snowstorm potential

The Twin Cities office of the National Weather Service created a nice graphic to illustrate the potential tracks of the late Wednesday/Thursday winter storm:

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NWS Twin Cities

Track B would give Minnesota the most snow, along with high winds and very difficult travel late Wednesday through Thursday.

The impulse that's expected to develop Wednesday's low pressure system is still over the Pacific ocean, and models will tend to merge into a smaller range of storm tracks in a few days.

The National Oceanic and Atmospheric Administration’s Global Forecast System model shows this potential precipitation pattern Wednesday afternoon through Friday morning:

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NOAA GFS precipitation rate (mm/hour) Wednesday afternoon through Friday morning, via tropicaltidbits

That's quite a southward shift of the heavy snow pattern since yesterday's GFS run, so we'll see if that model shifts north again.

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.

It's interesting that NOAA's experimental FV3-GFS model still shows a more northerly track of the low pressure system, and heavy snow for parts of Minnesota:

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NOAA FV3-GFS precipitation rate (mm/hour) Wednesday afternoon through Thursday night, via tropicaltidbits

The FV3-GFS is expected to be operational sometime in 2019, and will replace the current version of the GFS model.

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Late morning update

The new run of NOAA's GFS model has shifted the storm track northward, which moves the heavy snow back up over parts of Minnesota. Here's the GFS potential precipitation pattern Wednesday afternoon through Friday morning:

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NOAA GFS precipitation rate (mm/hour) Wednesday afternoon through Friday morning, via tropicaltidbits

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Check for updates on this potential winter storm, especially if you have travel plans for next Wednesday and Thursday!

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.