Accumulating Snow on the way Thursday into Friday

(5:37 PM CT, Tuesday, January 12, 2021)

Here’s the latest on the late week system which will impact northeast Minnesota and northwest Wisconsin.

  • Computer models continue to show some differences on the storm track. Using an ensemble approach shows the Euro camp (EPS model) still digging the low further south compared to the GEFS model which has the low on a more northerly track.
  • If the low takes a more northerly track (similar to the GEFS) then northwest Wisconsin and the Arrowhead of Minnesota would get the most snow, with lesser amounts of snow for north-central Minnesota say from Brainerd north to International Falls.
  • A more southerly track to the low (similar to the Euro) would increase the chances for a significant snow event in most of the Northland, with the highest totals occurring near Lake Superior for both the North Shore and South Shore due to lake enhancement.
  • This system does look fairly warm, however, so the snow that falls could end up being the wet/slushy kind and not the fluff or powder. It’s even possible we could see the snow change over to a mix at times especially near Lake Superior as surface temps hover close to the freezing mark Thursday afternoon and again on Friday.
  • This system could be of long duration, meaning it could snow from Thursday morning all the way through Friday night, but snowfall intensities may not be all that heavy during the majority of the time that it’s snowing, but with the long duration of snow, expect to see a few to several inches of accumulation in our area.
  • Timing of this system continues to favor Thursday morning into Friday evening with precipitation starting in western areas of the Northland early Thursday morning, then spreading farther east-northeast by Thursday afternoon the way it looks now.

Mid/upper level low/trough digs S-SE (dark black lines on map) across the Northern Plains on Thursday, then this system stalls out once it reaches southern Wisconsin on Friday before it exits to the NE early Saturday.

Meanwhile milder air (red lines on map) could push west-northwest into parts of the Northland Friday which could lead to not only wet snow, but also a mixture of precipitation types since surface temps could be awfully close to the freezing mark even though temps aloft remain sufficiently cold enough to produce snow.

Here’s the 500mb forecast per 18z RGEM model valid 6 AM Thursday thru Midnight Saturday.

Source: https://www.tropicaltidbits.com/

…Here’s my preliminary snowfall forecast for Thursday through Friday night…

-Highest amounts in parts of northwest Wisconsin (South Shore area) where totals could exceed 8″.

-A range of 2 to 6 inches of snow for the rest of the Northland, but totals could exceed 6″ along the North Shore of Lake Superior if lake enhancement occurs Thursday night into Friday.

Note: Snow to liquid ratios don’t look overly impressive with this system due to the milder temps (wetter snowfall) but SLR’s of around 10:1 or possibly a little better are possible during this event.

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Widespread high wind warnings and watches in effect across the Northern Rockies and Northern Plains Wednesday and Thursday, while farther east we could see some winter weather alerts (yellow outlined area on map) issued by the NWS sometime on Wednesday for the Thursday-Friday time frame.

Note: It is interesting how weather patterns tend to repeat themselves. For example, Duluth saw a very dry first half of December which was followed by a snowier second half of December which began on December 12th, and from that point on we picked up 16.5″ of snow in Duluth. Here we are a month later and the weather pattern has been very similar to what we had back in December. Very little precipitation in the first half of January thru the 12th, but let’s just include the 13th as well since we won’t be getting any precipitation in Duluth on Wednesday, but now it looks like the pattern will be turning a little wetter/snowier for the second half of January, although this time around it’ll be starting on January 14th, so just 2 days later than what we saw back in December where the more active pattern started on the 12th.

Tim

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