textproduct: Binghamton

WHAT HAS CHANGED

No significant changes were made to this forecast package.

KEY MESSAGES

1) High pressure overhead will slowly slide to the east as today progresses. A weak trough may bring some very light, spotty rain showers tonight.

2) The pattern becomes more active starting Sunday, with several chances for showers and occasional thunderstorms throughout mid-week.

DISCUSSION

KEY MESSAGE 1...

Surface high pressure will continue to keep conditions pleasant today with temperatures in the upper 70s to mid 80s and low humidity. Dry conditions are expected through the evening hours.

A weak shortwave will move into the area tonight as the ridge continues to move to the ENE. Model soundings show pretty dry air across much of the area, so even though CAMs are showing scattered showers developing, there may not be enough moisture available to actually get showers going or if they do, have it reach the ground. The Finger Lakes may provide enough low level moisture to generate a few spotty showers, but most of the area should stay dry. Lows tonight will be comfortable, falling into the mid to upper 50s with some low 60s possible in the northern Finger Lakes and western Mohawk Valley.

KEY MESSAGE 2...

The surface high pressure is now progged to be a little farther to the ENE, with less influence over the CWA. Dewpoints are expected to climb into the low 60s by late Sunday morning as winds become southerly and push some more humid air into the region. This higher moisture combined with a weak trough moving through the area will kick off some scattered rain showers across portions of CNY during the afternoon and early evening hours. A few of these showers may produce some rumbles of thunder, with the best chances west of I-81 where we could see better instability. Model soundings are showing very limited instability east of I-81, which should hinder thunder. Severe weather is not expected.

Much more widespread precipitation is expected to start Monday afternoon. By this timeframe, we are forecast to be on the eastern edge of the big ridge dominating the weather pattern for much of the central and western US and the western edge of a trough axis centered over the Mid-Atlantic. This setup leaves us mostly free of the high pressure suppression and allows for weak shortwaves to move through the area. One of these shortwaves is expected to move in Monday afternoon, which combined with weak instability and dewpoints in the low to mid 60s, should kick off some scattered rain showers and isolated weak thunderstorms.

With the help of a jet streak running along the NE edge of the ridge Monday night into Tuesday, a shortwave is expected to rapidly deepen by Tuesday. How far south this trough digs or if it becomes a cutoff low is still in question, as models have a wide range of solutions. Some show the low moving directly over our area while others have it pushing far to the south. In most solutions however, we are forecast to see widespread rain showers with isolated thunder starting Tuesday afternoon into at least Thursday and possibly early Friday. Up to 2 inches of rain is possible during this timeframe, with higher amounts possible where convection develops. The timing and total rainfall amounts will greatly depend on where the surface low develops and tracks. We are currently in a marginal risk for excessive rainfall leading to flash flooding, but with the recent dry spell and this looking more like widespread stratiform type rain with moderate rainfall rates, flooding chances look to be low. If the low passes more overhead or to our north, we could see greater instability and convection, which would produce greater rainfall rates that could lead to higher flash flooding chances. Since we are not sure where the low will track, a Marginal Risk seems prudent at this time.

Temperatures this week should start off in the 80s on Monday. We should see cooler temps through the rest of the week with clouds, rain, and northerly flow moving back in sometime mid- week. Highs in the 70s are expected until the end of the week when warmer air will ride over the continued ridge over the western US will push temps back into the 80s for Fri/Sat.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

VFR conditions are expected to be in place through the rest of the afternoon and evening. A weak shortwave moving west to east across the area tonight may lead to a stray shower. Currently off to our west across western PA there are some pockets of MVFR ceilings with this disturbance, so that's something to monitor into tonight, especially for ELM, ITH, BGM and SYR. Winds tonight will become light and variable.

Elevated wildfire smoke is expected to move back over the area tomorrow resulting in some hazy skies. Isolated to scattered showers and a few thunderstorms are also expected to develop tomorrow, primarily after 18Z which can lead to occasional restrictions. Winds will start to become SWerly near the end of the TAF period.

Outlook:

Sunday afternoon and evening...Mainly VFR, although isolated to scattered showers or thunderstorms may result in brief restrictions.

Monday through Wednesday...Mainly afternoon showers and/or thunderstorms may result in occasional restrictions.

Thursday...Additional isolated to scattered showers and/or thunderstorms and associated restrictions possible.

BGM WATCHES/WARNINGS/ADVISORIES

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