textproduct: Binghamton

WHAT HAS CHANGED

Increased chances of precipitation Saturday night into Sunday as confidence continues to increase that the low will move just far enough west to bring some rain bands into the area.

KEY MESSAGES

1) Increasing clouds today ahead of a coastal low that will bring some light rain and breezy conditions Saturday into Sunday.

2) High pressure returns early next week with a gradual warm up through mid week.

DISCUSSION

KEY MESSAGE 1...

The high pressure system that has been in place the last few days will gradually fill and move slowly to the Northwest as the coastal low deepens today off the Mid Atlantic coast. High clouds fill in from east to west, filtering the sun by the afternoon. The high clouds as well as increasing northerly winds will help keep tonight's lows 5 to 10 degrees warmer than the last couple of nights.

The coastal low still has a significant amount of uncertainty with the track despite impacts 24 to 36 hours out. The main reason is this low looks to be a bit of a hybrid between a tropical low and a mid latitude cyclone. Deep convection around the core will help with pressure falls while the cool dry air mass and tropical airmass of the coast will provide baroclinicity for pressure falls and cyclogenesis. The combination of a baroclinic process and latent heat release process is something that models do not handle well until the low has consolidated. Even the Convective allowing models struggle mainly because the low is on the edge of their domains and they tend to over do deep moist convection over warm waters. Tonight's model runs in both deterministic and ensemble guidance that has come in has brought the low farther south and west, with occlusion likely happening off the Mid Atlantic coast. QPF and chances of precipitation have been raised slightly region wide. The Catskills may get a bit of a rainfall bullseye with how far west the low looks to potentially end up with moist NE flow. Even under some of the wetter solutions with 2 to 3 inches of rain over 24 to 36 hours, rainfall intensity is below flash flood concerns and amounts are not of concern for river flooding either.

Without much synoptic support due to a weak jet stream and the low moving into cooler waters reducing the deep convection near the center. This likely causes the low to occlude quickly late Sunday into Monday morning with only a few light lingering rain showers by Sunrise Monday.

KEY MESSAGE 2...

Once the low fills and becomes an open wave Monday, Upper level ridging starts to build in with initially Zonal flow becoming Southwest flow by Mid week. A surface high in place coupled with some subsidence aloft under the ridge means chances of precipitation are near 0 late Monday through Wednesday. Towards late week, a few shortwaves look to try and sneak into the Northeast in the SW flow to increase chances of rain slightly. Temperatures will also be slowly warming, getting back above average by mid week.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

LIFR restrictions at ELM will lift by 14z, with VFR conditions through the evening. Another night of fog is forecast at ELM, with LIFR restrictions returning after 08z, lasting into the morning.

VFR conditions are expected at the rest of our terminals through the TAF period.

Outlook...

Saturday morning...VFR conditions expected.

Saturday afternoon through Sunday...Rain and associated restrictions possible, especially on Sunday.

Monday through Tuesday...Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

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