Marine Weather and Tide Forecast for Union Springs, NY

NEAR TERM /THROUGH SATURDAY NIGHT/
935 PM Update...
Things are settling down now with loss of afternoon heating; just some scattered showers left near the I-88 corridor.

Axis of scattered showers and thunderstorms got going late afternoon through early evening along a boundary; basically a cold frontal segment which then reversed to a warm front in central to west-central Pennsylvania; now lifting north near the PA-NY border in the west. The 1000-1500 J/Kg of mixed layer Convective Available Potential Energy (CAPE) was adequate for thunderstorms yet generally sub-severe. However, mesoanalysis Downdraft CAPE values were in the many hundreds to near 1000 J/Kg, suggestive of good downdraft mixing potential for any higher cores. One of these did manage to go severe, with a couple downed trees in Hamilton area. There was also a stripe across southern Madison County where 1-2 inches of rain quickly stacked up from training cells; street flooding resulted.

A small chance of a shower or isolated thunderstorm will exist overnight as the frontal boundary lifts back north as a warm front. However, generally benign conditions, with lows in the lower to mid 60s.

Previous discussion...
While there is still a potential for strong to severe thunderstorms on Saturday, the overall potential is decreasing and therefore most of our region is now in a "Marginal Risk" for severe thunderstorms, rather than a "Slight Risk." This is due to relatively poor instability and lapse rates. There will be slightly higher lapse rates across our far eastern areas (Catskills-Mohawk Valley), so this is where the best chance for severe thunderstorms will be. That being said, it is looking more likely that most of the severe thunderstorms will be located well north and east of our area, more across New England. Otherwise, skies will be partly sunny on Saturday with highs in the lower 70s to near 80.

Flow becomes more westerly behind the cold front Saturday night, which will result in some wrap-around/cold air advection showers, mainly across the Finger Lakes Region. Otherwise, it will become much cooler with lows in the mid 40s to lower 50s.

SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/
230 PM Update...

Unsettled conditions will continue on Sunday with scattered showers as upper level low slowly exits to the northeast. Cool northwest flow on the backside of the low will make for a chilly and blustery day for mid May, with highs on Sunday only in the mid 50s to low 60s. As this system moves east of the region Sunday night, northwest flow will continue to advect cool air southward, however, ridging ridging aloft will also be building in, so the showers will be coming to an end.

Lows on Sunday night will be in the low 40s for most of the region and a few of the coldest spots may drop into the upper 30s.

LONG TERM /MONDAY THROUGH FRIDAY/
230 PM Update...

Dry but cool conditions are in store for next week as a ridge of high pressure builds into the region, and cool northwest flow remains overhead. Temperatures will be below normal throughout the long term period. Winds will remain breezy Monday as with a tight pressure gradient as high pressure builds in.
Patchy frost will be possible Monday night/early Tuesday morning as temperatures plummet under mostly clear skies and calming winds. Dry conditions will continue through at least Tuesday as guidance has slowed down the arrival of the next system. Another upper level low will move into the Great Lakes region Wednesday with a surface low developing off the Mid Atlantic Coast. This system will bring widespread rain to the region Wednesday and Wednesday night with rain then continuing Thursday. It is interesting that the GFS is showing T850 below 0C Wednesday night and T850 below -2C Thursday night into Friday. Still a long ways out, but most of the models and ensembles are in agreement for another cold upper low for the end of the long term period, so at least expecting above average precipitation and below average temperatures as we head into Memorial Day weekend.

AVIATION /02Z SATURDAY THROUGH WEDNESDAY/
Mainly VFR conditions are expected this evening, although isolated showers and thunderstorms are possible mainly at AVP over the next hour or so. Brief MVFR conditions are possible as these showers move through.

Conditions are expected to return to VFR tonight and remain that way through most of the rest of the current TAF period. Another round of showers and thunderstorms will be possible tomorrow afternoon, but confidence was not high enough at this time to include thunder in the TAFs.

Outlook...

Saturday afternoon...Scattered showers and thunderstorms may result in brief restrictions.

Sunday...Scattered rain showers possible, especially at the Central NY terminals, which may result in occasional restrictions.

Sunday night through Tuesday...Mainly VFR expected.

Wednesday...Restrictions likely with rain showers.

BGM WATCHES/WARNINGS/ADVISORIES
PA...None.
NY...None.