138 FXUS61 KBOX 121233 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 833 AM EDT Sat Apr 12 2025 .SYNOPSIS... Low pressure near Delaware will slowly move northeast today and tonight. Continued coastal rain and interior high terrain wet snow and rain through this morning. Precipitation will taper off to pockets of light rain and drizzle this afternoon and tonight. Additional showers are likely in eastern New England on Sunday. Brief dry period Monday with more seasonable temperatures before more rain arrives Monday night and remains into Tuesday. Cooler yet dry and blustery conditions make a return Wednesday into Thursday before more unsettled weather may arrive heading into the weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 830 AM update... Heavy elevation snow across interior northern MA will begin to taper off during the next few hours as dry slot lifts north across the region and snowgrowth region dries out. Have received reports of up to 6-7" of snow accum across the northern Worcester Hills. Additional snowfall of an inch or 2 is possible in the higher elevations before the snow tapers off to a light rain-snow mix or snizzle. Otherwise, it will be a raw day with areas of drizzle and gusty NE winds. Not much temp recovery with temps remaining in the 30s for most locations, except rising into the lower 40s along the south coast. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... 330 AM Update: Key Messages: * Continued overcast with drizzle and mist and onshore breezes tonight. Little if any temperature change from overnight. * Overcast for most areas Sunday, with another round of steadier light rain for eastern New England for Sunday. We could break free of clouds late in the day with peeks of sun in the interior. Temps in the 40s east, to the upper 40s/near 50s western New England. Details: Tonight through Sunday: Overcast, drizzly and misty conditions then look to continue into tonight, as the system's upper level low crawls from northeast NJ into CT/RI by daybreak. NE winds will also continue at around 10-15 mph, but we should see a gradual decrease in NE speeds compared to the daytime. Low temperatures are not expected to fall very far either with readings in the 30s being common. A bit more uncertainty as we move into the Sunday period, as it pertains to another potential round of steadier light rain moving landward from the southeastern waters. This is in association with a secondary area of low pressure east of the southern mid- Atlantic waters that tries to move north and/or northwestward around the system's mid/upper low expected to be located near southern CT/RI. Model guidance has shown large variation in how far west would any steadier light rains advance, although recent model runs have shown more of a westward trend, with the western periphery of steadier light rain into central MA and eastern CT. The exact placement is still a little uncertain but felt there was enough consensus in the QPF placement to raise PoP into eastern MA toward the high Likely to categorical range starting early Sunday morning. Will also point out that this second round of rain for Sunday is not a substantial QPF event, with totals in eastern MA up to an additional quarter-inch before tapering off/returning seaward late in the day. The further west one goes, especially western MA and most of CT, these areas seem less likely to see any additional rain at all, although it will still be generally overcast. There is some optimism these western areas could break free of the overcast and even eke out some peeks of sun late in the day. If we can break out from clouds in western New England, we could see highs nearing 50 degrees. Coldest high temperature readings the further east one goes, in the low to mid 40s, given overcast and continued onshore breezes. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Key Messages: * Rain exits the region Sunday night, then showers return Monday night with another frontal system * Below normal temperatures midweek with blustery and dry conditions * More wet weather possible towards the weekend Details... Rain over eastern MA ends as the cutoff low to our south moves offshore Sunday night and brief ridging builds in Monday ahead of another frontal system. More seasonable temperatures will make a return, then showers return Monday night and linger through Tuesday ahead of a cold front. 