Marine Weather and Tide Forecast for North Rose, NY

NEAR TERM /THROUGH SUNDAY/

Strong to Severe Thunderstorms Possible Late Sunday

High pressure drifting overhead this evening with maintain clear skies. The high will shift east of the region late tonight with the pressure gradient tightening ahead of a cold front. Increasing southerly component winds late tonight should limit fog potential, although in some sheltered valley fog may still occur. Low temperatures in the 40s will likely occur by the second half of the night, before leveling out or even rising a few degrees by daybreak.

Deepening trough arrives into the eastern Great Lakes Sunday with western New York emerging into the warm sector. Robust warm air advection develops within the warm sector as a 40 to 45 knot low level jet focuses on the region, sending 850 mb temperatures to 14-15C. This will send temperatures into the lower to mid 70s for most areas, with some upper 70s possible across western New York.

A strong cold front will arrive by late afternoon with a narrow corridor of dewpoints reaching into the 60s pooling ahead of the front.
Cooling aloft along with steepening mid-level lapse rates will overlap modest boundary layer moisture to support an area of moderate instability along and just ahead of the cold front. The expectation is that a band of convection will develop along and just ahead of the cold front entering western New york around 4 PM. Strong wind fields aloft with nearly 50 knots of deep layer shear will likely yield a narrow band of organized convection. Damaging wind gusts will likely be the PRIMARY threat associated with the strong wind fields aloft. Bufkit profiles showing sufficient low-level hodograph curvature and SRH signals to suggest the potenial for supercell development with an isolated tornado possible, especially across southwest New York. SPC has much of the area in a Marginal Risk for severe thunderstorms with a Slight Risk area highlighted for southwest New York.

SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/
A sharp cold front will begin to cross Western NY early Sunday evening, with a line of showers working from west to east through the region. While there 'likely' will be some measure of thunderstorm activity, the potential for stronger storms will decrease with the loss of daytime heating. The greatest threat for stronger storms will initially be found across Western NY, then decrease the further east you go Sunday evening. Its worth noting that CAMS show 0-6km shear values up to 35 knots and instability of 850-1000 j/kg early on. With the passage of the cold front we should see shower activity quickly diminish in coverage as drier air works in across the Lower Lakes Sunday night. It will also turn much cooler as 850H fall to +1C to +2C by Monday morning. Some brief clearing may take place behind the front, but given the cool airmass spilling into the region clouds will 'likely' redevelop southeast of the lakes.
Otherwise...lows Sunday night will be found in the mid 40s to mid 50s.

Cool WNW cyclonic flow will continue to produce plenty of cloud cover Monday along with some measure of shower activity. Highs on Monday will be as much as 15F-20F degrees cooler than Sunday with 50s to low 60s across the region. Monday night lows will be found in the upper 30s to mid 40s. Given that there will be some wind flow...frost more than 'likely' will not be much of an issue. Even so...it would be wise to take precautions or atleast get prepared for frost by Tuesday night.

It definitely will feel like fall has arrived Tuesday across the forecast area. Highs on Tuesday will be found generally in the 50s, maybe a few readings around 60F. With the trough still hanging around we still can't completely eliminate the potential for a passing shower. Mainly low end chances 15%-40% with most locales seeing mainly dry weather.

LONG TERM /WEDNESDAY THROUGH SATURDAY/
An amplified pattern this week across North America, with a stout upper level ridge slowly pushing a cool, downstream trough from southern Canada/Great Lakes region out to sea.

Under this trough a mix of daytime instability showers and lake effect showers will be common Wednesday. Temperatures around 0C at 850 hPa will support the lake effect precipitation, and also keep much of the region in the 50s for daytime highs through Thursday.

As this trough and its associated moisture exits, clearing skies will allow for chilly temperatures for both Thursday and Friday mornings with increasing frost potential depending upon cloud clearing.

Surface high pressure will slide towards our region next Saturday, though the ECMWF and its ensembles maintain more of a zonal flow aloft with some cloud cover.

AVIATION /21Z SATURDAY THROUGH THURSDAY/
Surface high pressure drifting overhead and to the east tonight will bring VFR weather, with mid and high clouds increasing from the west late tonight. Light northerly winds through this evening will turn southerly tonight ahead of an approaching front.

Sunday, VFR through the morning, then mainly MVFR with local IFR Sunday afternoon through Sunday evening with showers and a chance of thunderstorms. Breezy with southerly wind gusts approaching 25-30kts at KIAG/KBUF in the afternoon.

Outlook...

Sunday night...VFR to MVFR with a chance of showers late.
Monday through Wednesday...VFR/MVFR with a chance of showers, especially east/southeast of the lakes.
Thursday...Mainly VFR.

MARINE
High pressure moving through the lower Great Lakes will maintain quiet weather on Lake Erie and Lake Ontario through tonight.

A warm front followed by a much stronger cold front will move through the region Sunday and Sunday evening respectively. South winds will increase 15-20 knots behind the initial warm front, directing much of the higher wave action offshore. The cold front will then shift winds to the west-northwest by Sunday night, likely resulting in a period of SCA conditions into Monday for Lake Erie, and Monday night for Lake Ontario.

BUF WATCHES/WARNINGS/ADVISORIES
NY...None.
MARINE...None.