Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 300703 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 303 AM EDT MON MAR 30 2015 .SYNOPSIS... A COLD FRONT SWEEPS ACROSS NEW ENGLAND TODAY BRINGING A FEW RAIN AND SNOW SHOWERS. A FAST-MOVING AREA OF LOW PRESSURE PASSES SOUTH OF NEW ENGLAND TUESDAY NIGHT...POTENTIALLY BRINGING MORE LIGHT RAIN AND/OR SNOW SHOWERS. A MORE SIGNIFICANT STORM MAY APPROACH LATE THIS WEEK. && .NEAR TERM /THROUGH TODAY/... COLD FRONT CROSSING ONTARIO AND OHIO DURING THE NIGHT WILL MOVE EAST TODAY...CROSSING NEW ENGLAND DURING THE AFTERNOON. NORTHERN STREAM UPPER JET WILL BE IN POSITION DURING THIS TIME WITH THE LEFT EXIT REGION OVER SOUTHERN NEW ENGLAND. THIS WILL PROVIDE UPPER VENTING OVERLAID ABOVE LOW LEVEL CONVERGENCE OF THE FRONT. THIS SHOULD SUPPORT SHOWERS. A FEW LIGHT ONES IN CENTRAL NEW YORK OVERNIGHT MAY REACH OUR AREA THIS MORNING. THE BEST CHANCE FOR SHOWERS SHOULD COME ALONG AND AHEAD OF THE TRANSITING COLD FRONT. TIMING WOULD BE MIDDAY/EARLY AFTERNOON WEST AND MID AFTERNOON EAST. TEMPERATURE PROFILES INITIALLY FAVOR SNOW. BUT EXPECTED WARMING IN THE SOUTHERLY FLOW THIS MORNING SHOULD CHANGE THIS TO RAIN. ANY SNOW ACCUMULATION SHOULD BE LIMITED TO AN INCH OR LESS...MOSTLY LESS. PRESSURE FALLS OF 1MB/HR OR MORE LEAD THIS FRONT. EXPECT INCREASING SOUTHWEST WINDS DURING THE MORNING AND MIDDAY. PRESSURES RISE BEHIND THE FRONT BUT NOT AS STRONGLY. BUT COLD ADVECTION MAY INDUCE MIXING OF 25 KNOT GUSTS TO THE SURFACE AFTER THE FRONT MOVES THROUGH. && .SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/... TONIGHT... COLD ADVECTION CONTINUES TO SUPPORT MIXING INTO THE NIGHT. WINDS ABOVE THE SURFACE WILL BE 30-40 KNOTS...EXPECT SOME OF THIS TO MIX TO THE SURFACE IN GUSTS. BASED ON TEMPERATURES UPSTREAM...EXPECT LOWS IN THE MID 20S TO LOWER 30S. TUESDAY... WEAK HIGH PRESSURE WILL KEEP THE WEATHER DRY MUCH OF THE DAY. ANOTHER NORTHERN STREAM SHORTWAVE RACES SOUTHEAST ACROSS THE GREAT LAKES DURING THE DAY. THIS WILL SUPPORT A CLIPPER LOW THAT MOVES ACROSS THE MID ATLANTIC STATES DURING THE AFTERNOON. FORECASTS FROM THE 00Z MODEL SUITE ARE FARTHER NORTH THAN PREVIOUSLY WITH THE ECMWF FARTHEST SOUTH. ALL MODELS BRING SOME MEASUREABLE PCPN INTO CT BY EVENING...THE GFS COVERS AREAS SOUTH OF THE MASS PIKE...AND THE NAM HAS MEASURABLE PCPN EVERYWHERE. TEMPERATURE PROFILES SUGGEST RAIN MOST PLACES EXCEPT SNOW IN THE HILLS. TIMING OF THE PCPN WOULD BE AFTER 21Z. WE HAVE SHIFTED OUR POPS FARTHER NORTH WITH CHANCE POPS REACHING TO ALONG/SOUTH OF THE MASS PIKE BY 00Z. