ITHACA, N.Y. — A cold front is moving through, but with summer in full swing, the cooler air moving in won’t last long. Temperatures will make another run towards and into the 90s later this week, with generally quiet weather expected from Monday morning through Friday evening – right before the holiday weekend starts for most. What will be, will be.

Your Weekly Weather

A line of thunderstorms has just pressed through Tompkins County as it heads eastward, part of a cold front associated with a Canadian low pressure storm system. Reports indicate about 0.25-0.50″ of rain as well as gusty winds with this storm, and a couple warnings have been posted for individual cells in the line this afternoon. The exception has been southern Tompkins County, where there was a gap in the line and rain reports are much less, if any is being reported at all.

This will not be the only round of rain and thunderstorms. High-resolution models are keen on at least a few more lines developing with the heat of the day and the instability conjured up by the impending cold front, and so if you’ll be out this evening or late tonight, have an umbrella handy. Generally, expect about another 0.25-0.50″ of rain by sunrise tomorrow. The front itself should pass through in the early AM hours Monday, which will bring an end to the showers and storms shortly thereafter. It will be overcast between rounds of rain tonight, with lows in the mid 60s.

Monday will see a cooler, drier air mass work in as part of high pressure system entering from the Midwest. This will introduce a northwest breeze, and apart from the few showers primarily east of Ithaca that will clear out around sunrise, it will be a quiet day with decreasing clouds in the morning, and partly cloudy skies during the afternoon with highs in the upper 70s. Monday night will be tranquil with partly cloudy and lows in the lower 50s.

Heading into Tuesday, it looks like another dry day is in store for Tompkins County, with a few passing clouds during the day and highs in the mid 70s. Tuesday night will see mostly clear skies early with a few more clouds towards sunrise, but otherwise quiet with lows in the mid 50s.

There’s a bit of disagreement in the models for Wednesday. An upper-level trough will attempt to swing through and stir up some showers, but the high pressure system in place is fairly expansive and the air mass in place will be quite dry – not the recipe one wants for a rainmaker. At this point, it looks to just an increase in clouds, but don’t be too terribly shocked if a shower or thunderstorm arises. It will be mostly sunny, and an increase in southerly flow with the trough will bring highs into the low 80s.

Behind the trough, the high pressure system, now centered over the Mid-Atlantic, will usher southwesterly flow into the Southern Tier and Finger Lakes. This air will be warmer but not especially humid, at least to start – highs will be in the mid 80s and dewpoints will be in the upper 50s to around 60, fairly comfortable for a warm summer’s day. It will be mostly sunny with only a few passing clouds during the day. Thursday night will host mostly clear skies and lows in the low 60s.

Looking ahead into Friday, the flow becomes stronger, and this will draw hotter and more humid air into the area. Highs will be in the low 90s with dewpoint in the mid 60s, so it will be hot and rather muggy, and you’ll want to take it easy if you’ll be outdoors for an extended period. A cold front will begin to sag into the region later Friday, a slow mover that will likely trigger some showers and thunderstorms late in the day. This will continue through the overnight hours with increasing chances of rain after midnight, mostly cloudy skies and lows in the upper 60s.

The frontal boundary should slowly cross southeastward across Tompkins County Saturday, and it’s looking to be a cooler but unsettled day as that front injects instability into the region. Expect showers and thunderstorms with mostly cloudy skies and highs in the low 80s. Saturday night will be showery with lows in the upper 60s, and Sunday will see a chance of showers early with mostly sunny skies later and a high in the low 80s.

Graphics courtesy of the NOAA Climate Prediction Center.

Extended Outlook

Peering into early July, the large-scale meteorological pattern favors a jet stream ridge over the Great Plains and Ohio River Valley, and troughs over the West Coast and the Northeast. This would indicate cooler-than-normal conditions are likely for the period, as well as slightly enhanced precipitation from being on the edge of the midlatitude jet stream and the prevailing storm track. There’s some risk of excessive heat in the Deep South, but overall the period does not look to be too active from this vantage point.

Brian Crandall

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