Lake Ontario - Open Waters from Mexico Bay to the St Lawrence River Marine Forecast
|This Afternoon...Southwest Winds 15 To 25 Knots Becoming West. Waves 3 To 6 Feet.|
|Tonight...West Winds 15 To 25 Knots Becoming South And Diminishing To 10 To 15 Knots. Waves 3 To 6 Feet Subsiding To 1 To 3 Feet.|
|Sunday...Southeast Winds 10 To 15 Knots Increasing To 15 To 25 Knots. A Chance Of Rain In The Morning, Then Rain Likely In The Afternoon. Waves 1 To 3 Feet Building To 2 To 4 Feet.|
|Sunday Night...South Winds To 30 Knots Becoming West. Rain Showers Likely. Waves Building To 5 To 8 Feet. Waves Occasionally Around 10 Feet.|
|Monday...Northwest Gales To 35 Knots Diminishing To 30 Knots. Snow Showers Likely. Waves Further Building To 10 To 13 Feet. Waves Occasionally Around 16 Feet.|
|Tuesday...Northwest Winds 15 To 25 Knots Becoming Southwest. Waves 3 To 6 Feet Subsiding To 1 To 3 Feet.|
|Wednesday...Southwest Winds 15 To 20 Knots. Waves 1 To 3 Feet.|
| Area Forecast Discussion|
National Weather Service Buffalo NY
144pm EST Sat Feb 27 2021
Weak high pressure will pass over the region tonight...then our weather will once again turn unsettled as a storm system over the Upper Great Lakes will push a warm front through our forecast area. This will lead to several hours of rain and notably higher temperatures on Sunday...but the warmer weather will quickly give way to a rude return to winter. A pair of cold fronts will prompt the mercury to tumble to below normal levels for Monday and Tuesday.
Near Term - Through Sunday
Partial clearing late today will give way to more clouds later tonight...as a weak bubble of high pressure will move through.
Deepening low pressure tracking across the Upper Great Lakes on Sunday will push its associated warm front through our forecast area. This will support several hours of generally light rain with temperatures soaring through the 40s...and in parts of warning NY...to the lower 50s. The bulk of the afternoon will be rain free over the western counties.
Short Term - Sunday Night Through Monday Night
Low pressure across the upper Great lakes will move northeast into Quebec sending a cold front across the region early Sunday night. Colder air working in behind the boundary will eventually change any lingering precipitation over to mainly wet snow, especially across the higher terrain where some minor accumulations will be possible later Sunday night.
A quick shot of arctic air associated with a clipper system will move into the region later Monday and Monday night. Potential looking better and better for a burst of snow/line of squalls with the arctic boundary when it moves through the region sometime during the second half of Monday into Monday evening. This could very well impact the Monday afternoon/evening commute. Model consensus also continues to suggest the possibility for a period of strong winds later Monday and/or Monday night as well. If confidence continues to increase going forward, wind headlines may be needed for at least some portions of the forecast area. Some limited upslope/lake effect snow showers will then be possible east and southeast of the Lakes behind the front Monday night.
Long Term - Tuesday Through Friday
Strong high pressure will quickly build in behind the arctic front for Tuesday providing a dry, but chilly day with highs in the 20s across the majority of the region, with areas across the higher terrain east of Lake Ontario not making it out of the teens. Split (zonal) flow aloft will develop for the midweek timeframe with the northern branch of the jet residing across southern Canada, while the southern branch stays put across the southern half of the CONUS. This will keep any systems that develop to our north and/or south for Wed/Thu, keeping things mainly dry at this point with temps rising back to near or just above average.
Eastern U.S. trough will amplify toward the tail end of the work week in response to a large upper ridge building across the Rockies northward into Canada. This will likely lead to another surge of colder air for our region with the possibility for some snow showers to close out the period.
Southerly downslope winds 15 to 25 knots followed by post- frontal southwesterlies support low-end SCA (Small Craft Advisory) headlines on Lake Erie. A weak cold/occluded front will cross the waters today, resulting in brief increase in winds. With post- frontal temperatures near the lake temperature expect limited mixing, but the westerly post frontal flow will be just enough to support SCA (Small Craft Advisory) headlines for eastern portions of Lake Ontario.
Beyond the weekend, those with interests on the lakes should keep eye on Monday as there looks to be potential for high-end gales from the west across especially the waters of Lake Ontario.
There's a risk for ice jams on the Buffalo Creeks Sunday and Monday. The combination of warmer temperatures and some light rain may be enough to cause ice to break up on some of the Buffalo Creeks. Unlike earlier this week, the snowpack will be more dense (or ripe) for run-off heading into Sunday due to the warmer temperatures preceding it. Without significant rainfall, it typically takes about 300 thawing degree hours (TDH) in order for ice to start to break up on the headwaters of Buffalo Creek, Cazenovia Creek, and Cayuga Creek. At this time the latest forecast is for highs in the upper 40s/near 50 which would keep TDH below this. However, if it's any warmer than this, ice break up and associated jams will be possible. There is still a significant snow pack in place (2-4 inches in the headwaters), and ice on the creeks is thick.
This also corresponds with MMEFS ensembles which show a risk for run- off with chance for action level rises on some creeks. If it warms enough for creeks to rise to action level, there would likely be ice break up and a risk for ice jams.
NOAA Buffalo NY Office: Watches - Warnings - Advisories
Small Craft Advisory until 4pm EST this afternoon for LEZ040- 041. Small Craft Advisory until 1am EST Sunday for LOZ044- 045.