Marine Weather and Tide Forecast for Olcott, NY

KEY MESSAGES
1) Lake enhanced and upslope snows will focus east and east- southeast of the lakes into this evening, before shifting south and southeast of the lakes later tonight into Thursday.

2) Low pressure sliding across Quebec Province may bring some accumulating light snow from late Friday into Saturday...with the best chances for this east of Lake Ontario.

DISCUSSION
KEY MESSAGE 1...Lake enhanced and upslope snows will focus east and east-southeast of the lakes into this evening, before shifting south and southeast of the lakes later tonight into Thursday.

Cold, moist cyclonic flow aloft combined with 850mb temps in the negative low to mid teens C will keep lake enhanced and upslope snow showers going east and southeast of the lakes tonight into Thursday.
A secondary cold front will drop across the area late this afternoon into this evening causing westerly low level flow to veer northwest for tonight and Thursday. This will allow lake enhanced and upslope snow showers east of Lake Ontario to gradually taper off through the overnight, however lake enhanced and upslope snow showers will continue south of Lake Ontario and south/southeast of Lake Erie through Thursday morning before tapering off Thursday afternoon as mid level moisture is stripped away and equilibrium levels lower.

Expecting an additional 2-5 inches across east of Lake Ontario through the early overnight, before tapering off as low level flow shifts northwest, thus a Winter Weather Advisory remains in effect through 1 AM tonight. Expecting an additional 2-5 inches across Wayne and N. Cayuga County where a Winter Weather Advisory remains in effect through 1 PM Thursday, with 1-4 inches across remaining areas south of Lake Ontario and east of Lake Erie, but over a longer period of time through midday/afternoon Thursday. The higher-end amounts will be across lake enhanced and upslope areas.

KEY MESSAGE 2...Low pressure sliding across Quebec Province may bring some accumulating light snow from late Friday into Saturday...with the best chances for this east of Lake Ontario.

Between later Friday and the first part of Saturday a fast-moving shortwave trough will slide across southwestern Quebec and New England...while broad/weak low pressure pivots across Quebec Province. The increase in synoptic-scale lift and moisture attendant to these features will bring the opportunity for another quick shot of accumulating light snow to the area during the above time frame.
The greatest potential for this will be found east of Lake Ontario which will lie directly in the path of the aforementioned shortwave and consequently where moisture will be deepest and lift maximized...with this and some upsloping possibly resulting in some 1-3"/2-4" accumulations across the lower elevations/higher terrain respectively. West of this snow probabilities and amounts should generally tend to drop off with increasing southwestward extent...though uncertainty still persists in exactly where the western edge of the precip will lie
With this in mind
have kept a range of chance PoPs in place across western New York for now.

Regardless of how much snow we do see from this system...there is fairly good agreement that this should taper off between the latter half of Friday night and Saturday morning...leaving behind mainly dry weather for Saturday afternoon.

AVIATION /00Z THURSDAY THROUGH MONDAY/
For the 00Z TAFS plumes of IFR and lower lake effect snow showers continue to the southeast of the Lakes this evening. Winds will continue to veer to the northwest as a secondary surface trough drops across the TAF region this evening, and this should return KART to VFR, while the 4 TAF sites south of Lake Ontario continue with varying intensity lake effect and upslope snow showers.
Greatest duration of IFR and lower flight categories are expected south of Lake Ontario, including KROC.

As moisture begins to wane tomorrow we should see an improvement with lake effect snow diminishing and VFR becoming more predominate through the late morning and afternoon hours. To close out the TAF cycle a few lake effect and upslope light snow showers and flurries may linger near KJHW.

Outlook...

Thursday night...Improving to VFR.

Friday and Saturday...Mainly VFR, but restrictions possible in snow showers late Friday and early Saturday, especially east of Lake Ontario.

Sunday and Monday...Mainly VFR.

MARINE
A secondary cold front will cross the Lower Great Lakes this evening with fresh west winds veering to northwest. Small craft headlines remain in place on both lakes as outlined below. Winds will gradually weaken through tonight into Thursday morning as the gradient relaxes across the region. The next chance for small craft conditions will arrive for Friday afternoon into Saturday morning as a clipper low dives south toward the lakes.

Please note...Most, if not all of the Lake Erie nearshore waters are now ice covered. Waves have been omitted from the forecast.

BUF WATCHES/WARNINGS/ADVISORIES
NY...Winter Weather Advisory until 1 PM EST Thursday for NYZ004-005.
Winter Weather Advisory until 1 AM EST Thursday for NYZ006>008.
MARINE...Small Craft Advisory until 1 AM EST Thursday for LEZ040-041.
Small Craft Advisory until 4 AM EST Thursday for LOZ042.
Small Craft Advisory until 7 AM EST Thursday for LOZ043- 044.