Significant Weather Blog: Wednesday, January 21, 2026 4 PM

Very Large Winter Storm Will Impact Most of the Eastern United States This Weekend and Probably Including Southern New England Late in the Weekend

There is a lot to discuss with regard to upcoming weather.  This blog is focused on southern New England but will note a little about how the weekend storm looks to cover an exceptionally large part of the country.  Before diving into the storm potential, will take a quick look at a minor event tonight and the exceptionally cold temperatures expected this weekend.

Minor Snowfall Tonight into Early Thursday

A light precipitation event in association with a passing short wave upper trough will affect southern New England tonight.  Occasional light snow will spread west to east late this evening and end by daybreak.  Over most of interior southern New England northwest of the Boston to Providence corridor, a half to an inch of snow is likely tonight.  Isolated 1 to 2 inch amounts may occur over the Worcester Hills and Berkshires.  A few spotty light rain or mixed rain and snow showers may occur across southern RI and southeast MA.  Impact should be minimal with perhaps a few slippery spots on interior secondary roads for the first part of the Thursday morning commute.

Extraordinary Cold Temperatures this Weekend

A piece of the polar vortex will break off and traverse Ontario and southern Quebec this weekend and unleash an arctic air mass into our region.  Temperatures will plummet to near or a little below zero Friday night.  Temperatures will struggle to go above 10 degrees Saturday.  Combined with strong northwest wind gusts, wind chills of 10 to 20 below zero are expected across higher terrain and 5 to 15 below zero elsewhere.  Cold temperatures will persist into at least early next week.

Large Winter Storm Will Impact Much of the Eastern United States this Weekend

A surface low pressure system will develop along a boundary between arctic air to the north and tropical moist air to the south.  This looks to be a prescription for a widespread overrunning snow and ice event.  A very large swath of heavy snow may spread from the Texas panhandle through Oklahoma, the mid Mississippi Valley, Ohio Valley, and onward into the mid Atlantic and Northeast states.  This includes the I-95 corridor from Washington, DC to New York City to Boston.  Further south, a devastating ice storm may occur across portions of Texas, Louisiana,  Arkansas, Mississippi, Alabama, Tennessee, Georgia, South Carolina, North Carolina, and Virginia.  The event is still several days away and there are track differences in the various models.  Thus, it’s too soon to be very specific on the areas that will be hardest hit.  This does have the signature of an event, however, that will result in major, widespread travel (ground and air) delays.  The rest of this blog will focus on southern New England.

The suite of global operational models and their ensembles have trended north in the past 24 hours. Although there are some differences in track and intensity, it looks as though all of southern New England could be at risk for a major winter storm.  The event for this part of the country is still several days away and so will likely see changes in model details with future runs.  Given the cold arctic air mass in place, snow to liquid ratios could be quite high (i.e., high fluff factor).  Due to a trailing upper short wave trough in the northern jet stream, a few models depict an elongated surface low (or surface low with an elongated inverted surface trough to the west) with snow persisting well into Monday.  Thus, there is some uncertainty in duration.  Also, due to the arctic air mass, there could be some ocean enhancement to the snowfall in east coastal areas.

At this time, it looks as though snow may spread southwest to northeast across southern New England on Sunday and possibly becoming heavy at times during the afternoon and Sunday night.  Snow at various intensities may linger well into Monday.

It’s too soon to project specific snowfall totals for this event still 4 days away.  Will monitor various model trends and update this message tomorrow (Thursday).

About this Blog and Disclaimer

The National Weather Service monitors the weather 24/7 and updates forecasts, watches, and warnings as necessary.  For most of southern New England, refer to your local Weather Forecast Office for the latest forecast/warning information at weather.gov/box.  For information from other Weather Forecast Offices, go to weather.gov and click on the location of interest on the map.

A blog is issued when there is a potential risk of hazardous weather to southern New England and serves to provide background information regarding the significant weather with somewhat of an educational slant.  In the case of hurricanes, the author will attempt to issue a message when any portion of the United States coastline may be seriously impacted.  It’s intended to complement and not serve as an alternative to official forecasts issued by the National Weather Service.  Readers are urged to check National Weather Service forecasts and warnings for the most timely and updated weather information.  This weather message is solely produced by the listed author and does not constitute an official product of the Blue Hill Observatory and Science Center (BHOSC).

The frequency of this blog will depend upon the nature of the weather threat and availability of the author.  Thus, for the latest information on weather forecasts and warnings, refer to the National Weather Service, which monitors and forecasts the weather 24/7.

Blue Hill Observatory and Science Center (BHOSC)

The BHOSC maintains a continuous daily observation record that dates from February 1, 1885 without interruption and provides educational information on weather and climate to area students and the community at large.  Your support of BHOSC is much appreciated and enables this nonprofit organization to maintain the long-term climate record at the Blue Hill Observatory (longest continuous record in North America) and provide valuable educational resources on weather and climate via outreach to schools, site visits/tours, webinars, and conferences.  For more information on the Blue Hill Observatory and Science Center, explore bluehill.org.

Message issued January 21, 2026 by:
Bob Thompson
Retired National Weather Service Meteorologist
Blue Hill Observatory and Science Center Board member