Marine Weather and Tide Forecast for Sackets Harbor, NY

KEY MESSAGES
1) Gusty winds are expected through this evening. Wind gusts up to 40mph are expected from the Lake Erie shoreline to the Niagara Frontier.

2) A few inches of snow are expected across the higher terrain east of Lake Ontario tonight.

3) A strong cold front will cause rain to transition to snow Wednesday. Accumulating snow is expected to begin late Wednesday across the higher terrain south of Buffalo then expand across the remainder of the region Wednesday night. Widespread snow will transition to localized lake effect snow late Wednesday night.

4) Active winter weather continues into next week with accumulating snow and frigid temperatures at times.

DISCUSSION
KEY MESSAGE 1...Gusty winds are expected through this evening. Wind gusts up to 40mph are expected from the Lake Erie shoreline to the Niagara Frontier.

An area of low pressure will move from northern Ontario to central Quebec through Wednesday. A modestly, strong low-level jet will move across the eastern Great Lakes region through tonight. Warm air advection has kept the bulk of the gusty winds aloft today, however a wind shift and weak cold air advection will support gusty winds at the surface late this afternoon through the first half of tonight.
Southwest winds 15 to 25 mph with gusts up to 30 to 40 mph are expected, with the strongest gusts along the Lake Erie shoreline to the Niagara Frontier and across the higher elevations of the Finger Lakes region.

2) KEY MESSAGE 2...A few inches of snow are expected across the higher terrain east of Lake Ontario tonight.

A warm front will move across the forecast area today, and spotty light rain or snow showers are possible. Most of this activity is not reaching the ground. An area of strong forcing ahead of a sharp shortwave trough will swing through the region tonight. This will likely provide a few hours of light rain showers late today through this evening, however this feature will pivot eastward and persist across the Eastern Lake Ontario region. Thermal profiles suggest that precipitation will be snow on the Tug Hill and western Dacks.
This would support 1-2" overnight. Rain or a mix of rain or snow is expected across lower elevations of the Tug Hill.

3)KEY MESSAGE 3... A strong cold front will result in rain showers changing to snow Wednesday. Accumulating snow is expected late Wednesday across the higher terrain south of Buffalo then across the rest of the region Wednesday night. Widespread snow will transition to localized lake effect snow late Wednesday night.

Initially, the first of two cold fronts will move across the region Wednesday. Increasing ascent from an approaching shortwave trough and increasing moisture will result in numerous rain showers across the region, with lingering snow showers across the Tug Hill.
Temperatures will begin to fall behind the cold front Wednesday afternoon into evening. During this time, a southern stream system will move north along the cold front and ahead of a deepening upper level trough. Rain showers will mix with snow showers while coverage becomes more widespread across central and north-central NY through Wednesday afternoon. Then, the arctic front will move into western NY by Wednesday evening. Steepening lapse rates and strong low-level convergence will result in lake enhancement behind the front.

There remains medium uncertainty in the coverage of snow Wednesday night. Models are struggling with the phasing of the southern system and the speed of the frontal boundary. At this time, confidence is high east of the Lakes, and a Winter Weather Advisory has been issued.

KEY MESSAGE 4...Active winter weather continues into next week with accumulating snow and frigid temperatures at times.

An anomalously deep (-1 to -3 SD) longwave trough will be well established across the CONUS east of the Mississippi Thursday. Cross- polar flow within this trough will bring a shot of arctic air across the eastern Great Lakes with 850H temps near -20C. This airmass combined with a ribbon of synoptic moisture within a vorticity maxima on the backside of the mid-level trough axis, and a very low DGZ height, will allow for a period of lake effect snow downwind of the lakes. Prevailing flow Thursday into Thursday evening will be west-northwesterly, with upstream connections directing the bulk of the snows southeast of Lake Erie and Lake Ontario, with a tertiary band 'likely' setting up across the Niagara Frontier. Models have trended notably higher with the 12z suite in regards to the latter and are reasonably consistent with one another. Would certainly not rule out advisory amounts in this area, though will hold off on additional headlines this update cycle to try and establish bit more run-to-run continuity first. Weaker bands of lake effect will be possible outside of these main areas, with most if not all locations picking up at least a fresh coating of snow by day's end Thursday.
The lake response will substantially weaken late Thursday night into Friday as inversion heights and moisture content through the column come crashing down in response to a stout thermal ridge moving overhead.

In addition to the snow, the arctic airmass combined with a fresh northwesterly breeze will lead to wind chill values near or below zero Thursday and Thursday night. Abundant cloud cover and the quick transition to southerly flow and a warm-advective pattern should preclude even colder weather, but will need to monitor how quickly any clearing is established Thursday night.

The active winter pattern is expected to continue right into next week as additional shortwave energy digs southward from the Canadian Plains, phasing with a closed low east of Hudson Bay. The deep trough encroaching on the region will direct a couple of clipper lows and associated cold fronts across the Great Lakes. These will bring opportunities for synoptic snow with embedded lake enhancement, while the gaps between systems are bridged by periods of lake effect snow. Long range guidance even suggests periods of southwest flow lake effect next week, though confidence is very low in any one model or even ensemble system at this forecast range.

Following a period of more seasonable temperatures Friday and Saturday, the frigid air will make a strong return early week. Early signs point to to the airmass behind the second aforementioned cold front being even colder than the one arriving this week, with widespread teens and single digits for highs temps.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
VFR conditions will prevail across much of the area this evening despite a passing line of rain showers. With this line however, there is a brief period of strong gusty south-southwest winds, where peak gusts of 40-45 knots were recorded across the Niagara Frontier with its passage. As this line moves east, winds will still be gusty but not as high as they were in WNY, with gusts up to 30-35kts expected. This mid-level front will pivot and persist across the eastern Lake Ontario region through tonight. Mostly rain showers are expected, with snow on the higher elevations. Flight conditions will lower to MVFR overnight as a pair of cold fronts approach the region. Increasing moisture will result in scattered showers through Wednesday morning. Showers will mix with snow by Wednesday afternoon. MVFR conditions will become IFR or below across the higher terrain Wednesday morning.

Outlook...

Wednesday.. MVFR with a mix of rain and snow showers, with IFR possible in any snow showers.

Thursday.. MVFR/IFR with localized lake enhanced snow showers possible east-southeast of the lakes.

Friday through Sunday.. MVFR with snow showers.

MARINE
Low pressure will move across northern Ontario and central Quebec through Wednesday. A southerly flow will continue to support Small Craft conditions on the Lakes. Southwest winds will increase tonight before a cold front crosses the Lakes Wednesday. Winds may diminish Wednesday morning, before increasing out of the west-northwest.
Small Craft conditions will persist trough Thursday morning, and through Thursday night across eastern Lake Ontario.

BUF WATCHES/WARNINGS/ADVISORIES
NY...Winter Weather Advisory from 11 AM Wednesday to 1 AM EST Friday for NYZ006>008-012-019-020-085.
MARINE...Small Craft Advisory until 7 AM EST Wednesday for LEZ020.
Small Craft Advisory until 11 AM EST Thursday for LEZ040- 041.
Small Craft Advisory until 7 PM EST Thursday for LOZ042-043.
Small Craft Advisory until 7 AM EST Friday for LOZ044-045.