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... HIGHLIGHTS... * ALBERTA CLIPPER PASSES BY TO OUR SOUTH TUESDAY NIGHT * MODERATING...SPRING-LIKE TEMPERATURES LATE THIS WEEK * INCREASING CHANCES FOR PRECIPITATION SOMETIME DURING EASTER WEEKEND OVERVIEW... NORTHWEST FLOW TO START OVER THE REGION TUESDAY...LASTING INTO NEXT WEEKEND. SEVERAL SHORTWAVES WILL BE MOVING THROUGH THIS FLOW...ALLOWING FOR THE ACTIVE PATTERN TO CONTINUE. 29/12Z MODEL GUIDANCE IS IN GOOD OVERALL AGREEMENT...WITH SOME DISCREPANCIES WITH A CLIPPER-LIKE SYSTEM TUESDAY INTO WEDNESDAY...AND WITH A MORE SIGNIFICANT LOW PRESSURE LATE THIS WEEK. WILL CONTINUE TO A FAVOR A CONSENSUS APPROACH UNTIL THESE DETAILS OF THESE SYSTEMS COME INTO BETTER FOCUS. DETAILS... * TUESDAY NIGHT...MODERATE CONFIDENCE. NEXT SHORTWAVE WILL QUICKLY DIVE THROUGH THE FLOW FROM CANADA AND MOVE JUST SOUTH OF SOUTHERN NEW ENGLAND. THE MAJORITY 29/12Z GUIDANCE CONTINUES TO KEEP THIS STORM WELL TO OUR SOUTH...WITH ALMOST NO IMPACT AT ALL ON OUR WEATHER. THE CMC IS THE SLOWEST AND FARTHEST NORTH WITH THIS SYSTEM. THAT SAID...WILL TREND THIS PORTION OF THE FORECAST DRIER THAN PREVIOUS FORECASTS...WITH MINIMAL IMPACT ON SOUTHERN NEW ENGLAND. SINCE THE PASSAGE OF THIS STORM WILL BE AT NIGHT...THAT RAISES THE POSSIBILITY FOR MORE SNOWFALL IF TEMPERATURES LOWER FAST ENOUGH. WILL NEED TO CONTINUE TO WATCH THE TRENDS WITH THIS SYSTEM SINCE IT COULD PRODUCE A QUICK 1-2 INCHES OF SNOW ACROSS PORTIONS OF SOUTHERN NEW ENGLAND SHOULD THE TRACK BE FARTHER NORTH. * WEDNESDAY INTO THURSDAY...MODERATE CONFIDENCE. A WEAK RIDGE WILL BUILD BEHIND A CLIPPER SYSTEM WED INTO WED NIGHT. THIS WILL ALLOW FOR A STRONG HIGH PRESSURE TO BUILD OVER SOUTHERN NEW ENGLAND. LATEST TRENDS IN THE GUIDANCE IS FOR MOST OF THE DAY THURSDAY TO REMAIN DRY AS HIGH PRESSURE SLOWLY BREAKS DOWN. * THURSDAY NIGHT INTO SATURDAY...LOW CONFIDENCE IN TIMING. MODERATE CONFIDENCE IN PRECIPITATION OCCURRING. HIGH PRESSURE WILL MOVE OFFSHORE AS A LOW PRESSURE SYSTEM MOVES ACROSS SOUTHERN CANADA. THIS SYSTEM WILL DRAG A COLD FRONT ACROSS THE AREA EITHER THURSDAY NIGHT OR FRIDAY. IT APPEARS THERE COULD BE A FEW WAVES WHICH DEVELOP ALONG THIS FRONT...SO DECIDED TO NOT TRY TO TIME PRECIPITATION TO SPECIFICALLY. TEMPERATURES FRIDAY SHOULD BE ABOVE AVERAGE. TEMPERATURES WILL TURN COLDER BEHIND A FRONTAL PASSAGE BY SATURDAY OR SUNDAY. * SUNDAY...MODERATE CONFIDENCE. A WEAK TROUGH LINGERS ACROSS NEW ENGLAND. THE QUESTION WILL BE THE AMOUNT OF MOISTURE IT HAS TO WORK WITH. KEPT THIS PORTION OF THE FORECAST DRY...FOR NOW. