Albany, NY WFO Forecast Discussion
000 FXUS61 KALY 301735 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 1235 PM EST Mon Jan 30 2023 .SYNOPSIS... A weak area of low pressure and cold front will push across the region into tonight with periods of light rain and snow. Precipitation will taper off across most areas after midnight except for western areas as lake-effect snow showers will develop. Colder weather is expected on Tuesday with lake-effect snow showers gradually diminishing. An arctic air mass arrives for the end of the week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... .UPDATE...As of 1230 PM EST, the main changes with this update were to tighten up the temperature gradient from north to south as northern areas are running lower than predicted with southern areas running as expected. A few fragments of precipitation have reached areas north and west of Albany producing some light snowfall, but so far little or no accumulation. Activity should become better organized this afternoon and evening, slowly advancing southeastward with time. Still expecting amounts to range from little to none to an inch or two for most areas. Previous Discussion: As of 1030 AM EST, a frontal boundary is positioned from southwest to northeast just to the south of Albany and is now nearly stationary. A weak area of low pressure near western/central Pennsylvania will track northeastward along this front this afternoon and evening. Lift within the surface low and low- level convergence along the front will aid in some light precipitation this afternoon and evening which is already being seen on radar across western/central New York. This activity will increase in coverage across areas mainly north and west of Albany into the early afternoon before slowly shifting south and eastward into tonight. Overall trends support light liquid equivalent precipitation with this system. Many obs across western New York are only reporting visibilities in snow of 1-3SM. As a result, we do expect accumulations to occur slowly. The January sun angle should limit much in the way of accumulations on paved surfaces during the day, especially in the valleys and areas where temperatures will be near or above freezing. In addition, low- level southwesterly flow should lead to some downsloping issues, especially within the immediate Capital District, and this should limit accumulations there. Rain could also mix in at times this afternoon from the Capital District and areas farther south and east. Updates this morning were to tweak QPF/snow amounts per the latest guidance and this trended amounts down slightly for some areas. Will have to monitor if any bands of more moderate snow develop and localized higher amounts could occur; however, forcing is not well aligned within the DGZ per forecast soundings. Many areas will pick up less than an inch of snow with upslope favored areas east of the Hudson River and the Adirondacks/western Mohawk and Schoharie valleys picking up 1-2 inches. Some additional light accumulations will occur across the Adirondacks and western Mohawk Valley tonight due to lake- effect snow showers. In terms of cloud cover, it will be mostly cloudy/cloudy for the Capital District and points north and west with a few breaks of sun possible for areas farther south and east into this afternoon before turning cloudy later today. Widely varying temps are expected today due in part to clouds, the positioning of the front and timing of precipitation. Highs in the 20s to lower 30s are expected for most areas north and west of Albany. Closer to the front from the Schoharie Valley into the Capital District and southern Vermont, highs between 32 and 38 degrees are expected. Farther south and east, highs in the upper 30s to even upper 40s are expected with the highest readings across Dutchess County. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... Snow showers or a period of light snow should be ongoing across portions of the eastern Mohawk Valley, eastern Catskills extending northeast into the Capital Region, Berkshires and southern VT. This area of snow showers or light snow should eventually expand south and east later this evening, with some rain showers possibly changing to snow before ending as far south and east as the mid Hudson Valley and NW CT. Total snowfall accumulations of a coating to 2 inches could occur across portions of the Taconics, Berkshires, southern Greens, extending into the Capital Region and eastern Catskills. Snow should taper from from NW to SE toward daybreak, although a lake effect snowband may develop toward daybreak and impact portions of southern Herkimer County. Lows tonight in the single digits and teens across northern areas, and lower/mid 20s farther south and east. Lake effect snow may continue through early afternoon across the far western Mohawk Valley/Schoharie Valley and eastern Catskills, before shifting south and contracting back to the west in the afternoon. Elsewhere, a mix of sun and clouds is expected, with mid level clouds thickening once again later in the day with the approach of another upper level disturbance. Highs mainly in the 20s and 30s, except only teens across the southwest Adirondacks. Some low level ridging builds into the region Tuesday night into Wednesday. A period of mostly cloudy skies, and perhaps some spotty snow showers/flurries may occur early Tuesday night with aforementioned passing upper level disturbance; otherwise some clearing is expected later at night with at least some sunshine expected Wednesday. However, lake effect snow may develop later in the day into Wednesday night across far northern Herkimer County and northwest Hamilton County, where a couple of inches will be possible. Highs Wednesday mainly in the 20s to lower 30s, except teens across the southern Adirondacks, with lows Wednesday night in the single digits and teens. && .LONG TERM /THURSDAY THROUGH SUNDAY/... Dangerously cold temperatures and wind chills expected Friday into Saturday... The main concern for significant/impactful weather in the long term will be a major (short-lived) cold outbreak that will feature bitterly cold temperatures and gusty winds resulting in dangerously low wind chills. Deterministic/ensemble guidance all indicating an Arctic cold front will sweep southeast across the region Thursday night into Friday morning. Snow showers may accompany the Arctic front, however the main impacts will be from the dangerous cold that will ensue in wake of the front. GEFS/NAEFS indicating impressive 850/925 mb temperature anomalies of -2 to -3 STDEV developing Friday into Friday night. Gusty northwest winds are also expected to develop and persist, which result in wind chills in the -20s to -40s Friday night into Saturday morning. Should these values be realized, Wind Chill Warnings would be needed. Will continue to mention threat in the Hazardous Weather Outlook. It will remain cold Saturday afternoon into Saturday night, but the air mass will already begin to modify as the core of the cold shifts northeast into northern New England and the Canadian Maritimes as a 1040+ mb area of high pressure also shifts east of our region. By Sunday, a SW flow aloft should return resulting in much milder temperatures with highs near to slightly above normal. Chances for snow showers also return associated with warm advection. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... Through 18z/Tue...Mainly BKN to OVC skies across the region at this time with MVFR cigs at ALB and GFL and VFR cigs at POU and PSF. Will likely see this trend continue for the next couple hours, but PSF should see MVFR cigs fill back in by 20z. Also, an area of low pressure will bring scattered light snow showers to the region later this afternoon into tonight. Snow showers will overspread the region from northwest to southeast, and will be accompanied by MVFR cigs and IFR visibilities in snow showers. Some rain may mix in at POU, especially this evening. Total snow accumulation looks to generally be less than an inch at GFL/PSF and less than a half inch at ALB/POU. Snow showers end from northwest to southeast between 4-8z. Vsbys and cigs both return to VFR once snow showers end tonight. VFR conditions continue through the end of the TAF period, except at PSF where a period of MVFR cigs is expected from mid-morning into the afternoon due to northwesterly upslope flow. Winds will be light and variable this afternoon and evening, but pick up to around 5 kt from the northwest tonight after 00z. Winds increase to 5-10 kt from the north/northwest after 6-8z, which continues through mid morning. Then, winds turn more west/northwesterly at around 10 kt behind a cold frontal passage tomorrow morning. Outlook... Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: Low Operational Impact. Breezy. Slight Chance of SHSN. Friday: Moderate Operational Impact. Windy. NO SIG WX. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...KL/Rathbun NEAR TERM...KL/Rathbun SHORT TERM...KL LONG TERM...JPV AVIATION...Main