textproduct: Binghamton

SYNOPSIS

Some light snow showers develop late tonight out ahead of the next system that will produce snow and rain showers through the day tomorrow. A brief period of lake effect snow showers develops tomorrow night. The next winter weather system is forecast to bring a period of accumulating snow to much of the area late Monday night through Tuesday or Tuesday night.

NEAR TERM /THROUGH SUNDAY NIGHT/

Quiet weather will continue this evening, but clouds will increase out ahead of the next incoming weather system. Temperatures fall into the 20s after sunset and hold rather steady overnight. South winds begin increasing after midnight, becoming breezy (10-20 mph, gusts 30 mph) across the Finger Lakes and higher terrain locations before sunrise Sunday. The storm system that is bringing a widespread snowfall across the Midwest and Central Great lakes then heads our way late tonight.

For our area, strong warm air advection develops with the increasing south wind as a mid level warm front lifts north of the area. The area of low pressure will be centered over southern Lower Michigan late tonight, when eventually some light snow will break out, after the drier low level dew points mix out. The highest PoPs before daybreak will be across the northern third of the forecast area, up toward the I-90 corridor. Snowfall amounts will be very light for most locations, with just a dusting to a half inch...with none expected in NE PA. The exception will be the upsloping southerly flow could boost amounts up to 2 inches over far northern Oneida county by 7 AM EST Sunday morning. Periods of light snow continue Sunday morning, mainly for CNY...with only scattered showers in NE PA. Rain eventually starts to mix in for the valleys by midday and afternoon as temperatures rise up into the 30s areawide. Little to no additional snow accumulation is expected for most of the CWA; except again northern Oneida county, where another 1-3 inches of snow will be possible during the daytime hours Sunday. A winter weather advisory remains in effect for northern Oneida County late tonight through Sunday night; for 2-5 inches of snow, with localized higher amounts over the far northeast corner of the county (up to 7" locally).

By Sunday night, a fairly strong cold front pushes through from the northwest. 850mb temperatures fall to around -11C over Lake Ontario late at night. This should allow for a period of lake effect snow showers to develop along a W-NW flow, approximately 300-310 degrees. These lake effect showers and bands could add additional light accumulations over the typical lake effect areas of Central NY. Low temperatures will get quite cold, dropping into the 20s areawide.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/

This period starts off with some lingering lake effect flurries and clouds Monday morning, before skies turn partly sunny for the rest of the day. High pressure will be overhead for the daytime hours, but temperatures remain below average, with highs in the mid-20s to mid-30s areawide.

The main concern in the short term period will be the potential for a widespread accumulating snowfall over Northeast PA and Central NY starting late Monday night through Tuesday or Tuesday night. Current trends with this system have been for a faster arrival time and slightly lower QPF amounts. These trends are due to the latest deterministic and ensemble guidance showing a slightly less amplified and faster moving mid/upper level trough. Current official forecast stuck closer to 13z NBM along with WPC guidance. There remain subtle differences in the 12z deterministic guidance on timing, QPF, temperature profiles and ultimately snowfall amount. Probabilities remain generally steady for 3"+ snowfall over the region; ranging from 25% over the NW Finger Lakes to 50-70% from Binghamton south and east into the Catskills and Poconos. General model consensus is for about 0.25 to perhaps 0.50 inches of QPF from this quick hitting winter weather system. With snow ratios likely between 10-15:1 several inches a widespread accumulating snow is becoming more likely. The snow could impact travel as early as the Tuesday morning commute and lingering through the evening commute. Temperatures start off cold late Monday night and Tuesday morning, well down into the 20s. This cold dense dome of air should help to enhance isentropic lift as the low pressure system approaches. Forecast profiles from the 12z NAM show plenty of vertical motion within the snow growth layer. Exact details such as snowfall amounts are still changing and do remain uncertain at this time. Some rain or mixed precipitation could mix in with the snow across the Wyoming Valley and other lower elevation locations in NE PA. When/if confidence grows in snowfall amounts, winter weather headlines may be needed. Continue to check back for forecast updates as confidence in the details of this weather system increases in the coming days.

The snow likely tapers off Tuesday evening, with just some snow showers or flurries lingering overnight as the low pressure center strengthens off the northern New England coast Tuesday night. Colder air filters in behind the departing system on a NW flow, with overnight lows dipping down between about 15-25 F.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

The main story for the middle and end of the week will be a cold wintry weather pattern persisting over the region. Wednesday features generally dry, calm, partly sunny and seasonable weather. Then a strong cold front looks to sweep into the area late Wednesday night or Thursday; bringing snow showers and perhaps even some snow squalls. 850mb temperatures drop to around -18C or even briefly low, along with sub 516dm thickness in the 1000-500mb layer. This will cause lowering surface temperatures Thursday and especially Thursday night. In fact overnight lows in the single digits to mid-teens are expected, with apparent temperatures around or slightly below zero possible. Chances for on and off snow showers lingering into Friday or next Saturday with temperatures remain at or below normal values for early December.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

VFR conditions are expected through about 06Z tonight, then a period of light snow is expected to be around through 10-12Z that is expected to produce mainly MVFR restrictions, but occasional IFR visibilities can be possible at SYR and perhaps even RME.

Late tomorrow morning through the afternoon, varying conditions mainly between VFR and MVFR are expected with scattered snow showers that can mix with and even change over to rain during the afternoon and evening.

LLWS also cannot be ruled out at SYR late tomorrow morning into the afternoon. There is also a possibility for LLWS at RME, ELM and AVP during the afternoon, but confidence is low to include at this time.

Outlook...

Sunday night...Occasional restrictions possible in lake effect snow showers, mainly at at RME and SYR.

Monday...Mainly VFR.

Late Monday night through Tuesday...Snow possible and associated restrictions.

Wednesday...Mainly VFR; spotty lake effect snow showers are possible around SYR and RME.

Thursday...Occasional restrictions possible in scattered snow showers, especially at the Central NY terminals.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Winter Weather Advisory from 1 AM Sunday to 1 AM EST Monday for NYZ009.