Marine Weather and Tide Forecast for Barre, VT

KEY MESSAGES
As of 138 AM EDT Thursday...

1. Bermuda high pattern will set up today through next Tuesday, which will bring warm, humid conditions and chances for showers and thunderstorms. A few will be capable of locally heavy rain.

2. Following a seasonably warm and humid period, drier air will arrive by the middle of next week.

DISCUSSION
As of 138 AM EDT Thursday...

KEY MESSAGE 1: Analysis shows strong Bermuda high slowly backing to the east as an upper trough is carving itself out. This upper trough will deepen into an upper low, and this will set the stage for muggy conditions with hit-or-miss shower and thunderstorm activity. Warm, moist advection is already producing some showers around Lake Ontario as moisture rounds a 500mb ridge axis along coastal New England. Increasingly humid conditions will push dewpoints towards 70 as the day wears on. An incoming trough will provide a focus for showers and storms mid-morning through this evening. With no capping in place, activity will likely get underway across northern New York, maybe even by the time this is published, but most likely mid to late this morning. Temperatures will climb into the 80s by afternoon, and this will generate plenty of surface-based instability, especially across northern New York. The benefit to having no capping is that early convection will produce plenty of clouds that will extend northeast in 50-60 knot flow in the upper levels, which will limit solar heating and could prevent heat indices from creeping into the mid 90s. Still with heat indices in the mid 80s to lower 90s, it will feel a bit uncomfortable, today.
So seek shade and drink plenty of water if doing prolonged activities.

This warmth and humidity will help bring PWATs to near 2". Combined with 1000-1500 J/kg of CAPE and trough providing some focus, some heavy downpours will be likely. A few thunderstorms may be strong. 0- 6km bulk shear values are at the bottom threshold for marginal organization (~25 kts), and the newer RRFS suggests some clustering is possible. Sounding profiles match schematics for wet microbursts, and so any stronger thunderstorm may produce gusty winds. However, this will be conditional upon whether mid-morning to early afternoon convection may limit instability through increased cloud cover.

Precipitation chances will dwindle tonight, but not completely hit zero with very moist conditions in place. Dewpoints remain high behind the trough, and so nighttime lows in the mid 60s to lower 70s is expected. Friday's conditions will be similar with 80s across the region. For tomorrow, there won't be quite as much precipitation due to a lack of a trough, and so we may have a better shot at approaching mid 90s heat indices, but will give things time to see how dewpoints trend over the course of today. By Friday evening through Saturday night, a messy conglomerate of troughs will angle northeast. Even with the loss of daytime heating, some showers and a few rumbles could still take place during the overnight hours. Each day should get a little bit cooler at the very least.

KEY MESSAGE 2: The start of next week will feature seasonably warm conditions, although less humid compared to previous days as the Bermuda high weakens and westerly flows prevails across the region. Highs at the start of the week will be in the upper 70s to mid 80s, but by the middle of the week they will drop a few degrees to be in the lower 70s and low 80s. A cold front looks to move through the region sometime late Monday into Tuesday, bringing widespread showers and a few possible thunderstorms, although the timing of the boundary will have a large influence on any convective elements. Towards the middle of next week, guidance suggests that drier conditions return, although we'll have to see as we get closer.

AVIATION /18Z THURSDAY THROUGH TUESDAY/
Through 18Z Friday...VFR conditions currently prevail at all terminals. Showers and a few thunderstorms are expected to move through the area this afternoon and early evening, most likely between 18Z to 00Z, with the potential for reduced flight conditions within any of these showers. The better chances for reduced flight conditions will be across northern New York, especially KSLK, where greater chances for shower activity is expected. Given the uncertainty in the areal extent and timing of any showers, PROB30 groups were used to highlight the most likely time frames. Light southerly flow is expected across the region, with some locally higher gusts possible within any thunderstorm activity. Some guidance supports fog development overnight, especially at any terminals that receive showers, but there is still a lot of uncertainty so have mostly just hinted at that potential.

Outlook...

Friday Night: VFR. Chance SHRA, Slight chance TSRA.
Saturday: VFR. Chance SHRA, Slight chance TSRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance SHRA, Slight chance TSRA.
Sunday: Mainly VFR, with local MVFR possible. Slight chance SHRA.
Sunday Night: VFR. Slight chance SHRA, Slight chance TSRA.
Monday: VFR. Chance SHRA, Chance TSRA.
Monday Night: VFR. Chance SHRA, Slight chance TSRA.
Tuesday: Mainly VFR, with local IFR possible. Chance SHRA, Slight chance TSRA.

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