925 mb temperatures aloft are still expected to reach up to +10C; highs for the start of the week in the 60s can be expected. Cooler and drier conditions return going into midweek following the passage of a secondary cold front. In terms of QPF, ensembles indicate 24 hour accumulations ranging from 0.10" to 0.25", the GEFS running slightly higher and the ECMWF ensemble running slightly lower. Despite this front's passage, the upper trough remains over Ontario/Quebec. Lows Tuesday night and Wednesday night will return to the 30s and 40s. Highs Wednesday will range from the upper 40s to low/mid 50s. Winds will pick up slightly to start the second half of the week following the cold front from Tuesday night/Wednesday. Temperatures aloft decrease; 925 mb temperatures go back to around -5C to 0C. Dry and blustery conditions can be expected Wednesday into Thursday. Unsettled weather looks to make a return with another shortwave moving across the Great Lakes and into New England, however the timing is still uncertain. Ensembles show low probs of 6 hour QPF at or above 0.10" by Friday afternoon. Deterministic guidance varies between remaining dry through Friday to indicating at least some rain by the end of the day Friday. Ensembles also show PWAT values only from 0.20-0.40" going into Friday morning. Details will become clearer as we get closer to this event. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 12z TAF Update: Today: High confidence in trends but moderate on exact timing. MVFR-IFR in steady rain (at times mixed with wet snow in lower elevations to I-95), with periods of wet snow and visbys 1-4SM and minor slushy accumulation at ORH/BAF. Steadiest precip shield (liquid and wintry) moves northward from approx 13z south coast to 17z near the northern border with VT/NH, give or take an hour or two. Once that occurs, precipitation tapers off to an intermittent light rain/drizzle with areas of 4-6 SM mist into the afternoon. NE winds 15-20 kt with gusts 20-30 kt, highest near the coasts. Tonight: High confidence, though becomes moderate overnight. MVFR-IFR continues with stratus, fog/mist and drizzle or intermittent light rains. Another shield of steadier light rain moves westward from the ocean towards the eastern MA coast and could make it as far west as central MA/RI between 09-12z Sunday. NE winds around 15 kt with gusts 25-30 kt early shift to N around 8-12 kt with occasional gusts to 20 kt for the eastern MA coast. Sunday: Moderate confidence. MVFR-IFR with areas of drizzle and mist generally continues into Sunday, although there could be some VFR breaks late in the day at BAF/BDL. Best chance at steady light rain is eastern MA and into RI, although its western extent is still a little uncertain. Any rain near the eastern coasts should pull away late. N winds around 8-12 kt become NW and then decrease to 5-10 kt by afternoon. KBOS TAF...High confidence. KBDL TAF...High confidence. Outlook /Sunday Night through Wednesday/... Sunday Night: Mainly VFR, with local MVFR possible. Breezy. Monday: VFR. Monday Night: MVFR/IFR conditions possible. SHRA likely. Tuesday: Mainly VFR, with local MVFR possible. Breezy. Chance SHRA. Tuesday Night through Wednesday: Mainly VFR, with local MVFR possible. Breezy. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Through Sunday: High confidence. Gale Warnings on the southern waters and small craft advisories on the northern waters continue. On the southern waters, NE winds have increased into the 30-35 kt range and should continue to increase today. Buoy 44097 is reporting wave heights of 9.2 ft as of early this morning at 8 sec period, and mariners can expect rough sea state conditions with a pronounced east fetch. Areas of steady rain reducing visby to as low as 2 miles will continue into the afternoon before tapering off. Gale Warnings continue through 20z today to allow for gale force gusts to subside, and these will need to be downshifted to SCAs likely to be needed into the rest of the weekend. On the northern waters, NE winds increase to 30 kt today with seas building to 5-9 ft, along with rounds of steady rain this morning that taper off to mist/drizzle this afternoon. Winds may ease some tonight to around 20-25 kt, although may pick up again on Sunday to around 25-30 kt. Seas will remain elevated and rough through the weekend. Thus small craft advisories continue through Monday morning. Outlook /Sunday Night through Wednesday/... Sunday Night: Winds less than 25 kt. Local rough seas. Monday: Winds less than 25 kt. Areas of seas approaching 5 ft. Monday Night: Winds less than 25 kt. Rain showers likely. Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft. Chance of rain showers. Tuesday Night: Winds less than 25 kt. Local rough seas. Slight chance of rain showers. Wednesday: Low risk for Small Craft Advisory winds with gusts up to 20 kt. Local rough seas. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Winter Weather Advisory until 2 PM EDT this afternoon for MAZ002>004-008-009-026. RI...None. MARINE...Small Craft Advisory until 2 AM EDT Sunday for ANZ230. Gale Warning until 4 PM EDT this afternoon for ANZ231>235-237- 254>256. Small Craft Advisory until 4 PM EDT this afternoon for ANZ236. Small Craft Advisory until 8 AM EDT Monday for ANZ250. Small Craft Advisory until 2 AM EDT Monday for ANZ251. && $$ SYNOPSIS...Loconto/Hrencecin NEAR TERM...KJC SHORT TERM...Loconto LONG TERM...Hrencecin AVIATION...Loconto/Hrencecin MARINE...Loconto/Hrencecin