157  
FXUS61 KBOX 101958  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
358 PM EDT TUE JUL 10 2018  
   
SYNOPSIS
 
 
AN APPROACHING COLD FRONT WILL TRIGGER SCATTERED SHOWERS AND  
THUNDERSTORMS INTO THIS EVENING. A FEW STRONG STORMS ARE  
POSSIBLE ACROSS THE INTERIOR. TROPICAL STORM CHRIS IS EXPECTED  
TO INTENSIFY INTO A HURRICANE BY WEDNESDAY, AND PASS WELL  
SOUTHEAST OF NANTUCKET WEDNESDAY. HIGH PRESSURE WILL BUILD OVER  
THE REGION THURSDAY AND FRIDAY, RESULTING IN MAINLY DRY WEATHER  
ALONG WITH SEASONABLE TEMPERATURES AND COMFORTABLE HUMIDITY. A  
RETURN TO HOT WEATHER IS EXPECTED LATER THIS WEEKEND INTO EARLY  
NEXT WEEK. WHILE A FEW THUNDERSTORMS CANNOT BE RULED OUT THIS  
WEEKEND INTO EARLY NEXT WEEK, DRY WEATHER LOOKS TO DOMINATE THE  
MAJORITY OF THE TIME.  
 

 
   
NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/
 
 
TEMPERATURES AT 850MB ARE NEAR 19C AND ARE MIXING DOWN TO THE  
SURFACE WHERE SITES ARE SEEING TEMPS NEAR OR SURPASSING 90F. THE  
APPROACHING COLD FRONT IS CURRENTLY JUST SE OF THE CANADIAN/NEW  
YORK BORDER WHERE A LINE OF CU AND A FEW ISOLATED THUNDERSTORMS  
ARE POPPING UP.  
 
LOOKING AT SEVERAL HI-RES MODELS, THE POTENTIAL FOR ANY STRONG  
TO SEVERE THUNDERSTORMS LOOKS TO BE DIMINISHING ACROSS SNE. DRY  
AIR ALOFT DOESN'T SEEM TO MOVE OUT OF THE REGION UNTIL 00Z AND  
GIVEN THAT CURRENT DEWPOINTS ACROSS THE REGION ARE IN THE LOW  
60S AND MID 50S, SHOWERS AND THUNDERSTORMS WILL HAVE A DIFFICULT  
TIME FORMING WITH THE LACK OF MOISTURE. IN ADDITION, WESTERLY  
WINDS WILL PROVIDE MINIMAL TO NO SURFACE CONVERGENCE. THE BEST  
CHANCE FOR ANY THUNDERSTORMS DEVELOPING WILL BE ON THE EASTERN  
SLOPES OF THE BERKSHIRES AND THE WORCESTER HILLS DUE TO  
UPSLOPING WINDS. HIGHER TERRAIN IS ALSO COLOCATED WITH THE  
STRONGEST SHEAR AND INSTABILITY. THE MAIN TIME FRAME FOR STORMS  
LOOKS TO BE BETWEEN 21Z AND 02Z.  
 
ISOLATED SHOWERS AND THUNDERSTORMS MAY CONTINUE INTO THE  
EVENING, WHEN THE BEST SYNOPTIC FORCING, SHEAR, COOLING TEMPS  
ALOFT, AND INSTABILITY ARRIVE IN SNE. SOME HEAVIER SHOWERS ARE  
POSSIBLE LATE TONIGHT WHERE PWATS OVERNIGHT REACH UP 1.75" AND K  
INDICIES ARE UP TO 38.  
 
TEMPS ARE EXPECTED TO REMAIN IN THE 60S OVERNIGHT, BUT IF  
CLOUDS ASSOCIATED WITH THE COLD FRONT CLEAR OUT BEFORE SUNRISE,  
SOME RADIATIONAL COOLING IS POSSIBLE, ESPECIALLY IN WESTERN MA  
ACROSS THE HIGHER TERRAIN.  
 
ACK MAY SEE A BRIEF PERIOD OF FOG JUST BEFORE SUNRISE TOMORROW  
AS SW WINDS DIMINISH AFTER THE FRONTAL PASSAGE AND AN INVERSION  
REMAINS OVERHEAD.  
 

 
   
SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/
 
 
WEDNESDAY...  
 
