ITHACA, N.Y. — The start of the week will be cooking as much as your barbecue as temperatures climb into the 90s for the end of May. However, a mid-week cold front should bring temperatures done to more seasonable values in time for next weekend and the Ithaca Festival. I thought for sure that there was a hex in place to prevent good weather and the festival from happening at the same time, but I digress.

Your Weekly Weather

Warm and pleasantly tranquil conditions are in place thanks to an area of high pressure centered south of Bermuda. Given clockwise flow around highs in the Northern Hemisphere, that means warm southerly air is being advected into the Northeast. Skies are mostly sunny this Sunday, with highs topping out in the low 80s, a tad above average for late May. Thankfully, dewpoints remain on the low side, in the lower 50s, so it still feels comfortable outdoors.

A broad low pressure storm system will strengthen as it moves northeastward over the Great Plains tonight and tomorrow, and that’s going to tighten the pressure gradient with the offshore high. That tightening of the gradient will induce a stronger southerly flow, and result in warmer temperatures for the start of the week. Tonight will be quiet with a few passing clouds and lows in the upper 50s.

As for Monday, with that enhanced flow, expect mostly sunny skies and temperatures to make it into the low 90s. It will be noticeably more humid, rather muggy with afternoon dewpoints in the mid 60s. This will make it feel a little warmer than it actually is (the heat index, which will be a degree or two warmer), but no heat advisories are expected at the moment. Monday night will see mostly clear skies and a rather balmy low in the mid 60s. Some valley locations may experience fog around sunrise Tuesday.

Tuesday will see the surface air flow take in more hot, humid air from the Deep South as the Great Plains storm system lifts into Canada. Oddly enough, this starts to loop around the elongated high so it’s a Southern U.S. air mass carried in on a northwest wind. It’ll be another hot and muggy day with mostly sunny skies, highs in the low to mid 90s, and a dewpoint in the mid 60s. Tuesday night will be partly cloudy with some valley fog once again possible, and lows in the mid 60s.

Wednesday shows the cold front of the low extending from Ontario through the Ohio River Valley and all the way back to Texas. The front should make it through Tompkins County during the afternoon hours, but the induced instability will result in a rather stormy Wednesday from mid-morning through mid-evening. Some of these could be severe, so keep an eye out for alerts if you’ll be outdoors during the day Wednesday. This will be the “pop-up” convective variety of storms, with partly cloudy skies in between and a muggy day with highs in the upper 80s. The last of the showers and storms, kept going by a shortwave pulse of instability closely trailing the front, will end by midnight, and expect clearing as drier, more stable enter comes in on northwest winds, with lows Wednesday night in the upper 50s.

Thursday will be a cooler and much less humid day as a light northwest wind channels in air from the Western Great Lakes and Canada. Another weak shortwave passes to the south, and a few isolated rain showers will be possible, but most communities will stay dry with partly cloudy skies and highs in the upper 70s. Thursday night will see the showers wither away by midnight with partly cloudy skies and lows in the low 50s.

Friday shows some uncertainties as a weak trough traverses the Northeast. Generally it looks to stay weak and lack moisture to stir up rain, so plan for partly cloudy skies and highs in the mid 70s. Friday night will be mostly clear with lows in the low 50s.

Looking into next weekend, it looks fairly dry and pleasant. Saturday will be in the mid 70s for highs, and Sunday in the upper 70s, with partly to mostly sunny skies. Overnight lows will be in the mid to upper 50s.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking into the second week of June, the large-scale pattern calls for a largely zonal pattern but with cooler Canadian air slipping into the Upper Midwest and toe a lesser extent, much of the northern third of the continental United States. This pattern also favors brining in storm systems across the northern United States, leading to the expectation of above-normal precipitation for the period. So slightly cooler than normal and wetter than normal weather is likely for Tompkins County as we press into June and the start of meteorological summer.

Brian Crandall

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