ITHACA, N.Y. — Mother Nature’s putting on her finest for all the visitors that will be coming into Ithaca for Cornell Graduation Weekend. While it may be misleading tourists and giving out pairs of rose-tinted glasses to Big Red seniors, there’s nothing that prevents the rest of us from enjoying these fine conditions as well. Other than some minor rain risks Wednesday and Wednesday night, dry, mostly sunny weather is expected this week, with highs near to a little about average, upper 60s to upper 70s.

Your Weekly Weather

Low pressure that moved up the St. Lawrence River valley Saturday brought a welcome if modest amount of rain to Tompkins County Saturday, and behind it a large high pressure system has moved into the region. This expansive high extends from the Deep South to the polar latitudes, with its core gradually moving southeast across Canada towards the Northeastern U.S. This high will provide for extended stable, seasonable weather until the arrival of a frontal boundary later Wednesday.

For the rest of your Sunday, expect clouds to largely clear out for the remainder of the afternoon and evening, with generously sunny skies and highs in the mid 70s. Sunday night will see mostly clear skies to start, with perhaps a few more clouds toward morning as weak pulse of instability moves south of Ithaca. Lows will be in the upper 40s.

Monday will be another dry and pleasant day to be outdoors. Skies will be mostly sunny with highs in the lower 70s. Monday night will be mostly clear with lows in the mid to upper 40s.

By Tuesday, the high will be centered over Atlantic Canada, and this will advect a southerly component into its clockwise flow. Skies will be mostly sunny with highs in the upper 70s and humidity comfortably in the low to mid 50s. Tuesday night will host mostly clear skies, and that southerly warm air advection will result in a milder night, in the mid 50s for lows.

The frontal boundary should drop from the north Wednesday afternoon and evening, as its parent low slides southward across Atlantic Canada, with winds turning from the south to the northwest by evening. This will not be a washout, as the air is still relatively dry and the instability will not be strong. Skies will be partly to mostly cloudy with scattered showers and a few thunderstorms. Highs Wednesday will be near 80, but dropping fairly quickly with the turning of the winds to about 60 by sunset. Wednesday night will see showers end as the front moves to the south, with lows in the lower 40s.

Another strong high pressure system builds in from the northwest for Thursday, though the initial slug of cool northerly air in the high’s clockwise flow will result in a cooler daytime high. It will be mostly sunny with highs a touch below normal, in the upper 60s. Thursday night will see mostly clear skies with lows in the mid 40s.

As the high moves closer Friday, the flow of northerly air will subside and temperatures will perk back up, with mostly sunny skies and highs in the lower 70s. Friday night will see partly cloudy skies and lows in the mid 40s.

Looking into next weekend, when the area will be mobbed with tourists (and I will be nearly 3,000 miles away on the West Coast), there are a couple meteorological flies in the ointment. The latest models have been more productive with an upper-level low working in from the northwest as it slowly heads from Canada to New England. While we’re still expecting generally quiet conditions Saturday with partly sunny skies and highs in the mid 70s, the enhanced instability aloft could trigger a few late-day rain showers. Saturday night will be partly cloudy with lows in the upper 40s.

Sunday will see partly cloudy skies to start, with instability-driven afternoon rain showers again possible. The models have a 20 degree temperature range depending on how close the core of the cold pool aloft is to Ithaca (low 50s in the European, upper 50s in the American, upper 60s in the Canadian), so I’m reluctant to throw even probabilistic temperature ranges out there – it’d be “low confidence” in forecast parlance. Not helpful, I know. It’s a week out, and plenty can change between now and then.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

For the start of June, the large-scale pattern favors a a broad ridge across much of the continental United States. This will result in warmer-than-normal air in place over much of the northern continental U.S. While this will bring Pacific moisture into the Western U.S., here in the east it’ll bring in dry continental air that will result in somewhat drier-than-normal conditions as we head into climatological summer.

Brian Crandall

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