Lake Ontario - Mexico Bay to the Saint Lawrence River Marine Forecast
|Rest Of Today...South Winds 15 To 20 Knots Becoming Southwest. A Chance Of Waterspouts Late. A Chance Of Showers Late. Waves 3 To 5 Feet. Waves Occasionally Around 6 Feet.|
|Tonight...Southwest Winds 15 To 20 Knots Becoming South And Diminishing To 5 To 10 Knots. A Chance Of Waterspouts. Showers Likely In The Evening, Then A Chance Of Showers Overnight. Waves 3 To 5 Feet Subsiding To 1 To 3 Feet. Waves Occasionally Around 6 Feet.|
|Saturday...South Winds 5 To 15 Knots. Mostly Sunny. Waves 2 Feet Or Less.|
|Saturday Night...South Winds 5 To 10 Knots Becoming West. A Chance Of Waterspouts. A Chance Of Showers In The Evening, Then Showers Likely Overnight. Waves 1 Foot Or Less Building To 1 To 3 Feet.|
|Sunday...West Winds 10 To 15 Knots Increasing To 15 To 20 Knots. A Chance Of Waterspouts. A Chance Of Showers. Waves 2 To 4 Feet Building To 3 To 6 Feet. Waves Occasionally Around 7 Feet.|
|Monday...West Winds 5 To 15 Knots Becoming Northwest. A Chance Of Waterspouts During The Day. A Chance Of Showers During The Day. Waves 2 To 4 Feet Subsiding To 1 To 3 Feet.|
|Tuesday...North Winds 5 To 10 Knots. Partly Cloudy. Waves 2 Feet Or Less.|
| Area Forecast Discussion|
National Weather Service Buffalo NY
730pm EDT Sunday Oct 24 2021
An area of low pressure tracking toward the Great Lakes will cause periods of rain through Tuesday. Monday will feature some dry time, especially south of Lake Ontario to the Finger Lakes.
Near Term - Through Monday
Low pressure will track across northern Illinois tonight, with a sharp warm front extending east across the Ohio valley and to our region. Moist flow with PWATs (Precipitable Waters) over 1.25 inches will support moderate rain at times tonight as steady precipitation spreads from south to north along an area of warm air advection and frontogenesis in the mid-levels.
Late tonight, as shortwave trough over the Plains reaches the western Ohio Valley, H85 front will lift quickly north through western and north central NY with steady rain diminishing across the Southern Tier probably before daybreak on Monday. Rain will eventually pivot westward, so far western Niagara Frontier and the North Country may remain in some showers through most of the morning. Different story south of Lake Ontario to the Finger Lakes though as surface warm front is forecast to lift through those areas allowing any rain to cut out and surface temps to rise well into the 60s. Closer to where northeast low-level flow persists temps will be stuck in the mid to upper 50s. Any shift of the surface boundary will alter these temperature expectations so will need to keep eye on trends. Later Monday afternoon, approaching shortwave trough across the Great Lakes and large scale lift in form of differential PVA and q-vector convergence along with another surge of deeper moisture will lead to re-developing showers over western NY to the Genesee valley. Non zero chance there could be some thunder during peak heating on Monday, but instability appeared too low to include attm.
In terms of rainfall amounts, through Monday afternoon, totals will range from near a half inch over northern Jefferson county to over an inch over southern portions of Chautauqua into Cattaraugus counties. Elsewhere, totals will end up between 0.6 and 0.8 inch.
Short Term - Monday Night Through Wednesday Night
An upper level trough will move overhead Monday night. Surface low pressure over Ohio will phase with a coastal low off the Mid- atlantic coast. Moisture will wrap around this system and keep conditions cool and wet through Tuesday night.
A strong, shortwave trough will approach the region Monday night. Strong forcing and deep moisture will lead to rain, moderate at times across western and north central NY. There will be a +12C warm nose which will keep the threat for thunderstorms very low across most of the region. The exception will be towards Pennsylvania and interior New York where the warm nose weakens and some elevated instability is present. At this time, the chance for thunderstorms is too low to add to forecast. Rain will continue.nue into Tuesday as coastal low pressure deepens off the Mid-Atlantic region. This will cause DPVA and moisture to wrap around the area. Rain showers are likely during this time. Rainfall amounts up to a half inch expected across western NY and up to one inch across north central NY.
Clouds and a few showers will linger through Wednesday but a majority of the area will be dry. Clearing and dry conditions expected Wednesday night.
The spread in temperatures will be small Monday night through Tuesday night due to the rain and cloud cover. High temperatures in the mid to upper 50s, lows in the mid to upper 40s, upper 30s to low 40s Wednesday night.
Long Term - Thursday Through Sunday
A deep closed low over the mid-Mississippi Valley Thursday will slowly advance across the Northeast states through the end of this period. Thursday will be dry and mild with surface high pressure nearby, but rain will return late Thursday and into Friday...slowly advancing across our region. Greatest chances will be Friday and Friday night when an occluded front pushes north-northeastward across the CWA. Cool, near normal temperatures are expected for the later half of the forecast period with the upper level low nearby.
An area of low pressure tracking toward the area will cause a tightening pressure gradient, resulting in increased wind speeds out of the northeast over the lakes starting tonight. The increased winds have prompted the issuance of Small Craft Advisories on Lake Ontario (west of Mexico Bay) and for the Lower Niagara River. Additional small craft advisories may be needed later tonight or Monday for Lake Erie.
NOAA Buffalo NY Office: Watches - Warnings - Advisories
Small Craft Advisory from 8am Monday to 5am EDT Wednesday for LOZ043-044. Small Craft Advisory from 5am Monday to 11pm EDT Tuesday for LOZ042. Small Craft Advisory from 5am Monday to 5pm EDT Tuesday for LOZ030.