Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 240012 AFDBOX Area Forecast Discussion National Weather Service Taunton MA Issued by National Weather Service UPTON NY 712 PM EST Tue Jan 23 2018 .SYNOPSIS... Lingering rain showers come to an end this evening as drier air works into the region behind a cold front. Blustery, dry and colder weather follows Wednesday through Friday, then a warming trend next weekend. A cold front may bring showers next Sunday or Monday. && .NEAR TERM /THROUGH WEDNESDAY/... Heavy rain/isolated convection has exited the region. A few showers may linger into the first part of the evening but that is about it. Have let the wind advisory expire at 6 pm for southeast New England as the low level jet shifts east of the region. Current temps were still in the lower to middle 30s across a few areas of interior MA but well into 50s along the coastal plain late this afternoon. Should see temps across the interior briefly rise behind the cold front over the next few hours as inversion mixes out. This will take care of any lingering icy roads/walkways across north central and northeast MA. Otherwise...dry weather along with partial clearing behind the cold front later this evening. Low temps by daybreak will fall back into the upper 20s to the middle 30s. && .SHORT TERM /WEDNESDAY NIGHT/... Wednesday... A west northwest flow of more seasonable temperatures will be working back into the region on Wednesday. High temps will not recover too much...generally remaining in the 30s to near 40 across parts of the coastal plain. Should be at least partial sunshine...but do expect some strato-cumulus clouds that will be focused across the interior. West to northwest winds will gust to between 25 and 30 mph at times. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Highlights... * Dry but cooler weather for the rest of the work week * Above average temperatures for Saturday and Sunday * Next shot of wet weather will be around Sun/Mon Overview... 12z guidance is in general agreement with the upcoming medium and long range. Progressive pattern over the region as ongoing upper level trough will push offshore as mid-level ridge builds into the area by the weekend. For the end of the period, still some uncertainty regarding the timing and amplitude of the upper level trough moving from the Northern Plains towards the East Coast Sun into Monday. GFS continues to be on the faster side of the envelope compared to the EC and UKMET. If the guidance continues to trend towards the slower envelope, than there is the potential for a more significant surface low to develop. This could result in warmer temps for the weekend, and heavier rainfall. If it is weaker, than cannot rule out some trapped cold air resulting in p-type issues. Still a lot of uncertainty and will trend towards a blend of the guidance until details can be sorted. Wednesday night into Friday...High confidence. Building high pressure across the southeast will build across the US East Coast resulting in dry weather through the period. Still some thermal gradients in the mid-levels as upper level shortwave passes through on Thursday. This will result in a breezy but chill day. Temperatures will still be in the 30s on Friday, but with less winds should make it feel warmer. Some mid-level moisture around 850-700mb will help bring in some clouds but overall a pleasant January day is on tap. Saturday into Monday...Moderate confidence. Subtropical ridge will build across the US East Coast over the weekend as northern stream system approaches the Northeast. All guidance as well as the ensembles are indicating precipitation for the area. Biggest uncertainty is the amount, exact timing and if all precip will be liquid. Current forecast is an ongoing blend of the guidance with a trend towards the UKMET and EC. Thus expect precipitation to move into the area on Sunday as mostly rain and temperatures will be well above average thanks to southerly LLJ. If precip lingers into Monday, CAA behind the system could switch any precip to snow, but overall confidence is low that this will occur. Will need better guidance to see this potential. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Wednesday Night/... Tonight...low to moderate confidence this evening, then moderate to high confidence overnight. Conditions improve to VFR this evening, exact timing could be off +/- 1=2 hours in TAFs. Some marginal MVFR cigs may work back into the region after midnight in the CAA pattern...mainly across the interior. Wednesday...Moderate to high confidence. Mainly VFR but some brief marginal MVFR cigs possible for a time in the interior. WNW winds gusts of 20 to 30 knots. KBOS Terminal...Moderate to high confidence in TAF. KBDL Terminal...Moderate to high confidence in TAF. Outlook /Thursday through Sunday/... Wednesday Night through Thursday: VFR. Breezy. Thursday Night: VFR. Windy with local gusts to 30 kt. Friday: VFR. Breezy. Friday Night: VFR. Saturday: VFR. Windy with gusts to 30 kt. Saturday Night: Mainly MVFR, with areas VFR possible. Breezy. Chance RA. Sunday: Mainly MVFR, with areas IFR possible. Breezy. RA likely. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Wednesday Night/... Tonight...High confidence. Have converted the Gale Warnings to SCA with LLJ pushing east of the waters. May see a temporary lull in the winds...but they will pick back up after midnight with WSW gusts of 25 to 30 knots developing in the cold air advection pattern. Wednesday...High confidence. WNW wind gusts of 25 to 30 knots in the cold air advection pattern. SCA headlines will be needed for most waters. Outlook /Thursday through Sunday/... Wednesday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft. Thursday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Seas up to 5 ft. Chance of freezing spray. Thursday Night: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Areas of rough seas. Chance of freezing spray. Friday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas locally approaching 5 ft. Friday Night: Winds less than 25 kt. Saturday: Low risk for Small Craft Advisory winds with gusts up to 30 kt. Local rough seas. Saturday Night: Winds less than 25 kt. Local rough seas. Chance of rain. Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 6 PM EST Wednesday for ANZ230>237- 250-251-254>256. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE... is the U.S. government's official web portal to all federal, state and local government web resources and services.