textproduct: Binghamton

SYNOPSIS

A weak weather system will bring scattered snow showers and lake effect flurries into tonight. High pressure briefing builds over the area for Monday, bringing partly sunny but chilly conditions. A low pressure system then tracks up along the east coast bringing a period of widespread accumulating snow to the region Monday night into Tuesday. Remaining cold with chances for snow showers heading into the middle and end of the upcoming work week.

NEAR TERM /THROUGH MONDAY/

A low pressure system is tracking north of the area across southern Ontario this evening. A cold front will cross the forecast area this evening into tonight. This will bring a much colder air mass to the area, as 850mb temperatures fall to around -10C late at night. This colder NW flow will bring a brief period of lake effect snow showers off of Georgian Bay, Lake Ontario and perhaps even the Finger Lakes. Accumulations will be light under 1 inch. The winter weather advisory does continue for far northern Oneida county, where localized additional amounts are to two inches are possible.

Clouds and a few lingering lake effect snow flurries continue early Monday morning off of Lake Ontario. Skies gradually clear, becoming partly to mostly sunny for the afternoon hours. With cold air aloft (-10C at 850mb) remaining in place through the day, it will be cold with highs only in the 20s to lower 30s in most locations. NW winds decrease through the day as high pressure builds overhead.

SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/

***Widespread accumulating snowfall expected late Monday night through Tuesday; Winter Storm Watches issued for parts of the CWA***

High pressure starts to slide east after midnight Monday night, with moisture quickly increasing from the Ohio Valley. Current guidance is starting to come to a consensus that snow will quickly overspread CNY/NE PA between about 2-7 AM early Tuesday morning. There remain rather significant model differences in regards to the predicted track and strength of a developing low pressure system across the Southeast US, that will track up along the Mid-Atlantic coast and toward southern New England by Tuesday afternoon. The NAM continues to be the most amplified and tracks the low the further NW; this solution would bring heavier QPF/Snow further NW across our CWA, while at the same time it would bring in milder air, with mixing or rain developing in NE PA. The 12z ECMWF remains less amplified and further southeast with the low track; bringing less QPF and snow to our region. The 12z GFS and CMC-REG models are generally middle of the road solutions, with the low track, QPF and snow amounts between the more outlier NAM and EC solutions. 12z GEFS nudged northwest with the low track, bringing slightly higher QPF to our CWA compared to the 00z run. Also of note is that the 12z ECMWF Ens mean also nudged QPF amounts a bit higher (compared to the 00z run) for our area, especially where the watches are now in place.

Overall, considering the remain model discrepancies, stuck close to the NBM and WPC data for the official forecast. With increasing probabilities for greater than 6 or 7 inches of snow based on the consensus data, and in collaboration with surrounding WFOS/WPC decided to go ahead and issue a Winter Storm Watch for all of our NE PA zones, Catskills and portions of the NY Southern Tier/Susquehanna region of CNY. If further NW trends continue then this watch area may need to be expanded and/or eventually upgraded to a warning...if the more southeast solutions (such as the ECMWF) are correct then winter weather advisories would be more likely needed as we get closer in time. Consideration was also given that this will potentially be the first widespread accumulating snowfall over the region, and the time of arrival could be just before the morning commute...potentially increasing impacts to travel etc.

After the snow breaks out late Monday night/Early Tuesday AM, the snow should become steady and even locally heavy heading into the mid and late morning hours on Tuesday...continuing through the afternoon hours. Snowfall rates could exceed 1"/hr, especially in and around the watch locations. Temperatures start off very cold early Tuesday morning, in the low to mid-20s as the snow starts. Temperatures gradually rise into the upper 20s to low or perhaps mid- 30s Tuesday afternoon. Overall, snow to liquid ratios should be high (15:1) especially across Central NY and especially Tuesday morning. SLRs may drop some, between 9-13:1 heading into the afternoon hours. This should be a dry, powdery snow for the most part in CNY, trending more average to perhaps a wetter consistency for NE PA.

The snow will quickly taper off and end from west to east late Tuesday afternoon or evening as the coastal low races north and east into the Gulf of Maine Tuesday evening. Behind the departing low a few flurries or snow showers could linger overnight, with cold overnight lows expected (in the 10s to low 20a).

Wednesday is generally dry, partly sunny and seasonable with a weak surface high sliding into the area. A strong cold front approaches the area late Wednesday night, with increasing PoPs for snow showers over north-central NY before daybreak Thursday. Overnight lows are seasonably cold, in the 20s areawide.

LONG TERM /THURSDAY THROUGH SUNDAY/

The strong cold front will be passing through the area on Thursday, bringing snow showers and perhaps snow squalls. Expect increasingly gusty NW winds as well. This will be a quick shot of colder air, with 850mb temperatures likely bottoming out around -18C or so. High pressure builds in Thursday night, and with likely fairly fresh snow cover on the ground temperatures are expected to plunge. Overnight lows are forecast to be between about 5 below and 10 above zero across the area; winds will be fairly light. Friday is likely dry, with partly cloudy and cold conditions lingering. Watching the next series of low pressure system approaching the area next weekend. A lot of uncertainty in the details at this time, but chances for snow or snow showers are in the forecast Saturday as a low tracks south of the area, and perhaps up along the coast. Temperatures start to moderate slightly by the end of the upcoming weekend, but still within a few degrees of average.

AVIATION /00Z MONDAY THROUGH FRIDAY/

A band of snow showers has tapped into a very small amount of instability over CNY and is bringing heavier than expected snow to ITH/SYR/RME. These showers and MVFR/Fuel alt restrictions should push through by 01z.

After 05z, a MVFR cloud deck should slide into CNY from the WNW, lasting into the morning. Lake effect snow showers are expected to develop across SYR and RME for a few hours tonight, with TEMPO Fuel alt conditions expected during the showers. IFR visby may be possible if a shower is heavy enough, but confidence is not high enough to include it in the TAF. VFR conditions return to the area by the late morning/early afternoon as high pressure builds in from the west.

Outlook...

Late Monday night through Tuesday...Snow and restrictions likely, potentially IFR or LIFR visibilities Tuesday morning.

Wednesday...Mainly VFR; spotty lake effect snow showers are possible around KSYR and KRME.

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

BGM WATCHES/WARNINGS/ADVISORIES

PA...Winter Storm Watch from late Monday night through Tuesday evening for PAZ038>040-043-044-047-048-072. NY...Winter Weather Advisory until 1 AM EST Monday for NYZ009. Winter Storm Watch from late Monday night through Tuesday evening for NYZ045-046-055>057-062.