Area Forecast Discussion
Issued by NWS Boston, MA

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KBOX 292338 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 738 PM EDT FRI APR 29 2016 .SYNOPSIS... SHOWERS OVERNIGHT...MAINLY TOWARD SOUTHWEST NEW ENGLAND...WITH ONE MORE DAY OF QUIET WEATHER AND LINGERING HIGH PRESSURE FOR SATURDAY. UNSETTLED AND COOL WEATHER FOLLOWS FOR SUNDAY INTO MONDAY AS LOW PRESSURE TRACKS SOUTH OF NEW ENGLAND. A BRIEF DRYING TREND TUESDAY IS ONLY FOLLOWED BY MORE UNSETTLED WEATHER FOR LATE NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... NO MAJOR CHANGES TO THE FORECAST THIS EVENING. DID BRING THE FORECAST BACK IN LINE WITH OBSERVED TRENDS. SHOWERS ON RADAR MOSAIC HAVING A TOUGH TIME REACHING THE GROUND OVER SOUTHERN NEW ENGLAND. DEW POINT DEPRESSIONS OF 20+ DEGREES STILL NEED TO BE OVERCOME. ADJUSTED TIMING OF SHOWERS TO BE SLIGHTLY SLOWER. TONIGHT... S/W FOCUS OF WET WEATHER. POTENT VORTEX SWEEPING OUT TO SEA S OF NEW ENGLAND WITH FOCUS ALONG THE LEADING EDGE COLLOCATED WITH THE LEFT- FRONT QUADRANT OF AN ACCOMPANYING JET MAX. LOTS OF MOISTURE TO WORK WITH. LOOKING AT A DECENT SHOT OF RAIN OVER SW NEW ENGLAND POSSIBLY DRAGGING AS FAR N/E INTO CENTRAL AND SE NEW ENGLAND UP AGAINST HIGH PRESSURE OVER THE GULF OF MAINE. A CONSENSUS OF FORECAST GUIDANCE WITH MOS AND SREF TOUTED MORE SO GIVEN SUCH A MARGINAL EVENT AND WIGGLE ROOM. PALTRY AMOUNTS WITH UPWARDS OF A TENTH MAINLY OVER SW CT. AN EVENING INTO MIDNIGHT AFFAIR WITH AN ABUNDANCE OF CLOUDS AND TEMPERATURES HOLDING RELATIVELY STEADY. ITS AFTER MIDNIGHT TOWARDS SATURDAY MORNING THAT WE CLEAR OUT AND SUBSEQUENTLY TEMPERATURES DROP TO LOWS AROUND THE UPPER 30S. BREEZY SE FLOW EARLY BECOMING LIGHT WITH PASSAGE WHICH WITH CLEARING WILL AID WITH TEMPERATURES DROPPING. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... SATURDAY... IF YOU HAVE ANY OUTDOOR PLANS THIS DAY IS THE PICK OF THE WEEKEND. COMBINED DEEP LAYER SUBSIDENCE AND WEAK RIDGING ALOFT AHEAD OF AN ANTICIPATED DISTURBANCE FOR SUNDAY INTO MONDAY WILL MAKE FOR A GOOD DAY OF ANABATIC FLOW AS WINDS ARE LIGHT ALL THE WAY UP TO ROUGHLY H7. ANTICIPATING AN INTERIOR FLOW UP THE MOUNTAIN SLOPES WITH THE DEVELOPMENT OF CUMULUS ATOP. A LOCALIZED CONVERGENCE IF ALL COMES TOGETHER...SOME OF THE HIGH-RES GUIDANCE IS SPITTING OUT SOME WET WEATHER ALONG THE RIDGE OF THE BERKSHIRES. COULD NOT RULE OUT A SPRINKLE AS MOISTURE POOLS BENEATH A DRY-SUBSIDENCE INVERSION AROUND H8. OTHERWISE WARMING WELL INTO THE 60S PRIOR TO SOME THIN HIGH CLOUDS ENCROACHING FROM THE W BY EVENING. COOL ALONG THE SHORES WITH THE ONSHORE FLOW. WARMEST CONDITIONS IN THE CT RIVER VALLEY ESPECIALLY SPRINGFIELD-HARTFORD METRO. COULD NOT RULE OUT AN ISOLATED 70 DEGREE READING. SATURDAY