textproduct: Binghamton

WHAT HAS CHANGED

No significant changes were made to the forecast with this update. Current model guidance remains very consistent for the upcoming week.

KEY MESSAGES

1) Mainly dry and warm weather expected for the rest of today into Monday. However, there will be a few isolated showers or thunderstorms developing across the Wyoming Valley and Poconos this afternoon and early evening.

2) Hot, sunny and dry weather will take hold over the forecast area for Tuesday and Wednesday. Heat indices may reach the mid-90s to around 100 degrees in some locations.

3) An upper level trough moving over the Northeast likely brings temperatures back down closer to average by the end of the week, with a few shower chances by next weekend.

DISCUSSION

KEY MESSAGE 1...

A scattered to broken cumulus cloud field has developed across the Twin Tiers, Catskills and NE PA early this afternoon. Surface dew points are certainly much drier than previous days though, now ranging from the upper 40s to 50s in most locations. Latest mesoanalysis from SPC/RAP data shows no surface based CAPE across Central NY, with between 100-500 J/kg in place over NE PA...with the higher end values over western Luzerne County. With the drier low level air mass in place, MLCAPE is even lower, less than 100 J/kg even in NE PA, with MLCIN still in place. Forecasts from the RAP show that MLCAPE bumps up to perhaps 200 J/kg over portions of the Wyoming Valley and surrounding hills later this afternoon. Therefore, left in isolated shower/t'storm chances here between 2-8 PM this afternoon and evening. The rest of the forecast area is expected to remain partly to mostly sunny, dry and warm through this evening. Highs reach into the 80s areawide.

Tonight features mostly clear conditions, light winds and perhaps just some very patchy river valley fog. Lows will be in the upper 50s to lower 60s.

High pressure is in place on Monday, bringing dry and very warm conditons. Humidity levels will remain low, with dew points in the mid-50s to low 60s expected. Skies remain sunny to mostly sunny and high temperatures will reach well into the 80s...with even low 90s for the Mohawk Valley and Syracuse metro area. Can't rule out an isolated afternoon shower or t'storm near or just south of the Utica and Syracuse areas as a weak boundary pushes through. Model soundings do show just enough moisture, lift and instability (MLCAPE 500-1000 J/kg north of the NY Southern Tier) to potentially initiate some convection. Otherwise, expect generally light southwest winds under 10 mph through the day.

KEY MESSAGE 2...

Upper level heights rise through the day on Tuesday, as the large heat dome shifts east from the Great Lakes region. 500mb heights are progged to reach 594dm early Tuesday afternoon, along with 1000- 500mb thicknesses of 582dm and 850mb temperatures at +23C. With a fairly dry air mass still in place (Tds 60-68F) and full sunshine expected, daytime highs will reach the upper 80s to mid-90s over the area. Lowered these numbers 1-2 degrees from the likely overly aggressive NBM Max T guidance, which had widespread mid to upper 90s in the valleys. The hottest part of this incoming air mass appears to settle in across Central NY, with NE PA still being hot, but not as anomalous. With the above mentioned dew points in the 60s, heat indices will reach 95 to 102F in the valleys of Central NY. If confidence continues to build in this scenario, heat advisories may very well be needed for parts of Central NY. Heat indices in NE PA's valleys look to max out in the mid-90s Tuesday afternoon...below heat advisory criteria. Soundings show a very strong cap in place between about 650-850mb across the entire area Tuesday afternoon and evening; this will prevent any convection from forming even with Surface Based CAPE values between 1500-3000 J/kg expected. The LFC remains near 10k ft or 700mb, with dry air in place at and above this level in the forecast soundings from the 12z NAM. There will also be some breezy west winds at times between 10-20 mph.

Tuesday night will see mainly clear skies for most of the area. Some increasing clouds are possible across the Mohawk Vally and Oneida county as showers and t'storms likely pass by to the northeast with a shortwave disturbance. Lows will be quite warm only dipping into the upper 60s to mid-70s.

The upper level ridge flattens by Wednesday, with heights falling back to 585dm at 500mb as the northwest flow increases. 850mb temperatures are expected to reach +17C in the mid afternoon hours. A drier and cooler air mass does begin to advect into the area from southern Ontario through the day. With a warm start in the 70s, model guidance is still showing temperatures peaking in the mid-80s to low 90s across the area (perhaps still mid-90s Wyoming Valley). Surface dew points start in the mid to upper 60s in the morning, but then fall into the 50s and low 60s by afternoon. Breezy northwest winds are expected between 10-20 mph once again. Max heat indices will only peak in the 80s to low 90s across Central NY, with upper 80s to mid-90s in NE PA. It's possible the Wyoming Valley region in Luzerne county could see a few hours with a heat index in the 95- 100F range...which is still close to heat advisory criteria here. Otherwise, the air mass will remain dry and capped with mostly sunny skies expected areawide.

KEY MESSAGE 3...

Upper level trough deepens over the Northeast US for the end of the upcoming work week. Most guidance keeps it dry over the area, with a northwest flow continuing. With plenty of sunshine and no strong cold air advection high temperatures remain seasonably warm, in the upper 70s to mid 80s right into next weekend. Moisture does gradually increase from the west again by next weekend and there could be some scattered showers around from time to time. Thunderstorm chances remain low, with very limited instability expected.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

Fair weather cumulus clouds have developed over the region. Otherwise, high clouds will be present through this TAF period. A pop up shower or will be possible at AVP late today. Some guidance hints at fog for ELM early Monday morning though conditions should be too dry for fog. Winds are expected to be light and variable until after sunrise when winds settle out of the west-southwest.

Outlook:

Monday through Friday...Mainly VFR; patchy morning low clouds/fog possible.

BGM WATCHES/WARNINGS/ADVISORIES

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