Marine Weather and Tide Forecast for Mount Morris, NY

NEAR TERM /THROUGH TONIGHT/
An upper level trough is located across the Northeast and eastern Canada this morning. Low pressure over the Canadian Maritimes continues to depart to the east, while cool, northwest flow continues across the eastern Great Lakes region. Lake effect snow showers will weaken through the day as deep moisture retreats to the northeast and surface high pressure builds into the region from the south. Westerly winds will continue to weaken today. Highs will reach the low 30s across the higher terrain, to the mid 30s across the lake plains.

Off Lake Erie...A few lake effect snow showers and continue across the western Southern Tier this morning. As subsidence increases and equilibrium levels lower, snow showers will continue to weaken this morning. Little to no accmulation is expected.

Off Lake Ontario...Multiple bands of lake effect snow will continue from Wayne to far southern Oswego counties this morning. An upstream connection to Georgian Bay will support intermittent heavy snow into the Finger Lakes region. As deep moisture retreats to the northeast, snow showers will weaken through this morning. Up to two inches of additional accumulation is expected through mid-morning.

Surface high pressure will move off the east coast this evening and a southerly flow will increase overnight. A shortwave trough will become negatively tilted as it crosses the Upper Great Lakes region.
A surface low with an expansive pressure gradient will move into Lower Michigan. The nose of a 50 knot low-level jet will spread across the forecast area, and overrunning will produce a light snowfall across the region. Accumulations will be light, around an inch for majority of the area, however a slight enhancement of snowfall is expected across the far western NY and Tug Hill where one to three inches are expected. Downsloping from a southeasterly wind will limit accumulation from southern Erie county eastward into the Finger Lakes region and across the northern Tug Hill region. The southeasterly surface winds will also produce gusty winds, in particular along the Chautauqua Ridge with gusts of 30 to 40 mph.
Temperatures will rise the second half of the night.

SHORT TERM /SUNDAY THROUGH MONDAY/
An area of low pressure passing by to our west Sunday morning will push its warm frontal segment through the region. As this feature crosses the Lower Lakes it will bring a period of light synoptic snow which transitions to a rain-snow mix or plain rain as boundary layer temps warm
That said
higher terrain may still see p-type remain all snow. This will 'likely' be the case east of Lake Ontario (Tug Hill) where a Winter Weather Advisory has been issued for Lewis Co.

Otherwise...in terms of snowfall amounts look for a general 1-3", with higher terrain potentially seeing the top end of this amount.
Where a Winter Weather Advisory has been issued (Lewis Co.) there is the potential for 3-8", especially across the Tug Hill.

Wind...

As low pressure passes by the region it will then send its cold front through Sunday afternoon-evening, A tight pressure gradient and a strong 850mb LLJ (+50 knots) aloft will support wind gusts up to 50 mph within a fully mixed CAA regime. The strongest winds will be found northeast of Lake Erie and Ontario, and along the immediate lake shore.

-Lake effect...

As a colder airmass pours into the Lower Lakes and deepens Sunday evening, a brief Lake response will take place off both lakes.
Initially...a band of lake effect rain or rain-snow mix will transition over to snow northeast of lake Erie
However
it will quickly push south as wind flow veers to the west then northwest.
The same will occur off Lake Ontario Sunday night, just with a bit of a lag time behind the front
The key take away here
the bands off both the lakes quickly move south, this will limit accumulations with maybe 1-3" at best.

Any remaining lake snows will end by Monday morning as synoptic moisture depletes. High pressure builds in from the west and overhead Monday afternoon, bringing a brief period of quieter weather but chilly conditions. Temperatures for Monday behind the passing front are expected to only reach the mid 20s to low 30s for most areas, with a few low 20s possible for the higher terrain east of Lake Ontario.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
A shortwave cutting across the nations mid-section and gulf moisture will potentially work in concert to spawn a coastal low Monday night through Tuesday
However
model certainty still remains high as some guidance show the low further off the coast, but the possibility for the northwestern precipitation shield to cross the area is still present. This system exits off to our northeast Wednesday, with a brief break ahead of the next cold front which brings in a much colder airmass to the region to round out the week.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/
Lake effect snow showers will continue southeast of Lake Erie and Lake Ontario this morning. Snow showers are noticeably weakening east of Lake Erie. Heavier snow showers will continue between KROC and KFZY this morning. VFR conditions will continue outside of lake effect activity with brief periods of MVFR/IFR condition in lake effect snow showers.

Improving flight conditions across the region today. Light snow arrives from west to east late tonight. VFR conditions will become MVFR/IFR at times.

Outlook...

Sunday.. MVFR with a rain/wet snow mix. Very windy.

Monday...Mainly VFR. Local IFR in limited lake effect snow east of Lake Erie and Lake Ontario.

Tuesday...VFR/MVFR. Chance of snow showers.

Wednesday...Mainly VFR with some scattered snow showers possible.

MARINE
A deep area of low pressure over eastern Quebec will slowly move off the Atlantic coast today. Westerly winds and waves will diminish today. Small Craft Advisories will end across Lake Erie and western Lake Ontario this morning, and across eastern Lake Ontario this afternoon.

Another strong low pressure system is forecast to move across the central Great Lakes Sunday. Confidence is increasing that this will bring another round of gales to Lake Erie and Lake Ontario and therefore a Gale Watch was issued for Sunday through Sunday night.

BUF WATCHES/WARNINGS/ADVISORIES
NY...Winter Weather Advisory from 1 AM Sunday to 1 AM EST Monday for NYZ008.
MARINE...Small Craft Advisory until 10 AM EST this morning for LEZ040- 041.
Gale Watch from Sunday morning through late Sunday night for LEZ040-041.
Small Craft Advisory until 10 AM EST this morning for LOZ042.
Gale Watch from Sunday morning through Monday morning for LOZ042>045-062>065.
Small Craft Advisory until 4 PM EST this afternoon for LOZ043>045.