NIGHT... MAIN QUESTION IS HOW EARLY WILL THE RAIN MOVE IN? CONSIDERING HIGH PRESSURE REMAINS INFLUENTIAL ACROSS THE GULF OF MAINE WITH RIDGING TO THE W ALBEIT WEAK AS TOP-DOWN MOISTENING PROCEEDS TO THE W PARENT WITH WEAK ISENTROPIC ASCENT AND FRONTOGENESIS WITH THE WARM FRONTAL APPROACH...CAN NOT RULE OUT SOME LIGHT SHOWER ACTIVITY ENCROACHING INTO THE CT RIVER VALLEY BY SUNDAY MORNING. COLUMN IS FAIRLY MOIST AND WITH THE WEAK LIFT PRESENT BASED ON SOUNDING ANALYSIS...IT IS ENOUGH TO GENERATE SOME WET WEATHER. SO LIKELY TO CHANCE POPS FROM THE BERKSHIRES INTO THE CT RIVER VALLEY. LOWERING AND THICKENING OF CLOUDS INTO MORNING WILL KEEP OVERNIGHT TEMPERATURES RATHER STEADY. MILDER TO THE W WITH THE THICKER BLANKET FOR LONGER...COOLER E WITH CLOUDS LESSER SO. LOWS AROUND THE LOW TO MID 40S. && .LONG TERM /SUNDAY THROUGH FRIDAY/... HIGHLIGHTS... * UNSEASONABLY COOL WITH PERIODS OF RAIN SUNDAY INTO MONDAY * DRYING TREND LIKELY TUE...POSSIBLY LINGERING INTO WEDNESDAY... ALONG WITH MILDER TEMPERATURES * MORE UNSETTLED WEATHER POSSIBLE LATE NEXT WEEK OVERVIEW... BELOW NORMAL CONFIDENCE IN THE DETAILS FOR THIS PORTION OF THE FORECAST...PARTICULARLY FROM WEDNESDAY ON. 29/12Z GUIDANCE SHOWING A SIMILAR OVERALL TREND...BUT THE TIMING AND SPATIAL DIFFERENCES GET RATHER PROFOUND LATE NEXT WEEK. ENSEMBLES SHOWED A LARGE ENVELOPE OF SOLUTIONS...LEADING TO THIS LOW CONFIDENCE FORECAST. UNSETTLED WEATHER EXPECTED IN BURSTS NEXT WEEK. ONE LOW PRESSURE PASSES US BY ON MONDAY...WITH ANOTHER SYSTEM SOMETIME LATE NEXT WEEK. NOT EXPECTING A TOTAL WASHOUT...BE WE COULD SEE MANY PERIODS OF RAIN BETWEEN LATE WEDNESDAY AND FRIDAY...IT THIS SECOND LOW PRESSURE SLOWS ITS EASTWARD PROGRESS. SUNDAY INTO MONDAY...MOST OF THIS PERIOD STILL LIKELY TO BE COOL AND WET. INITIAL SHOT OF RAIN MOVES ACROSS THE REGION DURING SUNDAY FROM WEST TO EAST. RAIN MAY HOLD OFF UNTIL SUNDAY AFTERNOON ACROSS EASTERN NEW ENGLAND. A SECOND PERIOD OF RAIN IS EXPECTED SUNDAY NIGHT INTO MONDAY AS A LOW PRESSURE TRACKS SOUTH OF OUR REGION. 29/12Z GFS STILL LOOKS TO BE OVERDONE WITH ITS RAINFALL AMOUNTS. LOW LEVEL EASTERLY FLOW WILL KEEP TEMPERATURES WELL BELOW NORMAL SUNDAY INTO MONDAY. TUESDAY INTO WEDNESDAY... WEAK HIGH PRESSURE SHOULD BRING MAINLY DRY WEATHER TUESDAY WITH TEMPS REBOUNDING TO NEAR SEASONABLE NORMS AWAY FROM THE IMMEDIATE COAST. DRY AND SEASONABLE CONDITIONS MAY PERSIST INTO WEDNESDAY... BUT NOT SO CONFIDENT. WHILE THE PRIMARY MID LEVEL TROUGH AXIS REMAINS BACK ACROSS GREAT LAKES...MOST OF THE MORE RELIABLE GUIDANCE NOW SHOWING A DECENT SHORTWAVE HEADING OUR WAY FROM THE MID ATLANTIC STATES. THIS WAVE COULD BE STRONG ENOUGH...TO TRIGGER SOME SHOWERS...IF ENOUGH MOISTURE COMES WITH IT. GFS IS AGGRESSIVE IN DOING SO...WHILE THE ECMWF