Lake Ontario - Open Waters from the Niagara River to Hamlin Beach Marine Forecast
|Tonight...West Winds 20 To 25 Knots. A Chance Of Rain Showers Late This Evening. A Chance Of Rain And Snow Showers After Midnight. Waves 5 To 8 Feet. Waves Occasionally Around 10 Feet.|
|Friday...West Winds 15 To 25 Knots. A Chance Of Snow Showers Through Early Afternoon. Waves 4 To 7 Feet. Waves Occasionally Around 9 Feet.|
|Friday Night...Northwest Winds 15 To 25 Knots. A Chance Of Snow Showers. Waves 4 To 7 Feet Subsiding To 3 To 6 Feet. Waves Occasionally Around 9 Feet.|
|Saturday...Northwest Winds 15 To 20 Knots. A Chance Of Snow Showers. Waves 3 To 6 Feet.|
|Saturday Night...Northwest Winds 15 To 20 Knots Diminishing To 10 To 15 Knots. Waves 3 To 6 Feet.|
|Sunday...Northwest Winds 5 To 15 Knots Becoming Northeast. Waves 2 To 4 Feet Subsiding To 1 To 2 Feet.|
|Monday...Northeast Winds 10 To 15 Knots. A Chance Of Snow Showers. Waves 2 To 3 Feet.|
|Tuesday...Northeast Winds 10 To 15 Knots Becoming Northwest. A Chance Of Snow Showers During The Day. Waves 2 To 3 Feet.|
| Area Forecast Discussion|
National Weather Service Buffalo NY
317pm EST Thu Jan 21 2021
Light snow tied to warm front starting to transition to lake enhanced snow east of Lake Ontario into this evening. After brief warming today, a cold front will bring another shot of cold air to the area later tonight into Friday, resulting in another round of accumulating lake snows east of both lakes into Saturday, most significant for the higher terrain east of Lake Ontario.
Near Term - Through Friday Night
Regional radar shows most snow is occurring over the North Country and over north central NY along advancing warm front. Still quiet over rest of forecast area though it remains breezy closer to Lake Erie and across western Niagara Frontier with wind gusts 30-40 mph at times. Regional radar quiet back over most Michigan suggesting that with similar temps sfc-aloft per observations and 12z soundings from BUF, Detroit and Gaylord MI
, we'll stay fairly status quo for rest of the afternoon.
Leading edge of colder air, at least aloft tied to secondary shortwave, is over northern Lower Michigan and moderate snow is occurring there. This colder air aloft and shortwave will work over our region later this evening while 992mb surface low south of James Bay slides across southern Quebec this evening. In the meantime, there will be just enough forcing/moisture/instability from the lead shortwave crossing Quebec and west-southwest flow across Lake Ontario to result in light to moderate snow into the Tug Hill Plateau region. Heaviest snow in this area, currently under a Lake Effect Snow Warning, will not develop til later this evening.
Later this evening and overnight, temps aloft gradually get colder as flow becomes more westerly and eventually northwesterly late. The addition of the cooler air aloft (-9C at 850mb) will support a lake response off of both lakes with better more focused band off of Lake Ontario, due to the stronger low-level convergence across the Tug Hill. Forecast soundings show sufficient moisture and lake equilibrium levels to around 8kft for Lake Erie and 13kft for Lake Ontario. Strongest, most focused lake effect will be east of Lake Ontario while more transient lake effect will occur east of Lake Erie. Total snow amounts tonight east of Lake Ontario over the Tug Hill could still reach over 10 inches. Lower elevations will see more in the 1-4 inch range. Cannot rule out advisory being needed east of Lake Erie but qpf/snow will have to come up a bit more for that. Also right now any additional factors such as blowing snow don't look as significant.
