694 FXUS61 KBUF 091037 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 637 AM EDT Mon Jun 9 2025 .SYNOPSIS... After some brief drying this morning, things will become much more active this afternoon with numerous showers and thunderstorms developing. Some of these storms may produce locally heavy rainfall and gusty winds through the afternoon into the evening, with these drenching thunderstorms continuing the heavy rain threat through the overnight hours. && .NEAR TERM /THROUGH TONIGHT/... A mid level low over the western Great Lakes with several shortwave troughs pinwheeling around the feature will impact our weather for today and tonight. Deepening moisture and strengthening shear profiles will bring the potential for thunderstorms with strong wind gusts and locally very heavy downpours during the afternoon and evening hours. Showers east of Lake Ontario will continue to push northeast through the morning. A few light showers over Lake Erie are approaching the WNY area this morning, but should mostly dissipate by the time they reach WNY. Focusing a bit more on this afternoon and evening, several factors are coming together for a potentially active time period. A belt of southerly flow of 50 knots across far western NY will lie under the front entrance region of an upper level jet that is rounding a deepening mid level low over the central Great Lakes. Height falls and diffluent flow will aid in broad scale lift. In the lower atmosphere, MUCAPE values continue to trend upwards, with over a 1000 J/KG of instability over portions of our region this afternoon and evening south of Lake Ontario. Bulk shear values of 40+ kts in these areas will also support the potential for severe thunderstorms The axis of a +1SD PWAT anomaly will lie over our region this afternoon and evening, that with a boundary layer flow becoming parallel to an approaching cold front will encourage training cells. While the threat for damaging winds from severe thunderstorms will be mainly concentrated from the Genesee Valley/Finger Lakes region westward through the afternoon and early evening hours, the threat for locally heavy rainfall will impact our entire region with basin average rainfall amounts of an inch plus possible across a good portion of our area from the mid afternoon through the overnight. Heavier rain and convection ends from west to east late tonight, with some lingering patchy fog possible through the night as low level moisture hangs around and air temperatures settle back to near the dewpoint. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... The cold front will ever so slowly exits off to our east on Tuesday, with the greatest coverage of showers east of Rochester in the morning. That said...there may be some diurnally driven showers or an isolated thunderstorm that re-fire during peak heating hours well inland from the lakes. Otherwise...cooler as H850T`s fall into the single digits with highs in the upper 60s to low 70s. The mid-level trough exits off into New England Tuesday night, which will allow for drier weather to take hold across the entire region. It looks generally dry for most locations Wednesday but we still could see a shower or two across the North Country and St. Lawrence Valley. A shortwave trough dropping southeast across Ontario is then advertised to drag a cold front thorugh the area Wednesday night with a better chance for showers or a thunderstorms. This cold front stall out near the NY/PA line Thursday through Friday bringing a continued chance for showers and thunderstorms. && .LONG TERM /FRIDAY THROUGH SUNDAY/... A subtle shortwave tracking through the mid-Mississippi Valley will enhance chances for showers and thunderstorms Friday through the weekend. Placement and overall coverage will then be determined by the exact placement of the aforementioned stall front. Otherwise...temperatures will be near to a bit below normal with upper 60s to low 70s. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... A warm front presses north of the area, with a break in the rain showers expected for the morning hours. While the Southern Tier likely stays locked in the MVFR/IFR range through the first half of the day, expect a several hour period of VFR across the lower terrain south of Lake Ontario, with decks even scattering out in some places as our area becomes firmly entrenched in the warm sector. A cold front will then approach western NY this afternoon with a line of showers and thunderstorms along and ahead of the boundary. The front will slow its eastward progression as it eases across western NY into the Finger Lakes through the afternoon into the early evening hours. Expect widespread rain and thunderstorms featuring the potential for locally heavy rain and strong wind gusts. Flight conditions will lower to IFR, and possibly LIFR in heavier storms, with MVFR predominant outside of heavier activity. Far western NY may start to see some improvement by around 6Z. Tonight, widespread showers and embedded thunderstorms to start the period with LIFR/IFR flight conditions. Activity ends from west to east overnight, with patches of fog lingering through the night. Outlook... Tuesday...VFR/MVFR with a chance for showers and thunderstorms. Likely VFR and dry for KBUF/KIAG. Wednesday...Mainly VFR with a chance of a few showers east of Lake Ontario. Thursday and Friday...Mainly VFR with a few showers and thunderstorms around. && .MARINE... Winds will veer more southerly to southwesterly through the day today and remain through Tuesday behind a cold front that will cross the lower Great Lakes this afternoon and evening. As a pool of cool air associated with the mid level low passes over the lower Great Lakes Tuesday and Tuesday night, a modest chop will again develop on the lakes. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...Flood Watch from 2 PM EDT this afternoon through late tonight for NYZ003-004-012>014-019>021-085. Flood Watch from 5 PM EDT this afternoon through late tonight for NYZ005-006. MARINE...None. && $$ SYNOPSIS...JM/Thomas NEAR TERM...SW/Thomas SHORT TERM...AR LONG TERM...AR AVIATION...JM MARINE...JM/Thomas