Marine Weather and Tide Forecast for Geneva, NY

KEY MESSAGES
1) Scattered rain showers and drizzle will move through the region this afternoon into the evening, especially across the Finger Lakes and Twin Tiers regions. High pressure builds in tonight with clearing skies and light winds allowing frost to develop across the area.

2) A cool airmass will remain across the region through the weekend with scattered rain showers expected Friday and Saturday. Snow may mix in across higher elevations starting in the Friday evening/night. Temperatures will fall into the low to mid 30s 30s thru Sunday, allowing for continued frost/freeze chances in our growing zones.

DISCUSSION
KEY MESSAGE 1...

Patchy drizzle remains across portions the area this afternoon.
A line of rain showers and drizzle is moving in from the west, and if the showers can hold together, rain and drizzle should fall across portions of the Finger Lakes, Twin Tiers and Wyoming Valley late this afternoon and evening.

Conditions will dry out by mid to late evening as high pressure builds in from the WSW. NW flow from the incoming high will push a cold airmass into the region from Canada, and combined with clearing skies and light to calm winds, temperatures are expected to fall into the low to mid 30s. The growing season starts in the Finger Lakes region and the Wyoming Valley tonight, and with forecast conditions showing frost potential, a Frost Advisory has been issued for Yates, Seneca, S Cayuga and Onondaga counties in NY and Lackawanna and Luzerne counties in PA. Frost will probably occur outside these counties as well, but the growing season does not start until May 11 for the rest of our CWA The Frost Advisory will be in effect from 11pm this evening to 9am Friday.

KEY MESSAGE 2...

An upper level low spinning between the Great Lakes and Hudson Bay will be the main weather driver for the weekend. The broad trough sitting overhead will keep temperatures about 10 degrees cooler than normal for this time of year. A shortwave will move through the area Friday, developing a weak surface low south of the Great Lakes that will track to the east. This low will bring scattered rain showers to the area Friday afternoon into the overnight hours. 850mb temps in the -3C to -4C range during the evening and overnight hours will allow for snow to mix in across higher elevations where precipitation remains.

Lows Sat and Sun night will be cold once again, with low to mid 30s expected. Sunday night looks to be the coldest, with widespread temps near freezing as we should see radiational cooling under high pressure. Frost advisories or even a freeze warning might be needed, especially if skies can clear out and winds become light enough.

Southerly flow will return Monday, pushing temperatures back into the 60s. Tuesday will be warmer with upper 60s to mid 70s forecast. Unfortunately, rain is expected to return with these warm temperatures as a strong trough and associated cold front will move into the area mid-week.



AVIATION /18Z THURSDAY THROUGH TUESDAY/
Some lingering MVFR/Fuel Alt ceilings will be possible this afternoon. Otherwise, skies will scatter out some with conditions becoming VFR at all terminals later this afternoon. There may be some spotty showers that could impact ELM and AVP this afternoon as well though chances were too low to include in the TAFs. If a shower were to move over one of these terminals, brief reductions in visibility may be possible. Northwest winds will be breezy with speeds of 5 to 10 kts and gusts around 15 kts. Winds then become calmer overnight though will mainly be west to northwesterly.

Outlook:

Friday Afternoon through Monday... Mainly VFR, but restrictions will be possible at times in isolated to scattered showers.

Tuesday...Widespread showers and associated restrictions possible.

BGM WATCHES/WARNINGS/ADVISORIES
PA...Frost Advisory from 11 PM this evening to 9 AM EDT Friday for PAZ044-047.
NY...Frost Advisory from 11 PM this evening to 9 AM EDT Friday for NYZ015>018.