COLD FRONT WILL BE SITTING JUST EAST OF NANTUCKET COME SUNRISE  
TOMORROW MORNING WITH SOME POSSIBLE LINGERING SHOWERS AND  
THUNDERSTORMS ACROSS RI AND SE MASS.  
 
AS THE FRONT MOVES OFFSHORE AND INSTABILITY ERODES THROUGHOUT  
THE MORNING, ANY LINGERING SHOWERS AND THUNDERSTORMS WILL  
DISSIPATE ACROSS SE NEW ENGLAND.  
 
THERE'S A SMALL CHANCE FOR ISOLATED SHOWERS TOMORROW AFTERNOON  
ACROSS NORTHERN CT AND CENTRAL MA GIVEN CYCLONIC FLOW AND  
COOLING TEMPS ALOFT, BUT THESE WILL LIKELY BE SHORT LIVED WITH  
VERY LITTLE IMPACT.  
 
TROPICAL STORM CHRIS IS EXPECTED TO PASS 300 MILES TO OUR SE,  
RESULTING IN HIGH SURF AND DANGEROUS RIP CURRENTS ALONG SOUTH  
COASTAL BEACHES. HIGH SURF ADVISORIES MAY BE NEEDED.  
 
WEDNESDAY WILL BE MUCH COOLER THAN TODAY AS WINDS OUT OF THE NE  
KEEP THE REGION IN THE MID 70S. THE WARMEST TEMPERATURES ARE  
LIKELY TO BE IN THE CONNECTICUT RIVER VALLEY WHERE HARTFORD MAY  
SEE 80 DEGREES. BEHIND THE COLD FRONT, HUMIDITY WILL DECREASE AS  
DEWPOINTS WILL BE IN THE MID TO UPPER 50S ACROSS THE REGION.  
 
WEDNESDAY NIGHT...  
STRONG NE WINDS AND HIGH SURF WILL CONTINUE INTO THE EVENING  
AS TS CHRIS DEPARTS THE REGION AND CONTINUES MOVING NE. SKIES  
WILL BE MOSTLY CLEAR AS A 1024MB HIGH BUILDS INTO NEW ENGLAND,  
ALLOWING TEMPERATURES TO COOL INTO THE 50S OVERNIGHT.  
 

 
   
LONG TERM /THURSDAY THROUGH TUESDAY/
 
 
HIGHLIGHTS...  
 
* MAINLY DRY THU/FRI WITH SEASONABLE TEMPERATURES AND COMFORTABLE  
HUMIDITY  
 
* HOT WEATHER RETURNS LATE THIS WEEKEND INTO EARLY NEXT WEEK AND  
WHILE A FEW THUNDERSTORMS ARE POSSIBLE, DRY WEATHER SHOULD  
DOMINATE MOST OF THIS TIME  
 
DETAILS...  
 
THURSDAY AND FRIDAY...  
 
WITH CHRIS PASSING WELL SE OF THE 40N/70W BENCHMARK, AND MOVING  
FARTHER AWAY THURSDAY, ANY LINGERING SOUTH SWELL SHOULD  
DIMINISH. HIGH PRESSURE TO OUR NORTH WILL GRADUALLY OVERSPREAD  
OUR REGION, PROVIDING DRY WEATHER. EXPECTING NEAR NORMAL  
TEMPERATURES THROUGH THIS PERIOD. HUMIDITY INCREASES FRIDAY FROM  
THURSDAY, BUT STILL EXPECTED TO REMAIN RELATIVELY COMFORTABLE.  
 
THIS WEEKEND INTO EARLY NEXT WEEK...  
 
TRICKY PATTERN SHIFT DURING THIS TIME. A MID LEVEL TROUGH SHOULD  
LIFT OUT TO SOME EXTENT, WITH A DEEPER MID LEVEL TROUGH POISED  
TO ARRIVE TOWARDS THE MIDDLE OF NEXT WEEK. IT WILL ALL COME DOWN  
TO TIMING, WHICH REMAINS QUESTIONABLE DUE TO THE FAIRLY ZONAL  
FLOW. IN MOST CASES, EXPECTING TEMPERATURES TO START RISING THIS  
WEEKEND INTO EARLY NEXT WEEK, AT LEAST AWAY FROM ANY OCEAN  
INFLUENCE.  
 
