textproduct: Binghamton

SYNOPSIS

Quiet start early today before rain moves in later this morning. Mild temperatures hold through Wednesday, then a cold front Wednesday night brings colder air, areas of heavy lake effect snow, and increasing winds into the Thanksgiving weekend.

NEAR TERM /THROUGH WEDNESDAY NIGHT/

A low pressure system tracking over the midwest will gradually bring showers into the region ahead of a warm front. Showers are expected to move in by late this morning/early afternoon from southwest to northeast. Warm air advection will keep temperatures mild for late November with highs climbing into the upper 40s to low 50s. Rainfall amounts will be about a quarter inch with this system by evening. Overnight the temperatures will remain warm, with lows only in the upper 30s to low 40s.

Dry slot will be over the area Wednesday morning into the early afternoon however, shower chances will increase later in the day ahead of an approaching cold front. Temperatures ahead of the front will be well above average with highs in the upper 50s to low 60s. Rain chances ramp up from west to east by the afternoon, along with increasing winds. Front pushes through the area Wednesday evening into Wednesday night with strong cold air advection behind it. Temperatures overnight will fall into the upper 20s to low 30s. Therefore any lingering showers may transition to snow especially over higher elevations.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/

A non diurnal trend is expected on Thursday as colder air continues to filter in. By early Thursday morning 850 mb temperatures fall to -9C as upper level trough swings into the region. Lake temperatures are around +10C creating a large temperatures difference. This will result in a very favorable set up for lake effect snow showers with plenty of instability. This set up is expected to be a long duration event lasting into Saturday with fluctuations in wind direction off of the lakes. Initially southwesterly flow will keep most showers north and west of our area on Thursday. Although some showers coming off of Lake Erie may clip western and northern portions of our forecast area. At this time, any snow accumulations on Thursday are expected to be minor, less than half an inch. Temperatures on Thursday are colder, with highs in the 30s and west winds increasing between 15-25 mph with gusts up to 30-40 mph possible.

It is not until the trough axis moves through Thursday night into Friday that winds shift west-northwest. Lake effect effect bands are more likely to become organized over the northern portion of our area during this time period. Model soundings show plenty of lift and saturation through the DGZ. With persistent west-northwest flow and deep moisture in place lake effect snow continues all day Friday and likely through Friday night. Watch remains in effect with no upgrades at this time as there is uncertainty in where exactly bands will set up. Snowfall amounts will be highly dependent on wear the bands set up and for how long. Regardless several inches of snow accumulation may be possible over our very northern counties. Another hazard to note with this event are the strong winds expected. Gusts as high as 40 mph will be possible and this will cause drifting of snow and possibly whiteout conditions in exposed open areas.

LONG TERM /SATURDAY THROUGH MONDAY/

Lake effect snow showers may linger into Saturday before weak high pressure builds south of the region. Flow shifts back to the southwest cutting off any lingering showers. Despite this temperatures remain cold Saturday and Saturday night. Greater uncertainty enters the forecast for Sunday into next Monday, as some warm air advection showers are possible out ahead of a large weather system that slides east across the southern US. For now, will stick with NBM PoPs for that period due to the great uncertainty.

AVIATION /08Z TUESDAY THROUGH SATURDAY/

Conditions will be VFR for just over half of the TAF period. A system will move into the region tomorrow afternoon and bring widespread rain showers to all terminals. In addition, ceilings will quickly fall from MVFR/Fuel Alt to IFR/LIFR. Visibilities will also be reduced as localized showers will be moderate to heavy at times. Shower chances then decrease after 00z Wednesday though most terminals will remain in the IFR/LIFR category due to low ceilings. Some lingering showers cannot be ruled out at SYR and RME.

South to southeasterly winds will be light until around 12 to 14z. Then southerly winds will become more gusty as they system approaches with peak gusts between 15 and 20 kts in the afternoon. While winds will become calmer at RME and SYR, the gusts will likely remain at the rest of the terminals heading into the overnight hours.

A low-level jet across Central NY will result in low-level wind shear (LLWS) at all terminals except AVP. Conditions look more borderline at SYR and RME but LLWS was left in the TAFs. LLWS diminishes around the same time surface winds pick up later this morning. Another period of LLWS is then expected at AVP by around 20z. SYR is the only other terminal where wind shear is expected late today.

Outlook...

Wednesday...Chance for rain showers and associated restrictions.

Thursday into Saturday...Cold front brings Lake Effect snow showers and associated restrictions. Best chance for IFR is currently at ITH/SYR/RME.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Winter Storm Watch from Thursday afternoon through Saturday morning for NYZ009-018-036-037.