Lake Ontario - Open Waters from Mexico Bay to the St Lawrence River Marine Forecast
|Tonight...Northwest Winds 5 To 10 Knots Becoming Northeast. A Chance Of Showers And Scattered Thunderstorms Early. Waves 1 Foot Or Less.|
|Wednesday...Northeast Winds 5 To 10 Knots Becoming North. Waves 1 Foot Or Less.|
|Wednesday Night...North Winds 10 Knots Or Less Becoming South. Waves 1 Foot Or Less.|
|Thursday...South Winds 5 To 15 Knots Becoming West. A Chance Of Showers In The Morning, Then Showers Likely With A Chance Of Thunderstorms In The Afternoon. Waves 2 Feet Or Less.|
|Thursday Night...Northwest Winds 10 To 15 Knots Increasing To 15 To 20 Knots. Showers Likely With A Chance Of Thunderstorms In The Evening, Then A Chance Of Showers And Thunderstorms Overnight. Waves 1 To 3 Feet Building To 2 To 4 Feet.|
|Friday...North Winds 15 To 20 Knots Becoming Northwest. A Chance Of Showers During The Day. Waves 2 To 4 Feet.|
|Saturday...West Winds 5 To 15 Knots Becoming Southwest. A Chance Of Showers Saturday Night. Waves 1 To 3 Feet.|
|Sunday...Southwest Winds 5 To 15 Knots Becoming Northwest. A Chance Of Showers. Waves 1 To 2 Feet. Winds And Waves Higher In And Near Thunderstorms.|
| Area Forecast Discussion|
National Weather Service Buffalo NY
504pm EDT Tuesday July 27 2021
A cold front will cross the eastern Great Lakes through the evening. A few storms this evening will be strong with gusty winds and heavy rain the main hazards. After showers and storms taper off later this evening, some fog and drizzle will be possible overnight through Wednesday morning. Dry weather will return for Wednesday afternoon before another cold front brings a chance of showers and thunderstorms later Wednesday night through Thursday.
Near Term - Through Wednesday
Initial line of convection earlier this afternoon moved through with little fanfare over western and north central NY. This likely was due to the greatest instability remaining well ahead of this initial line as most of the airmass across our area was impacted by outflow that pushed across the Niagara Frontier. Mid clouds have thus far held down effective instability. However, there is still a small window of time through late this evening where additional convection could develop over WNY (as already is occurring over parts of WNY) and intensify some as boundary over western LO drops southeast and interacts with lake boundary off LE. Forecasted shear and instability would support potential for isolated severe storms. Also a threat of heavy rain/localized flooding if we see storms train over same areas. Thus far we are handling with this with heads up SPS and social media messaging. Storms would be strongest through 8pm before fading with loss of daytime heating and lack of an additional strong upper level feature.
The showers and storms will taper off from northwest to southeast later this evening as the mid level trough moves east of the area. Weak north/northeast flow will develop overnight, with moisture trapped beneath a frontal inversion. This will likely set the stage for plenty of low clouds, patchy drizzle and fog overnight through Wednesday morning. The clouds, drizzle, and fog will eventually break for increasing sunshine later Wednesday as a drier airmass advects into the region.
Short Term - Wednesday Night Through Friday
Surface high pressure expands across western and north central NY Wednesday night. Dry conditions are expected. The region remains under northwest flow aloft into Thursday and two shortwave troughs will split the region. Warm air advection will occur with dewpoints climbing into the mid to upper 60s. There will likely be showers and storms to the southwest and northwest of the region early in the day. These will track eastward ahead of an approaching cold front and move into western and north central NY through Thursday afternoon. Cloud cover may impact destabilization through the afternoon so chance of severe is low at this time. The cold front will track across the region Thursday night. Much cooler air is behind this front with strong cold air advection continuing through Friday. Steepening lapse rates and a trough overhead will likely induce showers activity Friday afternoon. Temperatures at 850mb will fall to +5-6 C by Friday afternoon which may lead to lake enhanced rain showers.
Dry weather with high pressure building into the region expected Friday night. High temperatures will start off in the upper 70s to low 80s Thursday before falling to the low 70s on Friday. Low temperatures will have a similar trend, with lows in the upper 50s to low 60s Wednesday night and Thursday night before falling to the low 50s Friday night.
Long Term - Friday Night Through Tuesday
Subtle mid-level ridging place on Saturday as weak surface high pressure works in over the lower Great Lakes. Mostly dry conditions should last through Saturday evening. A closed upper level low will then quickly drop southeast out of Northern Ontario, dragging its associated cold front across the region. Shower and thunderstorm chances will increase from west to east overnight Saturday, and last through the day Sunday.
With the slow moving main trough axis still to our west, small chances for showers will linger into Monday and Tuesday. Otherwise, cooler temperatures a few degrees below climatological normals are anticipated through the long term. Daytime highs will generally settle in the upper 60s to mid 70s, with overnight lows in the 50s, some upper 40s possible on the Tug Hill.
Winds in general will remain relatively light through tonight. Scattered thunderstorms this evening may produce locally higher winds and waves. Northeast winds 10-15 knots will develop late tonight and Wednesday behind a cold front moving south of the lakes. This will produce choppy conditions Wednesday, especially along the south shore of Lake Ontario.
NOAA Buffalo NY Office: Watches - Warnings - Advisories