Marine Weather and Tide Forecast for Cortland, NY

KEY MESSAGES
1) A weak front will quickly move through this morning with rain showers. A stronger cold front will move through the region late tonight and Sunday morning with accumulating snowfall and much colder temperatures.

2) A system will move through the region Tuesday and Tuesday night with snow, wintry mix, and rain all possible.

3) The pattern will remain active through the rest of week as additional systems move through the area. Temperatures trend warmer through the start of next weekend.

DISCUSSION
KEY MESSAGE 1...

Southwesterly flow will keep temperatures mainly in the 30s and 40s this morning as a weak front approaches the region. This front will move in from the west just before sunrise with a narrow band of precipitation. With milder conditions in place, most will see just rain though those in N. Oneida and higher elevations along and east of I-81 could see some snow mixing in. As the front moves west to east, drier air starts to win out and the line of showers begins to dissipate. Dry conditions return as high pressure builds back in around midday. Skies will have a chance to scatter out for some sunshine this afternoon.

While temperatures will climb into the 40s and 50s today, some will see those temperatures early in the day before a cold front drops in from the north this afternoon. A disturbance will slide across the front as the boundary continues to drop south through the overnight hours. With much colder air then in place, precipitation will be all snow. Enough forcing and moisture with this system will lead to widespread snowfall accumulations ranging from 0.5 to 2 inches, all of it falling before Sunday afternoon. Behind the front, northwesterly flow over Lake Ontario will support a brief period of lake effect snow showers before high pressure builds back in.

Sunday and Monday will be significantly colder than previous days with highs in the 20s to low 30s. Overnight temperatures will range from single digits below zero to low teens. Winds will become calmer after the front passes through, though wind chills will be near or below zero late Sunday night into early Monday morning. With Monday night be slightly warmer, wind chills will be above zero for most, though still only in the single digits.

KEY MESSAGE 2...

High pressure slides out to sea early Tuesday morning as the next system approaches the Northeast. This system will bring a mix of precipitation types. Temperatures will start out below freezing Tuesday, so precipitation will be mainly snow. A warm front associated with this system will lift north and allow temperatures to warm up into the 30s, though that will likely lead to areas of rain, wintry mix, and snow during the day as a warm nose develops before surface temperatures catch up. High pressure to the north will limit the northward extent of the warm front and the track of the associated system. This and the thickness of the warm nose will determine what precipitation types are observed. Then overnight, precipitation will be mainly rain, though a few areas that will be near or below freezing may hold onto snow a bit longer.

There continues to be uncertainty with this system, mainly with the tracks and thermodynamic setup. Deterministic guidance is leaning to mainly just rain after sunset, though it will be a cold rain as temperatures will be barely above freezing in some locations.
Surface temperatures can sometimes lag behind, especially on overpasses, so additional icing may be possible if precipitation becomes just rain. Given the uncertainties, NBM guidance was favored for temperatures. Precipitation types were kept simple: rain, snow, and rain/snow mix. At this time, areas with the rain/snow mix would have the best chance for seeing a wintry mix for a period of time on Tuesday.

KEY MESSAGE 3...

Multiple systems will slide east and bring rounds of precipitation nearly each day from Wednesday through Saturday. High pressure over the Atlantic will be a driver of this as the Gulf opens up, allowing moisture to feed into these systems at times. The upside to this is that warmer air will continuously be advected into the region under south to southwesterly flow. Given this, any precipitation will be rain and temperatures trend warmer through the start of the weekend. After a wintry start to meteorological spring, a taste of spring-like conditions is on the horizon.
Unfortunately, that would increase hydro concerns as snowpack dwindles and leads to runoff.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/
A weak front is currently pushing across the area this morning resulting in some mid-level broken cloud decks, and the spotty shower activity with this boundary is not really reaching the ground, so mainly VFR conditions are expected to continue at all terminals through the afternoon. There is still a low chance of some high end MVFR ceilings briefly developing around RME and SYR as winds become westerly behind the front and tap into more moisture from Lake Ontario late this morning and early afternoon but confidence is low in this occurring. SWerly LLWS of 40 to 45 knots at 2000 feet AGL is expected to diminish between 14Z-16Z at RME, SYR and BGM.

Winds will be shifting out of the west this afternoon and evening with gusts of 15 to 25 knots and eventually become north-northwest later on tonight.

A quick-hitting round of snow will overspreading the area late tonight, generally around 07-10Z that is expected to produce MVFR and eventually some IFR conditions into Sunday morning.

Outlook:

Sunday through Sunday Night...Occasional IFR restrictions possible as snow showers move across the area from west to east during the day, followed by some light lake effect snow showers at night.

Monday through Monday Night...Mainly VFR.

Tuesday and Wednesday...Chance for rain/snow showers and associated restrictions, especially later Tuesday into Wednesday.

BGM WATCHES/WARNINGS/ADVISORIES
PA...None.
NY...None.