Marine Weather and Tide Forecast for Champlain, NY

NEAR TERM /THROUGH WEDNESDAY NIGHT/
As of 134 PM EDT Tuesday...The main forecast notes for the near term will be reduced air quality from wildfire smoke and increasing temperatures through mid-week.

Light west/southwesterly flow under ridging will allow wildfire smoke from Canada to continue to spread across the region. Smoke may lead haze with slightly reduced visibilities, particularly near the International Border. The smoke may thicken towards the afternoon based on the latest HRRR/RAP vertically integrated smoke forecasts which may lead to a colorful sunset. By the evening, the bulk of smoke should thin out from daytime mixing and stretched flow aloft. Both the states of NY and VT have issued Air Quality Alerts due to fine particulates, which will remain in effect until midnight tonight.

In addition to the smoke, warm air will continue to increase into the region through mid-week. Little relief is expected tonight temperature wise. WAA will keep lows in the mid to upper 60s to near 70 overnight. Dry and clearing skies will be the theme for tonight. By tomorrow, 925mb temperatures will approach 27C Champlain Valley and near 25C elsewhere. High temperatures are expected to be in the mid to upper 90s in the valleys and upper 80s to low 90s in the higher terrain. While there is a trend towards lower dewpoints into the low to mid 60s from increasing drier air, heat index values in the valleys will approach 95-100F. As a result, a Heat Advisory has been issued for tomorrow from noon to 8 PM for dangerous heat conditions. Be sure to take the necessary precautions if planning to be outside tomorrow.

An upper shortwave, associated with an approaching frontal system will work towards the area late Wednesday night. The latest CAMs suggest a slower moving shortwave which should delay any precipitation chances until late Wednesday night. However, can't totally rule out an isolated passing shower or rumble of thunder across the St. Lawrence Valley or Adirondacks Wednesday late evening. Wednesday night will be warmer than tonight with lows in the upper 60s to low 70s, with some mid 70s across the Champlain Valley.

SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/
As of 134 PM EDT Tuesday...The approaching trough looks to be slower moving as a result of a stronger ridge out ahead. Shower and thunderstorms along a prefrontal trough look to be more likley early Thursday morning than Wednesday night.
Precipitation chances increase into the day Thursday.
Precipitation looks to be fairly scattered during the day Thursday, and primarily terrain driven with the main forcing still to the west of the region. This increase in moisture will drive dewpoints into the 70s and with the delay of the main front, will likely drive heat index values back towards heat advisory criteria in the low to mid 90s. However, if any clouds or showers linger, these high heat index values will be conditional. The heat and humidity will help CAPE values to be near 1500 J/kg with 30-40kts of shear ahead of the front. The lack of immediate forcing during Thursday afternoon should limit most of the severe threat, however, given the incident conditions, some strong to severe storms cannot be ruled out.
Furthermore, pooling moisture will help Pwats be around 1.5" contributing to the potential for heavy rain. The best chances for any stronger storms will be near sunset. Beyond sunset, storm chances decrease as the front pushes through Thursday night with weakened potential energy. Finally some heat relief will filter in Thursday night with lows into the 50s and 60s.

LONG TERM /FRIDAY THROUGH TUESDAY/
As of 134 PM EDT Tuesday...After the stretch of heat earlier in the week, a cold front will finally push through the region Thursday night into Friday bringing much more comfortable conditions. High temperatures will climb into the 70s to low 80s Friday afternoon, with dewpoints only in the 50s making it feel quite comfortable after the prior warmth and humidity. Overnight lows Friday night will be cool, dropping into the 50s with some of the colder locations dropping down into the upper 40s. Seasonable weather looks to continue through the day Saturday, with rain chances return for Sunday although there is still some uncertainty with the exact timing this far out. Seasonable conditions look to continue as we head into early next week.

AVIATION /18Z TUESDAY THROUGH SUNDAY/
Through 18Z Wednesday...VFR conditions currently prevail across all terminals this afternoon, with mostly clear skies.
Visibilities have been reduced to 5-6SM at times due to wildfire smoke and haze across the region, especially across more northern terminals but generally visibilities have been VFR.
Some guidance suggests that additional fog may develop tonight, especially in the more favored areas like KMPV, however the confidence is not high enough to include in the TAF forecast at this time. Winds continue to remain light and terrain driven throughout most of the forecast period, becoming more southerly by tomorrow afternoon.

Outlook...

Wednesday Night: VFR. Chance SHRA, Chance TSRA.
Thursday: VFR. Likely SHRA, Chance TSRA.
Thursday Night: Mainly VFR, with areas MVFR possible. Chance SHRA, Slight chance TSRA.
Friday: Mainly VFR, with local MVFR possible. Slight chance SHRA.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: VFR. Slight chance SHRA.
Sunday: VFR. Chance SHRA, Slight chance TSRA.

CLIMATE
The current forecast highs for Tuesday and especially Wednesday will be within a few degrees of daily record highs, which are listed below.

July 15: KBTV: 93/2013

July 16: KBTV: 96/2018 KMPV: 92/1969 KPBG: 95/1969 KMSS: 94/2018 KSLK: 90/1997

BTV WATCHES/WARNINGS/ADVISORIES
VT...Heat Advisory from noon to 8 PM EDT Wednesday for VTZ001-002- 005-009.
NY...Heat Advisory from noon to 8 PM EDT Wednesday for NYZ026>028- 035-087.