textproduct: Binghamton

WHAT HAS CHANGED

Very few changes to the near term forecast with this update. Continued to keep dew points a little lower than modeled for mid week, and lowered high temperatures slightly as well given potential cloud cover and pop up afternoon thunderstorms.

KEY MESSAGES

1) Isolated showers or a thunderstorm may occur primarily over Northeast PA and the higher terrain of the Southern Tier and Catskills this afternoon.

2) Heat and humidity will be increasing through this week leading to elevated heat indices.

3) With the heat and humidity, Tuesday through the end of the week could have daily isolated to scattered thunderstorms, some of which could be strong.

DISCUSSION

KEY MESSAGE 1...

Low chances of thunderstorms were kept in for the Catskills and Poconos and vicinity given terrain driven convection. Satellite early this afternoon shows some agitated cumulus developing with day time heating. Water vapor imagery does show a good amount of dry air moving in so this deeper convection is helping to mix down this drier air. It will be a battle between the drying of the boundary layer and deepening convection through the afternoon but the highest terrain of the Catskills has the best chance of convection overcoming dry layer aloft. If a storm does pop up, it will be slow moving with heavy rain so a quick inch under a thunderstorm is possible.

KEY MESSAGE 2...

A strong ridge builds into the Eastern US this next week with temperatures and dew points gradually increasing each day through late week. 500 mb heights rise over 590 dm with 850 mb temperatures greater than 20C so afternoon highs will be well into the 90s for most of the region starting Wednesday through the remainder of the week. Dew points look to climb into the upper 60s and low 70s as well. NBM blends continue to have mid 70s for dew points which is likely a high bias, especially where westerly component winds are a drying downslope off the Allegany Plateau. That said, moisture in the boundary layer can sweep into the lake plain from WNY where higher dewpoint values across much of the Ohio River Valley are well above average so the Finger Lakes and Syracuse area could see oppressive mid-70s dewpoints. One thing that could limit our warmer temperatures and prevent upper 90s and even a few 100s in urban areas for air temperatures will be afternoon convection. Despite the ridge, there will not be a lot of CIN so showers and storms could develop early afternoon and help keep highs slightly cooler. A front dropping out of Canada this weekend may keep temperatures a little cooler, and lower dew points a bit as well.

KEY MESSAGE 3...

Chances of Thunderstorms have been kept for each afternoon from Tuesday onwards as the dew points climb along with the temperatures. MLCAPE rises to 1000 to 2000 J/kg each afternoon. Right now, triggers for storms are tough to pin down as we are near the NE edge of the ridge with shortwaves that will be riding around the perimeter of the ridge. Forecast soundings do keep come CIN but it is not much. Storms may be able to fire without a trigger as well over higher terrain, then outflow from those could continue to support additional storms into the early evening.

Tuesday still looks the most interesting for storms, given an Elevated Mixed Layer is moving through, leading to modeled 700-500 mb lapse rates near 8C/km. Shear is lacking (<30 knots) for a bigger event as well as an obvious trigger, but many models at least fire off some convection. Downburst will be possible with initial convection given the CAPE and Mid Level Lapse rates. Forecast soundings also show warm cloud depths over 10K feet with potential for training given flow aloft so a flash flood risk is there as well high high rainfall rates that could approach two to three inches an hour.

The threat for downburst lessens and becomes more isolated Wednesday onwards as mid level lapse rates trends back towards 6C/km but the CAPE will be high each afternoon. Low level flow and mid level flows align better later in the week for training storms so if we do get storms to fire or if the ridge does not build as far into New England with the ring of fire closer to our CWA, we could be dealing with a persistent flash flood risk.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

VFR conditions are expected area-wide through at least 06Z tomorrow. Patchy fog will once again develop late tonight/early tomorrow morning, which will result in a return of visby restrictions, especially at KELM and possibly at KAVP. Otherwise, other terminals are expected to remain VFR.

Outlook:

Tuesday through Friday...Mostly VFR, but some restrictions will be possible with isolated showers and thunderstorms each afternoon.

CLIMATE

Current High Temperature Records:

6/30: BGM - 92 (1964), SYR - 94 (1971), AVP - 97 (1964) 7/1: BGM - 90 (2018), SYR - 94 (2018), AVP - 95 (2018) 7/2: BGM - 92 (1966), SYR - 96 (1963), AVP - 98 (1966)

BGM WATCHES/WARNINGS/ADVISORIES

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