Area Forecast Discussion
Issued by NWS Boston, MA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KBOX 180946 AFDBOX Area Forecast Discussion National Weather Service Taunton MA 446 AM EST Thu Jan 18 2018 .SYNOPSIS... Dry and seasonably cold conditions today and Friday, then a warming trend this weekend with continued dry weather. A storm system will affect the region sometime Monday night into Tuesday with mostly rain and coastal wind, but there is a risk of some mix/ice across the interior. Blustery and colder weather follows next Wednesday. && .NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
Last of lower clouds across SE Mass and Cape Cod/islands at 09Z as seen on latest GOES-E Fog and Nighttime Microphysics products very well. Noting CIGS in the 1-2Kft range, though still noting clouds continuing to move NE across those areas so may take some time for them to finally clear out. Further N and W, skies were mainly clear with just a few wisps of high clouds. Drier air continues to filter in as dewpoints have dropped to the single digits and teens across most areas, but are holding in the 20s from about a KBVY-KPVD-KBID line eastward to around freezing across the Cape and islands. Moisture from the passing low is holding SE of the southern Nantucket coast, but should push offshore as the ridge builds E today. With the clear skies and light winds, temps have nosedived across portions of the CT valley, with readings in the single digits at KORE, KBAF and KCEF at 09Z, and down in the teens across south central and SW Mass into N CT. H85 temps are holding at around 0C across SE Mass and RI, dropping to -4C across N central and NW Mass this morning, but should fall as the low moves away. Expect temps to only reach the lower-mid 20s across the E slopes of the Berkshires, ranging to the lower-mid 30s across the coastal plain under mainly sunny skies. W-NW winds may gust up to 10-15 kt mainly across central and eastern areas, which would result in wind chill values down in the 20s.
-- End Changed Discussion --
&& .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
-- Changed Discussion --
Tonight and Friday... As the H5 cutoff low finally pushes offshore tonight, NW winds will diminish as the surface ridges builds E across the region. Skies will remain mainly clear early. Noting another H5 short wave in the fast flow out of the Great Lakes, which will cross the region around or after midnight. Little if any moisture with this system, and what there is should pass across northern New England overnight. Will see mid level clouds move across, then start to lift NE toward daybreak. May see some brief lower clouds across portions of NW Mass during the pre dawn hours. Expect lows mainly in the teens, ranging to the lower-mid 20s along the coast. The short wave will quickly push to the Maritimes Friday morning, taking the clouds with it though some scattered high clouds may linger across central and N Mass during the day. Winds will be mainly W, so expect temps to run close to seasonal normals, topping off in the upper 20s to lower 30s across central and western areas, ranging to the mid 30s along the coast.
-- End Changed Discussion --
&& .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Highlights... * Dry and mild this weekend * Another storm will bring mostly rain and gusty coastal winds Mon night/Tue with a risk of some interior mixed precip/ice Mild and dry conditions expected this weekend under zonal flow and rising heights. Temps should reach well into the 40s both days with the chance of a few 50 degree readings Sat. It will be a bit breezy Sat with potential for 25-35 mph SW gusts near the coast which will temper the milder temps but less wind Sunday. Some light precip in the form of rain/snow showers possible Mon in the developing warm advection pattern, but models have trended a bit slower with timing of next storm, with greatest impact likely sometime late Mon night into Tue. Deep mid level trough/low approaching from the west is expected to lift NE across the Gt Lakes and into SE Canada. A robust pre-frontal low level jet will likely bring a decent slug of rain to SNE with potential for heavy rainfall and strong coastal wind. PWAT and low level wind anomalies are 2+ SD which is pretty good for a day 5-6 forecast. Exact timing of the rain and wind is uncertain and there also remains enough uncertainty with thermal profile that some interior mix/ice possible at the onset. ECMWF is more robust with the colder air but it will take awhile for these finer details to be resolved. As storm exits, blustery and colder weather will likely follow next Wednesday. && .AVIATION /09Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Friday/...High confidence. Through 12Z...VFR across central and western areas into NE Mass. Lingering MVFR CIGS and local MVFR VSBYS in patchy fog across SE Mass will linger through around 10Z or so then should slowly improve. Today...VFR. May see some lingering MVFR CIGS across the mid and outer Cape and well as KACK through 14Z before improving. NW winds gusting up to 20 kts along the immediate S coast, Cape Cod and the islands this afternoon. Tonight...Mainly VFR conditions. May see some local MVFR CIGS at times across the outer Cape and E slopes of the Berkshires on N-NW winds. Friday...VFR conditions for most areas, but may see MVFR CIGS linger across the E slopes of the Berkshires through midday. KBOS Terminal...High confidence in TAF. KBDL Terminal...High confidence in TAF. Outlook /Friday Night through Monday/... Friday Night: VFR. Breezy. Saturday: VFR. Windy with gusts to 30 kt. Saturday Night: VFR. Breezy. Sunday through Sunday Night: VFR. Monday: MVFR/IFR conditions possible. Chance SHRA.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Friday/...High confidence. Expect NW winds around 10 kt or so today, then will back to W and remain light tonight and Friday. Seas will continue at around 5 ft across the open waters through today at least. They should subside on the eastern outer waters late tonight, but will continue on the southern waters. Small Craft Advisories remain in effect there. Outlook /Friday Night through Monday/... Friday Night: Low risk for Small Craft Advisory winds with local gusts up to 30 kt. Seas up to 5 ft. Saturday: Low risk for gale force winds with gusts up to 35 kt. Rough seas up to 11 ft. Saturday Night: Low risk for Small Craft Advisory winds with gusts up to 30 kt. Local rough seas. Sunday: Winds less than 25 kt. Seas locally approaching 5 ft. Sunday Night: Winds less than 25 kt. Monday: Winds less than 25 kt. Seas locally approaching 5 ft.
-- End Changed Discussion --
&& .HYDROLOGY...
-- Changed Discussion --
A Flood Warning remains in effect for the Connecticut River at Middle Haddam, where ice jams are causing river fluctuations. Cold conditions will persist through Thursday which will limit additional runoff. Continued ice jams will remain on some of the rivers. There will be some increase of snow pack across interior southern New England as well. For details on specific area rivers, including observed and forecast river stages, please visit the Advanced Hydrologic Prediction Service (AHPS) graphs on our website.
-- End Changed Discussion --
&& .BOX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 6 AM EST Friday for ANZ250. Small Craft Advisory until 6 PM EST Friday for ANZ254>256.
-- End Changed Discussion --
&& $$ SYNOPSIS...KJC/EVT NEAR TERM...EVT SHORT TERM...EVT LONG TERM...KJC AVIATION...KJC/EVT MARINE...KJC/EVT HYDROLOGY...Staff

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.