000 FXUS61 KBOX 031124 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 724 AM EDT Wed Aug 3 2022 .SYNOPSIS... Heat and humidity will be the main weather story right through this weekend into early next week. The heat and humidity will peak on Thursday and Friday, with near record high temperatures and oppressive heat indices as well. The greatest potential for showers and thunderstorms will be on Friday with even some localized heavy rainfall possible. && .NEAR TERM /THROUGH TONIGHT/... 0630 AM Update Forecast is on track and no changes are needed at this time. Previous Discussion High pressure builds across southern New England today. Rather quiet day expected weather- wise. Seabreezes expected to develop along the coasts, which will lead to slightly cooler conditions across portions of the coastal plain. Farther inland, not expecting temperatures to be be much lower than yesterday. What should be noticeably lower will be the humidity. && .SHORT TERM /THURSDAY/... Humidity starts to return late tonight, and continues to build Thursday. While expecting rain-free conditions through Thursday, thinking another round of stratus will overspread portions of RI and southeast MA. It is possible this stratus could push farther inland, possibly reaching south central Massachusetts and northeast Connecticut. However, confidence in this is lower, especially with a southwest wind. Continued excellent agreement for oppressive heat and humidity Thursday. Still have greatest confidence in reaching Heat Advisory thresholds, so will continue with that headline for now. CIPS analogs do indicate about a 20-40 percent chance of needing an excessive Heat Warning. So, cannot close the door entirely on that possibility. In either case, it will be very uncomfortable for most. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Highlights * Oppressive heat and humidity continues Friday. Heat Advisory in effect. * Scattered showers and thunderstorms Friday afternoon with local heavy rainfall possible * Hot/humid weather continues trough the weekend and into early next week. Additional heat headlines possible Thursday night and Friday Pronounced Bermuda high pressure system continues to pump hot and humid air into the northeast Thursday night into Friday. Dewpoints surge overnight Thursday into Friday across southern New England, rising into the low to mid 70s. Thus, expect Thursday night to consist of very uncomfortable sleeping weather. Current heat advisory extends into Friday as we'll have a second consecutive day of 850 temps near 20 Celsius supporting surface temps in the mid to upper 90s at the surface across southern New England. While temperatures are not expected to be as warm as what is expected Thursday (see short term AFD) the increased humidity will have heat indices well over 100 degrees again on Friday afternoon. Also can't rule out heat indices perhaps eclipsing the 105 mark which would warrant excessive heat warning headlines. Confidence in reaching that mark is low at this time, so we're hanging on to the heat advisory in the mean time. Highest heat indices expected to reside across the CT and Merrimack River valleys. Some relief will be possible Friday afternoon as a weak surface cold front drops into southern New England. While the forcing associated with this front is expected to be weak, it should be enough to initiate scattered convective showers and thunderstorms across the northern and western areas of southern New England. Weak wind fields will suppress the severe thunderstorm threat, but also introduce the possibility for slow moving storms that will have the ability to produce much needed locally heavy rainfall. This Weekend Bermuda High holds strong this weekend and continues to support a deep southwest flow pattern into southern New England. This will continue to result in above normal temperatures and humidity. Additional heat headlines may be needed this weekend. Heat and humidity will also support an unstable atmosphere during the afternoon hours which will bring isolated shower/thunderstorm chances each afternoon through Monday. May see temperatures and humidity moderate early next week with a cold frontal passage possible during the Monday to Tuesday time frame. && .AVIATION /11Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Today: High confidence. VFR with expected sea-breezes for the coastlines about 15-17z. Tonight: Moderate confidence. Continued VFR for most, though re-developing mist/fog and stratus for the evening for at least the Cape and Islands, but also possible towards south central MA and northeast CT. Thursday: High confidence. VFR. KBOS...High confidence in TAF. KBDL...High confidence in TAF. Outlook /Thursday Night through Sunday/... Thursday Night: VFR. Breezy. Friday through Friday Night: Mainly VFR, with areas MVFR possible. Chance SHRA, slight chance TSRA. Saturday: Mainly VFR, with areas MVFR possible. Breezy. Chance SHRA, slight chance TSRA. Saturday Night: VFR. Breezy. Sunday: Mainly VFR, with areas MVFR possible. Breezy. Slight chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. High confidence. Rather tranquil winds and seas through Thursday. Biggest concerns for tonight are potential for fog, with significant reductions in visibility near the south coastal/nearshore waters. Local nearshore seabreezes today, transitioning to south to southwest winds tonight into Thursday. Outlook /Thursday Night through Sunday/... Thursday Night: Winds less than 25 kt. Friday: Winds less than 25 kt. Chance of rain showers, slight chance of thunderstorms. Friday Night: Winds less than 25 kt. Slight chance of rain showers, isolated thunderstorms. Saturday: Winds less than 25 kt. Slight chance of rain showers. Saturday Night: Winds less than 25 kt. Sunday: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. && .CLIMATE... August 4th daily record maximum high temperatures... BOS - 96F  ORH - 95F  PVD - 98F  BDL - 96F  August 4th daily record maximum low temperatures... BOS - 76F  ORH - 72F  PVD - 74F  BDL - 74F  August 5th daily record maximum high temperatures... BOS - 100F  ORH - 96F  PVD - 100F  BDL - 101F  August 5th daily record maximum low temperatures... BOS - 76F  ORH - 73F  PVD - 77F  BDL - 76F  && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Heat Advisory from 11 AM Thursday to 8 PM EDT Friday for CTZ002>004. MA...Heat Advisory from 11 AM Thursday to 8 PM EDT Friday for MAZ002>021-026. RI...Heat Advisory from 11 AM Thursday to 8 PM EDT Friday for RIZ001>007. MARINE...None. && $$ SYNOPSIS...Belk/RM NEAR TERM...Belk/RM SHORT TERM...Belk LONG TERM...RM AVIATION...Belk/RM MARINE...Belk/RM CLIMATE...