textproduct: Binghamton

WHAT HAS CHANGED

Adjusted rainfall chances through the morning as the warm front lifting in is a little slower so rain will take its time to get here. Rainfall mid week is looking better so increased forecast rainfall Tuesday night into Wendesday night.

KEY MESSAGES

1) A warm front is moving into the region today, with rain showers and isolated embedded thunderstorms this afternoon and evening. Tuesday and Wednesday have a better chance of stronger thunderstorms and heavy rain fall.

2) A cooler pattern with drier Northwest flow returns late week into next weekend.

DISCUSSION

KEY MESSAGE 1...

A large ridge of high pressure across the South Central US is building today with a warm front that is lifting into the Northeast. This front will likely stall in NY down into the Mid Atlantic setting us up to be in the "ring of fire" around the large ridge. Today will have some shear between 35 and 40 knots, though thick cloud cover and frequent rain showers keeps CAPE values low (<300) and elevated so while a few rumbles of thunder is possible, severe weather is unlikely today. 850 mb flow into the warm front does pose a heavy rain threat today and tonight. Training storms are possible, especially north around I-90, where the warm front stalls. PWAT values over 1.5 inches would support higher rainfall rates.

For Tuesday and Wednesday (potentially into Thursday), the set up is better for stronger, more organized storms. With the front stalled around or north of the Thruway, there will be more sun to allow for better heating leading to more surface based CAPE. Tuesday looks to be the warmer day, with ensemble probabilities now near 70% for >1500 J/kg of CAPE along with around 40 knots of shear. One of the things working against Tuesday is the lack of a trigger for storms during the day but even if storms occur early or after dark, there is potential for large hail and wet microburst.

Wednesday has a stronger shortwave passing through. More moisture aloft will likely mean more clouds so that will limit heating and overall CAPE development. Still somewhere between 800 and 1500 J/kg is looking likely. Shear will be stronger, hovering around 50 knots and with the shortwave passing through, a trigger is present to get storms going even without a whole lot of CAPE. One thing that has changed in many of the models from last night is the thermodynamic profile in the lower atmosphere. Many of the models have a back door cold front/marine layer sneaking in with warm moist flow lifting over the stable layer leading to high elevated CAPE. The stable airmass will lower the wind and microburst threat but keep a hail threat for any isolated storms. The forcing in place leads me to believe that storms will grow upscale quickly once they get going in the afternoon/evening with a greater flash flood threat looking more likely. The warm front will still be stalled and could be a focal point for training storms. PWATs near 2 inches and a strong (~40 to 50 knot) low level jet forming in the evening on Wednesday feeding persistent, training storms could lead to significant flash flooding where they end up training. Potential for 4 to 6 inches in less than 12 hours is possible where the warm front ends up stalling. With low level moisture remaining in place Thursday with more sun, instability develops again with high shear once again though the lack of a trigger may keep storms from developing but could have another day with a hail and wet microburst threat.

KEY MESSAGE 2...

For Friday into the weekend, The large ridge in the central US retrogrades west with the trough in the northeast nudging into the mid Atlantic. This will help the flow become more northerly with cooler and drier air advecting in. Depending on how cool the 850 mb temperatures are, there could be some lake effect rain showers to deal with but for the most part the weekend is looking mostly dry.

AVIATION /12Z MONDAY THROUGH FRIDAY/

A mix of MVFR and VFR restrictions this morning as much of the fog that guidance suggested would occur held off due to lack of rain and cloud cover. Scattered rain showers will start to move in from the NW by mid morning, with MVFR restrictions. IFR restrictions will move in at BGM and ITH with the heavier showers starting in the late morning hours. ITH should return to MVFR by the late afternoon, but BGM should hold onto the restrictions. Scattered showers are expected to remain across the area into the overnight hours. IFR restrictions will be possible but confidence in them occurring is too low to include in this TAF set.

Outlook...

Tuesday through Thursday... Scattered showers and thunderstorms possible with associated restrictions, especially each afternoon/evening.

Friday...VFR conditions expected with a few isolated showers possible.

BGM WATCHES/WARNINGS/ADVISORIES

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