textproduct: Binghamton

WHAT HAS CHANGED

Increased winds and wind gusts today, with northwest winds reaching up to 25 mph in the early afternoon. Lowered overnight lows tonight under the NBM deterministic guidance, as other bias corrected guidance suggests lows in the upper 30s to mid-40s under ideal radiational cooling conditions. Increased temperatures slightly Tuesday afternoon considering the full day of sunshine, increasing heights, thicknesses and a steady south wind around 10 mph.

KEY MESSAGES

1) Breezy and cooler today with partly sunny skies. Very cool tonight with light winds and valley fog under high pressure.

2) A warm up begins Tuesday and continues through mid to late week. It starts off dry or mainly dry for Tuesday and Wednesday, then shower and thunderstorm chances increase on Thursday.

3) Seasonably mild temperatures return for Friday into the weekend. There will be a slight chance to chance for showers each day with a few frontal systems nearby.

DISCUSSION

KEY MESSAGE 1...

The cold front is currently pressing through Central NY and it will be through NE PA before sunrise. Winds turn northwest and become breezy as cold air advection increases. 850mb temperatures fall to around +5C by early afternoon, and the boundary layer will see deep mixing up to 800mb. This will set the stage for some lake effect clouds to develop and perhaps a few light showers this morning off of the lower Great Lakes and the Finger Lakes. As drier air mixes in through the morning and afternoon hours, skies should eventually turn mostly sunny. The NW winds will be 8-15 mph, with gusts of 20- 25 mph expected...a few gusts to around 30 mph will be possible across any exposed higher elevation locations (such as the Pocono plateau of NE PA). High temperatures will be cool, only reaching into the 60s this afternoon.

High pressure approaches from the northwest this evening and settles overhead tonight, rising to 1028 mb overnight. Winds will quickly diminish toward and after sunset, becoming light and variable. Skies will be clear and overnight lows will dip down into the upper 30s to mid-40s under a steep low level inversion (850mb temps rise to +9C overnight). A few of the colder spots could reach the mid-30s, but confidence on any frost formation remains too low at this time.

KEY MESSAGE 2...

After a cool start Tuesday morning, along with valley fog, it will warm up nicely under sunny skies. A southerly return flow commences through the day on Tuesday, although there could still be some marine component to the flow off to the north Atlantic. Expect plenty of sunshine, dry weather and a large diurnal temperature range, as highs reach into the 70s for most locations. The highly anomalous upper level ridge nudges north into Wednesday, as 850mb temperatures reach +14.5C. Can't rule our a stray shower or t'storm Tuesday night or Wednesday as a weak surface boundary washes out over the area. Forcing will be extremely weak with this feature and the main driver of our weather will continue to the rising upper level heights and thicknesses. While the true core of heat remains well off to the south across the lower Ohio Valley and Tennessee Valley region, our temperatures will rise into the upper 70s and low 80s for Wednesday afternoon, which is about 10 degrees above average for Mid September. The warm weather is forecast to continue into Thursday as an upper level shortwave trough and surface front approach. This setup will bring numerous to widespread showers with a chance for thunderstorms to the area. It will be warm and humid with dew points in the upper 60s to low 70s and temperatures around 80 degrees. With all the showers and storms around skies are likely to be partly to mostly cloudy.

KEY MESSAGE 3....

Temperatures gradually cool Friday and especially into next weekend as the core of the upper level ridge retrogrades slightly west. This will open the door to a more northwesterly flow locally, with gradually falling humidity levels as well. Several front and waves may ride along the northeast periphery of the ridge, keeping shower chances in the forecast. Expect high temperatures in upper 60s to mid 70s over the weekend, with overnight lows mainly in the 50s.

AVIATION /06Z MONDAY THROUGH FRIDAY/

Light showers will linger across the Central NY terminals over the next few hours. Brief MVFR restrictions will be possible, but otherwise VFR conditions are expected. Guidance continues to suggest fog at ELM early this morning, however winds will likely remain too strong for fog development. A tempo group was included to account for the possibility of a brief period of fog should winds become light.

Winds will increase overnight behind the front, with sustained speeds around 10 knots and gusts up to 20 knots Gust winds will continue into Monday afternoon before diminishing during the evening. VFR conditions are expected at all terminals Monday.

Outlook...

Monday through Wednesday...Mainly VFR.

Thursday...Potential restrictions and showers/storms with a front moving through.

Friday...Lingering restrictions possible with recent passing of a front.

BGM WATCHES/WARNINGS/ADVISORIES

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