textproduct: Binghamton

WHAT HAS CHANGED

Snowfall totals were adjusted to better match the previous forecast. Winter Weather Advisories were issued for most of central NY as well as Bradford and Susquehanna Counties in PA.

KEY MESSAGES

1) Rain today transitions to snow tonight as a deep trough moves through leading to accumulating snowfall across the region.

2) Cold and snowy pattern continues through the weekend and into early next week.

DISCUSSION

KEY MESSAGE 1...

An upper level trough will dig over the eastern US today and as it does, a weak surface low will develop on its leading edge. While conditions will initially start out dry, some scattered showers will move into the region prior to midday. Rain becomes more widespread this afternoon as the low approaches the region. Tonight, the low will pass through and bring a cold front with it leading to rain transitioning to just snow. As it does, wet surfaces may become icy as temperatures approach and fall below freezing. Timing of this rain to snow transition is a little uncertain as dynamic cooling could lead to a quicker transition to snow than forecasted. Snow will generally be light but 850mb FGEN banding indicates that localized heavy snow will be possible but exactly where remains uncertain. The most uncertainty would be a broad area extending from PA's Northern Tier into central NY. Snow will gradually end Thursday morning into early Thursday afternoon as the low moves into New England.

Following the departure of this system, lake effect snow develops under west to northwesterly flow. This will result in additional snowfall for the eastern Finger Lakes and Mohawk Valley regions through Thursday night. A ridge of high pressure then builds into the region Friday morning, bringing an end to the lake effect snow.

Models remain slower and wetter with this system. For tonight, NBM guidance seemed far too low for QPF as the initial resultant snowfall forecast was cut in half from the previous update. Using a blend of the previous forecast, NBM, and Consall guidance, QPF was bumped up and SLRs were also adjusted. This increased snowfall significantly and is closer to what the previous forecast had. This forecast is in relatively close agreement to what WPC is forecasting as well. There are some indicators that this system could potentially overperform, at least locally. As previously mentioned, there could be a quicker transition to snow and localized banding all could lead to higher snowfall amounts than currently forecasted. As of now, this forecast has totals that fall within advisory criteria. A Winter Weather Advisory was issued for tonight through early afternoon tomorrow for most of central NY and Bradford and Susquehanna Counties in PA. For the counties impacted by the following lake effect snow, the advisory is in effect until Friday morning.

Temperatures will be in the 40s today but fall below freezing following the cold front. To end the work week, temperatures will only climb into the 20s before falling into the single digits and teens overnight.

KEY MESSAGE 2...

Under a broad trough, the cold and snowy pattern will continue through early next week. Another shortwave trough will dig over the eastern US this weekend. With it, a weak clipper system will pass north of the region and will bring a chance for scattered, light snow showers to the region Saturday and Sunday. A more organized system moves over the Atlantic late Sunday but is not expected to have any impact for our region. This trough will also bring a surge of colder air leading to temperatures going from the 30s on Saturday to 20s on Sunday. Another surge of colder air is expected early next week as a more broad shortwave swings through. There is some uncertainty on how cold this surge will be though early next week looks to be blustery with temperatures trending even colder and gusty winds expected. Any snow early next week will be in the form of lake effect and mainly limited to central NY.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

VFR conditions are expected to start today, but ceilings will gradually lower throughout the day, resulting in MVFR ceilings moving in by the late morning/early afternoon from south to north. Rain will also be moving in from south to north this afternoon, which may eventually bring IFR visby restrictions as well. By this evening, IFR ceilings will likely move in. Rain will gradually mix with and eventually transition to snow this evening, which will result in widespread IFR-or-worse visbys and ceilings. Gradual improvement from west to east is expected very late in the period (closer to 12Z Thursday).

Outlook...

Thursday through Thursday night...Restrictions likely with lingering snow showers, especially at the Central NY terminals.

Friday through Friday night...Mainly VFR, although occasional restrictions possible at KRME and KSYR with some light snow showers.

Saturday through Sunday...Restrictions possible in scattered snow showers.

BGM WATCHES/WARNINGS/ADVISORIES

PA...Winter Weather Advisory from 7 PM this evening to 1 PM EST Thursday for PAZ038-039. NY...Winter Weather Advisory from 7 PM this evening to 7 AM EST Friday for NYZ009-017-018-036-037. Winter Weather Advisory from 7 PM this evening to 1 PM EST Thursday for NYZ015-016-022>025-044-045-055-056.