textproduct: Binghamton

WHAT HAS CHANGED

No significant changes were made with this forecast update.

KEY MESSAGES

1) Warm temperatures and increasing humidity are expected across Central New York and Northeast Pennsylvania into Friday.

2) Scattered showers and thunderstorms return to the region Thursday afternoon through Friday before quiet weather and high pressure build back in for the weekend.

3) After seasonal temperatures this weekend, heat builds into the area through the middle of next week.

DISCUSSION

KEY MESSAGE 1... Weak ridging over the area has brought mostly sunny skies and has allowed temperatures to climb into the upper 70s to low 80s. Temps should rise a few degrees more as we enter peak afternoon heating.

WSW flow returns tonight as the ridge slides east and a trough digs into the Great Lakes. This flow will push warmer, more humid air into the region. Temperatures Thursday will climb into the mid 80s to low 90s for most, with dewpoints in the mid 60s. The higher dewpoints will make if feel a little muggy out, but we will not be hot enough to necessitate any heat headlines.

The axis of the aforementioned trough will move through the area Thursday night into Friday morning. This will help push temperatures down into the upper 70s to mid 80s across the region. A ridge will build into the central US this weekend, bringing WNW flow to the area and seasonable temperatures.

KEY MESSAGE 2... Most of the area should stay dry today, although a weak shortwave looks to move into central PA, kicking off some isolated showers across the western Finger Lakes later this afternoon into the evening. A few rumbles of thunder cannot be ruled out but severe storms are not expected.

More widespread rain showers and storms are expected for Thursday into Friday, with 2 different features helping to generate precipitation across portions of our area. First, a shortwave will push into the Mid-Atlantic Thursday morning, kicking off scattered showers and storms across portions of NEPA. Most of the heavier rain looks to stay to the south, but showers and storms may skirt portions of the Wyoming Valley into the southern Catskills starting in the late morning through the afternoon hours. Guidance shows weak CAPE and shear over the area during much of the afternoon, keeping any convection that develops elevated and weak. The cap looks to break later in the afternoon and evening, but the forcing will be east of the area, limiting precipitation. The better chance for strong to isolated severe storms will be across the northern portion of the CWA as a frontal boundary on the leading edge of the trough axis moves into the area late in the afternoon to evening hours. Stronger bulk shear of 25-35kts is modeled to accompany this boundary with modest CAPE around 1000 j/kg. This should kick off some scattered storms, with a few isolated severe storms possible. Damaging winds would be the main threat with these storms. Isolated flash flooding will also be possible as the CAPE over the area looks to be long and skinny, with PWATs in the 1.5-2in range, warm cloud depths around 12k feet and MBE vectors of 5-10kts. These parameters point to slow moving or back building storms with heavy rain leading to isolated flash flooding. This threat looks to be the greatest from the late afternoon into the early overnight hours.

The frontal boundary looks to push through the area Thursday night into Friday morning, but the timing is currently a little unsure with some models have an early overnight passage, while others push it through late overnight/early Friday morning, slowing down in the late morning/early afternoon as it approaches the NY/PA border. If the passage is towards the later solution, a shortwave moving into the area from western PA will kick off scattered showers and storms across the Twin Tiers and into the Poconos during the afternoon and evening hours. The slow moving frontal boundary near the NY/PA border providing enhanced lift of warm, moist air as the shortwave moves across the region could generate multiple storms with heavy downpours impacting the same areas causing isolated flash flooding. Because of this, a Marginal risk for excessive rainfall has been issued for this area.

Precipitation chances move out of the area by late evening, with high pressure building in for the weekend.

Key Message 3... A very strong ridge will build across the central US starting Monday, bringing very hot weather to the area. Some of this heat will propagate along the northern edge of the ridge and slide into our area starting Tuesday. Widespread mid 80s to low 90s will be possible Tuesday and Wednesday. A front and associated trough may dig into the area after Wednesday, bringing some cooler weather, but confidence in this is low at this time as model guidance is too varied on the timing of the front and when/if the ridge weakens.

AVIATION /00Z THURSDAY THROUGH MONDAY/

Mainly VFR throughout the TAF period. Will have to watch for possible fog at KELM overnight. Also, a MVFR stratus deck may work into KAVP for a few hours as well. A few showers and thunderstorms may develop during the afternoon hours. Confidence and expected coverage at this time only warrants mention of a VFR shower in the afternoon hours Thursday.

Outlook:

Thursday night...Mainly VFR.

Friday...Cold front could moves in, with isolated to scattered rain showers and thunderstorms. Restrictions possible.

Saturday into Monday...VFR likely with high pressure building in, morning fog potential at ELM.

BGM WATCHES/WARNINGS/ADVISORIES

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