Marine Weather and Tide Forecast for Port Henry, NY

KEY MESSAGES
As of 128 PM EST Saturday...

1. March will start off cold, with well below normal temperatures on Sunday and Monday. Light and fluffy snow still on track for Sunday with limited impacts.

2. A return to more seasonable conditions and potential snow chances for early next week.

3. Warming likely with an active weather pattern forecast.

DISCUSSION
As of 128 PM EST Saturday...

KEY MESSAGE 1: As a cold front continues to push through the region this afternoon, much colder, drier air will filter in behind for the weekend. Temperatures will sharply fall tonight from highs in the upper 30s to low 40s down to the single digits and low teens; a 30- 40 degree drop for some locations. Winds will shift to the northwest drawing further cold air with 925mb temperatures falling to the climatological 10-20th percentiles across the wider valleys by tomorrow morning. A weak thermal gradient will linger across the southern portions of the region which will support some light scattered snow showers. There is not a well defined surface feature to provide a good forcing mechanism, however, a modest low level jet of 30-40kts should promote some marginal lift. The best dynamical forcing looks to be focused in southern Vermont across Rutland and Windsor Counties where a dusting to locally an inch of light and fluffy snow is expected with snow ratios up to 20:1. Thermal profiles further north also depict decent dry low to mid levels which will be hard to saturate across central and northern Vermont.
Nonetheless, a few flurries could be possible across central Vermont and the Upper Valley of the Connecticut, but little to no accumulations are anticipated.

Behind these snow showers, a modified Arctic High will nudge east leading to clearing skies Sunday night into Monday. Clear skies, and weakening winds to near calm will help develop anomalously bitter cold. Sunday night looks like a good candidate for strong radiative cooling into the 25th-10th percentile for overnight lows. Locations across the Adirondacks and St. Lawrence Valley should be able to reach well below zero with some of the coldest hollows of the Adirondacks falling towards -15F. Some lingering clouds across Vermont and the Northeast Kingdom may inhibit efficient radiative cooling at the beginning of the overnight, but these areas should also see some clearing close to sunrise, where the climatologically favored areas could also fall towards -10F, especially in the Lamoille Valley and Northeast Kingdom. Apparent Temperatures will near Cold Weather Advisory criteria (-20F) across the Adirondacks, however, air temperatures should hold below -20F with less time to cool with an earlier sunrise. Additionally any increased winds which would normally push us over the -20F threshold, would lead to more mixing limiting radiative cooling. These competing factors should be able hold the area above any cold headlines.

KEY MESSAGE 2: Following the anomalously cold air over the weekend, the beginning of next week will see a recovery back to normal and perhaps above normal heading towards mid week. The Arctic high will be overhead during the day Monday, but ample sunshine and a subtle waa should help temperatures recover back to the teens to low 20s, or about 15 to 20 degrees below normal. Overnight lows will remain cold Monday night as the high drifts east, but slight southerly flow should limit the radiative cooling effects for most locations. Some ridge riding clouds could also reduce any cooling effect across the St. Lawrence and near the International Border. Lows will dip into the single digits to teens, with some lingering near zero values in the Northeast Kingdom as the high shifts east. Strong waa will take place Tuesday as southerly flow returns, with temperatures increasing to the mid 30s areawide.

Southern stream energy will riding along the western edge of the departing high with chances for precipitation chances late Tuesday.
There still remains some uncertainty for the track of a low pressure system on Tuesday which will impact temperature profiles, and cloud cover which will play a role for viewing the "Blood Moon." Best thinking for the Blood Moon viewing is that any cloud cover Tuesday morning would likely be thin which should support decent viewing conditions. Model guidance remains confident in shower activity Tuesday falling as predominately snow, however, how north the system moves remains in question. Timing also remains a little uncertain, but there is better confidence that precipitation potentially could start during the afternoon hours on Tuesday. The GFS remains the most aggressive and has been relatively stable with a widespread few inches across the region. However, the Euro and AI ensembilistic guidance has shifted south. This shift has been consistent, outside of the 12Z guidance yesterday and is consistent with a more detached high which would limit the southerly flow needed to nudge the system north. There is high confidence in ptype as it stands, but amounts still remain in question. Typically with these zonal flow, and transient systems, high snow amounts are rare, and with PWATs around 0.5," widespread high snowfall is not expected. The character of any snow would be on the wet side should any snow fall, with marginal temperatures in the low to mid 30s.

KEY MESSAGE 3: The confluence of upper level systems and a Bermuda High set up at the surface appears likely to persist into next week. The trouble with these types of patterns is that they often involve small, weak features that are moving at a fast clip. This naturally lends itself to low predictability. However, reviewing any ensemble suite will indicate that PWATs estimating the amount of moisture in the atmosphere will rise above 200% in the midst of the steady stream of systems, and they favor above normal precipitation. Any deviations in the plume of moisture or the exact placement of this tightening thermal gradient will determine how much rain we could observe going forward. It looks like the most likely time frame for the next push of moisture will be Thursday evening into Friday, but model scenarios are not in phase with a wide timing differences.
Expected temperatures will climb into the 40s, perhaps cresting over 50 F towards the next weekend.

AVIATION /18Z SATURDAY THROUGH THURSDAY/
Through 18Z Sunday...A series of troughs are shifting east across the region today. The precipitation piece is about to exit Vermont.
Ceilings range between 3000-7000 ft agl. Lagging LLWS will be possible at KRUT, KMPV, and KEFK until this completely exits. The wind shift piece will arrive about 20z-23z, with a steady transition from south or south- southwest to northwest. Sustained winds in broad valleys (like KMSS and KBTV) have been 15 to 20 with gusts 25 to 32 knots, while remaining TAF sites have been 5 to 12 knots sustained with occasional gusts near 20 knots. As the wind shift takes place, winds will trend toward 5 to 10 knots, and likely stay there through the period. Skies will briefly clear, but once flow is northwesterly (about 01z-03z), ceilings will return towards 3000-5000 ft agl.
Light snow move in from the southwest, but the northward extent is uncertain. At this time, only KSLK and KRUT have prevailing snow, with PROB30s at KBTV and KMPV about 06z-14z. This activity will shift east thereafter.

Outlook...

Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: Mainly VFR, with local MVFR possible. Chance SN.
Tuesday Night: Mainly MVFR, with local IFR possible. Likely SN.
Wednesday: Mainly MVFR, with local IFR possible. NO SIG WX.
Wednesday Night: VFR. Slight chance SN.
Thursday: MVFR/IFR conditions possible. Chance RA, Chance SN.

EQUIPMENT
NOAA Weather Radio station WXM-44, transmitting from Mt.
Ascutney, Vermont, on frequency 162.475 MHz is non- operational at this time. NWS technicians have diagnosed the problem, but repairs will likely not be able to occur for quite some time due to circumstances beyond our control. Therefore, the time of return to service is currently unknown. The following NOAA Weather Radio transmitters may be able to provide service during this outage: WWG 50 from Burke Mtn, VT at 162.425 MHz and WNG 546 from Hanover, NH at 162.525 MHz.

The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS and there isn't an estimated return to service at present. Please contact us if you observe winds significantly deviating from the recreational forecast.

BTV WATCHES/WARNINGS/ADVISORIES
VT...None.
NY...None.