textproduct: Binghamton

WHAT HAS CHANGED

A Winter Weather Advisory was issued for Northern Oneida for the clipper system that moves today into Thursday. In addition, snowfall totals were updated for this system. Winds were also increased for most of the later half of the week as low-level flow will be strong and passing frontal systems all should lead to gusty winds. PoPs were increased for Sunday into Monday. Models have all trended the track of the low further north with what now is looking like a potentially impactful winter storm for at least portions of the region.

KEY MESSAGES

1) A clipper system will move into the region Wednesday, but weakens as it does. Snow showers will be possible across central New York with more persistent snowfall likely across northern Oneida County.

2. Frigid conditions return late this week with lake effect snow showers possible following the passage of a frontal boundary Thursday. The cold Arctic airmass will likely bring dangerous wind chill temperatures Friday night through Saturday.

3) Arctic high pressure retrogrades to the north Saturday into Sunday. Due to this shift, confidence is now increasing that portions of the area will be affected by an impactful winter storm Sunday morning through Monday morning. Although there remains quite a bit of uncertainty in the forecast details, there is potential for moderate to heavy snowfall, especially across the Twin Tiers and into the southern Catskills and Poconos Region.

DISCUSSION

KEY MESSAGE 1...

Colder air retreats today as a clipper system pushes a warm front through the region. This is a weak system, but it is likely to bring snow showers across central NY this afternoon with snow then continuing overnight. A cold front will then pass through overnight and Thursday morning. This will likely bring some lake effect snow downwind of Lake Ontario. Local terrain and lake enhancement will lead to the highest snowfall accumulations across N. Oneida. A Winter Weather Advisory was issued with snowfall totals ranging from 3 to 7 inches in the northeastern portions of the county.

KEY MESSAGE 2...

The lake effect snow will continue through at least the end of the work week and into the weekend, however with the flow at 250/260 degrees, the bulk of any lake effect will mostly remain north of our forecast area.

An Arctic cold front will bring a blast of cold air Friday, and as flow turns northwesterly, lake effect snow showers will drop south into central NY. T850 is modeled to drop as low as -25 to -28. While the start of this week was a cold one, even colder conditions are expected with wind chills of 10 to 20 below zero possible across much of the area and even colder across northern Oneida County. Cold weather headlines are likely across the entire region and a few of our northern counties could see the first extreme cold watches/warnings may be needed.

KEY MESSAGE 3...

The northward shift of a significant winter system continues with each model run. The 0Z model cycle now shows the high pressure that was offering us protection, retrograding further northward into Canada and weakening. Although considerable uncertainty remains in the overall forecast details, this type of synoptic setup is likely to bring at least advisory level snowfall into portions of our area. This system will have ample moisture with it and with the cold air mass in place, there will likely be strong frontogenical forcing along the gradient where this warm moist air plows into this arctic airmass. Where that area actually turns out to be is anyones guess at this time. However, being this system is still 4/5 days out, there remains time to be patient and wait for the models to settle on solutions as the details become more clear. Latest NBM probability for at least a warning level snowfall (6" in NEPA and 7" in NY) is now up to 40% as far north as the Southern Tier, so used this as the basis for enhanced wording in the HWO for now. Continue to monitor the forecast through the end of the week as forecast confidence will be much higher as the elements of this system start coming together.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

VFR conditions are expected to be in place through the early afternoon across the area. A warm front associated with a clipper system is expected to lift northeast across the area this afternoon that can bring some lower ceilings along with a bit of snow, mainly for RME and SYR. MVFR restrictions are possible from 19Z through about 23Z-00Z and covered for via TEMPO. After 00Z, isolated to scattered snow showers and lower ceilings are expected to linger as the clipper gradually moves east along with its associated cold front. Most of the snow shower activity will be across CNY, but drier air will also be pushing in aloft which lowers confidence in potential restrictions. RME and SYR will have the best chance of seeing additional MVFR restrictions, but it can't be ruled out at ITH and BGM as well.

Light winds this morning are expected to increase this afternoon with S to SSW gusts of 15-25 knots possible. Borderline SSWerly LLWS is expected to develop at most terminals approaching 00Z and continuing through generally 06Z-08Z.

Outlook...

Thursday...isolated to scattered snow showers possible, especially for the NY terminals.

Thursday night through Saturday...Mainly VFR, except intermittent lake effect snow showers are possible, generally for SYR-RME-ITH; low confidence on restrictions.

Sunday...Potential snow moving in; low confidence at this time in timing and track.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Winter Weather Advisory from 1 PM this afternoon to 1 PM EST Thursday for NYZ009.