textproduct: Binghamton

WHAT HAS CHANGED

No significant changes made from the previous forecast.

KEY MESSAGES

1) A strong cold front will produce widespread soaking showers and possibly a thunderstorm this morning. Locally heavy rainfall could result in isolated ponding on roads.

2) Behind the front it will be breezy and colder with chances for mixed rain and snow from this evening through Tuesday.

3) High pressure and drier weather is expected mid-to-late week with cool mornings and warm afternoons.

DISCUSSION

KEY MESSAGE 1...

The well-advertised strong cold front is working its way across far western NY and western PA early this morning with showers pushing into the western Finger Lakes and up toward the Tug Hill region. The SPC meso analysis shows PWATs of 1 to nearly 1.4 inches and strong shear just off the surface as 0 to 1km bulk shear is shown to be 45 to 50 knots. Winds aloft will continue to increase early this morning (reaching 50 to 60 knots at 850mb) but with model soundings showing an inversion between 1,000 and 3000 ft above the surface, the strongest winds look to have a hard time mixing down. However, a soaking rainfall is still expected as showers spread from west to east this morning with perhaps an embedded thunderstorm, although instability and lapse rates are both lacking. Rainfall amounts of about 1/3 to 2/3 of an inch are expected with the highest totals stretching from the western Mohawk Valley through the Finger Lakes and the lower end of the range expected to be over NE PA and into the southern Catskills. Given the high PWAT values, some of the rainfall can be locally heavy and with the wet antecedent conditions in place, this could result in some ponding on roadways and poor-drainage areas. Areas from I-81 on west remain in a Marginal Risk for excessive rainfall through 12Z this morning from WPC.

Both the HRRR and NAMnest seem to be doing a decent job with regards to timing, placement and intensity of the rainfall thus far and has the rain clearing the Catskills and NE PA between 17Z-19Z.

KEY MESSAGE 2...

In the wake of the cold frontal passage, temperatures will gradually fall this afternoon as the flow becomes northwesterly and ushers in much colder air. 850mb temperatures fall from about 5C early this morning to near -10C by early Monday morning. This combined with strong low and mid-level lapse rates will be enough to lead to a response off the lakes and the development of scattered snow or rain/snow showers starting late this afternoon and evening and continuing through Monday. Snowfall amounts through Monday morning are expected to be light ranging from a dusting to perhaps near a half inch in some places, mainly in higher terrain of CNY. Lows Sunday night range from the upper 20s to the low 30s. Monday's highs are expected to be in the upper 30s and 40s, but the valley areas of NE PA can reach the upper 40s to near 50 degrees.

A clipper system and supporting upper trough is expected to move in Monday night into Tuesday, drawing down even colder air into the region and bring a more widespread round of mainly snow showers. Tuesday's highs will be mainly in the 30s, while overnight lows Tuesday night drop back into the teens and low 20s giving us quite the winter chill stepping out the door early Wednesday morning.

KEY MESSAGE 3...

As the flow aloft becomes more zonal and even features some slight ridging and high pressure builds in at the surface, drier conditions are expected Wednesday and Thursday with moderating temperatures into late week. High temperatures are expected to go from the 40s and 50s Wednesday to the 60s area-wide by Friday. While Wednesday night still looks chilly, overnight lows return to the 40s Thursday and Friday nights.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

Rain has reached the central portion of the forecast area, and will continue to move eastward as the morning progresses. Rain should exit the area around noon. Mostly MVFR restrictions across the terminals this morning, with BGM having IFR ceilings. AVP may see IFR ceilings as the rain moves through in the next couple of hours and the winds shift to more SWerly, pushing valley moisture up to the terminal. BGM and AVP should be MVFR by late morning and mid afternoon, respectively, as the rain exits the area. All terminals should climb to VFR by the afternoon hours.

Lake effect rain showers are expected to develop later this afternoon, with SYR and RME having the best chance to see precipitation. MVFR restrictions are forecast to move in later tonight when ceilings fall and precip changes to snow.

Outlook:

Monday through Tuesday...Scattered rain and snow showers possible, along with possible restrictions.

Wednesday through Thursday...Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

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