Area Forecast Discussion
Issued by NWS Boston, MA

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594 FXUS61 KBOX 180730 AFDBOX Area Forecast Discussion National Weather Service Taunton MA 230 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/... 115 AM Update... Most of the steady precipitation has push SE of Nantucket at 06Z, though still seeing some spotty light rain and/or snow from about KGHG-KEWB south and east. Also noting some lingering patchy fog across portions of the Cape as well. However, should see drier air work in as NW winds pick up to 5-10 kt, though a bit higher across the mid and outer Cape. High pres ridging is building slowly E out of E NY state from the 1033 hPa center extending from western WV and KY/S OH at 06Z. this will continue to filter in the drier but colder air across the region. Clouds have been steadily clearing from the West, with mostly clear skies noted on the GOES-16 Fog and Nighttime Microphysics imagery which clearly show the back edge of the clouds. Lower cloud deck linger across E Mass into E RI, but should push offshore through the remainder of the night. Temps have fallen back to the teens across the CT valley, ranging to the lower-mid 30s where the clouds are lingering. As the clouds push offshore, the colder air will filter in through daybreak. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/... Today... Strong high pressure will build across the Mississippi Valley region pushing a coastal low off the Virgina coastline. Up here in the Northeast, flat ridge from the southern high pressure system will be in place. Continued westerly flow across the area as high temperatures will be near normal, reaching the upper 20s to mid 30s. Dry weather for the day with plenty of sunshine. Guidance is hinting at some ocean effect clouds moving in during the afternoon, as well as over the Berks from any LES. && .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 /07Z THURSDAY THROUGH MONDAY/... 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-IFR CIGS and local MVFR VSBYS in patchy fog from E RI into SE Mass will linger through around 09Z 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. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Short Term /through Friday/...High confidence. Coastal low will push into the Gulf of Maine tonight switching the winds to a more northwest direction. A few gusts to near 20 kts but overall winds will be below small craft criteria. Seas will remain at or above 5 feet through much of the period for the outer open waters. where Small Crafts will continue into Thursday evening. Have extended the Small Craft into the outer reaches of RI and BI sounds with 5 foot seas through mid morning Thursday. 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. && .HYDROLOGY... 1100 PM Update... 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. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 10 AM EST this morning for ANZ235- 237-251. Small Craft Advisory until 8 PM EST this evening for ANZ250- 254>256. && $$ SYNOPSIS...KJC NEAR TERM...Belk/EVT SHORT TERM...Dunten LONG TERM...KJC AVIATION...KJC/Dunten/EVT MARINE...KJC/Dunten/EVT HYDROLOGY... is the U.S. government's official web portal to all federal, state and local government web resources and services.