Marine Weather and Tide Forecast for Cape Vincent, NY

NEAR TERM /THROUGH TONIGHT/
Slow moving surface low pressure centered across Lake Erie this morning will settle across the Ontario peninsula today. While this low stays put, spokes of energy will continue to rotate around this feature, supporting waves of mainly light rain to spread across the region. This being said, a band of rain from the day prior has made its way across the northern Finger Lakes and towards the eastern Lake Ontario region, and across the west a steadier band of light rain is just to the west of Western New York. Within the two bands of steadier rain, the dry air within the dry slot is eroding away evident by the numerous showers spreading northeastward across western New York and the Genesee Valley.

Today surface low remaining nearly stationary across the Ontario Peninsula. This low will gradually shift east into Western New York tonight before giving way to a coastal low heading northeastward along the Atlantic coastline. All of this said, expect periods of rain to continue through tonight. Rainfall amounts today and tonight will average between a quarter of an inch to a half of an inch. With regards to temperatures, don't expect much of a diurnal curve due to the blanket of cloud cover and rain.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/
The broad/deep mid level low will continue to make a very slow eastward progression from the Great Lakes Friday to New England Saturday, before reaching the Canadian Maritimes by Sunday morning.
Chilly, moist cyclonic flow will persist across the eastern Great Lakes through the period, supporting a continuation of a very unsettled pattern.

Rain will still be quite widespread Friday with organized forcing in the DPVA regime just ahead of the mid level circulation, and low level convergence along a well defined WNW to ESE oriented trough and axis of deformation. Overall, forcing will be a little weaker than the past few days, so expect a downward trend in rainfall amounts.

Rainfall should become more showery later Friday night through Saturday night as the best forcing and moisture move east of the area and into New England. Nonetheless, deep wrap around moisture and cool air aloft will support the likelihood of showers at times.

Temperatures will remain well below average through the period.
Highs Friday will struggle to reach the lower 50s even at lower elevations, with temperatures staying in the 40s across higher terrain. Saturday will be a few degrees warmer with less rain coverage, but still a solid 15F below average.

LONG TERM /SUNDAY THROUGH WEDNESDAY/
The very slow moving closed low will remain over the Canadian Maritimes Sunday. While the deeper moisture and forcing will have moved well east of our area, cyclonic northwest flow and another passing shortwave on the western flank of the system will still support some cloud cover and the chance of a few showers, especially in the afternoon inland from the lakes as lapse rates steepen with diurnal heating beneath the cold pool aloft.

High pressure will begin to build into the Great Lakes on Memorial Day Monday, which will be the best day of the holiday weekend with mainly dry weather outside of a spotty afternoon shower inland from the lakes. Temperatures will begin to rebound, with highs back into the 60s.

The dry weather will not last long, as another mid level closed low will take shape over the Ohio Valley and Great Lakes by the middle of next week. Model guidance begins to diverge on the timing of this system, with the slower ECMWF still offering some chance of dry weather Tuesday. Deterministic and ensemble guidance continues to suggest a likelihood of rain by Tuesday night or Wednesday as the mid level low makes a close pass over the eastern Great Lakes.

AVIATION /11Z THURSDAY THROUGH MONDAY/
A conglomeration of flight conditions this morning ranging from IFR and MVFR across Western New York Southern Tier, to VFR across the Genesee Valley and eastward due to spokes of rain rotating around a surface low over the Ontario peninsula. As the morning hours continue, expect these VFR locations to gradually deteriorate with waves of rain pivoting around the surface low.

Low pressure will remain nearly stationary just to the west of Lake Ontario today and therefore don't expect much change in flight conditions with MVFR/IFR lower terrain (MVFR east of Lake Ontario), IFR/LIFR higher terrain. Rounds of light rain will continue through the day.

Outlook...
Thursday night through Saturday.. MVFR to IFR with showers.

Sunday and Monday...Mainly VFR. A slight chance of a shower or thunderstorm.

MARINE
Low pressure will settle across the Ontario peninsula today before gradually shifting east across Western New York tonight promoting fresh to moderate easterlies across Lake Ontario and Small Craft Advisories on the western end of Lake Ontario early this morning.
Building southwesterlies this afternoon through tonight on Lake Erie will support a period of Small Craft Advisories on the eastern shores.

BUF WATCHES/WARNINGS/ADVISORIES
NY...None.
MARINE...Small Craft Advisory from 10 PM this evening to midnight EDT Friday night for LEZ040-041.
Small Craft Advisory until 11 AM EDT this morning for LOZ042-043.