ITHACA, N.Y. — It seems this year’s fashionable summer attire includes flowy sundresses, tropical button-downs, and N95 masks. Warm to hot and humid conditions are expecting in the unsettled week ahead, but the biggest concern at this time will be the incoming plume of Western Canadian wildfire smoke that will plow across Tompkins County tonight through Monday and Tuesday. Air Quality Health Advisories have been posted.

Your Weekly Weather

A cold front associated with a Canadian low pressure storm system has swept across the region this weekend, with a reinforcing front likely to sweep in from the northwest on Monday. While a break from the heat and humidity would be welcome, the surface winds will be from the southwest where air is warmer. It is also where the air is smokier, as a large plume of polluted smoke-filled air has barreled southeast from Western Canada into the Midwest, plaguing much of the Ohio River Valley and Western Great Lakes this past weekend. Normally smoke from Western Canada thins out and up as it blows downstream, but there’s simply so much forest burning that it’s dispersing and still capable of producing unhealthy to hazardous air pollution levels across the Northern U.S.

That expansive plume of particulate-laden air will be forging ahead across Upstate New York tonight and tomorrow, before beginning to lift northeastward with the parent low of the reinforcing front later Monday into Tuesday. As I write this, the first tendrils are already working into the Buffalo area.

We’ll be doing a separate article to focus more explicitly on the smoky situation and the public health/safety response per state and local agencies, but the air will be at Unhealthy AQI levels for the general population for the 24-hour period from midnight tonight to midnight Monday night, and likely extending well into Tuesday (Air Quality Alerts are posted no earlier than one day in advance).

What that means is, if you’re a generally healthy person, it’s fine to go outside for shorter periods, but outdoor exercise, strenuous or extended hours-long outside activities are best left for another day. The elderly, infants and those with pre-existing cardiovascular and respiratory conditions would be better off staying indoors tomorrow with windows closed – if you want to use air conditioning, keep in mind that central air and wall units (PTACs) usually have robust filters, but window unit filters cannot effectively clean polluted air. If you only have a window unit or no A/C, you’re better off recirculating indoor air with a box fan. If you’re a “Sensitive Group” as described above and need to be outside, consider wearing an N95 mask, which should filter out some of the smoke (not all).

As always, you can check the latest smoke observations on the EPA Fire and Smoke map here. Note that particulate/smoke air quality standards are issued for 24-hour averages; the AQI can be worse for shorter stints within that 24-hour period.

Turning back to the weather, expect muggy conditions to continue with those winds turning southwest, and temperatures falling back from the low 80s into the 70s over the next few hours. Skies are clearing, in a sense, but the smoke working in will quickly create a hazy, milky atmosphere aloft. Tonight will see increasing smoky haze with mostly clear skies otherwise and lows in the mid 60s.

Monday will be a smoky, hazy days, and that tends to reduce high temperatures due to increased reflectivity of incoming sunlight. While highs are forecast to be in the mid to upper 80s, given the smoke, it might end up a little cooler. The unstable conditions will allow for increased clouds later in the day with some pop-up showers and thunderstorms in the evening; unfortunately, fine smoke particles are pushed around by rain, but very little gets washed out. Monday night will see scattered showers and thunderstorms as the reinforcing front approaches, with perhaps 0.1-0.25″ of new rainfall, partly to mostly cloudy skies, continued haze, and lows in the mid 60s.

Tuesday should see some improvement in the air quality, though it will likely be later in the day when that happens, and Air Quality Advisories are likely. It will be mostly cloudy with scattered showers and thunderstorms as the front pushes through, with mostly cloudy, hazy skies and highs in the low 80s. Tuesday night will see partly cloudy skies and lows in the low 60s. Long-range smoke models are optimistic that most of the smoke will clear out by late Tuesday night, so keep your fingers crossed.

Wednesday sees a bubble of high pressure move in from the Western Great Lakes. It’ll be a marginally less humid day than what we’ve seen lately, and rather pleasant with mostly sunny skies and highs in the low 80s. Wednesday night will host partly cloudy skies and lows around 60.

That high moves eastward for Thursday and another low pressure storm system approaches from the Upper Midwest and across the Great Lakes. It will be warmer and muggier again, with some afternoon showers and thunderstorms as more unstable air takes hold ahead of the storm system. Highs will be in the mid to upper 80s with partly cloudy skies. Thursday night will see scattered showers and thunderstorms, mostly cloudy skies, and lows in the mid 60s.

The storm system’s core slowly moves across Southern Ontario Friday, and it will be a stormy day. Expect a mix of showers and thunderstorms with mostly cloudy skies and highs in the low 80s. Friday night will see periods of rain and thunderstorms with lows in the low 60s.

Right now, next weekend doesn’t look too bad, as more stable air builds in behind the low. A few lingering showers are possible early Saturday, but the second half of the day and Sunday both look to be drier. Highs will be in the upper 70s Saturday and low 80s Sunday, with lows around 60.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking into the end of July, the large-scale meteorological setup calls for a large jet stream ridge in the Western United States, and a troughier, stormier setup downstream over the Eastern U.S., possible a cutoff low. Tompkins County will be near to slightly above normal in temperature for the period, with slightly above normal precipitation expected. What this setup typically means is a more humid pattern with cooler highers and lower lows. Meanwhile, places in the south and west struggling with intense, dangerous heat are likely to see little reprieve through the remainder of this month.

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