Marine Weather and Tide Forecast for Mansfield, OH

NEAR TERM /THROUGH TUESDAY NIGHT/
Headline changes made today: *Issued Winter Weather Advisory for Lake, Geauga, Ashtabula, and Crawford PA counties for Tuesday morning through Wednesday morning/afternoon. End time varies depending on county.
*Lake Effect Snow Warning for Erie, PA remains unchanged.

Lake effect clouds have been eroding more than expecting from the south as a high pressure ridge and associated dry air expands from the south. A good chunk of the forecast area is actually under sunny skies (except Northwest Pennsylvania...sorry!)...Good time to catch up on that vitamin D!

Colder air aloft should filter in with westerly flow, allowing for inversion heights to gradually deepen this evening through tonight, with moderate lake-induced instability developed by Tuesday morning.
Already starting to starting to see better returns on radar reflectivity over Lake Erie the past hour or so as those colder temperatures move in. Warmer Lake Erie temperatures and the development of a single primary snow band should result in a lake- aggregate surface trough. This should push the snow band a bit farther north, primarily impacting Erie, PA this evening through tonight, with about 1-3" of snowfall accumulation. Most of this should be in the northeast part of the county. Outside of the lake effect snow, temperatures and wind will combine for fairly chilly conditions as wind chills down to near -5 are expected late tonight into early Tuesday morning.

Meanwhile, an upper-level trough builds in from the northwest, crossing the Great Lakes region tonight and the local forecast area during the day Tuesday. This is when we will have the coldest air aloft, deepest inversion heights, and greatest lake-induced instability. Lake effect snow is expected to gradually intensify Tuesday morning as it snows over Lake Erie and mainly Erie, PA before it guided inland by the upper-level trough, affecting much the typical snow belt region in Northeast Ohio and Northwest Pennsylvania. The best snowfall accumulations are expected Tuesday afternoon into Tuesday evening when 2-4" of snow should fall across the entire snow belt, with locally higher amounts. Snowfall rates of around 1"/hr will be possible.
Windy conditions may also produce blowing and drifting of snow, especially for locations within a few miles of Lake Erie where wind gusts of up to 35 mph is possible. Outside the snow belt, should see brief areawide snow showers Tuesday afternoon/evening associated with the upper- level trough and surface trough.
Latest model- guidance has trended towards more favorable conditions for snow squalls with this system as it shows a solid pressure change couplet with the front, high low-level lapse rates, and moderate low- level CAPE. Modeled reflectivity from CAMs also looks "squally", especially after 18Z Tuesday. While snowfall accumulations (outside the snowbelt) are expected to be an inch or less, these snow squalls can produce significant impacts due to cold air and road temperatures and the short duration in which snow falls within snow squalls.

As the upper-level trough departs to the east Tuesday night, should see a brief decline in snow showers early Tuesday night before low-level moisture associated with upstream Great Lakes builds back in later Tuesday night. Snowfall rates will be quite a bit less than what we see Tuesday afternoon/evening. It will be another chilly night with wind chills down into the low single digits or just below zero.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/
Winter Weather Advisories and the Lake Effect Snow Warning continues into Wednesday for all but Geauga County. Northwest flow aloft continues as surface winds start to back ahead of high pressure building into the Ohio Valley. The moisture depth will become increasingly shallow, especially as any moisture contribution from Lake Huron shifts east of the area but given the dendritic growth zone focused in the lowest 5K feet expect snow to continue. The snows will tend to be light to moderate but could see some enhancement and even potentially a more west to east band where low level convergence in maximized ahead of the building high. The backing flow may even allow some moisture contribution from Lake Michigan to move across Lake Erie and enhance snows for a period of time. The snow is expected to become focused more to the north with time which is why the Advisory for Geauga County does not go as long. Given the continued cold conditions, snow ratios will be efficient at near or over 20:1.

Some sun is expected on Wednesday as high pressure builds in from the south. The clearing and light winds early on will allow temperatures to drop quickly Wednesday night and northwest Ohio may achieve overnight lows before midnight then warm as southwesterly winds and warm advection increase late. Many inland areas will see wind chills drop below zero again on Wednesday night while actual lows range from about 5 to 15 degrees.

Another upper level trough dives south out of Canada on Wednesday night with low pressure passing near James Bay. A narrow ribbon of moisture with isentropic ascent develops late Wednesday night into Thursday AM with light snow expanding Thursday afternoon especially across NE Ohio and NW Pennsylvania. Light accumulations of up to 2 inches are possible in NE Ohio with 1-3 inches in NW Pennsylvania through Thursday night.

