textproduct: Binghamton

WHAT HAS CHANGED

A severe thunderstorm watch has been issued for all of Central NY and Northeast PA this afternoon and early evening. Otherwise, minor adjustments were made to PoPs through tonight, added in severe thunderstorm wording into the forecast through early evening. Increased winds and wind gusts slightly on Sunday with the cooler, drier northwest flow in place. Lowered overnight lows into the upper 40s to mid-50s Sunday night, along with adding in valley fog into early Monday morning.

KEY MESSAGES

1) Smoke across the region today gets swept out of the area tonight.

2) There is an Enhanced Risk (level 3 of 5) for severe thunderstorms with damaging winds, hail and isolated tornadoes this afternoon and early evening across the entire forecast area.

3) Pleasant, dry and mostly sunny weather looks to return for Sunday and Monday across the area. Cool and refreshing overnight lows.

4) Shower and thunderstorm chances increase Tuesday and Wednesday as the next frontal system pushes east into Central NY and Northeast PA.

DISCUSSION

KEY MESSAGE 1...

Latest runs of the HRRR model smoke guidance show high concentrations of near-surface smoke currently in place. Smoke appears as though it will linger well into the afternoon hours before a cold front sweeps through the region this evening into tonight. Disruption of the airmass due to showers and frontal passages should keep the smoke a little thinner than previous days. Air Quality Alerts remain in effect for Central NY through this evening.

KEY MESSAGE 2...

The initial warm front has pushed through the area this morning and early afternoon with the first round of showers and elevated thunderstorms. Partial clearing will now take place into the afternoon hours, along with dew points surging into the lower or mid 70s and temperatures reaching the upper 70s and 80s for highs. This set up will allow surface base CAPE to rise between 1500-3000 J/kg over the region, with the highest values expected over the Central Southern Tier and Wyoming Valley region by mid to late afternoon. Effective layer shear will be pushing 40-55kts over the entire forecast area by late afternoon as well, creating a favorable environment for super cell development and potential bowing segments. A corridor of DCAPE values above 800 J/kg is also expected to develop just ahead of the incoming storms, so this will set the stage for potential damaging winds and microbursts as storms strengthen. 0-1 km bulk shear is also increase, upwards of 30 kts, and SRH values are up to 300 m2/s2 along the warm front. With low LCLs between 500-750m we cannot rule out an isolated tornado or two this afternoon, either out ahead of the line of storms or embedded within any line segments as they develop and move east- southeast. The timing looks to be mainly between 2PM to 8 PM for the area, starting up across the Finger Lakes, then pushing into the I-81 Twin Tiers by late afternoon and Northeast PA/Wyoming Valley mainly 4-8 PM. SPC has maintained the Enhanced, level 3 of 5, risk across our entire forecast area today.

The storms look to drop south and east, out of the area by 8-9 PM as the cold front passes through. After that, the flow turns north- northwest and a few upslope showers/clouds develop over Central NY overnight into Sunday morning.

KEY MESSAGE 3...

Lingering gust NW flow Sunday, between 10-20 mph may keep some stratus or strato-cu broken clouds around Sunday morning. As high pressure builds in from the west, it will become mostly sunny and pleasant Sunday afternoon. Humidity will be much lower, with dew points in the low to mid-50s and high temperatures in the upper 60s to mid 70s expected. Sunday night a 1017mb surface high moves directly overhead. This will bring clear skies, light winds and allow temperatures to drop between 45-55F overnight. Widespread valley fog is likely to form over the region as well, especially near rivers and creeks. The HRRR keeps the smoke away from our area despite the NW flow on Sunday, and the light overall flow Monday. Therefore, Monday is looking sunny and nice with low humidity and highs in the mid 70s to low 80s. Will continue to monitor the latest guidance for any changes in the smoke aloft forecasts.

KEY MESSAGE 4...

The next front and trough approaches the area later in the day on Tuesday, Tuesday night and into Wednesday. This will bring increasing moisture and instability in the southerly flow on Tuesday. Dew points will rise back around 70F and high temperatures are expected to reach into the lower 80s. This will all depend on the timing of the incoming front thought. SPC does have a portion of the forecast area in a 15% day 4 risk, so we will need to monitor the timing of this incoming system closely for potential organized convection. Showers and possible thunderstorms continue Tuesday night and even into Wednesday at the mid and upper level trough slowly pulls east. Conditions then look to dry out with seasonal temperatures for the end of the work week.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

Fairly widespread smoke has moved into CNY and NEPA today. The smoke should continue to be in place into tonight with continued visibility restrictions. Showers and thunderstorms across WNY should move south and east later this afternoon into the evening. For now, centered each location with approximate timing. While not mentioned in the TEMPOS, strong wind gusts will be possible with the thunderstorms as well.

After the showers and thunderstorms move out of the region this evening a low stratus deck should build in overnight. MVFR ceilings are likely in spots from the stratus deck. Ceilings should lift after sunrise with uncertainity present with how long any smoke lingers.

Outlook:

The rest of Sunday and Monday...Mainly VFR.

Tuesday and Wednesday...A chance of showers and thunderstorms along with associated restrictions.

Thursday... Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...Air Quality Alert until midnight EDT tonight for NYZ009- 015>018-022>025-036-037-044>046-055>057-062.