textproduct: Binghamton

WHAT HAS CHANGED

Minor adjustments to cloud cover this evening, tonight and Wednesday as cirrus streams over the area. PoPs were adjusted Wednesday afternoon and evening based on the latest data; this gives the potential for a few isolated thunderstorms mainly in Northeast PA.

KEY MESSAGES

1) Warm and partly sunny weather continues through Wednesday. A few isolated showers or thunderstorms could pop up Wednesday afternoon or evening across the NY southern tier and Northeast PA.

2) A cold front moves through Wednesday night. In the wake of the front, cooler temperatures are forecast for the end of the week.

3) An upper level low pushes through the area Friday night into Saturday with limited moisture and even cooler temperatures. Another upper level low drops down from Canada early next week, but moisture is once again limited.

DISCUSSION

KEY MESSAGE 1...

The next couple of days will be pristine early summer days with ample sunshine, warm temperatures, and lower humidity as dry air continues to advect in from the north.

Expect increasing high level cirrus clouds later this evening into tonight. This will limit fog potential, but still can't rule out patchy valley fog during the predawn early morning hours. Wednesday will feature sunshine filtered through high clouds. Late in the day a weak wind shift boundary drops south and could spark off an isolated shower or thunderstorm across the NY southern Tier and/or NE PA. The best chance to see the isolated activity appears to be shifting south with the latest data, into the Wyoming Valley/Poconos of NE PA. This is where around 500 J/kg of ML CAPE is expected, along with modest deep layer shear (35kts) and just enough moisture will be present. Otherwise, expect warm temperatures Wednesday, with highs in the upper 70s to mid-80s. Dew points will be drier across CNY, in the 50s with slightly higher moisture in NE PA, as dew points reach the upper 50s to low 60s.

KEY MESSAGE 2...

The actual cold front looks to push through the area Wednesday night, as winds shift NNW and temperatures aloft cool to around +6C at the 850mb level. A few more clouds and perhaps sprinkles will accompany the cold front as it moves through. Otherwise, skies should clear for plenty of sunshine on Thursday as the cool northerly flow takes hold. Thursday's high temperatures will be 10- 15 degrees cooler than Wednesday, only in the mid-60s to lower 70s. A shortwave drops south across western New England Thursday afternoon and evening and this will bring a slight chance for a shower in and around the Catskills to Mohawk Valley.

Brief upper level height rises and drier mid level air move in for Thursday night, keeping it dry and cool with lows in the 40s.

Friday starts off dry and mostly sunny, but a potent mid/upper level low then drops south from Quebec late in the day or evening. The exact timing is still uncertain, but latest trends are a little faster with the approach of this low. The low swings a front south through the area, with a slight chance for showers late in the day or evening; especially eastern portions of Central NY.

KEY MESSAGE 3...

The cold core upper level low (534dm thicknesses) dives south across New England Friday night, likely remaining just east of the local area. This feature will bring more clouds and a few scattered showers to our area overnight, with cool overnight lows in the 40s once again. The latest trends are for the upper level low to move/slide faster east of the area on Saturday. That would put our region in a dry northerly flow, with scattered clouds and perhaps an isolated pop up shower for Saturday. NW winds will be breezy between 8-15 mph, with gusts of 20-25 mph expected. With 1000-500mb thicknesses hovering around 546dm, and 850mb temperatures near +2c in the afternoon, it will be quite cool around the region. Look for highs to remain in the 60s across all of Central NY, with some low 70s possible for the Wyoming Valley.

Saturday night sees weak surface high pressure, clear skies, diminishing winds and cool lows in the 40s areawide. Cannot rule out some upper 30s in the normally colder valley locations if the winds decouple fast enough.

It likely stays dry and sunny most of Sunday, however timing differences begin to crop up in the deterministic guidance. Therefore, the official forecast will be made with NBM/WPC guidance which factors in the ensemble data. This again suggests dry weather Sunday, followed by the next digging shortwave trough downstream of the anomalous Omega block heading into early next week. This will be another fairly dry system, with northerly flow and pwats only around 0.50 to 0.75 inches as it swings through. With that said, there certainly could be a few showers around at times and additional clouds moving through. Cool weather continues with below average temperatures Monday, and a slight rebound closer to normal by Tuesday. Ensemble guidance shows gradual height rises over our area heading into the middle of next week, as the weak cutoff low retrogrades back into the Tennessee Valley and an upper level anticyclone develops nearby or over southern Canada and drops south. Exactly how this all plays out remains to be seen though.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

VFR conditions are expected through the TAF period as high pressure sits overhead.

Guidance is hinting at some fog development at ELM, but with warm, sunny weather keeping the surface dry and clouds moving in tonight, fog development seems unlikely. We will continue to monitor how conditions progress as ELM can be very tricky with fog formation, but current confidence in it occurring is too low to include in the TAFs.

Outlook: Wednesday afternoon through Friday...Mainly VFR. Might see a passing shower/storm at AVP late Wed afternoon that could briefly drop conditions below VFR.

Friday Night and Saturday...Chance for scattered showers and associated restrictions.

BGM WATCHES/WARNINGS/ADVISORIES

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