textproduct: Binghamton

WHAT HAS CHANGED

The frontal system that moves through today will exit quickly early Friday morning. QPF amounts were increased for this system, especially as it first moves into the region. PoPs were also added for the off-and-on lake effect snow showers Friday through Saturday night.

KEY MESSAGES

1) Scattered rain showers are expected today and tonight as a low pressure system drags a cold front through the region. A much colder air mass then moves in behind the front.

2) Occasional lake effect snow showers will be possible to start the weekend. Otherwise, high pressure will keep conditions dry through the weekend.

3) There will be multiple chances for showers during the first half of next week as high pressure slides out to sea.

DISCUSSION

KEY MESSAGE 1...

A weak wave will bring some showers through Central NY early this morning though conditions are quite dry. For what can be seen on radar is just virga but there may be some sprinkles or light rain showers before it exits around dawn. Most of the morning hours will then be dry. Temperatures will climb into the 60s and possibly low 70s for those in valley locations.

The main story today is the low pressure system that will move through the region this afternoon. This will initially bring showers to Central NY this afternoon but then spread south into Northeast PA this evening. Extending behind this low is a cold front that will sweep north to south through the overnight hours. Showers will gradually end late tonight into early Friday morning as northerly flow advects much colder air into the region. As it does, there may be a brief transition to snow or rain/snow mix. Behind this front, lake effect and upslope will support light snow showers over portions of Central NY through the late morning hours. A light dusting of snow will be possible for some higher elevations as well as in the Finger Lakes Region.

SPC has General Thunder for the entire region except the northern half of Oneida County. They did extend the Marginal Risk across Central PA and that just clips Steuben (NY) and Bradford (PA) Counties. The majority of model guidance are showing very little of any instability, 100 to maybe 200 J/kg of MLCAPE over Northeast PA. There is slightly better elevated instability. The 0-6km bulk shear will be quite high, over 50 kts. The timing of the system does not favor taking advantage of the instability as precipitation moves into this area late. Given this, there is low confidence that there will be thunderstorms, but it will be something that will still need to be monitored. If skies can clear more than forecasted and the system moves in slightly quicker than expected, then thunderstorms would become more probable. In addition, WPC has most of the region in a Marginal Risk for Excessive Rainfall. Antecedent conditions remain wet from recent precipitation events so flash flood guidance is low. With this system, PWATs are as high as 1.25", which is about 3 standard deviations above normal. Localized heavy rainfall could result in minor hydro issues, mainly in poor drainage areas and where ponding is common. Rivers and streams are low enough that stream flooding is not expected.

KEY MESSAGE 2...

High pressure will return late this week and over the weekend. Cold, northerly flow will support occasional light lake effect snow showers over Central NY Friday and Saturday. Any additional accumulations from these will be light, less than a half inch. Temperatures trend colder through Saturday as temperatures will differ 20 to 30 degrees between today and Friday. Gusty winds will also make it feel blustery at times, especially early Saturday morning when wind chills will drop near single digits. The return of southwesterly flow Sunday will help bring in warmer air as the cold air mass retreats northward. More seasonal temperatures are then expected through the first half of next week.

KEY MESSAGE 3...

The high pressure will slide out to sea late in the weekend. That will open the door for multiple systems to follow the zonal flow into the region. Plus, with the high over the Atlantic, that will be favorable for moisture to be advected from the Gulf into any system moving across eastern CONUS. Despite warmer conditions Monday through Wednesday, there is a chance for showers each day.

AVIATION /12Z THURSDAY THROUGH MONDAY/

VFR conditions expected until the late afternoon, where a frontal system will bring rain into the region with associated restrictions. Ceilings and visibility will drop to MVFR/Fuel Alt with the rain, with increasing confidence that IFR conditions may occur towards the end of the period tomorrow evening.

Outlook:

Thursday night...A rainy cold front will drop northwest to southeast through the region with likely MVFR to IFR restrictions. Snow may mix in before precipitation ends late Thursday night.

Friday morning...Lingering ceiling restriction possible early, but improving conditions expected by midday.

Friday afternoon through Sunday...Mainly VFR conditions.

Monday...A low chance of rain showers and associated restrictions.

BGM WATCHES/WARNINGS/ADVISORIES

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