textproduct: Binghamton

WHAT HAS CHANGED

Reduced potential for severe weather this evening, but still a Marginal Risk. Timing for storms is now few hours later, mainly from 8 PM to 2 AM, with a few isolated storms as early as 6 PM possible. Nudged up temperatures Thursday, Friday and Saturday as the cold front is not looking as strong, with more upper level ridging and high pressure overhead by Friday. Timing of the next rain shower potential is not expected to be Saturday evening into Sunday.

KEY MESSAGES

1) Showers and scattered thunderstorms will move through the area this evening into tonight. Isolated strong to severe storms could occur with localized heavy rainfall and gusty winds.

2) Dry weather and seasonably warm weather expected Thursday through Saturday as a flat upper level ridge settles over the area.

3) The next chance for showers and a few thunderstorms will arrive Saturday night into Sunday as a frontal boundary pushes into the area. Then back to mainly dry and warm weather early next week.

DISCUSSION

KEY MESSAGE 1...

A warm front is currently slowly lifting north and east across the forecast area this afternoon. By 5 PM the front should make it to the I-90 corridor between Syracuse and Utica. South of this boundary skies will become partly sunny, temperatures will rise into the upper 70s and lower 80s along with dew points near 70F. This will allow mixed layer CAPE to increase upwards of 500-1000J/kg during the early evening hours. A few isolated storms could develop out ahead of the next incoming wave now located over lower Michigan. Otherwise, as this wave moves in a line of showers and thunderstorms will press east arriving in the Finger Lakes and Central Southern Tier by around 8-9 PM. The line of showers and storms reaches Utica-- Ithaca and Elmira by late evening, then Binghamton, Scranton and Monticello after midnight and into the very early predawn hours Thursday. As this line of showers and storms slowly presses south and east across the area a few storms could produce gusty to isolated damaging winds and there is even an isolated tornado risk (mainly in or near Steuben County). Since the storms will be relatively slow moving, some training of heavy rainfall is also possible, but the flash flood risk is marginal. The showers and storms are forecast to exit NE PA and the southern Catskills between 3-6 AM early Thursday morning. Overnight lows will be mild in the mid to upper 60s with some patchy fog possible.

KEY MESSAGE 2...

The showers and frontal boundary will be well south of the area on Thursday as winds shift to west-northwest and become a little breezy during the day (7-15 mph, gusts to 25 mph. Skies should be mostly sunny through the day and highs look to reach the mid-70s to lower 80s. Dew points gradually fall through the day as drier air advects in on the northwest flow. It will be much cooler and more refreshing Thursday nigh as surface high pressure moves into the region. Expect decreasing clouds from NW to SE through the night, some patchy fog late and lows mainly in the 50s.

Friday will see a strong 1018mb surface high directly overhead through the day. This will mean sunny skies, lighter winds and high temperatures in the low to mid-70s. Went slightly above the NBM guidance for highs, closer to the bias corrected guidance considering the increasing heights and temperatures aloft through the day.

Friday night will likely be the coolest night of the week. High pressure slowly slides east and a stronger low level inversion is likely to form as warmer air aloft arrives. Widespread valley fog is likely to develop in these ideal radiational cooling conditions; lows drop into the mid-40s to lower 50s areawide.

Saturday will feature gradually increasing clouds from southwest to northeast as the surface high retreats off the New England coast. Instability looks to remain mainly west of our forecast area through Saturday afternoon and evening as we maintain a southerly/southeast maritime influenced air mass. As winds turn south and 1000-500mb thicknesses rise above 570dm, expect warm temperatures in the mid- 70s to lower 80s and gradually increasing humidity later in the day. Most of the shower activity is forecast to hold off until after sunset, expect there is a slight chance to low end chance for a few late day showers over western areas of the CWA.

KEY MESSAGE 3...

A flat upper level shortwave and weak surface front are forecast to push through the region Saturday night into Sunday. This will bring a round of scattered to numerous showers, with a chance for thunderstorms as well (mainly Sunday afternoon). This system looks weakly force and instability marginal. Temperatures remain warm in the mid-70s to low 80s on Sunday as there should be some intermittent breaks in the clouds. It is not looking like a washout, but instead just occasional showers or thunderstorms. Shear and instability are looking low on the latest guidance, so at this time we are not expecting organize strong or severe convection.

There is more uncertainty in the model guidance and forecast heading into early next week. Current indications are then Monday will be dry and seasonably as upper level heights gradually amplify over the area. Tuesday will be mainly dry and warmer as a southerly flow takes hold and 1000-500mb thicknesses potentially surge past 576dm A front then attempts to approach by the middle of next week, but could also washout as it heads into the mid and upper level ridge along the East Coast. 500mb heights remain above average over the region Monday through Wednesday, generally around 590dm.

AVIATION /00Z THURSDAY THROUGH MONDAY/

With showers and a few thunderstorms moving across the terminals tonight, flight conditions will range from VFR at times (mainly early) to mostly in the IFR to MVFR range. Conditions will vary as showers and isolated thunderstorms have the potential to drop some brief downpours, lowering VSBYs at times. Cloud bases will also lower with the passing showers and overall moist lower levels. Some of guidance is a bit too slow with the showers/storms moving through, so improvements during the second half of the night are starting to look more likely. With any improvements and rain falling earlier in the TAF period, if there is some clearing, the potential for fog will increase, especially for the more favorable spots such as ELM & ITH.

Thursday, mainly VFR flight conditions are expected. There may be some morning reductions to VSBYs if there is any fog that does develop during the pre-dawn hours. CIGs will also start out in the MVFR range during the morning hours, but will also improve during the morning hours. AVP will have the slowest improvements in CIGs as the wave of showers lingers there the longest. Winds will pickup on Thursday, with gusts in the 15-20 knot range out of the west to northwest.

Outlook...

Thursday afternoon...Mainly VFR.

Friday through Saturday...Mainly VFR with high pressure building into the region. Morning fog will be possible.

Sunday...Restriction possible as frontal system approaches the region.

Monday...Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

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