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...HIGH CONFIDENCE THROUGH MONDAY NIGHT TODAY...VFR. BRIEF MVFR POSSIBLE IN SCATTERED RAIN AND SNOW SHOWERS. A COLD FRONT MOVES THROUGH FROM WEST TO EAST DURING MIDDAY TO MID-AFTERNOON. GUSTY WEST WINDS BEHIND THE FRONT MAY REACH 25-30 KNOTS. TONIGHT...VFR. GUSTY WEST WINDS BEHIND THE FRONT MAY REACH 25-30 KNOTS. TUESDAY...VFR. MVFR CIGS/VSBYS POSSIBLE ACROSS CT AND RI TOWARD EVENING. KBOS TAF...HIGH CONFIDENCE. KBDL TAF...HIGH CONFIDENCE. OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...HIGH CONFIDENCE. TUESDAY NIGHT...VFR FOR MOST OF THE PERIOD. MAY SEE MVFR SOUTH OF MASS PIKE IN RAIN/SNOW SHOWERS. WEDNESDAY INTO THURSDAY...VFR. FRIDAY...MAINLY VFR. SCATTERED MVFR IN SHOWERS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...TODAY THROUGH TUESDAY HIGH CONFIDENCE. TODAY...A COLD FRONT CROSSES NEW ENGLAND DURING THE AFTERNOON AND MOVES ACROSS THE WATERS TOWARD EVENING. SOUTHWEST WINDS WILL GUST TO NEAR 25 KNOTS IN ADVANCE OF THE FRONT. WEST WINDS TRAILING THE FRONT WILL GUST 25-30 KNOTS. SEAS WILL BUILD TO 5-7 FEET ON THE OUTER WATERS AND RHODE ISLANDS/BLOCK ISLAND SOUNDS. SMALL CRAFT ADVISORY CONTINUES ON ALL WATERS. TONIGHT...GUSTY WEST WINDS CONTINUE OVERNIGHT. SEAS OF 5-7 FEET LINGER ON THE OUTER WATERS AND RHODE ISLAND SOUNDS. SMALL CRAFT ADVISORY CONTINUES. TUESDAY...GUSTY WINDS WILL DIMINISH AS WEAK HIGH PRESSURE BUILDS BRIEFLY OVER THE WATERS. LINGERING SMALL CRAFTS ON THE OUTER WATERS. OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...MODERATE CONFIDENCE. TUESDAY NIGHT...QUICK-MOVING SYSTEM WILL MOVE OVER SOUTHERN WATERS. THIS WILL KEEP BOTH SEAS AND WINDS ABOVE SMALL CRAFT ADVISORY THRESHOLDS. WEDNESDAY INTO THURSDAY...HIGH PRESSURE WILL ARRIVE...ALLOWING FOR SEAS AND WINDS TO RELAX. FRIDAY...ANOTHER COLD FRONT APPROACHES THE WATERS...RESULTING IN INCREASING SOUTHWEST WINDS AND SEAS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 7 PM EDT THIS EVENING FOR ANZ231>234. SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 2 PM EDT THIS AFTERNOON FOR ANZ230-236. SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 9 AM EDT TUESDAY FOR ANZ235-237-256. SMALL CRAFT ADVISORY UNTIL 9 AM EDT TUESDAY FOR ANZ250-254-255. SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 5 PM EDT THIS AFTERNOON FOR ANZ251. && $$ SYNOPSIS...WTB/BELK NEAR TERM...WTB SHORT TERM...WTB LONG TERM...BELK AVIATION...WTB/BELK MARINE...BELK/RLG

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