textproduct: Binghamton

WHAT HAS CHANGED

No major changes with this forecast update. The Thursday system continues to trend further south and misses our area.

KEY MESSAGES

1) A clipper system through the Northeast late tonight through the day Wednesday with accumulating snow. This will be followed by lake effect snow generally north of the I90 corridor through Thursday.

2) Widely varying temperatures this weekend with warm conditions Saturday, followed by below average temperatures for Sunday and the start of Meteorological Spring.

DISCUSSION

KEY MESSAGE 1...

A fast hitting clipper system will impact the region tonight into Wednesday. This system will first push a warm front through the region overnight with a nondiurnal temperature trend with lows occurring around midnight in the low to mid teens before climbing to the mid 20s by daybreak. Isentropic lift will produce widespread accumulating snow from just after midnight through daybreak, with widespread 1-3 inches of snow and localized amounts up to 4 inches possible across portions Central NY. With the widepsread amounts remaining below advisory criteria, an advisory will not be further expanded. Northern Oneida County will remain in an advisory due to a quick burst of 2-4 inches with the clipper system and additional lake effect snow expected behind this system.

Temperatures will continue to climb through the day, reaching the mid to upper 30s for most, with some low 40s in the valleys of the Southern Tier and NEPA. As the cold front pushes through later in the afternoon, forecast soundings are showing some instability with about 100 J/kg of CAPE. Although temperatures will be warm at the surface, temperatures will start to cool aloft in the afternoon as the axis of the upper trough drops southward and precipitation will likely fall as snow or snow pellets. It is possible that some snow squalls develop or at least some convectively driven snow showers during the afternoon ahead of the cold front. Synoptic winds luckily look to be light, but they could be gusty within the heavier showers. Forecast soundings also show some drier air in the lower atmosphere and this will allow wet bulbing to quickly cool surface temperatures under the snow showers. However, with the warm surface temperatures and late Feb sun angle, accumulations for most areas will be very light and minimal impacts to travel is expected.

Behind the cold front, lake effect snow showers are expected to develop tomorrow night and persist into Thursday across the Mohawk Valley and north into the Tug Hill region as westerly winds will prevail off Lake Ontario. All in all, 4 to 8 inches of snow is possible across Northern Oneida County with localized amounts up to 9 inches through Thursday morning and a Winter Weather Advisory remains in effect there from 1am Wed to 7am Thurs.

KEY MESSAGE 2...

All of the major models have trended further south with the system on Thursday as surface high pressure takes control over the Northeast U.S. This will keep any measurable precipitation with this system well south of the region with just a small chance for a flurry into the Poconos.

High pressure for the end of the week and rising heights on Saturday with SW return flow will advect warm air into the region. Most of the forecast area has forecast highs in the mid to upper 40s and valleys pushing 50 degrees.

However, this is the time of year where we can see significant shifts from day to day and a strong cold front is forecast to push into the area overnight into Sunday. Strong cold air advection on NW flow returns on Sunday. Highs only top out in the mid to upper 20s for CNY with some low 30s in NEPA. Sunday night into Monday will see a return of single digit lows across much of the area, with N Oneida possibly falling below 0.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

Mainly clear skies and widespread VFR conditions will persist this evening across the area. High clouds will race in from the west by late evening, gradually lowering to a mid level cloud deck close to midnight LST (05z).

VFR will be relatively brief as a clipper moving in tonight is expected to lead to IFR or worse conditions starting between 05-08Z at all taf sites. Some borderline SSWerly LLWS is also possible as the snow develops at most sites, mainly in the predawn hours. The IFR snow last several hours before exiting west to east between 12-14z Wednesday morning. MVFR CIGs linger much of the day on Wednesday, but it could scatter out into the afternoon hours. Convective snow and rain showers develop late in the day and evening hours Wednesday with associated visibility restrictions possible.

South winds increase overnight 8-15 kts, with gusts around 20 kts expected. Winds turn westerly Wednesday afternoon and remain breezy to gusty, 10-20 kts.

Outlook...

Late Wednesday Night - Thursday morning...Mainly VFR; there can be some scattered lake effect snow showers around SYR/RME. Confidence moderate.

Thursday afternoon and night...Scattered lake effect MVFR clouds may persist for some locations. Confidence moderate.

Friday and Saturday...Mainly VFR. Confidence moderate to high.

Sunday...Restrictions possible as cold front moves through the region with snow showers.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Winter Weather Advisory from 1 AM Wednesday to 7 AM EST Thursday for NYZ009.