Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 280953 AFDBOX Area Forecast Discussion National Weather Service Taunton MA 553 AM EDT Fri Oct 28 2016 .SYNOPSIS... Low pressure over eastern Massachusetts early this morning will continue to intensify as it moves slowly offshore today. This will result in a drying trend, but windy conditions as well. Mild temperatures and less wind will return on Saturday as a high pressure ridge moves across the area. Low pressure approaches Sunday with a period of rain possible in the afternoon and evening. High pressure delivers dry but cooler weather Monday. Temperatures moderate Tuesday as the high moves offshore with Wednesday likely being the mildest day next week. A dry cold front ushers in a cooler airmass late next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Strong SE winds moved across S coastal Mass earlier this morning as strengthening low pressure pushed across the region. Noted very strong pressure falls overnight, on the order of 5-6 mb/3 hrs. This allowed strong low level jet to mix down along with the areas of heavy rainfall that moved across, bringing wind gusts up to 58 mph in East Falmouth and 51 mph in the West Island section of Fairhaven. Have issued Public Information Statement with the wind gusts as well as the snow that fell on Thursday night. As for today, it will be a transition day. The low pressure will continue to deepen as it moves into Massachusetts Bay and the western Gulf of Maine this morning. Short range models continue to signal an associated H5 cutoff low with the surface feature, which will be slow to move E. A second short wave will rotate around this upper level feature this afternoon, which will bring another surge of strong N-NW winds across the eastern waters as well as Cape Cod and the islands. Winds will pick up again toward evening, so have extended the wind advisory into this evening with the additional surge of strong winds across the Cape and islands. Have kept the wind advisory through mid morning across east coastal Mass, while canceling the remaining areas of interior SE Mass and SE RI as the winds there have diminished as the low moved away earlier this morning. This short wave may also bring some patchy light rain toward evening across portions of Cape Ann and outer Cape Cod. Lingering showers continue across central and eastern Mass as the H5 cutoff low moves across. This will also cause clouds to linger through most of the day. Looks like there should be some breaks in the clouds across western Mass into N central CT and south coastal RI as the influence of the upper low loosens its grip there. Expect today`s highs to occur this morning, ranging from 40-45 across the higher inland terrain up to the mid and upper 50s across east coastal Mass. Readings will remain steady or slowly fall from midday onward as cooler air works in. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... Tonight...Any patchy light rain that falls across Cape Ann and Cape Cod/Nantucket this evening will rotate offshore by around midnight as the short wave and associated H5 cutoff low exit to the Gulf of Maine. The winds will also diminish. A weak high pressure ridge will build across the region overnight. Skies will average out partly cloudy, though more clouds may linger across N Mass. Overnight lows will fall back to the 30s away from the coast, ranging to the lower-mid 40s along the immediate shoreline. Saturday...The high pressure ridge will push east, with light NW winds to back around to SW which will allow seasonable temperatures to return. Another low will move across northern New England during the day, with a trailing cold front that will begin to approach. Clouds will increase during the day, but any light rain should remain north of the region. Expect temperatures to top off in the 55-60 degree range. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Updated 405 am... Highlights... * Seasonable much of the time...coolest Mon and warmest Wed * Chance of rain Sun aftn/evening...otherwise mainly dry Sat night and Sunday... Weak cold front moves across the area. Deep layer moisture and lift are other than a spot shower mainly dry weather prevails Sat night. WAA in prefrontal airmass yields mild conditions Sat night with mins only dropping into the 45-50 deg range. Normal low temps should be in the upper 30s to low 40s range. Breezy Sat evening with southwest winds 15-25 mph...strongest winds along the coast and high terrain. Sunday...still amplitude differences among the models regarding northern stream short wave inducing a wave of low pres over PA/NJ/NYC area on the frontal boundary passing our region Sat night. However good agreement on the timing with all guid including the 00z GEFS and 00z EC on rain holding off until Sun afternoon or evening across most of CT/RI and MA. Remaining mild Sunday as cooler air lags way to the north of the frontal boundary draped along our south coast. Next Week... Monday...Northern stream short wave and associated frontal wave exit east of our longitude Sun night and replaced by modest CAA Monday along with 1026 MB high over the eastern Great Lakes building east into New England. So dry weather Monday but cooler with highs 50- 55...upper 40s higher terrain. Normal