The weather across the eastern Great Lakes will be fairly quiet through Saturday as high pressure builds across the region. There will be a few snow showers today, especially across western New York before warmer temperatures aloft squelch the remaining activity.
The high will slide to the eastern seaboard Saturday morning with a broad southwesterly flow developing across the region. This flow will transport milder air across into the eastern Great Lakes on Saturday. This warm-up will be brief.
A strong trough is forecast to dig southward across the Great Lakes and northeastern United States during the second have of the weekend, then remain in place through the beginning of next week. This trough will allow the coldest air so far this season to settle southward across the region. The trough will be reinforced by several clipper-type disturbances that will track southeastward across the Great Lakes during the first half of next week.
Looking at the details; The primary arctic cold front will cross the area Saturday night. This front will be accompanied by gusty winds and widespread snow showers. Much colder air will spill southward across the area with lake effect snows developing downwind of the wide-open lakes by Sunday morning.
Reinforcing shots of colder air will move across the region Sunday night and Monday keeping the lake effect snows going. While widespread heavy accumulations are not expected, localized heavy amounts are possible in areas where heavier snow bands set up. In particular, snow bands that have connections to the upper lakes could prove to be heavy snow producers.
Areas that will have to be monitored include northern Ohio, where snow bands could have connections to lakes Michigan and Superior, as well as northwestern Pennsylvania and far southwestern New York where snow bands could have connections to lakes Superior and Huron.
There is some question regarding the amount of moisture that will be available in the fresh arctic air mass, but the lakes are unfrozen, and snow/water ratios will be high allowing the snow to add up quickly.
It will remain breezy through early next week as well with very low wind chills possible.
Models show the cold air and lake effect snow showers persisting through the middle of next week. Many locations will not rise above the teens for highs Monday through Wednesday.