ITHACA, N.Y. — It’s November and climatologically speaking, the time is right to start seeing flakes in the air – albeit briefly and with little in the way of accumulation as of yet. Yes, folks, you may prefer to call it by another four-letter “S” word, but we have a little snow in the forecast for higher elevations before temperatures warm up for the remainder of the week.

Graphic courtesy of NWS Binghamton

Your Weekly Weather

It’s a chilly and mostly cloud afternoon, with clouds thickening as a Canadian low moves east-southeast across the Great Lakes. This system is what’s colloquially known as an “Alberta Clipper” low, a frequent visitor during the cool season that forms in the lee (downstream) side of the Canadian Rockies and moves southeastward into the continental United States, sometimes the Upper Midwest and sometimes the Northeast depending on adjacent jet stream ridges and troughs. These storms are common but usually are not that strong, as forming and passing over the geographic middle of the North American continent limits the amount of moisture available for precipitation.

The precipitation shield with this particular storm will begin moving in around sunset. Temperatures should still be in the upper 30s in Ithaca by this point, so at least in Ithaca and along the lakeshore this should be a rain event with perhaps a few snowflakes mixing in at the tail end in the late evening hours. In the higher elevations, where temperatures are a couple degrees cooler, the change to snow will be sooner, and on the hilltops a coating to an inch of snow is possible. Nothing impressive, but it’s clear that winter is coming. The precipitation will taper off after midnight, leaving mostly cloudy skies and lows in the low to mid 30s.

Monday will be brisk, as behind that Alberta clipper a strong northwesterly flow will shunt colder air into the region. A strengthening coastal low that will absorb the clipper low’s energy will reinforce that flow later in the day. Winds will be breezy from the northwest, gusting to 25 MPH during the afternoon hours. Skies will be mostly cloudy with a few lake effect rain showers and highs in the mid 40s, but with the gusty winds it will feel more like the mid 30s. These winds will slacken and any showers will wither away Monday night as the coastal system moves away, leaving a dry and mostly cloudy night with lows around 30°F.

Tuesday will see high pressures build in from the south, though with locally westerly flow (recall highs circulate air clockwise) it will remain chilly. A few lake-effect rain showers are likely to persist north of Tompkins County, but generally it will be a dry and mostly cloudy day with highs in the mid 40s. Tuesday night will be partly cloudy with winds shifting to light out of the south as the high migrates eastward, and lows will be a little milder, settling into the mid 30s overnight.

A combination of the now-Atlantic Ocean centered high’s clockwise flow and the counterclockwise flow of a second Alberta clipper near the Dakotas will result in a greatly enhanced southerly wind Wednesday, and it will arguably be the nicest day of the week. It will be dry and mostly cloudy with highs climbing into the upper 50s. Some light rain associated with the fast-moving clipper is likely to move in by late evening Wednesday, but the thick cloud cover and moisture will keep overnight lows on the warm side for November, only falling back to the lower 40s.

Thursday will start off on the milder side as Tompkins County remains in the warm sector of the low until after sunset. This low will stay to the north, but will strengthen with moisture from Hudson Bay. While highs will be in the mid 50s, it will be a wet and dreary day as the rain shield associated with the frontal boundary of the low hangs around for practically the whole day, with persistent light rain only finally moving out in evening, behind the cold front. Thursday night will see drier conditions with partly cloudy skies and lows in the lower 30s, as the northwest wind picks up behind the low.

Friday will see high pressure build in from the Western Great Lakes, but this will be a colder northwesterly flow, and while it will be partly cloudy and dry, highs will only be in the mid 40s. Friday night will be partly cloudy and dry as well, but cold, with overnight lows in the upper 20s.

Looking ahead into next weekend, some moderation is likely, with temperatures perking up a few degrees into the upper 40s for Saturday and lower 50s for Sunday. Lows will be in the upper 20s to lower 30s along Cayuga Lake. Both days will be dry with partly to mostly cloudy skies.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Looking ahead into the Thanksgiving holiday week, initial indications don’t suggest any major travel issues, though wetter than normal conditions are likely with a persistent trough in the Deep South. A jet stream ridge will result in a warmer and drier Western U.S., while a trough downstream will bring colder than normal conditions over the Mississippi River Valley. Locally, temperatures are expected to be near normal during the period with slightly wetter than normal conditions, and there are some signs of warmer than normal temperatures by the end of the month we’ll want to keep an eye on.

Brian Crandall

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