textproduct: Binghamton

WHAT HAS CHANGED

Little change to previous forecast. Added some thunder in for the overnight hours with the warm front moving in.

KEY MESSAGES

1) A strengthening low passes north of the region Friday into Saturday with a strong frontal passage Friday night.

2) High pressure and southwest flow will lead to a gradual warm up through next week after a chilly weekend.

DISCUSSION

KEY MESSAGE 1...

A deepening low over the central US will lift into the Great Lakes tonight with a warm front moving into the Northeast. Clouds will begin to increase tonight with a strong low level jet developing. Stable air in the low levels will prevent most of the winds from mixing down but downslope areas of the Finger Lakes into the foot hills south of the NY Thruway may see some gusts of 30 mph tonight. Showers and even a few thunderstorms develop tonight as the warm front lifts in so some thunder was added to the grids after Midnight.

The region will be in the warm sector of the low tomorrow. Trends have brought the path of the low a little farther north so odds of some clearing for the Southern Tier and southward has increased. This has helped increase the potential for a little bit of CAPE to develop (roughly between 200 and 400 J/kg). Given shear is over 50 knots, and the cold front being a strong trigger for storms, the potential for thunderstorms along the front to produce strong winds have increased. SPC has moved a slight risk into most of NEPA and parts of the Southern Tier. Forecast hodographs do have some low level curvature ahead of the front, so if there is enough sun to get better surface based CAPE (>500 J/kg), a brief spin up is possible.

Precipitation transitions to lake effect rain showers once the front goes through tomorrow evening. NEPA will dry out quickly behind the front as the lake effect rain showers will struggle to make it much past the Southern Tier of NY. 850 mb temperatures plummet post front, falling to near -10C by Saturday morning. Forecast soundings really dry out the boundary layer and a subsidence inversion lowers quickly but given the lake temperatures, lake effect showers will continue longer than modeled. It is looking likely that some of the higher elevations of NY for the Southern Tier and northward could see some flurries Saturday morning when the coldest air moves through.

KEY MESSAGE 2...

Next week the northeast looks to remain mostly under a large upper level ridge. With weak warm air advection aloft, 850 mb temperatures warm to between 8C and 14C for much of the week. This is well above average for mid October and with dry air in place, sunny conditions will help day time temperatures warm into the 60s and low 70s. Overnight lows will still be on the cooler side with good conditions for radiational cooling most nights.

AVIATION /18Z THURSDAY THROUGH TUESDAY/

VFR conditions expected through the remainder of today and this evening. The next system approaches late tonight into Friday morning. Conditions will start deteriorating after midnight, and will likely continue getting worse through the early morning hours. Rain showers will be possible and there could also be some embedded thunderstorms early Friday morning. Confidence is low at this time for the potential for low level wind shear. Model guidance is showing some mixing overnight and if that is the case, it will be more low level turbulence than low level wind shear. However, where surface winds stay below 10 knots, LLWS conditions will be likely.

Outlook...

Friday afternoon through Friday night...A line of convective showers or thunderstorms will be possible Friday afternoon. Rain showers and some restrictions will likely continue into the night.

Saturday...Lake effect cloud cover keeps cig restrictions likely for all terminals but AVP. Early morning snow showers possible at ITH and BGM.

Sunday through Tuesday...High pressure returns with mostly VFR conditions expected with possible IFR valley fog at ELM in the early morning hours.

BGM WATCHES/WARNINGS/ADVISORIES

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