213 FXUS61 KBOX 212252 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 652 PM EDT Sat Aug 21 2021 .SYNOPSIS... Hurricane Henri approaches southern New England Sunday, slowly crossing the region Sunday night and Monday. Although the track continues to shift a little, the storm has the potential to bring damaging winds, flooding rain, and storm surge flooding. Warm and humid weather should persist next week with scattered showers or thunderstorms at times. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... Satellite images continue to show a mixture of clouds and clear spots. Increased clouds and a few showers to our south. Those clouds will increase tonight. Timing of showers per the ensemble of models points to after midnight, and most places after 3 AM. East to northeast winds will increase after midnight with speeds by sunrise at 10 to 20 mph inland and 20 to 30 mph along the islands. Another very humid night with dew points 68 to 73. Expect most places will have low temps of 70 to 75. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... Overview... Hurricane Henri approaches from the south. Landfall is projected over Eastern Long Island and then the Eastern CT coast Sunday afternoon. The storm then is projected to weaken and slow down, moving to near Springfield MA in the pre-dawn hours of Monday. It then moves to southwest NH by Monday afternoon. Details... Rain reaches the south coast later tonight and spreads across Srn New England by Sunday morning. Based on climatology and the track noted above...we expect strongest winds east of the track. This would be over RI, CT, and the Mass South coast on Sunday as the storm approaches, then spread north into Central Massachusetts Sunday night. Precipitable Water values will be 2 to 2.5 inches during the passage of Henri, which means heavy downpours through this event. Rain will start across all of Srn New England and then re-focus on areas north/west of the storm track. So Western CT/MA are expected to get the most rain. A Flood Watch continues in effect for Wrn/Central MA, Nrn CT, and RI. Hurricane Warnings continue for coastal RI and Block Island. Tropical Storm Warnings continue for Tropical Storm Warnings continue for the Massachusetts South coast including the Islands. Tropical Storm Warnings also for Nrn CT and Nrn RI. As the storm moves into Western MA later Sunday night, expect rain to diminish in Southeast MA and RI while continuing in Nrn CT and Western/Central MA. Temperatures will be slow to change, remaining in the 70s. A few spots on the Cape may reach the low 80s. && .LONG TERM /MONDAY THROUGH SATURDAY/... Highlights... * Lingering showers from Henri through late Monday * Warm and muggy for the remainder of the week * Dry Tuesday through at least Wednesday, afternoon showers possible late week Monday into Tuesday... Henri will linger across NW Massachusetts, eastern NY and Southern Vermont into Tuesday. Widespread rain across the west on Monday becomes more scattered by Tuesday, with the best chance of additional precipitation across our northwest zones. Breaks of sun will develop across the Cape, RI and southeast MA on Monday, with more widespread peeks of sun by Tuesday as the slow moving low finally begins to depart. Dewpoints relinquish slightly behind the departing low, dropping from the mid 70s to the upper 60s and low 70s, but a muggy feeling will stick around for the first few days of the work week. Seasonable temperatures in the upper 70s and low 80s on Monday will warm into the 80s to near 90 by Tuesday as some weak ridging sets up. Tuesday night through Friday night... Dewpoints remain in the low 70s through week's end, combined with temperatures in the upper 80s and low 90s, giving a summer like feel to the air to wrap up the last full week of August. Some weak ridging should keep conditions dry through mid-week, but showers and isolated/scattered afternoon thunderstorms return to the forecast for Thursday and Friday. Temperatures look to cool off late in the forecast period, but the humidity will likely be with us through at least the weekend. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Initially VFR, lowering to MVFR/LIFR overnight as clouds and rain from Henri move in. The rain develops into downpours, especially in Western/Central Massachusetts and Nrn CT with LIFR ceilings and reduced vsbys. The center of Henri crosses coastal southeast CT Sunday afternoon, then moves to near BDL and Springfield MA during the early morning Monday. LLWS likely near Henri. KBOS Terminal...High confidence in TAF. KBDL Terminal...High confidence in TAF. Outlook /Monday through Thursday/... Monday: Mainly MVFR, with local VFR possible. Strong winds with gusts up to 45 kt. Chance SHRA, slight chance TSRA. Monday Night: Mainly VFR, with areas MVFR possible. Breezy. Chance SHRA, slight chance TSRA. Tuesday: VFR. Slight chance SHRA, isolated TSRA. Tuesday Night: Mainly VFR, with areas IFR possible. Wednesday: VFR. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight... Increasing east/northeast wind later tonight, then northeast winds Sunday. Sustained winds 30 kt and gusts 40 kt late tonight on the southern waters. Sustained winds 20 kt and gusts 25 kt late tonight eastern waters. Seas 2 to 5 feet in the east, but building to 10 to 16 feet in the southern waters. Visibility lowers to 3 nm late tonight in rain. Sunday... Hurricane Henri moves north, reaching the eastern part of Long Island early afternoon, then proceding northwest through Connecticut. Expect torrential rain with vsbys 1 to 3 nm, and a chance of a thunderstorm. East winds turn from the southeast and south. Sustained winds 20 to 25 kt on the eastern waters, but building to 45-50 kt on the waters off Rhode Island. Seas 4 to 8 feet on the eastern waters and 10 to 20 feet on the southern waters. Sunday night... Henri moves off through interior New England. Southeast to southwest winds gusting 30 to 40 kt, diminishing late. Seas 5 to 9 feet early, diminishing overnight. Rain showers early, diminishing during the night. /Outlook /Monday through Thursday/... Monday: Winds less than 25 kt. Areas of rough seas. Slight chance of rain showers, isolated thunderstorms. Monday Night through Tuesday: Winds less than 25 kt. Seas up to 5 ft. Slight chance of rain showers, isolated thunderstorms. Tuesday Night through Wednesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Local visibility 1 to 3 nm. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...Flood Watch through Monday morning for CTZ002>004. Tropical Storm Warning for CTZ002>004. MA...Flood Watch through Monday morning for MAZ002>004-008>012. Tropical Storm Warning for MAZ020>024. Storm Surge Watch for MAZ022. RI...Storm Surge Warning for RIZ006>008. Hurricane Warning for RIZ006>008. Flood Watch through Monday morning for RIZ001>008. Tropical Storm Warning for RIZ001>005. MARINE...Hurricane Warning for ANZ235>237-256. Tropical Storm Warning for ANZ232>234-255. && $$ SYNOPSIS...WTB/BW NEAR TERM...WTB/BW SHORT TERM...WTB LONG TERM...BW/KS AVIATION...WTB/BW MARINE...WTB/BW