High pressure will be in control of the Finger Lakes Monday and Tuesday with sunny skies.
This sprawling high pressure system will result in some chilly air on Monday due to north winds on the front side of the system. High temperatures today should range from the upper 20s to low 30s, with the warmest locations across the Southern Tier and colder air to the north. This is actually opposite of the normal temperature distribution for our region.
Clear to partly cloudy skies will dominate the sky today and into tonight. Temperatures will drop quickly this evening, but areas that held onto a snow pack this weekend will drop the furthest.
Generally, the northern and western Finger Lakes have the most snow on the ground and will drop into the single digits and teens. Further south and east, where little to no snow remains, lows will be in the teens and even 20s.
Tuesday should start out sunny, but clouds will increase during the afternoon. With high pressure now to the east, the return flow on the backside will be from the south, pushing temperatures into the upper 30s and low 40s.
No precipitation is expected until after midnight Tuesday, when some rain showers will start to push in. A little sleet or freezing rain may fall near and east of I-81 before that, too, quickly changes to rain.
Rain will becomes steadier and more widespread Wednesday morning as a strong storm system barrels up the west side of the Appalachian Mountains. Period of heavy rain will be possible Wednesday afternoon and evening.
In fact, there is a decent chance for a few rumbles of thunder Wednesday afternoon and evening. It is not unreasonable to think a couple of severe thunderstorms warnings may be needed somewhere in the general central NY/northeastern PA region should a line of heavier rain, strong winds and occasional thunder develop.
Such a line actually developed with last week’s winter storm with some locally damaging winds between Philadelphia and New York City. Numerous severe thunderstorm warnings were issued. Such a scenario is not unheard of in the Finger Lakes, though it is uncommon.
Strong winds will develop Wednesday night, regardless of any thunder. The strongest winds will likely be towards the eastern Finger Lakes, but the extent and strength of the wind is still a bit uncertain. At a minimum, gusts of 30-40 mph seem likely, but stronger winds may be possible.
The warm dry slot of the storm will cut off precipitation early Thursday. Temperatures should rise into the 40s for all of the Finger Lakes, but the eastern regions could push well into the 50s Thursday morning.
Colder air and precipitation will quickly move back in Thursday afternoon as the storm pushes into eastern Canada. Rain will mix with, then turn back to snow by Thursday evening. A couple inches may fall before quieter weather settles in for Friday.