SOLUTION IS SLOWER TO BRING SUFFICIENT MOISTURE NORTH. THURSDAY AND FRIDAY...STILL LOOKING LIKE UNSETTLED WEATHER AND COOLER TEMPS WILL RETURN AS MID LEVEL TROF AMPLIFIES ACROSS NE WITH POTENTIAL FOR ANOTHER COASTAL WAVE TO THE SOUTH OF NEW ENGLAND WITH EASTERLY FLOW. LARGE DIFFERENCES IN THE MID LEVEL FLOW...WITH THE GFS KEEPING ITS MID LEVEL CUTOFF NORTH OF THE GREAT LAKES...AND THE ECMWF HAVING A MUCH WEAKER CUTOFF OVER THE CAROLINAS. HAVE LOW CONFIDENCE IN THE DETAILS. AT PRESENT...THINKING THURSDAY WOULD BE THE MORE LIKELY DAY FOR WET WEATHER. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE. TONIGHT... BKN-OVC LOW END VFR CIGS WITH -RA S/W EVENING INTO MIDNIGHT... CLEARING TOWARDS MORNING. DOMINANT E FLOW. SATURDAY... SCT-BKN LOW-END VFR CIGS ACROSS THE INTERIOR MAINLY OVER THE HIGH TERRAIN. DOMINANT E FLOW. SATURDAY NIGHT... BKN-OVC CLOUDS LOWERING TOWARDS MORNING DOWN TO LOW-END VFR WITH A LOW RISK OF MVFR. -RA FOR TERMINALS MAINLY W OF ORH. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK /SUNDAY THROUGH WEDNESDAY/... SUNDAY INTO MONDAY...HIGH CONFIDENCE ON TRENDS WITH DETERIORATING CONDITIONS TO MVFR AND LOCALIZED IFR POSSIBLE IN PERIODS OF RAIN. TUESDAY...MODERATE CONFIDENCE. DRYING TREND WITH VFR AND LIGHT WINDS. WEDNESDAY...MODERATE CONFIDENCE. MAINLY VFR. BRIEF MVFR IN SCATTERED SHOWERS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE. TONIGHT... INCREASING E/SE FLOW AHEAD OF AN APPROACHING LOW OUT OF THE GREAT LAKES INTO THIS EVENING...EXITING TOWARDS SATURDAY MORNING. AN ISOLATED GUST UP TO 25 KTS NOT OUT OF THE QUESTION. SEAS BUILDING POTENTIALLY UP TO 5 FEET ON THE S OUTER WATERS BUT WILL HOLD AT 4 FEET. SATURDAY INTO SATURDAY NIGHT... CONTINUED E/SE FLOW THOUGH NOT AS BREEZY WITH GUSTS REMAINING BELOW 20 KTS. GOOD BOATING WEATHER. CLOUDS ON THE INCREASE LATE TOWARDS SUNDAY MORNING. OUTLOOK /SUNDAY THROUGH WEDNESDAY/... SUNDAY INTO MONDAY...MODERATE CONFIDENCE. INCREASING EASTERLY WINDS SUNDAY AFTERNOON AND NIGHT...THEN SHIFTING TO NORTH DURING MONDAY AS LOW PRESSURE MOVES INTO THE GULF OF MAINE. A PERIOD OF EASTERLY 25 KT PLUS GUSTS POSSIBLE SUN AFTERNOON AND EVENING... AND AGAIN DURING MONDAY AS WINDS SHIFT TO NORTH. ROUGH SEAS GIVEN THE LONG ENE FETCH. VSBYS REDUCED AT TIMES IN RAIN AND PATCHY FOG. TUESDAY...HIGH CONFIDENCE. LIGHT WINDS BUT LEFTOVER ROUGH SEAS LIKELY ACROSS THE EASTERN WATERS FROM ENE SWELLS. SEAS DIMINISHING. WEDNESDAY...MODERATE CONFIDENCE. INCREASING SOUTHEAST WINDS DURING THE AFTERNOON WILL LEAD TO BUILDING SEAS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...BELK/SIPPRELL NEAR TERM...BELK/SIPPRELL SHORT TERM...SIPPRELL LONG TERM...BELK AVIATION...BELK/SIPPRELL MARINE...BELK/SIPPRELL

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