ITHACA, N.Y. — A summer-like start to the week will feel more like March by mid-week as a complex storm system setup lingers over the region for a few days, drawing down large amounts of cold Canadian air. It’s nothing too severe, but after Monday, you’ll want to hold off on the outdoor activities until late in the week.

Your Weekly Weather

It’s a warm spring Sunday in Ithaca thanks to a surge of warm air ahead of a storm system over the Upper Midwest. Interestingly, the surge of warm air is running up against an “backdoor” cold front that moved westward into Eastern New York, resulting temperatures from New York City and Albany in the 50s and lower 60s, while from about Syracuse westward temperatures are in the mid 70s to mid 80s.

With the frontal boundary of that low still far to the west, the remainder of Sunday will be quiet, though there is enough moisture and instability in the air for an isolated shower or thunderstorm across the Finger Lakes and Southern Tier. Temperatures have topped out in the low 80s around Tompkins County. There will be some increasing clouds after sunset but it should remain dry overnight, with mild lows in the low 50s.

Monday will start off partly to mostly cloudy, but the frontal boundary associated with the low, now to the north over Canada, begins to push into Upstate New York Monday afternoon, with the first rain showers reaching Tompkins County by late afternoon or early evening. With high pressure over Southern New England, the front will slow down as it moves eastward, so expect a cloudy and rainy night Monday, with periods of light to moderate rain, maybe a few embedded thunderstorms between midnight and sunrise, with lows in the low 50s. New rainfall amounts will be between one-tenth and one-quarter of an inch.

A reinforcing low over the Western Great Lakes should help shunt the front eastward Tuesday, and that should end the steadier rain, though showers will persist through the afternoon. Skies will remain mostly cloudy to overcast, and it will be considerably cooler, with highs in the low 60s. That reinforcing low should move in Tuesday night, which will keep the cloud cover around and spur the redevelopment of scattered rain showers after midnight, and maybe a few snow showers at the higher elevations towards morning. Lows will be in the mid 30s.

Wednesday just ends being a raw, unpleasant day as that upper low interacts with a developing coastal system, and draws in large amounts of cold air on the backside of its counterclockwise circulation. That northerly flow will trigger some lake-enhanced rain and snow showers, and it will be much colder than normal, with mostly cloudy skies and highs only in the mid 40s. New rainfall amounts will be less than one-tenth of an inch. Wednesday night will see drier conditions as the combined low pressure system moves east, and it will be mostly cloudy overnight with lows in the low 30s.

Thursday offers some improvement in conditions as the low is well to the east, but it will strengthen, and the sheer size of it will allow to continue to funnel cold air into Upstate New York. Skies will turn from partly cloudy to near-clear by late in the day as high pressure moves in from the northwest. However, a stiff northerly wind will keep temperatures confined to the upper 40s for highs. Thursday night will see the winds slacken, with partly cloudy skies and a low in the mid 30s.

Friday is marginally better as high pressure moves overhead. There will be mostly sunny skies with a high in the mid 50s. Friday night will be partly cloudy and dry with lows in the mid 30s.

A storm system over the Midwest will struggle to press eastward next weekend, so it’s looking fairly dry and maybe a touch on the cool side for now, with partly cloudy skies and highs in the upper 50s and low 60s.

Graphics courtesy of the NOAA Climate Prediction Center

Extended Outlook

Looking into the first week of May, the pattern generally calls for persistent jet stream troughs over the Pacific Northwest and Eastern Great Lakes, with colder than normal temperatures likely. A weak ridge over the Central United States will be favorable to increased precipitation as Gulf Moisture flows up the Mississippi River Valley, but locally precipitation should be near-normal.

Brian Crandall

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