Warm up begins, but watch its end Friday night

Temperatures on the Rise

The next three days in the Finger Lakes will be marked by above normal temperatures as a surge of warm air moves north. However, significant winter weather may be in store for the region as temperatures crash Friday night.

First things first — the warm up.

Temperatures are varied across the Finger Lakes early Wednesday morning thanks to some lake effect cloud cover that has been very stubborn but is finally pulling out.

From Seneca Lake eastward, temperatures are mostly in the low and mid 20s as the cloud cover overnight prevented temperatures from falling.

Further west, temperatures range through the teens where skies were mostly clear overnight.

High pressure has set up to the east of the region, placing the Finger Lakes in the southerly return flow on its backside.

Warm air is moving in both at the surface and aloft from the southwest and will push temperatures into the 40s for the western Finger Lakes today, with highs near 40 for most other places.

A few rain showers will accompany the warm air this evening with temperatures only dropping a degree or two overnight.

Thursday will have temperatures near 50 degrees for most areas with a few mid and upper 40s lingering in the far eastern Finger Lakes and some low and mid 50s in the Rochester area.

Storm System #1 Friday

A small area of low pressure will pass across southern Canada Thursday night into Friday.

South winds ahead of this and behind a large high pressure system over the Atlantic will set up a stream of very moist air across the Mid-Atlantic and into Upstate New York.

Rain should break out after midnight Thursday and persist into Friday morning. Temperatures during this time will remain around 50 degrees.

Some of the rain may come down heavy for a time and even a rumble of thunder cannot be totally ruled out.

Rainfall amounts will range between one-half and three-quarters of an inch, with some localized areas seeing closer to an inch.

The primary concern with flooding will be with ice jams on rivers as waters rise and the ice breaks up. Those who live near ice jam prone rivers and streams should keep an eye on water levels early Friday.

The rain will come to an end Friday morning and the sun may come out briefly. Temperatures will push well into the 50s and a couple places along the I-90 Corridor could even hit 60 degrees.

Storm System #2 Friday Night-Saturday

After the extreme warmth Friday afternoon, a strong cold front will pass through Friday evening.

Temperatures will quickly drop from the 50s into the 30s as the front passes through.

Meanwhile, a second, stronger low will be taking shape over the Appalachians. Originally, this low was supposed to pass into the Great Lakes, keeping us on the warm side of the system.

However, a path across Pennsylvania and into New England is now expected, putting our region on the cold side of the storm.

There are two concerns with this system. First is a period of freezing rain which could result in significant ice accumulations. Second would be a period of heavy snow. A mix of the two is possible, as is a mostly ice or mostly snow event.

Areas further west will have more of a chance for snow while areas further east could see more ice.

However, the uncertainty remains very high with this system! The storm track has not been consistent and a slight variation in its path would have major implications for our forecast.

While significant winter weather is possible, it is not yet a certainty. A warmer path further west, or less precipitation with a storm further south and east are also still possible.

Please continue to monitor the forecast closely and beware of specific details this far out. The forecast will need to be updated many more times before this system arrives.