ITHACA, N.Y. — For those of you wanting a nice, comfortable, cool break from all the summer heat and humidity we’ve been having – well, you’ll be waiting for some time yet. Hazy, hot and humid are the name of the fame this week, with partly cloudy skies and potentially hazardous heat, pop-up storms during the evenings and humid nights. I’m no businessperson, but I’d wager the ice cream and popsicle makers are doing quite well this year.
July was hot. With an average temperature of 72.7°F, temperatures were 3.9°F above normal, the warmest July in Ithaca since 1955, according to the Northeast Regional Climate Center based out of Cornell’s Bradfield Hall. especially notable since those earlier decades had the weather station on the roof deck of the old Roberts Hall on Cornell’s more urbanized campus – in other words, the cooler location of rural Dryden’s Game Farm Road has finally caught up to the urban heat island recorded decades ago. High temperatures were slightly more above normal than the lows (4.2°F vs 3.6°F), which tends to be indicative of a drier heat.
Across the Northeast and Mid-Atlantic, records fell like melted ice cream from a cone. 11 of the 35 first-order weather stations recorded all-time highs for their warmest month of any month on record since recording began, which for most of these stations means 100-150 years of records. Among the all-time hottest are Buffalo (77.6°F), Syracuse (77.1°F), Baltimore, Scranton, Burlington, Vermont, and Portland, Maine. The only station that didn’t record a top ten hottest month was Boston. For comparison’s sake, Buffalo’s average temperature would have been totally average if it were a July in Washington DC. The heat dome reigned supreme, and the Northeast baked.
On the precipitation side, July also happened to be a wet month locally, though as is often the case with the summer months, it depends more on if you were hit with pop-up severe thunderstorms than broad weather events – as the kids say, “YMMV”, your mileage may vary. The Game Farm Road site recorded 4.68″, considerably more than the usual July precipitation total of 3.83″, but the amount appears to have been so localized it barely shows up on the NRCC’s high-resolution precipitation anomaly charts. The southeastern portion of the county (Caroline, Dryden) was above average, while the western edge and northern portion (Lansing, Groton) were below average. Those pop-up storms can deluge one town with rain, and totally miss the next one over.
The high variability was a theme across the Northeast. Newark, New Jersey had its wettest July on record, while Hartford, Connecticut had its fourth-driest. Five stations had July rainfall of 50% normal or less, while six had 150% of normal or more.
Going into this week, the setup will be much the same as July – temperatures will be substantially above normal throughout the week, with convective showers and thunderstorms likely to result in more scattershot rainfall amounts across the map.
Your Weekly Weather
The primary driver of our weather for this week will be a strong and expansive area of high pressure extending from the northern Gulf of Mexico all the way to the Mid-Atlantic. Since high pressure systems have clockwise circulations in the Northern Hemisphere, that means that there’s a substantial southwest wind into the Southern Tier, and that air being advected into the region is hot and humid. With the size of the high and the jet stream displaced poleward, this hot and humid pattern will dominate out weather for much of the week. Also, this moist air will be on the edge of the high, and more unstable, meaning a daily threat of pop-up showers and thunderstorms during the PM hours, and dying down again with the loss of daytime heating.
After topping out in the mid 80s today, for the rest of your Sunday, expect a fairly quiet and humid night ahead, with partly cloudy skies and a low in the upper 60s. A short wave (pulse of instability) is passing to the north, but it is too far north to be of much impact to Tompkins County, except for a few additional clouds. Dewpoints will be in the mid to upper 60s, so if you can close the windows and use AC, this would be a good night for it.
Monday will see the winds turn from the west to the southwest, and the heat and humidity will rise accordingly. Highs will be in the low to mid 90s Monday with a few passing clouds, though enough instability will be present for an isolated thunderstorm or two in the later afternoon and early evening hours. The biggest risk with these storms will be flash flooding, because a lack of steering flow aloft means they will move very slowly when they develop. The humidity is going to be oppressive, with dewpoints the low 70s, and this will make it feel like it’s about 100°F. Exercise caution if you’ll be outside for an extended time period or exerting yourself, keep cool if and when possible, and be mindful of potential heat-related illness. Monday night will be mostly clear, warm and humid, with lows around 70°F.
Tuesday will start off similarly to Monday, as continued southwest flow allows for temperatures to reach into the mid 90s once again, with high humidity and heat indices. Tuesday may prove slightly less awful on the heat and humidity, as clouds build later in the day as a cold front approaches. This front will begin to slow down and stall out to the west during the afternoon, which will limit its ability to trigger squall lines of thunderstorms, but there will be enough instability ahead of the front for a few scattered pop-up showers and storms. With the front slowly pushing through overnight Tuesday into Wednesday morning, this storm threat will persist, so bring an umbrella if you’ll be outdoors Tuesday night. This threat will pass with the frontal passage a little after midnight. Expect mostly cloudy skies for the rest of the night, with lows in the upper 60s.
Wednesday will be a little cooler and a little less humid, but since the front stalls out during the day just to our south in northern Pennsylvania, unable to dislodge the high, there won’t be much in the way of cooler air filtering into the Southern Tier. Highs will be in the mid 80s with partly cloudy skies, and a few pop-up showers and thunderstorms in the late afternoon and early evening hours as the presence of the front continues to destabilize the air aloft. Wednesday night will see the front slowly shuffle southward, which will allow the air to stabilize and some cooler air to slide in. Lows will be in the low to mid 60s with less humidity (still rather humid, though, with dewpoints in the low 60s) and partly cloudy skies.
Thursday will see high pressure move over the Great Lakes, though broadly speaking it functions more as an extended lobe of the Atlantic high that dominated the weather for the start of the week. In this case, that basically means more of the same heat and humidity. Expect partly cloudy skies with convective thunderstorms late in the day, and highs in the mid 80s with humid conditions. Thursday night will see the showers and thunderstorms wind down shortly after sunset, and mostly cloudy skies will prevail with lows in the mid 60s.
Friday will be yet another, hazy, hot and humid day, with partly cloudy skies, more showers and thunderstorms bubbling up in the late afternoon and evening hours, and highs in the mid to upper 80s with generally muggy conditions. Friday night will be mostly cloudy with lows in the mid 60s.
Your weekend is looking to be more of the same. Expect partly cloudy skies both Saturday and Sunday, with shower and thunderstorms blossoming in the 3-6 PM time frame, drying out after sunset, and partly to mostly cloudy skies overnight with lows in the mid 60s.
In sum, it will be warmer than normal, more humid than normal, and it could be wetter than normal if you’re caught under a thunderstorm, but otherwise there’s no sustained period of rainfall in the forecast for this week.
Looking later into August, models suggest a cutoff area of low pressure will park itself over the lower Mississippi River Valley, and being cutoff from the jet stream will allow it to linger for several days. This will result in localized coolness, but the low’s counterclockwise flow will likely funnel humid Gulf of Mexico air into the northeast, meaning warmer and wetter than normal conditions in the Southern Tier are likely. This hot, humid summer isn’t taking any breaks.