352 FXUS61 KBOX 060622 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 222 AM EDT Sat Jun 6 2026 .WHAT HAS CHANGED... The Level 2 of 5 (Slight Risk) for severe weather for Saturday late-afternoon to evening has been adjusted eastward into eastern Massachusetts for localized straight-line wind damage. Additional storms are expected starting early Sunday afternoon as well, but these storms should be in the sub-severe range. Finally, small craft advisories have been posted for the southern waters for Saturday. && .KEY MESSAGES... - Warm temperatures this weekend, with scattered thunderstorms (some strong to severe) late in the day into the evening Saturday. Another round of afternoon showers and thunderstorms in greater coverage is expected Sunday, mainly into central/eastern MA and RI. - Cooler start to the workweek gives way to a warming trend with summer-like warmth mid to late week. && .DISCUSSION... KEY MESSAGE 1...Warm temperatures this weekend, with scattered thunderstorms (some strong to severe) late in the day into the evening Saturday. Another round of afternoon showers and thunderstorms in greater coverage is expected Sunday, mainly into central/eastern MA and RI. For Saturday...we'll still be awaiting the arrival of an initial cold front which will be working its way into northwestern MA later in the day. Until then, very warm to hot temperatures are expected Saturday under full sunshine, reaching into the mid 80s to low 90s with a touch of humidity, but not oppressive or enough to raise heat indices to the point of needing heat headlines. The approach of the cold front will be moving into an environment characterized by moderate instability (CAPEs on the order of 1000-1500 J/kg north and west of I-95) and a well-mixed atmosphere favoring strong downdrafts with progged downdraft CAPE values around 700-900 J/kg. There is also some steeper mid-level lapse rates around 6.5-7 C/km, which linger well into the evening hours. Often with mid-level lapse rates at that level, it can sustain thunderstorms even into the evening hours. Wind fields aloft increase some but are not necessarily eye- popping, with 0-6 km shear values around 30-40 kt. The cold front's late timing and that moisture levels are sub-par are main limiting factors to a more organized severe weather threat. We'll probably be waiting for storms to develop and/or move east into western New England until 5-8 PM, and then slowly evolve into a broken line of storms moving ESE through interior Southern New England to the I-95 corridor between 8 pm to midnight, then moving offshore shortly after midnight for the coasts. A Slight Risk (Level 2 of 5) for severe weather has been expanded eastward from central MA/CT and on into the eastern MA metro areas, and the main severe weather risk is for straight-line wind damage and gusty outflow/"microburst" winds which could down trees and powerlines. Thinking the window for storms to become severe is in the 6-9 PM timeframe, then as conditions stabilize, we should see a continued risk for thunderstorms as they move offshore but could still be capable of heavy downpours, lightning and sub- severe wind gusts. Of the two weekend days, it's late Saturday and into early Saturday night that harbors the greatest potential for storms to produce severe weather. The front moves offshore overnight, and with it brings at least a brief period of drier conditions which continues into Sunday morning. For Sunday...we'll start off with drier conditions during the morning hours as temperatures start to warm into the lower to mid 80s with some humidity. We then await a stronger mid-upper level disturbance aloft with a cool pocket of air aloft, which will be digging southward during the early afternoon hours into NH. There should be enough instability around to go along with increasing mid/upper level support from the disturbance aloft and weak inhibition to generate showers and thunderstorms in scattered to even numerous coverage by early afternoon (as soon as noon), then building southeast toward the southern coast thru late afternoon. Instability values look less compared to Saturday, which should temper the severe threat, but storms could still be capable of small hail with the cooler air aloft and localized gusty winds. With not much to force storms other than the disturbance aloft, we couldn't say no to a storm occurring virtually anywhere, but the greatest risk looks to be centered from a Fitchburg- Worcester-Willimantic line eastward to the eastern/southern coast, and a lesser risk westward into the CT Valley/Berkshires. In sum, Sunday could offer a greater thunderstorm coverage than Saturday, but the chances any