high still about 55-60. A chilly north wind in the morning then diminishing in the afternoon as high pres crest over the region. Tuesday...chilly start to the day with high pres over the area...however high pres drifts offshore with return flow for the afternoon. Thus temps will moderate to seasonal levels Tue aftn with highs 55-60. Low risk of a spot shower Tue night with weak front approaching from the northwest. Mins Mon ngt/Tue am were derived from the colder MOS guid. Wednesday...could be the pick of the week with WAA ahead of approaching weak cold front. After a mild Tue ngt with mins only 45- 50...highs Wed aftn could make a run at 70! Golf? Other than a spot shower a dry frontal passage is likely as models suggest deep layer moisture and lift lacking. Thursday...a cooling trend likely develops as both EPS and GEFS ensembles indicate northern stream lowering heights across the northeast states. && .AVIATION /09Z FRIDAY THROUGH TUESDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Saturday/... Through 12Z...Moderate confidence. Areas of IFR-LIFR CIGS/VSBYS across the interior will slowly improve by around 12Z, while MVFR to low end VFR CIGS and mainly VFR VSBYS will remain along the coast. Today...High confidence in trends, lower on timing. Leftover MVFR-IFR CIGS will improve from S-N this morning, but will linger across central and N Mass. MVFR CIGS may return to E coastal Mass during the afternoon. MVFR-IFR VSBYS will improve by midday. Winds shift to W-NW and briefly diminish this morning, then will increase again this afternoon especially along the immediate E coast, Cape Cod and the islands. Tonight...High confidence. MVFR to low end IFR CIGS lingering across central and eastern Mass into N RI/NE CT through 02Z-04Z, then should improve to VFR. Expect VFR VSBYS. N-NW winds gusting up to 30-35 kt across outer Cape Ann as well as Cape Cod and the islands through 04Z-06Z, then should diminish. Saturday...High confidence. VFR conditions. Low end VFR CIGS will push into central and N Mass during Saturday afternoon. KBOS TAF...High confidence in trends, lower confidence in timing. KBDL TAF...High confidence in trends, lower confidence in timing. Outlook /Saturday Night through Tuesday/... Updated 405 AM... Saturday night - Sunday...moderate confidence. VFR likely Saturday night along with dry weather. Then MVFR possible Sunday afternoon and evening in a period of rain. Monday-Tuesday...High confidence. VFR, with mainly dry weather. && .MARINE... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Saturday/...High confidence. Through Today...Leftover gale force gusts across the eastern waters will briefly diminish this morning. Another surge of strong winds pushes across outer across the eastern waters, with gale force N-NW winds developing by evening. Gale warnings remain on the eastern waters as well as the southern outer waters. Have converted near shore southern waters over to small crafts W of Cape Cod and Marthas Vineyard as well as Boston Harbor and Narragansett Bay. Strong SE winds earlier this morning brought seas up to 8-11 ft, which will slowly subside but remain above 5 ft this afternoon. Tonight...N-NW winds gust up to around 35 kt early tonight across the eastern waters including Cape Cod Bay and Nantucket Sound, then will diminish. Gales will likely lower to Small Crafts late tonight. Seas will take longer to subside, especially on the eastern waters. Saturday...NW winds will diminish in the morning before backing to SW in the afternoon. Seas will remain around 5 ft on the eastern waters early, but should subside. Outlook /Saturday Night through Tuesday/... Updated 405 AM... Saturday night - Sunday...moderate confidence. Southwest winds 15 to 20 kt with gusts up to 25 kt possible Sat night. Mainly dry weather and good vsby. Then Sunday light WNW as weak cold front boundary sags south across the waters. Then winds become ENE 15 to 20 kt as wave of low pres tracks along the front from west to east. Vsby will lower to 1-3 miles in rain Sunday afternoon and evening...then improving overnight. Monday-Tuesday...high confidence. North winds Monday 15-20 kt with gusts up to 25 kt possible. Could be a few ocean effect rain showers. North winds will increase seas across the eastern MA waters. Diminishing winds Mon ngt into Tue morning as high pres crest over the region. Then winds becoming south late Tue. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...Wind Advisory until 10 AM EDT this morning for MAZ007-014>016- 019. Wind Advisory until 11 PM EDT this evening for MAZ022>024. RI...None. MARINE...Gale Warning until 3 AM EDT Saturday for ANZ231-232. Small Craft Advisory until 3 AM EDT Saturday for ANZ233-234. Small Craft Advisory until 2 AM EDT Saturday for ANZ230. Small Craft Advisory until midnight EDT tonight for ANZ236. Small Craft Advisory until 4 AM EDT Saturday for ANZ235-237. Gale Warning until 5 AM EDT Saturday for ANZ250-254-255. Gale Warning until 1 AM EDT Saturday for ANZ251. Gale Warning until midnight EDT tonight for ANZ256. && $$ SYNOPSIS...Nocera/EVT NEAR TERM...EVT SHORT TERM...EVT LONG TERM...Nocera AVIATION...Nocera/EVT MARINE...Nocera/EVT is the U.S. government's official web portal to all federal, state and local government web resources and services.