Area Forecast Discussion
Issued by NWS Albany, NY
Issued by NWS Albany, NY
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956 FXUS61 KALY 131107 AFDALY Area Forecast Discussion National Weather Service Albany NY 707 AM EDT Sun Sep 13 2026 .WHAT HAS CHANGED... Continued trend of colder min temps for Mon night, especially across the southern Adirondacks where patchy frost is now mentioned. && .KEY MESSAGES... 1) Rain and embedded thunderstorms will continue this morning, especially for areas near and south of I-90, where some locally heavy downpours will be possible. 2) A cold front will bring isolated to widely scattered thunderstorms mainly areas north and west of the Capital Region and southern VT this afternoon and evening. A few storms could produce damaging winds and/or large hail. 3) It will be a mostly dry and cool start to next week with slightly below normal temperatures, with the next chance for showers arriving mid to late week. && .DISCUSSION... KEY MESSAGE 1... Mid-level trough will continue to tracking east-northeast across the northern Appalachians through this morning. A conveyor belt of deep moisture with PWAT`s of 1.75-2" combined with deep warm cloud layers will be favorable for efficient warm rain processes, allowing for areas of moderate to locally heavy rain across much of the region through daybreak, shifting to areas mainly from the Capital Region and areas south/east through mid morning. Rainfall rates of 0.25-0.50"/hour are expected, with locally higher rates within any deeper embedded convective elements and/or narrow banding that develops. Latest CAMs suggest that areas near the I-90 corridor may have one maxima of rainfall associated with mid level F-Gen forcing, while areas farther southeast across the mid Hudson Valley and NW CT may have a second maxima where deeper convective elements and greater low level forcing closer to a developing surface warm/coastal front occur. 00Z/13 HREF 3-hour probs for >3" rainfall at 10-30% across portions of the mid Hudson Valley and NW CT between 8-11 AM this morning, with similar probs for >1" at 50-70% or higher as far north as portions of the Capital Region, Berkshires and extreme southern VT, and these are the areas where ponding of water in low lying/poor drainage and urban areas is more probable. There is also a low probability for isolated flash flooding in some of these areas. Heavy rain should shift east of these areas by late this morning. KEY MESSAGE 2... In the wake of this morning`s rainfall, generally dry conditions are then expected from late morning through at least mid afternoon, despite mostly cloudy skies. Some breaks in the clouds are expected to eventually develop by late afternoon. An approaching cold front is then expected to track into western and central NY later this afternoon, triggering isolated to scattered showers and thunderstorms. Latest HREFs suggest MU CAPE of 750-1250 J/kg develops later today, although is highly dependent on how much sunshine can break through. At this time, at least isolated to scattered thunderstorms are expected to reach the Mohawk Valley and SW Adirondacks around sunset, which should then track east/southeast toward the Capital Region and Lake George/Saratoga region shortly thereafter. Despite waning instability, strengthening mid level winds and approaching upper level support could sustain strong thunderstorms for a few hours even after sunset, should then materialize. A few instances of damaging wind gusts and/or large hail will be possible. The latest Day 1 convective outlook from SPC places most of eastern NY and southern VT within a Marginal Risk (Level 1 of 5) for severe thunderstorms. KEY MESSAGE 3... A much cooler air mass will overspread the region later tonight into Monday in the wake of the cold front. It will be breezy Monday with northwest winds gusting 20-30 mph at times. High pressure will then build overhead for Monday night, providing excellent radiational cooling conditions. Low temps by Tue AM should fall into the 40s for most areas, except 30s across much of the southern Adirondacks and upper Hudson Valley. Patchy frost will be possible across the southern Adirondacks, and will need to monitor in case the potential for more widespread frost potential necessitates frost advisory issuances for these areas. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... Areas of rain, some moderate to heavy, will continue through mid to late morning, resulting in MVFR/IFR Vsbys/Cigs. Rain should gradually taper off later this morning, however MVFR/IFR clouds will likely linger into early afternoon before lifting to VFR. Another line of scattered showers and thunderstorms ahead of a cold front will cross the region from NW to SE between 23Z/Sun-06Z/Mon, which may allow for a brief period of MVFR/IFR Vsbys. In the wake of the front, most areas should remain VFR despite occasional Cigs of 3500-5000 FT AGL. However, some upslope low clouds and MVFR Cigs could linger at KPSF prior to daybreak. South to southeast winds will persist at KALB at 8-12 KT with a few gusts up to 20 KT through sunrise, while remaining light/variable elsewhere during this time. After daybreak, winds will be south to southeast at 5-10 KT through this evening, then will shift into the west to northwest at 8-15 KT toward or after midnight as the front passes. Winds will be stronger and variable in direction in and near any thunderstorms. Outlook... Monday Night: No Operational Impact. Patchy FG. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ DISCUSSION...24/15 AVIATION...24