The upcoming midweek storm is one of several systems that promises to bring precipitation and eventually the month’s coldest weather will descend on the region.
As we mentioned previously, the upper part of the stratospheric polar vortex will get disrupted and likely bleed down to the troposphere where our weather occurs.
The bottom line is cold spells will last longer during mid-February, but we will still have a few very warm days this month! The devil is in the details below.
The vortex will split, with part of the vortex moving towards the Hudson Bay around February 12. The current Alaska Ridge pattern will be responsible for bringing in colder temperatures next week. The pattern most closely associated with a disruption of the Polar Vortex is the Greenland High, which shifts the storm track to our south, increasing the odds of snow (as seen below). The Greenland High will return around Valentine’s Day.
The pattern that best matches this month is February of 1986. The Greenland High and Alaska Ridge dominated the pattern as seen below.
Our closest-matched analog shows our snowiest period was February 10 to 15, with the snow depth reaching 10 inches by February 15. February 13 was the coldest morning of the month with a low temperature of 5-degrees above zero degrees. Then, we rebounded into the mid-60s on February 20 before colder temperatures returned February 22-28. Another 4 inches of snowfall accumulated during the final few days of the month.
Two out of three of our February analogs produced above average snowfall (9″) across our region and the vast majority of the Midwest into the Northeast.
Our temperatures will likely average out to about 32 degrees by February 28, which is one degree shy of our February average of 33.1 degrees. The map below shows the temperature departure from average of the top three analog February’s that closely match the trends we expect this month.