textproduct: Binghamton

WHAT HAS CHANGED

Will have to watch for changes in mixed precipitation signals developing Saturday evening in our eastern zones as cold air may have difficulty retreating out of eastern NY tomorrow. Made a minor increase to wind gusts Sunday-Sunday night as unstable cold air infiltrates from the northwest. Potential for snow squalls also increasing on Sunday.

KEY MESSAGES

1) Windy into tonight with nuisance damage impacts possible from the Finger Lakes region to the Upper Mohawk Valley.

2) Rain developing again Saturday afternoon with a brief mix of wet snow or sleet possible at higher elevations of the Poconos, Western Catskills or Tug Hill at the start. Precipitation amounts look to be mainly less than one half inch. Low confidence in a changeover to icy (sleet/freezing rain) over the Catskills and Western Mohawk/Tug Hill on Saturday night.

3) Blustery conditions return Sunday into Monday with cold air and snow showers developing. The potential for dangerous snow squalls is increasing for Sunday afternoon and evening.

4) Aside from some fast moving weak weather events with little impact, generally quiet weather with no apparent hazards is expected for much of next week.

DISCUSSION

KEY MESSAGE 1...

Southerly winds will continue to gust this afternoon with occasional gusts over 40 mph likely, especially across the Finger Lakes region. A secondary surge of wind will occur along a low level jet just along and behind an approaching cold front early this evening where some enhanced and unstable flow could push 50 mph. Winds will shift west and continue to be strong and gusty for a time tonight before tapering off with building high pressure. Showers will also end this evening.

KEY MESSAGE 2...

A large low pressure system over the Western Great Lakes will affect CNY and NEPA beginning on Saturday. Complex frontal systems will sweep into the region with low pressure centers over Lake Erie and another developing over the Mid-Atlantic. Showers are expected to develop from south to north across the area during the afternoon and continue into Saturday night. With the large system to the west trading some energy off to the coastal system, we'll be caught in the middle with inclement weather, but nothing apparently hazardous as temperatures will be mainly warm enough for rain and the split system will struggle providing much rain here. Depending on exact timing, there may still be some higher elevations just cold enough for wet snowflakes or sleet before a warm wedge solidifies aloft. Probabilistic guidance is now hinting that low level cold air may struggle to exit our eastern zones depending on the strength of the developing coastal system which could spell a risk of rain changing back to icy conditions at least for a time early on Saturday night. Confidence in much impact in our area is low at this time, but it bears watching.

Then, an overnight cold frontal passage will bring much colder air aloft to the area, as 850mb temperatures fall to -10C by daybreak Sunday. Lingering precipitation will become mainly flurries with slightly better dynamics and upslope flow for minor accumulations over northern Oneida, Madison and Onondaga counties by early Sunday.

Snow has been slow to melt throughout the river basins recently and with no appreciable rainfall for the next 48 hours, only gradual rises on the rivers are expected through the weekend. Ice may move, but flooding is not anticipated.

KEY MESSAGE 3...

Steady to falling temperatures are likely Sunday afternoon as cold air advection takes hold. Model guidance has a mid level dry slot over the area in the morning with essentially no precipitation. By afternoon deep moisture wraps back into the area behind a departing low pressure system. Looking for scattered to numerous snow showers across central NY, and flurries for NEPA. A deep trough moving through, coupled with marginally mild temperatures in the 30s to start the afternoon does pose a concern for moderately unstable conditions prime for squally snow showers ahead of a reinforcing Arctic surface trough. Will need to closely monitor as we near the event. Once deeper cold air becomes established, lake snows are expected on Sunday night with nominal accumulations. Probabilistic guidance suggests a high chance for greater than 2 inches of accumulation extending over Onondaga and Madison counties and also the NW corner of Oneida county by early Monday. The same guidance also suggests that probabilities for more than 4 inches of snow are almost nil, so this again should be a fairly minor event as it is transitioning fast.

Lastly, unstable NW flow develops in the evening and overnight hours as the pressure rise couplet moves overhead in combination with a 55kt low level northwesterly jet at 850mb. This should again bring blustery winds to the region with a potential for minor impacts and additional Wind Advisories may be needed Sunday night.

KEY MESSAGE 4...

A similar complex low pressure system is forecast to affect our area on Wednesday and Thursday. Temperatures on Wednesday look marginal enough for a blend of snow and rain showers while colder air on Thursday should keep any precipitation flaky. Otherwise, the pattern is mainly northern branch dominated with no major system developments and generally quiet under transient high pressure for Tuesday and Friday.

AVIATION /03Z SATURDAY THROUGH WEDNESDAY/

With the front moving through, surface winds have picked up enough that the LLWS has lessened for most of the area. Winds shift westerly over the next several hours with MVFR cigs behind the front. High pressure builds in fast, by around 6Z. With rain at ELM, it looks like there is a chance for some fog development so added in an IFR tempo.

SW flow develops again tomorrow as another warm front lifts into the region. MVFR and locally IFR cigs will scatter out mid to late morning before MVFR cigs and rain move back in from the south after 18Z.

Outlook...

Saturday night...Restrictions likely with rain showers, mixing with snow showers late Saturday night.

Sunday...Possible restrictions with scattered rain and snow showers, especially at the Central NY terminals.

Monday through Tuesday...Mainly VFR.

Wednesday... Restrictions possible with rain and snow showers.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...None.