textproduct: Binghamton

WHAT HAS CHANGED

Minor adjustments to PoPs, QPF and thunder chances into this evening. Minor adjustments to clouds and isolated shower chances on Wednesday. Increased wind gusts potential Friday night into Saturday behind the strong cold front.

KEY MESSAGES

1)There remains a marginal risk for isolated strong to severe thunderstorms late this afternoon and evening across portions of north Central New York. The best chance to see storms will be along the Interstate 90 corridor and Oneida County.

2) Wednesday is looking mainly dry and seasonable with a mix of clouds and some breaks of sun. High pressure builds overhead on Thursday with increasing sunshine and mild temperatures.

3) A large storm system pushes into the area starting Thursday night. There will be periods of rain and gusty southwest winds overnight into Friday. A strong cold front moves through Friday evening, bringing much colder temperatures, strong northwest winds and a mix of snow and rain showers into Saturday.

DISCUSSION

KEY MESSAGE 1

The warm front remains draped along the I-90 corridor as of 1:30 PM this afternoon. It should nudge a bit more north and east, clearing the CWA heading into the late afternoon hours. Temperatures south of the warm front have surge into the mid-70s to lower 80s as expected, along with dew points getting into the 60s. This will set the stage for increasing instability, as MLCAPE likely reaches 500-800 J/kg by late afternoon. Bulk, deep layer shear is increasing and should be 40-45 kts over north-central NY heading into the early evening hours. A weak perturbation is observed crossing Lake America and Erie at this time. This feature will reach our forecast area between 4-8 PM, and initiate thunderstorms in the rather favorable environment. This event is missing strong forcing to enhance the convective activity. With that said, there remains a marginal risk for an isolated strong to severe storm to bring some hail or damaging wind gusts. Considering the robust low level shear and helicity present, also cannot completely rule out a brief spin up (tornado).

The thunderstorm activity looks to weaken and fade to just lingering showers after about 9 PM based on the latest CAMs.

The rest of tonight will see increasing clouds from north to south and very warm overnight lows in the upper 50s to low 60s.

KEY MESSAGE 2

A northwest flow pattern arrives over the area on Wednesday, with plenty of moisture trapped in the low levels of the atmosphere. There could be a few sprinkles or light showers around at times. Based on current upstream satellite observations over northern lower Michigan, it would not be surprising to see a stratus or strato-cumulus cloud deck form over Central NY and extend into the northern Tier of NE PA through most of the day on Wednesday. There could be a few breaks of sun at times, especially further south and east across NE PA. High temperatures will depend on just how thick and persistent the cloud cover is. The latest guidance is suggesting highs in the 60s for Central NY, with upper 60s to mid-70s in NE PA.

Surface high pressure builds in from the north for Thursday. After some lingering morning clouds it should turn mostly sunny over the region. It will be seasonably mild with highs in the 60s for most.

KEY MESSAGE 3

The next weather system will quickly move into the area Thursday night into Friday, as surface low tracks just north of the area, near Lakes Erie and America. This will bring a period of steady, warm air advection rainfall along the warm front Thursday night. There could be a few brief dry slots on Friday, but there will also be plenty of showers around in the robust southwesterly flow. The cold front then translates east across the area during the day on Friday with additional periods of rain into the afternoon or evening hours. The winds turn northwesterly behind the front and increase between 15-25 mph...gusts could reach 30-40 mph Friday night into Saturday with the deep mixing and steep low level lapse rates up to nearly 750mb level. Wind advisories may eventually be issued for portions of the area if confidence in higher gusts increases.

As cold air advection strengthens, 850mb temperatures drop to -8C to -10C late Friday night and early Saturday. This could allow for wet snow showers to mix in, or become the predominant precipitation type. It is too early to determine how much moisture will be left on the back side of the system and just how much the lakes will get involved. With that said, we cannot rule out some minor, localized slushy accumulations over the higher elevations. Saturday will be downright blustery and cold for mid October standards, with wind chills in the upper 10s to 20s in the morning hours. High temperatures only reach the upper 30s to mid-40s. Now is the time to prepare for this cold blast, make sure your heating source is ready to go for the season and have proper clothing on hand if you need to be outside Friday night into Saturday. It will be another cold one Saturday night, but winds diminish under 10 mph as high pressure builds. Overnight lows dip down into the mid-20s to lower 30s areawide.

Looking ahead, a large ridge of high pressure looks to keep our weather dry with a gradual warming trend Sunday through the middle of next week. There should be plenty of sunshine most days.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

A line of showers pushing through the northern portion of the CWA should bring brief MVFR conditions to RME over the next hour. More showers are expected to develop later this afternoon, bringing MVFR restrictions to RME and SYR. Some of the precipitation that pushes through SYR could be in the form of thunderstorms as temperatures are quickly climbing as clouds clear across the area. Scattered showers are expected to continue around SYR and RME into the early overnight hours.

A wind shift to NWerly is expected to occur starting around midnight as a frontal boundary pushes to the east through the area. This wind shift will bring MVFR to Fuel Alt ceilings across the area through the morning hours. Guidance is trying to develop fog and IFR restrictions at ELM, but model soundings show strong winds just above the surface that should keep fog at bay and limit ceilings to Fuel Alt.

Speaking of strong winds, LLWS is expected to develop at AVP/BGM/ELM between 00z and 06z as a low level winds increase ahead of the approaching boundary. 35kts of shear out of the WSW up to FL020 is expected across the Southern Tier into NEPA.

Outlook...

Wednesday afternoon through Thursday...High pressure building in should result in mostly VFR conditions with the exception of valley fog at ELM.

Friday...Low pressure system approaches the region with restrictions possible.

Saturday...Cooler air settles into the region with the potential for some early season snow showers.

Sunday...High pressure returns with mostly VFR conditions expected.

BGM WATCHES/WARNINGS/ADVISORIES

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