individual storm reaches severe limits is lower. KEY MESSAGE 2...Cooler start to the workweek gives way to a warming trend with summer-like warmth for the mid to late week. The workweek starts on a cooler note as northerly flow behind a departing trough keeps cooler temperatures aloft. At the surface, onshore flow keeps temps in the 70s at the coast. Further inland, temps warm into the low 80s away from the marine influence. The column quickly warms Tuesday and stays that way through middle of next week as an expansive upper-level ridge builds over the central CONUS. Aloft, 850 mb temperatures soar to +15-18C. Unsurprisingly, dry conditions are likely through much of next week as surface high pressure builds overhead. Bigger story will be the increasing heat starting Tuesday through much of the upcoming week. Ensemble guidance shows somewhat impressively high probabilities for high temps >90F with values between 50 and 60% in the CT and Merrimack River Valleys Tues-Fri. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 06Z TAF Update: Today...High confidence. VFR, though the risk for isolated to scattered TSRA increases after 20Z from KORH westward. A few storms may become strong, with gusty winds and localized turbulence the primary aviation hazards. Greater storm coverage becomes more likely after 00Z farther east. Winds become SW and increase to around 10-12 kt with gusts of 20-25 kt. Tonight...Moderate confidence. VFR outside of scattered thunderstorms, which may briefly reduce flight categories to IFR in heavy rainfall and lower visibility. Initially scattered convection may consolidate into a broken line of storms moving eastward into the ORH/BED/BOS/PVD corridor between 00- 03Z before shifting offshore. A few storms could remain strong early with localized gusty winds, though general weakening trends are favored overnight. Brief clearing develops between 04-08Z from north to south as the front moves offshore. SW winds around 10 kt shift to W/WNW at 5-10 kt. Sunday...Moderate confidence. VFR, though SHRA/TS develops as early as 16Z Sunday across the MA/VT/NH border region and progresses south/southeast through the afternoon. Best chances appear from ORH eastward to the Cape and Islands, with lower coverage farther west. Coverage should diminishes roughly after 21Z. Winds become NW around 10-13 kt before turning NE late in the day. KBOS...High confidence in TAF, though moderate confidence in wind timing. VFR through 00Z Sunday. ENE winds become SW around 16-17Z. TSRA possible after 23Z. KBDL...High confidence in TAF. VFR, with SW winds gusting to 20-25 kt after 17Z. TSRA possible after 22Z. Outlook /Sunday through Wednesday/... Sunday: VFR. Breezy. Chance SHRA, slight chance TSRA. Sunday Night: VFR. Breezy. Slight chance SHRA. Monday: VFR. Breezy. Monday Night: VFR. Tuesday: VFR. Breezy. Tuesday Night: VFR. Wednesday: VFR. Breezy. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Saturday and Sunday...High confidence. Small Craft Advisories have been expanded for Saturday afternoon through Saturday night across the southern waters, eastern waters, and Cape Cod Bay for a combination of SW wind gusts up to 25 kt and building seas of 4-6 ft. There is also a risk for thunderstorms capable of frequent lightning, heavy downpours, and localized strong wind gusts, mainly after 7 PM across both the southern and eastern waters. Another round of scattered showers and thunderstorms develops Sunday afternoon. There could be a period Sunday late afternoon into the evening where portions of the eastern waters experience northerly to northeast wind gusts approaching 25 kt, which may prompt an extension of Small Craft Advisories into Sunday night. For now, advisories remain in effect through Sunday afternoon. Outlook /Sunday through Wednesday/... Sunday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain showers, isolated thunderstorms, patchy fog. Local visibility 1 to 3 nm. Sunday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Chance of rain showers. Monday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Monday Night: Winds less than 25 kt. Seas locally approaching 5 ft. Tuesday through Wednesday: Winds less than 25 kt. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for MAZ013-016>024. RI...Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for RIZ001>008. MARINE...Small Craft Advisory from 2 PM this afternoon to 11 PM EDT this evening for ANZ231-250. Small Craft Advisory from 2 PM this afternoon to 8 AM EDT Sunday for ANZ232>235-237. Small Craft Advisory from 2 PM this afternoon to 2 AM EDT Monday for ANZ254>256. && $$ DISCUSSION...Loconto/FT AVIATION...Loconto/Dooley/FT MARINE...Loconto/Dooley/FT