textproduct: Binghamton

WHAT HAS CHANGED

The Winter Weather Advisory already in effect for Northeast PA and a few Central NY counties, was earlier expanded to include remainder of Southern Tier counties as well as Schuyler- Tompkins-Cortland-Chenango-Madison counties. Several of those are dropping at 2 PM but others will persist into the evening.

KEY MESSAGES

1) A system continues to bring wintry mix to the region, transitioning to rain for valley locations yet keeping light freezing rain and snow going into this evening for some higher elevations, especially east of Interstate 81.

2) Warm front will move into the region late Wednesday night through Thursday bringing rain showers. There is a small chance for freezing rain on the front end of it east of Interstate 81 before dawn Thursday, but temperatures will otherwise rise through Friday.

3) Spring-like conditions are expected late this week into early next week with above normal temperatures and multiple chances for rain showers. River rises are expected, with an increasing risk of possible flooding, perhaps including isolated ice jams.

DISCUSSION

KEY MESSAGE 1... A system continues to bring waves of showers through the region, with sensitive temperatures within a few degrees of freezing. The northern edge of the precipitation has been mainly light snow, but thermal profiles throughout the central to southern portions of the area have supported a changeover to sleet, freezing rain, and rain. Many valleys are getting above freezing now which will cease the threat, but higher terrain will continue to be prone to additional light ice accumulation, especially east of Interstate 81 even into this evening. Ice accumulations in the Poconos to Catskills, especially Sullivan County, will push into the one to two tenths of an inch range; trace to less than a tenth of an inch elsewhere. Precipitation in whichever form it takes, will end west to east during 10 PM to 2 AM overnight, but areas of fog are anticipated in its wake with all of this moisture as well as milder air running over the top of cold ground.

KEY MESSAGE 2... A warm front approaches the region Wednesday night, with rain inbound. Temperatures will first fall into the mid 20s to upper 30s in the evening, then slowly rise overnight. If showers run out ahead of the front fast enough, there is a chance that it could start as some brief freezing rain for some areas east of Interstate 81 and into the Mohawk Valley. However, model trends are less progressive for getting the shield of showers in on time for that; still something to monitor. The warm front will slowly lift across the area Thursday through early Friday, with waves running along it causing several batches of showers. Highs of 40s to lower 50s are anticipated Thursday, pressing to mid 40s to near 60 Friday as the warm front makes more headway through the region. These batches of rain will be joined by snowmelt as these warmer temperatures occur.

KEY MESSAGE 3... River rises are expected late this week into early next week, courtesy of multiple waves of showers as well as much warmer weather melting off remaining snowpack. We are anticipating highs of mid 50s to mid 60s Saturday, edging back just slightly to mainly 50s Sunday as another bump in the frontal zone occurs with a wave passage. Rivers and streams will need close monitoring including for possible ice jams. River ensemble forecasts show potential of several points entering action stage if not even possible minor flooding at a couple points. Recent thinning of ice has occurred, but a risk of ice jams is still present. Whatever potential there is, will reveal itself Friday through the weekend because river rises will be significant enough to break up and move the ice. If the ice is thick enough, there could be isolated jams and associated erratic water levels at bridges and pinch points. But if not, the silver lining will be the flushing through of most if not all of the ice in the rivers.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

MVFR-IFR restrictions will continue and become more restrictive through the late afternoon, settling into IFR-LIFR and alternates restrictions early this evening through the overnight hours. Mixed precipitation will blossom more across CNY/NEPA this afternoon, but also slowly trend toward a predominant precipitation type of rain except at KRME where a complete changeover is not expected. Drier air pushes in after 03Z tonight with precipitation ending but ceilings and visibilities remaining poor until Wednesday morning where a gradual erosion of the low clouds is expected during the last portion of this forecast. Overall confidence in the specific details of the restrictive categories, and also the transformation from wintry precip to rain, is low...but the general trend of worse flight conditions tonight is medium.

Outlook:

Wednesday...Restrictions improving to VFR.

Wednesday night through Saturday...Multiple chances for rain and fog with fluctuating restrictions throughout the week.

Sunday...Improving to VFR.

BGM WATCHES/WARNINGS/ADVISORIES

PA...Winter Weather Advisory until 7 PM EST this evening for PAZ038- 039-043-044-047. Winter Weather Advisory until 3 AM EST Wednesday for PAZ040- 048-072. NY...Winter Weather Advisory until 7 PM EST this evening for NYZ022- 036-044-045-056. Winter Weather Advisory until 2 PM EST this afternoon for NYZ023>025-055. Winter Weather Advisory until 1 AM EST Wednesday for NYZ037- 046. Winter Weather Advisory until 3 AM EST Wednesday for NYZ057- 062.