Arctic front currently dropping across Lake Superior arrives over western NY Friday morning. Once the arctic front moves through on Friday morning, lake effect bands on westerly flow will shift south along the southern shore of Lake Ontario and western Southern Tier and really a spray of snow showers with lower vsby at times/possible snow squalls could develop across rest of the area as well as H85 temps fall to around -15c by Friday evening. The mobile nature of the lake bands off of both lakes with the passing front will limit snowfall amounts for any one location. However, one thing that continues to show up in the high res guidance is potential for dominant streamer band originating off the wide open waters of eastern Lake Superior and crossing Lake Huron as well. In general, snow amounts of 2-4 inches will be possible for Friday with the lake bands. However, could see several inches at least locally if the bands and especially the stronger band with upstream connections stays put for longer period of time. This will be something to watch especially to the south and southeast of Lake Ontario later Friday afternoon into Friday night as the lake effect snow showers continue over much of the area.
Short Term - Saturday Through Sunday Night
Main upper level trough axis will cross the area by midday Saturday, with a cold, gusty northwest flow continuing to produce lake snows southeast of both Lakes through Saturday morning. Some additional minor accumulations will be possible before drier air and subsidence associated with ridging surface and aloft builds across the area from the west Saturday afternoon in the wake of the trough axis passage. That said, would still expect some light lake effect snow showers to continue southeast of the lakes into Saturday evening.
Outside of a few lingering light snow showers southeast of the Lakes during the first half of Saturday night, high pressure will keep dry weather around for Saturday night and Sunday. Some moisture will try to move into western NY Sunday night, however it appears conditions will remain dry.
Otherwise, expect a cold weekend with below normal temperatures. Highs Saturday will range mainly through the teens, with some low 20s across the lake plains. It will be a bit warmer on Sunday with generally 20s found south of Lake Ontario and teens hanging on east of Lake Ontario. Saturday night lows will range from the upper single digits to mid teens south of Lake Ontario, to possibly below zero across the North Country.
Long Term - Monday Through Thursday
An approaching mid level trough and associated surface cyclone will bring steadily increasing chances for snow showers for Monday. There is still uncertainty concerning the track of a low pressure system Monday night and Tuesday as latest 12z model guidance continues to diverge. The 12z ECMWF (European Centre for Medium-Range Weather Forecasts) is the furthest north with this system, overspreading most of the area with precip, while the latest GFS keeps it just to the south of our area. The Canadian NH continues to alternate between a more southerly or more northerly track, with the latest 12z run now indicating the latter but still keeping much of the North Country dry. Forecast uses a blend of model guidance with a chance of snow from this system, the higher chances for snow being over the Southern Tier. Added some slightly higher Probability of Precipitation south of Lake Ontario for Monday afternoon as marginal 850mb temperatures and northeast flow may lead to some lake enhancement. Whether this comes to fruition or not will depend on the track of the low and how far north its warm frontal boundary is able to push.
Precip chances for the area will gradually decrease overnight Monday through Tuesday as the low continues moving east. Colder air filtering in on a NNW flow and marginal 850mb temps may lead to a few light lake effect showers south of Lake Ontario Tuesday night and Wednesday. A shortwave trough then approaches the area Wednesday night, which looks to potentially impact the area for Thursday.
Highs through the period will average in the mid to upper 20s for most of the area, with lows in the mid to upper teens and single digits east of Lake Ontario.
Fresh to strong southwest winds shift to the northwest on Friday. Small Craft Advisories continue through Friday for the prolonged period of stronger winds. Possible that eventually the Lower Niagara River may need to be placed into a new Small Craft Advisory as winds become more northwest resulting in higher waves toward the mouth of the river.
NOAA Buffalo NY Office: Watches - Warnings - Advisories
NY...Lake Effect Snow Warning until 1pm EST Friday for NYZ006>008.
Small Craft Advisory until 7pm EST Friday for LEZ040-041. Small Craft Advisory until 1am EST Friday for LEZ020. Small Craft Advisory until 7pm EST Friday for LOZ042>045.