The Finger Lakes and Central New York will have a mostly dry, warmer Saturday before showers spread across the region tonight. Another round of scattered showers and thunderstorms could follow Sunday as a cold front moves through, then cooler air takes hold Monday.
The change will be gradual during the day, according to the National Weather Service offices in Buffalo and Binghamton. Much of the region should stay rain-free through the afternoon, even as clouds increase and humidity rises. Rain becomes more likely Saturday evening and overnight, especially from the Finger Lakes east toward Syracuse and south into the Southern Tier.
Saturday starts dry, then turns unsettled
Sunshine and some high clouds will give way to a cloudier sky as southerly winds bring warmer, more humid air into the region. Rochester could see a mostly sunny start, while parts of the central and southern Finger Lakes will have more cloud cover as the day goes on. Highs will generally reach the upper 70s to lower 80s, with a forecast high near 82 in Rochester, 79 around Geneva and 81 in Syracuse. The Elmira area is expected to stay closer to the mid-70s.
Patchy fog is possible in a few sheltered valleys early Saturday, especially around the Southern Tier, but its extent is uncertain. Otherwise, the first part of the day looks relatively quiet. The approaching warm front should bring only a few showers into most places before late afternoon.
The chance for a shower or thunderstorm develops first farther west and across the Southern Tier during the afternoon. The Buffalo office expects showers and isolated thunderstorms to shift east toward the Finger Lakes by evening. The Binghamton office expects most of its New York forecast area to remain dry during daylight hours, although a few showers could arrive west of Interstate 81 late in the day. That difference is chiefly one of timing, not a forecast for an all-day rain.
Thunderstorms Saturday are not expected to be severe. A few showers could produce locally heavy rain, particularly if they repeatedly cross the same spot in the western Southern Tier late in the afternoon or evening. The Buffalo office describes the isolated flooding risk there as low; the possibility does not extend uniformly across the Finger Lakes and Central New York.
Southerly winds will become more noticeable during the day, generally around 5 to 12 mph in the local forecasts. Humidity will also rise from Friday's more comfortable levels, setting up a milder night even where afternoon showers hold off.
Rain spreads Saturday night
Showers are expected to become more widespread Saturday night as the warm front and a surge of moisture move across the region. Thunder is possible in some areas, but the main overnight development is the expansion of rain rather than a widespread severe-storm threat. Forecasts for Geneva, Ithaca and Syracuse show a high likelihood of showers and thunderstorms overnight; the chance is lower around Rochester.
The rain will not be distributed evenly. The Binghamton office places the greatest potential for locally heavy rainfall over northeastern Pennsylvania and the Catskills, south and east of much of the Finger Lakes. It says localized flooding issues cannot be ruled out late Saturday night, while widespread flash flooding is not anticipated. Parts of the Southern Tier could see a more substantial soaking than areas farther north, but the position of the heaviest bands remains important.
Current point forecasts call for about a tenth to a quarter of an inch around Geneva and Syracuse Saturday night, roughly a quarter to a half-inch around Ithaca, and about a half to three-quarters of an inch around Elmira. Those amounts are forecasts for specific locations, not a guarantee for every neighborhood. Where rain concentrates in narrow bands, totals could differ sharply over short distances.
Clouds and the incoming humid air will keep overnight temperatures much warmer than early Saturday morning. Lows are forecast in the lower to middle 60s across much of the region, including about 65 in Geneva and Syracuse and 63 near Ithaca and Elmira. Rochester is forecast near 66.
Sunday brings a second chance for storms
The overnight rain may ease for a time Sunday morning. A separate round of scattered showers and thunderstorms is possible in the afternoon as a cold front crosses the Finger Lakes and Central New York. The precise timing of that front, the amount of early clearing and the coverage of storms are still uncertain.
If enough sunshine breaks through before the front arrives, a few storms could strengthen. The Buffalo office identifies an isolated severe-thunderstorm possibility from the western Southern Tier through the Finger Lakes into Central New York, with damaging wind and large hail the potential hazards. The Binghamton office also notes a chance for isolated gusty storms, while saying severe storms are not expected across its area at this point. Neither outlook describes a widespread severe-weather event.
The outcome will depend in part on whether morning showers leave enough time for the air to warm and become unstable. If clouds and rain persist longer, the afternoon storm potential may be more limited. Even where thunderstorms occur, their coverage is expected to be scattered rather than continuous across the region.
Sunday will stay warm before the cooler air arrives. Highs are forecast around 78 in Rochester, near 79 in Geneva, around 80 in Syracuse and in the lower 80s near Ithaca and Elmira. A few showers or storms could linger Sunday night as the front and an upper-level disturbance move away, with lows falling into the 50s by Monday morning.
Cooler Monday, then a midweek change
Monday should feel markedly cooler and less humid behind the front. High pressure is expected to bring mainly dry weather, although a brief early shower or some lake-influenced clouds cannot be ruled out southeast of Lake Ontario, including the corridor between Rochester and Syracuse. The Binghamton office says northwesterly flow could leave its area cloudier than current forecasts indicate.
Afternoon highs Monday are forecast in the mid to upper 60s for much of the Finger Lakes and Central New York, roughly 10 degrees lower than Sunday's readings in many places. The current local forecasts put Rochester near 67, Geneva near 66 and Syracuse near 68. Skies should improve where early clouds or showers develop, and Monday night may cool into the 40s in some inland valleys while other communities remain near 50.
Tuesday looks mainly dry as high pressure shifts east. Temperatures should recover into the 70s, though the warmer air may take longer to reach parts of the Southern Tier than the Rochester area. Current forecasts place highs in the lower 70s around Elmira and Geneva and the middle 70s near Rochester and Syracuse. Humidity is expected to rise again as the week progresses.
Another frontal system could bring periods of showers and perhaps thunderstorms by the middle of the week. The Buffalo office notes that the boundary may stall near the region; the Binghamton office also expects a return to warmer weather and scattered precipitation. The timing, storm coverage and placement of any heavier rain remain less certain several days out, with the next rain chance developing as early as Tuesday night in parts of the western and central Finger Lakes.
Check the latest forecast at the FingerLakes1.com Weather Center.
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