000 FXUS61 KBOX 051045 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 645 AM EDT Fri Aug 5 2022 .SYNOPSIS... Heat and humidity will be the main weather story right into early next week. This hot stretch continues today, with even higher humidity. The greatest potential for showers and thunderstorms will be today into Saturday, with localized heavy rainfall possible at times. It may be Tuesday, or later, before this heat and oppressive humidity finally breaks in a significant way. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 645 AM Update GOES Fog channels continue to show some areas of patchy fog and low stratus across southern New England. Fog has become less dense over the last hour and wil continue to lift as the morning progresses. Forecast remains on track and no changes have been made with this update. See previous discussion for additional details. Previous Discussion Another round of early morning stratus and fog towards southeast MA. Expecting more overall cloud cover today, which will result in slightly lower max temperatures today. However, also expecting dew points to be higher, which will keep max heat indices in the 90s across most of southern New England. So, the Heat Advisories will continue as posted. The other concern for today will be the risk for showers and thunderstorms. Mid level moisture will not be as dry as yesterday, making it easier to develop and sustain updrafts. An approaching cold front and mid level shortwave will also provide some support. However, wind fields are generally weak relative to the general buoyancy. Thus, not expecting much risk for severe weather. Any thunderstorms today would pose a lightning and downpour risk. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... With the weak wind fields in place, expecting thunderstorms to diminish quickly after sunset. The same cannot be said for the possibility of showers tonight. Showers and thunderstorms redevelop for Saturday. Have little confidence in trying to time out the risk for specific locations given the rather soupy environment. Have greater concern for downpours than severe weather yet again Saturday. Above normal temperatures and near oppressive humidity continues. Will likely need to extend Heat Advisories for some areas Saturday. These areas could change daily, so will take any extensions on a daily basis. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Highlights * Oppressive heat and humidity continues through Monday. Additional heat headlines likely for Sunday, and possibly Monday. * Slow-moving frontal boundary early next week may support a period of unsettled weather * Temperatures moderate closer to normal mid-week. Sunday and Monday Little change in the weather pattern for Sunday and Monday as deep southwest flow continues to pump warm moist air into southern New England. Dewpoints remain in the low 70s while afternoon temperature stop out in the low to mid 90s. This will translate to heat indices in the mid to upper 90s for both Sunday and Monday. Thus, additional heat headlines are likely for some areas on these days. Most areas are expected to stay dry during this time frame, but with the unstable atmosphere, we can't rule out a brief spot shower or thunderstorm during the afternoon. Next Week Quite a bit of uncertainty beyond Monday as global models are struggling to come to a consensus on how to resolve a slow moving cold frontal boundary early next week. GFS supports an earlier arrival Monday night, while the EURO supports a later arrival on Tuesday. Have leaned on NBM on guidance due to the uncertainty. The expectation is that this frontal boundary will support periods of wet/unsettled weather in the Tuesday to Thursday time frame. Additionally as an upper-level trough associated with this boundary digs into the Northeast, we should see temperatures return to something closer to normal. While the models are in quite a disagreement early in the week, there is better agreement later in the weak for coastal low developing off the east coast. Perhaps this will introduce an opportunity for so much needed rainfall! Check back for more details in the coming days. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Today...Moderate confidence. Areas of LIFR to start the day towards SE MA. Local sea breezes expected to kick in for BOS around 15-17z time frame. Generally VFR elsewhere. Greater risk for showers and thunderstorms, especially across the western two-thirds of southern New England, which could lead to brief MVFR conditions. Tonight...Moderate confidence. Mainly VFR. MVFR/IFR CIGS possible for some, mainly along the south coast, Cape, and islands. TSRA come to an end after sundown, but SHRA are possible through much of the night. Saturday...Moderate confidence. Mainly VFR, with local MVFR in scattered SHRA and TSRA. KBOS...Moderate confidence in TAF, mainly due to timing of any SHRA or TSRA impacting the terminal. Timing of seabreeze development may be off by an hour or so. KBDL...High confidence in TAF. Outlook /Saturday Night through Tuesday/... Saturday Night through Sunday Night: Mainly VFR, with local MVFR possible. Breezy. Slight chance SHRA. Monday: Mainly VFR, with areas MVFR possible. Breezy. Chance SHRA. Monday Night: Mainly MVFR, with areas VFR possible. Breezy. Chance SHRA, isolated TSRA. Tuesday: Mainly MVFR, with local VFR possible. Breezy. Chance SHRA, isolated TSRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. High confidence. Areas of fog should dissipate this morning. Winds and seas to remain relatively tranquil through Saturday. Outlook /Saturday Night through Tuesday/... Saturday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers. Sunday Night: Low risk for Small Craft Advisory winds with gusts up to 20 kt. Seas up to 5 ft. Slight chance of rain showers. Monday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers. Monday Night: Winds less than 25 kt. Seas up to 5 ft. Chance of rain showers, isolated thunderstorms. Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers, isolated thunderstorms. && .CLIMATE... 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 until 8 PM EDT this evening for CTZ002>004. MA...Heat Advisory until 8 PM EDT this evening for MAZ002>023-026. Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for MAZ007-015-016. RI...Heat Advisory until 8 PM EDT this evening 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...