ITHACA, N.Y. — A welcome rain will lead off this week’s weather, part of a cold front sweeping across Upstate New York, and likely to stall just far enough away to keep the cloudy skies brief. Warm, tranquil conditions are expected for the second half of the week as we start our trip through meteorological fall.

Your Weekly Weather

A cold front associated with a low pressure system over Atlantic Canada is slowly approaching New York State in a SW-NE orientation (technically called “positively tilted”, for you weather geeks out there). The cooler air mass is just starting to work into Northern New York and the northwest corner of Western New York, and with the cloud cover, it’s creating some large temperature gradients. For example, as I’m writing this, Plattsburgh, up by Lake Champlain, is currently in the mid 50s, while Saratoga Springs, only about 2 hours’ drive to the south, is around 80.

This frontal boundary is moving very slowly. Although it’s near Buffalo at this time, today will remain warm through the daylight hours, humid with highs in the low 80s. However, the rain ahead of the front will begin to move in by late afternoon. From now until about 2 PM, expect mostly cloudy skies with a few scattered showers, particularly west and south of Ithaca where a pre-frontal batch of showers and storms has developed over the Northern Tier. The afternoon and evening will host scattered showers and thunderstorms with near-overcast skies, although rainfall amounts look to stay under 0.1″ prior to sunset.

Heading into Sunday night, it’ll be stormy as the front inches south and east of Ithaca. Expect periods of showers and thunderstorms, with cloudy skies. Lows will be in the mid 60s. New rainfall amounts will be between 0.1″ and 0.25″.

As the front stalls out just south of Ithaca Monday, it’ll be a cooler, grey and rainy day. Highs will be in the lower 70s with periods of light to moderate rain and a few thunderstorms. The most sustained periods of rain being in the mid and late morning hours. Rainfall amounts will be between 0.25″ and 0.50″, although locally higher amounts are possible. If you’re going into the Catskills or are on your way to New York City, be advised that rainfall amounts will likely be 2-3″ in that part of the state, and weakened trees with recent wildfires have increased the risk of falling rocks and mudslides, so be careful on the hillsides and highways. Monday night will see decreasing scattered showers with cloudy skies and lows around 60.

The front will have been shunted just far enough south Tuesday that Tompkins County will be largely dry, although a few stray scattered showers on the rain mass’s northern fringe may skirt the area throughout the day. Skies will be mostly cloudy with highs in the mid 70s. Tuesday night will see dry conditions settle in as high pressure eases in from Canada. Partly cloudy conditions are forecast with lows in the upper 50s.

As that high pressure settles in, the remainder of the week will be dry and comfortable; the general trend is for warmer temperatures towards the weekend as the high shuffles southeastward and southerly winds work into Tompkins County. Wednesday will host partly cloudy skies with highs in the upper 70s. Wednesday night will be partly cloudy with lows in the upper 50s, mid 50s for the hilltops.

Thursday will be very similar weather-wise, slightly warmer with that high’s southward movement. Winds will shift from southeasterly to more southwesterly, which will allow for slightly warmer and drier air. It will be mostly sunny with highs in the low 80s. Thursday night will see mostly clear skies with highs in the upper 50s for Ithaca and the lakeshore, mid 50s elsewhere.

Friday will be a little warmer still, but otherwise another dry, tranquil day. It will be mostly sunny with highs in the mid 80s. Friday night will be mostly clear with lows around 60.

Looking into next weekend, Saturday will be dry with partly cloudy skies and highs in the low 80s, and Saturday night will be partly cloudy with lows in the upper 50s. There are indications a storm system will approach Sunday, with rain moving in by late morning, but it’s a little early to put out specifics. Plan for an unsettled day with periods of rain, cloudy skies, and highs in the mid 70s.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking into the middle of the month, the large-scale pattern favors a pronounced ridge in the jet stream over the eastern two-thirds of the country, with a trough upstream towards the West Coast. Some enhanced Gulf of Mexico flow will result in cloudier and less warm conditions in the Deep South, but up here in the Northeast, marginally drier-than-normal conditions are expected in tandem with the above-normal temperatures.

Brian Crandall

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