841 FXUS61 KALY 110815 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 415 AM EDT Fri Apr 11 2025 .SYNOPSIS... Light rain and snow will diminish this morning. Low pressure will approach from the mid Atlantic Coast late this afternoon into tonight bringing a mixture of rain and snow back into eastern New York and western New England late tonight through Saturday morning with the greatest accumulations over the higher terrain south and east of Albany, as below normal temperatures continue. Fair and dry weather returns Saturday night into Sunday with temperatures moderating to seasonable levels to close the weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Key Message: - Below normal temperatures continue today with light rain and snow diminishing by the late morning. Discussion: As of 415 am EDT...Low pressure continues to weaken lifting northeast of western NY into the eastern Great Lakes. High pressure is situated near or east of Nova Scotia. Light snow continues over the higher terrain with a mixture rain mixed with some snow in the Hudson/Mohawk Valley. Some weak isentropic lift lingers northeast of the warm front over the Mid Atlantic States. Any additional snow accumulation over the higher terrain will be an inch or so, with a slushy coating to a a few tenths on the grassy surfaces in the valleys. It will be mostly cloudy and cool in the late morning through the afternoon, as attention shifts to developing low pressure over the Piedmont Region into the Mid Atlantic states, as short-wave energy rounds the base of the mid and upper level trough east of the MS River Valley. This lull in the pcpn will last most of the afternoon. Clouds will dominate south of I-90 with perhaps some breaks over the northern most zones. It will be cool with clouds and the east/southeast onshore flow. We did introduce some slight or low chance PoPs for the western most zones (western Dacks, western Mohawk Valley and eastern Catskills) in the late afternoon before sunset with the residual inverted trough over w-central NY and PA. Highs today were lowered a few degrees below the NBM with mid and upper 40s in the valleys and over the hills with mid 30s to lower 40s over the mtns. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... Key Messages: - Medium to high chance (30-60%) of at least 2 inches of snow across the eastern Catskills, Berkshires, Litchfield Hills of CT and the southern Greens, VT late tonight through Sat. - Winter Weather Advisories issued midnight tonight to 2 pm Sat for the Berkshires, and eastern Catskills of western Greene and Ulster Counties. - Medium to high confidence temps moderate closer to seasonable levels to close the weekend. Discussion: Impressive mid and upper level trough continues over the east Coast with low pressure moving from the Mid Atlantic corridor to near the Delmarva Region by 06Z/SAT. A region of upper level diffluence set up over NY and New England. The sfc low strengthens near the left front quad of a mid and upper level jet streak. Atlantic moisture is tapped ahead of the wave with pcpn building back in from south to north gradually prior to midnight south of I-90.The slower progression is noted on the HREFS/3-km HRRR/NAMnest/ARW-WRF. The h850-700 FGEN increases in the northwest quadrant of the storm especially southeast of the Capital Region, northern Catskills and southern VT. Strong upward vertical coupled with dynamical cooling will allow periods of rain and snow to blossom south of the Capital Region initially. The higher terrain will have the best chance for snow early on, especially above 1000 ft. We were concerned about the heavy wet snow potential highlighted in the CAMs with Snow to Liquid Ratios (SLRs) of 6-8:1. SLRs may lower closer to 3:5-1 in the valleys. Total QPF sharply drops off further north and west during the day with one to two tenths over the northwest zones and as much as a half to three quarters of an inch over the southeast extreme. Due to wet bulb cooling lows drop off into the upper 20s to mid 30s Fri night/Sat morning. Heavy wet snow (pcpn snow rates 0.5 to as high as 1"/hr) continue through daybreak especially along the southern VT, Capital District, northern Catskills corridor. The potential was greatest for 2-6" over the eastern Catskills of western Greene and western Ulster Counties for a Winter Wx Advisory due to the strong forcing and east/southeast flow orographic enhancement. 1-2" may occur on the grassy surface in the mid Hudson Valley into the Capital Region. The Berkshires (criteria is 3") looks good for at least 2-4", and an Advisory was raised until 2 pm with some sleet maybe mixing in. NW CT is tricky and we have 1-3" over the Litchfield Hills and 1-2" in the valley. Similar total for the Taconics. Southern VT we were less confident for an advisory yet, and have 2-4" with some high peak totals of 4" or so. Some sleet or spotty freezing rain may mix in. WPC WWD guidance removed all the ice, most the guidance shows isothermal soundings or some sleet moving in late Sat. Overall, Advisories in place for the eastern Catskills and Berkshires and we will monitor for any additions later today. Location north and west of Albany may only get a slushy coating to an inch with the Helderbergs and the Schoharie