LONG TERM /FRIDAY THROUGH MONDAY/
The long term starts with brief ridging and temperatures warming to near normal values in the mid 30s on Friday and Saturday. Skies will be partly cloudy on Friday but increasing southwesterly winds will keep wind chill values in the 20s. As low pressure passes north of the Great Lakes on Friday night, precipitation will blossom across the Ohio Valley and spread northeast. Temperatures are expected to dip into the lower 30s as precipitation develops so either a cold rain or rain/snow mix is the most likely precipitation type at this time. Models are not depicting a warm nose aloft so it looks like a smooth transition to either rain or snow without other mixed precipitation types at this time.

The next cold front arrives behind this system on Sunday with temperatures trending much colder for the start of next week. Sunday will be a transition day before the arctic air arrives Monday into Tuesday. Long range models do show some spread with regards to the evolution of what will likely be a broad and deep upper level trough swinging south out of Canada. Nearly all long range models show 850mb temperatures of -20 to -25 but not at the same time. This looks to bring very cold temperatures to the area during the Monday to Wednesday time frame. We will also be monitoring for another round of light snow Sunday night into Monday as low pressure tracks up the east side of the Appalachians.

AVIATION /18Z Monday THROUGH Saturday/
Current observations show lake effect clouds streaming into parts of Northwest Ohio off of Lake Michigan as well as in Northeast Ohio and Northwest Pennsylvania off of Lake Erie. High pressure is located well to the southwest but a high pressure ridge extending from this into Ohio has resulted in far more clearing of cloud cover than previously expected. This is mainly in central Ohio but has even extended farther north to parts of the Lake Erie shoreline between Cleveland and Toledo. Wherever clear skies have developed should last through at least the daytime hours today before it fills back in tonight. Ceilings have been pretty consistent in the 2000-3000 ft range.

Meanwhile, lake effect snow persists primarily over Lake Erie but may clip some of the Lake Erie shoreline, especially in Northwest Pennsylvania (including KERI). Put a prevailing 3SM snow in the TAF but more than likely it will be varying between no snow and visibility lower than 3SM as the snow band wavers.

A low pressure system moves across the northern Great Lakes on Tuesday with a trough moving south across the area during the late morning to early afternoon hours. Should see at least areawide snow showers develop during the early afternoon hours, though more noticeable impacts may not be until after 18Z. Heavy snow may begin to move into the snowbelt region of Northeast Ohio and Northwest Pennsylvania during the time period, where visibility will likely drop to 1/2 SM or lower at times with snow rates of 1"/hr at times. KERI will be the primary TAF site affected by this before 18Z.

Breezy west winds continue this afternoon with gusts as high as 20 to 25 knots. These winds settle down tonight though sustained winds of ~10 knots still expected. They pick back up Tuesday afternoon with gusts of 20 to 25 knots once again expected.

Outlook...Non-VFR in lake effect snow will continue through Thursday across the snow belt of Northeast Ohio and Northwest Pennsylvania. Non-VFR is possible with rain and snow areawide Friday night into Saturday.

MARINE
Another push of cold air will arrive across Lake Erie overnight through Tuesday morning with the arrival of an arctic cold front.
West southwest winds of 20-30 knots continue through Tuesday morning then shift to the northwest as a trough over the lake pushes inland.
Small Craft Advisories extend into Wednesday and may need to go longer as unsettled conditions continue through the week. Ice continues to grow and Small Craft Advisories are no longer being issued west of Vermilion due to the ice coverage.

The elevated wind conditions are also resulting in occasional low water levels on the western basin. Water levels are expected to be a concern through Tuesday morning until the wind shifts to more northwesterly.

Some freezing spray is possible this week, mainly on Tuesday when the coldest air will be over the region. Flow being primarily down the long fetch of the lake though is allowing the warmer water to modify the temperatures and keep temperatures generally in the lower 20s. Would like to see temperatures a little colder before heavy freezing spray becomes a concern.

Winds back to southwesterly on Wednesday as high pressure builds into the Ohio Valley. Any decrease in winds will be brief as southwesterly winds ramp up again on Wednesday night into the 15-30 knot range ahead of low pressure crossing Ontario. High pressure builds into the Ohio Valley again on Friday.

CLE WATCHES/WARNINGS/ADVISORIES
OH...Winter Weather Advisory from 8 AM Tuesday to 4 PM EST Wednesday for OHZ012-014-089.
Winter Weather Advisory from 10 AM Tuesday to 10 AM EST Wednesday for OHZ013.
PA...Lake Effect Snow Warning from 1 AM Tuesday to 1 AM EST Thursday for PAZ001-002.
Winter Weather Advisory from 10 AM Tuesday to 4 PM EST Wednesday for PAZ003.
MARINE...Low Water Advisory until 1 PM EST Tuesday for LEZ142>144- 162>164.
Small Craft Advisory until 7 AM EST Wednesday for LEZ145-146.
Small Craft Advisory until 7 PM EST Wednesday for LEZ147>149.