ITHACA, N.Y. — We knew we couldn’t escape it forever. With a hefty shot of polar air coming mid-week, it’s looking likely we’ll see are first flakes of the year, perhaps in measurable quantities Thursday night into Friday morning.

Graphic courtesy of the Northeast Regional Climate Center.

Weather Recap

October 2019 will go down in the record books as a warm and wet month. Temperature-wise, the average temperature of 50.0 °F comes in a modest 1.3 °F above normal. The Northeast Regional Climate Center’s database appears to be offline for the moment, but suffice it to say, 1.3 °F above normal won’t be all that noteworthy in the seasonal rankings.

Graphic courtesy of the Northeast Regional Climate Center.

What is noteworthy, however, is the amount of rain received during the month of October. The amount of 5.35″ is well above the normal of 3.42″ for the month, and given the statistical methods of the climate data, is actually missing the Halloween night downpours, since the data for 8 AM onward on the 31st would actually be recorded on November 1st. The Ithaca-Tompkins airport, which follows the more typical calendar day format, recorded 6.12″ of rain during the month of October.

While Ithaca’s climate ranking data isn’t available at the moment, it’s not a big leap of the imagination to see this as being in the top 10% of wettest Octobers, if not top ten since records began in 1893. According to the NRCC, Binghamton recorded 7.85″, its third-wettest October on record. Syracuse had its fourth-wettest, with 6.88″. Burlington, Vermont tops us all – with 8.50″ of rain, it had the wettest October in its recorded history.

With that soggy month in the archives, November is off to a much cooler start, and as we’ll see this week, it’s only going to get colder from here.

Your Weekly Weather

We’ll start the week off quiet and seasonably cool, but the meteorological regime changes as a low pressure system moves from our west to north, sweeping in a potent plume of cold air from polar Northwest Canada and Alaska. The large-scale setup is reversing from last month; a persistent ridge of warm air will build over the Western United States, forcing cold air and storm systems to slide around the ridge and sink into a persistent trough over the eastern two-thirds of the country.

The result will be frequent shots of abnormally cold air even by November standards, but the trough’s edge will be far enough south to direct at least some storm systems southward. However, the cold air, in combination with the warm waters of Lake Ontario and Lake Erie, will turn on the lake effect machine and potentially some substantial rainfalls or even snowfalls downwind, including Tompkins County if the fetch angles itself in a favorable northerly direction.

At the moment on this brisk Sunday, a few weak lake-enhanced showers have traversed the area, but they’re dying down as the atmospheric energy provided by the heat of the day dissipates. The cloud cover will break down somewhat as high pressure builds in front the Mid-Atlantic and mostly cloudy skies give way to partly cloudy conditions, and temperatures will slide back substantially with the westerly wind, with lows in the low 30s.

Monday will be a fairly quiet and seasonable day, as the high pressure system to the south shifts eastward. The southerly breeze following a weak warm front will do little to heat things up, given the immense amount of cold air pumped into the continental U.S. as a result of the powerful Halloween storm. Highs will top out around 50 °F. Partly cloudy skies will cloud over by the afternoon as a low pressure system strengthens over the Western Great Lakes and comes close to the Southern Tier. With this cloud cover and the southerly wind, temperatures won’t fall much overnight, only to about the low 40s as we head into Tuesday morning.

Some rain showers will be in the area Tuesday morning with the low to the west, but they’ll be light and sporadic, with totals less than a tenth of an inch. These will wind down by afternoon as the low moves northeast and away from Tompkins County. The southerly flow ahead of the low (counterclockwise circulation) will pump in some milder air, with temperatures in the low to mid 50s, about the warmest we’ll see this week. As the low continues to move northeast, we’ll find ourselves on the southern end of its circulation, meaning westerly winds, and a reduced tap of mild air, and then finally, a cold front associated with the low sweeps over us when the low crosses our longitude. It will cool off as the clouds break up somewhat, with a low in the low 30s Tuesday night.

Wednesday will be the last of the seasonably cool days as high pressure begins to build in from the southwest. Highs will be in the upper 40s under partly cloudy skies. With the westerly winds, lake effect rain is likely downstream of Ontario and Erie, so the cloudiness will be persistent. Wednesday night will be mostly cloudy, with the chance for some snow showers and a low in the mid 30s.

Thursday is where the forecast gets tricky. The models are clear that a low pressure storm system is likely to develop off the Mid-Atlantic coast. This will draw colder air down from Canada, and it will be unseasonably cold heading into the weekend. What is not clear is the exact location of the low, which has been inconsistent across models and consecutive runs. If it’s further north and closer to us, we’ll likely see a substantial rainfall turn into a substantial snowfall Thursday night into Friday, as it brings moist oceanic air into the Southern Tier. If the storm stays further south as the latest runs have suggested, then there will be little in the way of precipitation, it’ll be a fairly dry cold front with some light rain and a coating of snow Thursday night into Friday.

Thursday is one of those classic cases of “hope for the best, prepare for the worst”. Keep an eye on NWS Binghamton’s Winter Weather webpage here in case the models start trending back towards the nastier, snowier outcome.

At the moment, plan for a cloudy day Thursday with scattered rain showers, a blustery northwest wind and a high in the low 40s. Thursday night will see the rain showers change over to snow as temperatures cool off during the evening, and right now the accumulations are expected to be light, from a coating to perhaps an inch in the hills east of Ithaca, and a chilly low in the mid 20s.

Friday will be very cold for late fall, as the relentless northwest wind prevents the partly sunny skies from having much of an effect. Highs will be in the upper 30s in urban Ithaca, and mid 30s is more likely in the outlying towns, and especially on the hills and in communities to the north (Lansing, Trumansburg). Friday night will be the coldest night of the year so far, with partly cloudy skies, some lake effect snow showers north of Ithaca, and a low in the low 20s.

The weekend will be quiet if cold. Saturday will be mostly cloudy and dry with a high in the mid to upper 30s. Saturday night will be mostly cloudy and in the mid 20s. As the northwest flow weakens, Sunday will moderate though still below average, with partly cloudy skies and a high in the mid 40s.

Graphic courtesy of the NOAA Climate Prediction Center.

Extended Outlook

For those looking for a break from the cold, you won’t it here, or just about anywhere in the eastern U.S. The persistent trough in the jet stream will allow for repeated shots of cold Arctic air to plunge into the region from the Northwest, keeping temperatures well below normal and potentially setting off snow events; it appears likely some measurable snows will come in either this week or next. This pattern is expected to weaken but otherwise be present through the second half of the month. Sorry folks, sh…erm, snow happens.

Brian Crandall

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