FXUS61 KBUF 021433 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 1033 AM EDT Fri May 2 2025 .SYNOPSIS... A cold front moving across the area will bring renewed chances for showers and a few thunderstorms this afternoon. A large area of low pressure will then develop and stall over the Ohio Valley this weekend, resulting in chilly and wet weather much of the time. Unsettled weather will last through the first half of next week as slow moving low pressure meanders from the Ohio Valley towards the east coast. && .NEAR TERM /THROUGH TONIGHT/... A cold front attendant to low pressure crossing southern Quebec will slowly sag across western and north-central NY today. As the front sags into the area, expects some scattered showers, and then a few thunderstorms by this afternoon, mainly from the Southern Tier into the Finger Lakes to the southern Tug Hill region. There is a low chance that an isolated stronger storm or two could develop across these aforementioned areas, with the potential to produce localized strong wind gusts and perhaps some hail. Farther north of this boundary, shower chances will be much lower but a complete dry forecast can't be guaranteed. The cold front stalls out over or just southeast of the area tonight. With the loss of daytime heating, just some scattered light rain showers and maybe a rumble of thunder will linger through the evening hours into the early overnight. A wave of low pressure will then move northeast along the boundary, bringing the likelihood for rain showers back into western NY late tonight. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... A closed cutoff low will slowly spiral across the Corn Belt States this period, with weak surface low reflected at the surface over the Ohio Valley. Deep moisture along a stalled baroclinic boundary that is draped across New England to the Ohio Valley will maintain scattered to numerous rain showers throughout the period. Rainfall through the weekend will total a half to one inch...though lower amounts are possible for the SLV which will lie on the northern gradient of the stalled frontal boundary/precipitation axis. Coolest daytime highs for this weekend will be south of Lake Ontario where a northeast flow over the cold lake waters will slow the daytime warming along the shoreline and inland, especially on Sunday when the flow will be a little stronger. && .LONG TERM /MONDAY THROUGH THURSDAY/... As the closed low spirals eastward our low level flow will veer from the northeast to more southeasterly for Monday. This will promote a milder pattern. With this milder pattern will come increasing instability, that coupled with increasing lapse rates under the pool of cold air aloft (upper level low) deeper convection will be encouraged, with thunderstorm chances increasing through the afternoon and evening hours. Showers, and perhaps a few thunderstorms linger Tuesday and Wednesday with the passage of the closed low aloft, with drier air Thursday allowing for a likely dry day...though plenty of cumulus clouds forming within the northwest cyclonic flow aloft. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... Low-level moisture and showers along a slow moving cold front will bring periodic lower vsbys and cigs (MVFR-IFR) this morning. Most areas will return to VFR at some point this afternoon (exception may be higher terrain). As instability increases with daytime heating this afternoon, do expect showers to increase in coverage ahead of the front along with a few storms, mainly from the western Southern Tier to the Finger Lakes into the southern Tug Hill region. Any flight restrictions with this activity will be intermittent and localized within any heavier showers or storms that develop. Cold front continues to only very slowly press southeast tonight. Further inhibiting frontal progression will be a wave of low pressure riding northeast along the boundary that will bring more widespread showers back in across western NY by late tonight. Increasing moisture ahead of the this next round of rain will bring deteriorating flight conditions with MVFR/IFR developing across the western Southern Tier this evening, and MVFR across much of the remainder of the area. Exception may be toward far northwestern areas (KIAG/KART) farther removed from the front where conditions may not fall below (low) VFR. Solid IFR conditions will expand from the Southern Tier to the Finger Lakes second half of tonight, with MVFR likely for all remaining areas by early Saturday morning. Outlook... Saturday through Tuesday...Occasional showers with areas of MVFR/IFR. && .MARINE... SSW wind flow will continue to produce sub-small choppy conditions through tonight, as a cold front slowly moves southeast across the area. Mainly light northeasterlies can then be expected late tonight through Saturday night with no more than some light chop on the Lakes. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...AR/JM NEAR TERM...AR/JM SHORT TERM...Thomas LONG TERM...Thomas AVIATION...AR/JM MARINE...AR/JM