Marine Weather and Tide Forecast for Great Barrington, MA

NEAR TERM /THROUGH THURSDAY/
Beautiful spring today continues across the region today with plenty of sunshine and temperatures warming comfortably into the 60s with low 70s into the mid-Hudson Valley thanks to deeper boundary layer mixing. Lowered dew points and RH values a bit compared to the previous forecast based on trends and the very dry 12 UTC ALY sounding this morning.

Heading into tonight, high pressure remains in control with mainly clear skies mixing with increasing high clouds after Midnight, especially north of I-90. It will turn chilly tonight thanks to mostly clear skies with temperatures dropping into the low to mid 40s with mid-upper 30s in the southern Adirondacks, southern Vermont, and Upper Hudson Valley.

Clouds continue to increase on Thursday as the surface warm front near the US/Canadian border descends southward towards the Adirondacks. Given that the sfc boundary only reaches our southern Adirondacks and Upper Hudson Valley areas, scattered showers will likely be limited to our northern zones and we thus limited chance POPs to these areas. We extended slight chance POPs down through the I-90 corridor to account for an isolated shower or two that may develop further south based on the latest CAMs including the HRRR as the mid-level front shifts further south. Otherwise, as mid-level ridging expands north and eastward allowing the warm sector to spread into the Northeast, temperatures will respond nicely warming into the low to mid 70s.

The one "fly in the ointment" will be potential for some smoke from the wildfire in Ocean County, NJ to advect into our mid- Hudson Valley and Litchfield County, CT tomorrow afternoon/evening.
Smoke looks to get wrapped into the clockwise/westerly flow around the building high and the latest output from the vertically integrated smoke output shows some smoke could reach into the mid-Hudson Valley and Litchfield County, CT tomorrow afternoon/evening. While values are rather low, it will be something to monitor through tomorrow. Our state environmental agency partners will lead any decisions regarding air quality alerts.

SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/
Key Message:

- Isolated showers/thunderstorms possible (20-30%) for areas mainly north of I-90 Thursday.

- Showers develop late Friday afternoon mainly north/west of Albany (30-50%), becoming a widespread steady moderate rainfall Friday night (80-90%).

Discussion:

Fair and cool for tonight, with lows in the mid 30s to lower 40s.

Upper level disturbance tracking across Quebec may allow for isolated showers for areas mainly north of I-90 Thursday. HRRR mean MUCAPES reach 250-500 J/kg across the SW Adirondacks, so can not rule out an isolated thunderstorm as well. Elsewhere, mostly sunny skies are expected with afternoon temps reaching 70-75 across the mid Hudson Valley and upper 50s to mid 60s elsewhere.

Any early evening showers north of I-90 should give way to clear/partly cloudy skies Thursday night, with lows in the 40s to lower 50s.

Strong upper level shortwave digs into Great Lakes region late Friday/Friday night, with additional lead shortwave and surge of warm advection tracking into region Friday night. This should allow for showers to develop late Friday afternoon, mainly for areas north/west of Albany, with widespread showers and/or a period of steady rain regionwide Friday night. A few rumbles of thunder will be possible as some weak elevated instability (Showalter Indices drop to as low as -1 to -2C) develops.

Prior to arrival of showers, temps Friday should be quite warm for lower elevations along and south of I-90, where high temps should reach 75-80, with mainly mid 60s/lower 70s to the north.
Lows Friday night in the upper 40s to lower/mid 50s.

LONG TERM /SATURDAY THROUGH TUESDAY/
Key Message:

- High probability (70-80%) of at least 0.25" of rain regionwide in 24-hour period ending 8 PM Saturday with medium to high probability (50-65%) of at least 0.5" in same time period.

Discussion:

The weekend gets off to a wet start as a frontal system continues to impact the region. By Saturday morning, the parent low looks to be more or less overhead, placing us in the "warm sector" with its attendant warm front displaced to our east and its cold from approaching from the west. Rain will therefore continue throughout the day Saturday as the low progresses north and east, swinging its cold front through the region Saturday afternoon, and cyclonic flow is maintained by the rotation of a shortwave trough aloft. But with the system swiftly exiting late Saturday evening/early Sunday morning, dry conditions will be reinforced regionwide as surface high pressure and shortwave ridging build eastward. When all is said and done, QPF generally looks to range from about 0.7" to 1". The latter half of the weekend and beginning of the new work week will subsequently remain dry as these fair weather features remain in place. Highs Saturday and Sunday will primarily be in the 50s and 60s with lows in the 30s and 40s. And, with an anticipated warm up in the beginning of next week, these will be the coolest days of the extended period.

Chances for rain increase once again beginning mainly Tuesday evening into Tuesday night as the next frontal system approaches. A few showers out ahead of the main rain shield will be possible during the day Tuesday, but the more widespread precipitation is expected overnight with warm air advection ahead of the incoming warm front. How much rain we receive will depend on the ultimate track of the parent low pressure system, which is still a bit uncertain at this time. But as this seems to be a fairly progressive system, NBM probabilities for greater than 0.25" are fairly low (10- 30%). High temperatures Monday will largely be in the 60s and 70s with lows falling to the 40s. Tuesday's highs will be well above normal with upper 60s to upper 70s expected regionwide before lows fall to the 50s.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/
Through 18Z Thursday...VFR conditions will continue the next 24 hours ending 18Z/THU for KGFL/KPSF/KALB/KPOU with a few-sct cirrus into the early evening. Some mid and high clouds will increase ahead of a warm front, as high pressure drifts east of the region overnight into tomorrow morning. Was not as confident for a lower stratus desk for KALB/KPOU/KPSF towards or shortly after 12Z/THU and kept cigs sct-bkn 5 kft AGL with the mid level clouds over the region. The winds will vary from the west/northwest to north at 8-15 KT this afternoon with some gusts around 25 KT at KALB/KPSF, and then will become light to calm shortly after 00Z/THU. The winds increase from the south to southeast 5-10 KT after 12Z/THU.

Outlook...

Thursday Night: No Operational Impact. NO SIG WX.
Friday: Low Operational Impact. Slight Chance of SHRA.
Friday Night: High Operational Impact
Definite SHRA
TSRA.
Saturday: High Operational Impact. Breezy
Likely SHRA
TSRA.
Saturday Night: Low Operational Impact. Breezy. NO SIG WX.
Sunday to Monday: No Operational Impact. NO SIG WX.

FIRE WEATHER
With high pressure in control, dry weather is expected over the next few days. Afternoon RH values will be as low as 25 to 30 percent in valley areas today, and 30-35 percent Thursday, although they should recover to 70 percent or above at night.
With high pressure nearby, winds will be fairly light, generally under 15 mph or less through Thursday, though a few isolated gusts of 20-25 mph could occur each afternoon.

The next chance for a widespread wetting rainfall looks to be on Friday night into Saturday.

ALY WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...None.
MA...None.
VT...None.