ITHACA, N.Y. — It’s been rather hot and uncomfortably rainless lately, so this week offers something of a reprieve. A cutoff low off the New England coast will usher cooler air and showers around its counterclockwise circulation, though the system should move in time for warmer and sunnier conditions to return for next weekend.

Your Weekly Weather

There are a couple of meteorological impacts that are being monitored as the Ithaca Festival wraps up this quiet Sunday. The first is the large cutoff upper-level low parked off the New England coast. Being “cut off” from the jet stream means it will move only very slowly over the next few days, practically parked over Nova Scotia before finally being weakening and being dragged off into the Atlantic. The low’s counterclockwise flow will generate cool N-NE flow over Tompkins County, and temperatures will be several degrees below normal, though being June, that means it should still be fairly pleasant. The low will also destabilize the atmosphere around it and tap oceanic moisture, so showers will be an ever-present concern over much of the week.

The other concern over the coming days are the Canadian wildfires. A few weeks ago it was smoke aloft from Alberta, last week it was the destructive blaze (now fully contained) in Nova Scotia, and now continued warm, dry conditions have caused widespread fires to erupt across the remote forests of Quebec – the provincial authorities have straight up said they can’t tackle them all. Northerly winds will waft smoke into Upstate New York, and air quality may worsen as a result. It’s also worth noting that New York State is under high fire risk statewide at the moment. We need rain, more than the week ahead is likely to provide.

At this time, the smoke is primarily over Western New York well above ground level, and cloud cover is persistent over the eastern half of the state. But in the Finger Lakes, things are sunny and clear for the time being. A few clouds may build in towards sunset, but abundant sunshine should continue, with a northerly breeze and highs topping out in the low 70s, a touch below normal. Tonight will see winds slacken and clouds build in towards morning as the coastal low strengthens, with lows in the upper 40s in urban Ithaca and along Cayuga Lake, and mid 40s in the outlying areas.

The stronger low will be better able to advect moisture and is likely to retrograde (move westward) a little bit on Monday, which should be enough to introduce the threat of rain showers late in the day, especially east of Ithaca. Skies will be mostly sunny to start, become somewhat cloudier during the PM hours, and temperatures will top out in the mid 70s. Expect some light scattered rain showers Monday night, maybe even a weak thunderstorm or two, with generally light rainfall amounts. Skies will be partly cloudy with lows around 50.

Heading into Tuesday, enough moisture and instability will be present that some on-and-off showers and afternoon thunderstorms will be possible during the daylight hours – right now, instability forecast models of the atmospheric column suggest a few of these may develop heavy rain and small hail, but there’s not enough energy to produce truly severe weather. Highs will be in the low 70s with partly cloudy skies. Tuesday night will see the showers and storms taper off in the evening, leaving mostly cloudy skies for the rest of the night, and lows settling into the upper 40s.

Wednesday sees the low stay in place over Nova Scotia, though less moisture and moisture-enhanced instability will remove the risk of thunderstorms. Some scattered showers will persist, however, especially north and east of Ithaca, with partly cloudy skies and highs in the low 70s. Wednesday night will be dry with mostly cloudy skies and lows in the upper 40s.

The low begins to drift away to the ENE Thursday morning, though Ithaca/Tompkins will be in store for one final day of cool, unsettled conditions. It will be partly to mostly cloudy with some scattered showers, maybe an isolated thunderstorm driven by daytime heating, and highs around 70. Thursday night sees the showers end with mostly cloudy skies and lows in the upper 40s once again.

High pressure builds in from the Western Great Lakes for Friday. Winds will turn from the N-NW to the WNW, which will allow sunny skies and highs in the mid 70s, a picture perfect June day. Friday night will see partly cloudy skies and lows around 50.

Looking into next weekend, the high moves southeastward, resulting in a mostly sunny day for next Saturday with highs around 80. Saturday night is likely to see increasing clouds as models suggest a cold front approaches as part of a compact Canadian low, with lows in the mid 50s, and Sunday will see showers, primarily in the morning, with mostly cloudy skies and highs in the upper 70s.

Images courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Mid-June is likely to be on the cooler side. Large-scale medium-range models show a bubble of warm, dry continental air over South Texas and the Gulf of Mexico, and a high pressure ridge over the Northwest and Upper Midwest. However, downstream over the Northeast, cooler air is likely to pour in from Canada. Near-normal precipitation is expected over the period.

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