textproduct: Binghamton

WHAT HAS CHANGED

Temperatures were lowered tonight with skies clearing out. A wintry mix of precipitation types was added for a system that moves through on Tuesday.

KEY MESSAGES

1) Today will be much colder and snow showers move through the region this morning with a widespread coating to 2 inches of snow by the afternoon.

2) The next system Tuesday and Tuesday night will bring snow, wintry mix, and rain.

3) Temperatures trend warmer the rest of the week but the pattern will remain active with multiple chances for rain. The potential for ice jams and flooding increases toward the end of the week.

DISCUSSION

KEY MESSAGE 1...

The expected band of snow showers has entered the region, though some areas are too dry for there to be much if anything to hit the ground. The weak disturbance will move through the region this morning with widespread light snow showers. Mesoanalysis and models are showing some FGEN banding at 700mb that line up fairly close to the current activity as well as expected snowfall. This could locally enhance snowfall amounts, mainly across central NY as the FGEN band weakens as it drops south. Seeing this, QPF was increased with the help of HREF guidance. Localized amounts up to 2 inches will be possible in central NY but for most, an inch or less is expected.

Behind this band of snow, northwest flow will support lake effect snow showers. In general, the set up is fairly weak and snow will be light if not just flurries. A couple additional tenths of snow are expected within the lake effect which be isolated to the Finger Lakes for most of the morning and early afternoon. High pressure builds into the region during the afternoon hours and should cut off any remaining lake effect snow. Guidance is showing lake effect potentially redeveloping tonight for localized areas in central NY but confidence was not high to include in the forecast as it looks to be flurries at best.

Temperatures will be significant colder today as a colder airmass continues to filter into the region. Highs will range from the upper teens in the Tug Hill to mid 30s in the Wyoming Valley. With skies clearing out, it should lead to efficient radiational cooling, so this forecast favored a blend of NBM 50th and NBM 10th percentiles. That adjustment gave lows in the single digits for most, but sub-zero lows in much of Oneida County. The one uncertainty is that guidance has some lake clouds potentially lingering over the Finger Lakes for the first half of the overnight hours, and that could keep those areas slightly warmer than forecasted. While winds will be fairly light, wind chills will range from -10 to 10 deg F. Monday will be sunny but cold with temperatures once again in the 20s and 30s. Overnight lows will be in the teens and 20s. With warmer temperatures, wind chills are expected to remain above zero.

KEY MESSAGE 2...

High pressure that was in control for the start of the week will slide out to sea early Tuesday as the next system approaches. Temperatures will start out below freezing, so the onset precipitation will be mainly snow. Temperatures will begin to warm up through the morning hours as a warm front lifts north and portions of the region get into the warm sector. As this occurs, there will be potential for sleet and freezing rain. Then throughout the afternoon, wintry precipitation becomes just rain, though a wintry mix will still be possible until the evening hours. Overnight, temperature profiles favor just rain and snow.

There does continue to be uncertainty with precipitation types with this system. High pressure to the north will limit the northern extent of this system, which then factors into what precipitation is observed. Model soundings do show some warming around 850mb but the extent of the warming varies and the thickness of a warm nose will be the difference between freezing rain and sleet. Up until this forecast, we had a simple mix of rain and snow but this update introduced more wintry precipitation types. This was done based on NAM modeled 850mb temperatures given that the NAM tends to handle these mixed events best. Any ice accumulations will be light and are expected early on. Snowfall accumulations will also be on the light side with just a light dusting. N. Oneida could see an inch or more as colder conditions will favor mostly just snow. As precipitation becomes just rain, accumulated ice and snow should melt. Being a couple of days out, the forecast is likely to change with the placement of precipitation types.

KEY MESSAGE 3...

Following Tuesday's system, conditions will trend warmer throughout the week. There is potential for temperatures near or above 60 by the weekend. The pattern will remain active though as multiple systems pass through the region. With milder conditions in place, precipitation will be all rain. The combination of warmer conditions and rain showers will likely wipe out snowpack by the end of the week. There will also be an increased potential for ice jams, especially as ice gets flushed downstream of current build ups. All of this will need to be monitored throughout the week for potential hydro issues.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

Lake induced cloudiness will continue to affect mainly KITH this afternoon with a potential for IFR visibilities in snow showers. KELM-KBGM and KSYR will be on the fringe of this cloud plume and may dip into BKN MVFR ceilings at times. A slow erosion of the cloud field will occur during the evening and overnight period although there still may be low VFR and MVFR ceilings passing through KSYR- KRME prior to 06Z. Strong high pressure then builds in during the overnight hours through Monday with all restrictions lifting to unlimited VFR.

Gusty NW winds this afternoon will diminish tonight and pick up slightly again to 10 KTS or less on Monday.

Outlook:

Monday Night...VFR early with flight restrictions lowering late. Chance for IFR visibilities in snow by morning.

Tuesday...Snow mixing with sleet and freezing rain likely. A good chance for IFR and Alternate Minimums. Mixed precipitation turns to mainly rain Tuesday afternoon and evening.

Wednesday through Friday...Rainy periods likely with a chance for low ceilings, fog, and associated flight restrictions.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...None.