ITHACA, N.Y. — It’s a warm start to 2023, but keep the thicker coats and snow hats handy, because a cold front Wednesday will send temperatures back down to more seasonable values. While some rain is expected Tuesday and Wednesday, no major weather disruptions are anticipated this week.

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Following the storm system that passed through last night, a smaller, weaker disturbance is crossing eastward across the Western Great Lakes and Canada. This system’s size, lack of strength, and passage to the north of Ithaca should keep local impacts to a minimum, with the biggest effects being the ample cloud cover and some scattered patches of drizzle across Upstate New York.

The predominant flow remains from the southwest thanks to an expansive area of high pressure over the Southeastern U.S. As a result, temperatures will continue to be above normal for the next few days, though a storm system developing in the less of the Colorado Rockies will bring the unseasonable warmth to an end later in the week.

For the rest of your Sunday, expect mostly cloudy to overcast skies with highs in the mid 40s. A few patches of drizzle and isolated showers will be possible this evening into the early overnight hours north of Ithaca, but the vast majority of Tompkins County should stay dry, if mostly cloudy. Those clouds will work like a blanket, and alongside weak southerly flow at the surface and stronger flow aloft, temperatures won’t fall back much, descending into the upper 30s to around 40 by Cayuga Lake.

Monday will see invigorated flow from the high to the south, which will advect more mild air into the area, and skies will be sunnier as the weak low heads further east and away from Ithaca. Temperatures will top out near 50 with mostly cloudy skies in the morning and more breaks in the clouds during the afternoon. As the low becomes organized over the Midwest, its warm front will develop and begin to extend towards the Northeast, which will amplify southerly flow Monday night, though a few leading rain showers will begin to move in during the early hours of Tuesday morning. Skies will become overcast again with early lows in the upper 30s climbing into the mid and upper 40s by sunrise Tuesday.

Tuesday will be a very warm day for January, though the strong southerly wind gusts and moderate, steady rain will take the fun out of it. As that warm front swings through Tuesday afternoon, gusty southerly winds 20-30 MPH will be possible through the daylight hours, along with 0.25-0.50″ of rain, primarily falling in the late morning and early afternoon, but maintaining a presence all day long. Highs Tuesday will be in the upper 50s. Tuesday night will be mild but wet, with some scattered light rain showers in the warm sector of the low behind the front, and lighter if still breezy southerly winds. Lows will be in the low 50s.

The storm system weakens Wednesday, but it will slide eastward through the Great Lakes and along the St. Lawrence Valley during the evening. While Tompkins County will enjoy one more warm day, the trailing cold front of the low, with a rather strong high to the northwest, will bring temperatures back down for Thursday. Wednesday will be cloudy with some scattered light rain showers and highs near 60. The front is currently projected to invade around sunset Wednesday, which will bring the showers to a steady end overnight, though it will remain cloudy through dawn Thursday. Temperatures will steadily slide overnight Wednesday as winds turn northwesterly, tumbling from the mid 50s to around 30 by Thursday morning – still above normal, but not nearly so much.

Interestingly, from a technical standpoint temperatures should remain above average through the end of the week. Highs will hardly be above normal, but with ample cloud cover, overnight lows will be 10-15 F above normal. A few snow showers are likely Thursday as a storm system tries to wind itself up on the Atlantic coast, but this is expected to stay away from the Southern Tier as it moves northeastward and runs up against the high pressure system over Canada. Temperatures will be in the mid 30s Thursday with overcast skies. and persistent thick clouds Thursday night will keep temperatures in the upper 20s for lows. New snowfall accumulations will be minimal.

Looking into Friday, there’s a question as to whether snow or rain can make it in from the coastal system, but the latest runs show it as less likely and there’s wiggle room between here and Friday. Right now, with the favored result being that it stays away, that would allow high pressure to build in from the southwest. Skies would be mostly cloudy in this outcome, with highs in the mid 30s. Friday night would be mostly cloudy with lows in the ballpark of the mid 20s.

The weekend shows a Canadian high becoming the dominant lobe of the high pressure air mass, with a weak low over the Midwest that will try to pass through next Monday. Expect a dry weekend with partly to mostly cloudy skies and temperatures a notch above normal, with highs in the upper 30s Saturday to around 40 Sunday, and lows in the mid and upper 20s.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking into the second week of January, the large scale pattern favors a broad ridge with the maximum amplitude over the Great Lakes. This will encourage continued above normal temperatures into the middle of the month. Most of the country would see above normal precipitation as moisture from the Pacific Ocean, the Gulf of Mexico, and the Atlantic Ocean are carried by southerly flow into the continental U.S. On the tail end of the Atlantic leg of that moisture flow, precipitation in Tompkins County is expected to be near to a little above normal.

Brian Crandall

Brian Crandall reports on housing and development for the Ithaca Voice. He can be reached at bcrandall@ithacavoice.com.