Valley maybe getting 1-4". The pcpn lightens in the afternoon for some light rain/snow/sleet in the mid and upper deformation zone. As temps warm on Sat pm, rain/snow mix will change back to rain in lower elevations with a light rain/snow mix in the mountains with maybe pockets of sleet. Max temps will be 10-15 degrees below normal with 30s to around 40F over western New England and the southern Dacks/eastern Catskills with 40-45F readings in the valleys. Saturday night the trend continue for the rain/snow or a brief sleet/freezing rain to end early on. Mostly cloudy and cold conditions continue with the coastal wave moving east of the Gulf of Maine. Some ridging will attempt to build in from Midwest/Great Lakes Region. Lows will range from the upper 20s to around 30F over the mtns to lower/mid 30s in the valleys. Low and mid level ridging builds in from the west, as a sfc anticyclone ridges in from the Ohio Valley/Great Lakes Region over NY and New England. Temps rise close to seasonal levels with partly/mostly sunny skies. Highs will be in the mid 50s in the lower elevations and mid 40s to lower 50s over the hills and mtns. Fair and dry weather continues Sun night with lows in the upper 20s to mid 30s. && .LONG TERM /MONDAY THROUGH THURSDAY/... Key Message: - Seasonably mild Monday and Tuesday before a strong cold front Tuesday night ushers in below normal temperatures, blustery winds, and additional rain and higher elevation snow showers for Wednesday. Discussion: We begin the long term on Monday when broad upper level ridging and subsidence expands across the Northeast supporting dry conditions. As the upper level ridge axis slides to our east, southwest flow aloft will promote warm air advection ahead of an approaching warm nose. Thus, we finally will have a break from the string of below normal temperatures on Monday as we trend back seasonable temperatures for mid-April. Chances for rain, however, return by Monday night as a compact/mature closed low in southern Ontario heads eastward dragging its attendant occluded boundary and triple point through the Northeast. The mild air mass ahead of the forcing will support mainly rain as the p-type Monday night. Showers diminish in coverage by Tuesday morning but as the closed low tracks eastward, its trough axis swings through the Northeast sending a sharp cold front through our area. Not only will this send a surge of cold air advection back into the region (850hPa isotherms nearly 2 standard deviations below normal per the NAEFS) but gusty northwest flow and moist/cyclonic flow aloft will also support additional rain and even snow showers for the higher terrain including lake enhanced and upslope snow showers across the southern Adirondacks and southern Greens. Probabilistic guidance shows 50 to 70% chance for west-northwest wind gusts to exceed 30mph with the highest values across the Mohawk Valley, Capital District into western MA. Temperatures struggling to rise out of the 40s combined with blustery winds will make it feel quite chilly on Wednesday. In fact, probabilistic guidance indicates under 20% chance for highs to exceed 50F, except in the mid-Hudson Valley where values range 30- 50%. Rain and higher elevation snow showers diminish Wed night as upper level troughing exits into the Canadian Maritime and shortwave ridging builds in. Winds weaken Wed night but with the chilly air mass still in place, confidence is growing for temperatures to fall near or slight below freezing with the highest confidence in higher terrain areas. Dry conditions return on Thursday with temperatures trending milder and returning back to seasonable levels. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... Through 06 UTC/Saturday...Rain or rain/snow mix showers tonight at ALB and GFL with wet snow at PSF continuing. POU remains mainly dry although rain showers will likely fall at least intermittently. Depending on precip intensity, rain can briefly turn to wet snow at ALB and GFL through 10/11 UTC this morning while PSF likely remains all wet snow. During any steadier periods of snow, IFR vis is likely. IFR cigs will persist at ALB, PSF, and GFL but potentially occasional improve to MVFR so included TEMPO groups. Mainly VRF cigs for POU but occasional MVFR cigs/vis possible and included TEMPO group. Rain and snow exits to the north and east away from the terminals this morning mainly by 11 to 14 UTC. Cigs improve to VFR by 15 - 18 UTC with even breaks of sun. Cigs will fall again towards the end of the TAF period as our next batch of precipitation approaches. Winds remain east to southeast through the end of the TAF period around 5 kts or so for all sites. Outlook... Saturday Night: Low Operational Impact. Slight Chance of SHRA. Sunday: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: Moderate Operational Impact. Chance of SHRA. Tuesday: Moderate Operational Impact. Breezy. Chance of SHRA. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...Winter Weather Advisory from midnight tonight to 2 PM EDT Saturday for NYZ058-063. MA...Winter Weather Advisory from midnight tonight to 2 PM EDT Saturday for MAZ001-025. VT...None. && $$ SYNOPSIS...Wasula NEAR TERM...Wasula SHORT TERM...Wasula LONG TERM...Speciale AVIATION...Speciale