HUMIDITY SHOULD SLOWLY INCREASE, TOO. WITH NO SYNOPTIC FEATURE  
TO REALLY FORCE THE ISSUE, ANY SHOWERS AND THUNDERSTORMS WOULD  
BE MORE OF THE AIRMASS VARIETY, DRIVEN ALMOST ENTIRELY BY  
DIURNAL HEATING. WHILE WE CANNOT ENTIRELY RULE OUT A FEW SHOWERS  
AND THUNDERSTORMS DURING THIS TIME, MUCH OF THIS PERIOD SHOULD  
REMAIN DRY FOR MOST LOCATIONS.  
 

 
   
AVIATION /20Z TUESDAY 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/...HIGH CONFIDENCE.  
 
TONIGHT... SCATTERED SHOWERS/T-STORMS MOVING SOUTH ACROSS SNE.  
MAINLY VFR, BUT BRIEF MVFR-IFR POSSIBLE IN SHOWERS/T-STORMS.  
WINDS SHIFTING TO NORTH. ACK MAY SEE A BRIEF PERIOD OF FOG  
BEFORE SUNRISE AS WINDS WEAKEN OUT OF THE SW AND INVERSION  
REMAINS ALOFT.  
 
WEDNESDAY...  
MAINLY VFR. A FEW MORNING SHOWERS MAY LINGER ACROSS SE NEW ENG  
IN EARLY MORNING.  
 
WEDNESDAY NIGHT...  
MAINLY VFR. STRONG WINDS OUT OF THE NE ACROSS SE NEW ENG.  
 
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. GREATEST RISK FOR A FEW  
THUNDERSTORMS AND/OR SHOWERS IN THE VICINITY OF THE TERMINAL  
AROUND 00Z.  
 
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.  
 
OUTLOOK /THURSDAY THROUGH SUNDAY/...  
 
THURSDAY THROUGH FRIDAY NIGHT: VFR.  
 
SATURDAY THROUGH SATURDAY NIGHT: VFR. SLIGHT CHANCE SHRA.  
 
SUNDAY: VFR. SLIGHT CHANCE SHRA, ISOLATED TSRA.  
 

 
   
MARINE
 
 
FORECASTER CONFIDENCE LEVELS...  
 
LOW - LESS THAN 30 PERCENT.  
MODERATE - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
SHORT TERM /THROUGH WEDNESDAY NIGHT/...HIGH CONFIDENCE.  
 
DIMINISHING WINDS TONIGHT WITH WIND SHIFT TO N BEHIND THE COLD  
FRONT. A FEW SHOWERS AND AN ISO STRONG T-STORM OR TWO WITH  
GUSTY WINDS POSSIBLE TONIGHT. NE WINDS 10-20 KT WED AFTERNOON  
ACROSS THE SE COASTS. WITH TS CHRIS OFF TO OUR SE, SEAS MAY  
BUILD UP TO 8 FT POSSIBLE OVER THE SOUTHERN WATERS. A HIGH SURF  
ADVISORY MAY BE NEEDED. WITH STRONG NE WINDS AND BUILDING  
SOUTHERLY SWELL, CHOPPY CONDITIONS ON THE WATERS IS POSSIBLE.  
 
OUTLOOK /THURSDAY THROUGH SUNDAY/...  
 
THURSDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING  
5 FT.  
 
THURSDAY NIGHT: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING  
5 FT.  
 
FRIDAY THROUGH FRIDAY NIGHT: WINDS LESS THAN 25 KT.  
 
SATURDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.  
 
SATURDAY NIGHT: WINDS LESS THAN 25 KT. AREAS OF SEAS  
APPROACHING 5 FT. SLIGHT CHANCE OF RAIN SHOWERS.  
 
SUNDAY: WINDS LESS THAN 25 KT.  
 

 
   
BOX WATCHES/WARNINGS/ADVISORIES
 
 
CT...NONE.  
MA...AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR MAZ013-  
016>023.  
RI...AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>008.  
MARINE...SMALL CRAFT ADVISORY FROM 11 AM TO 7 PM EDT WEDNESDAY FOR  
ANZ231>234.  
SMALL CRAFT ADVISORY FROM 11 AM WEDNESDAY TO 6 AM EDT THURSDAY  
FOR ANZ235-254>256.  
 

 
 

 
SYNOPSIS...BELK/CORREIA  
NEAR TERM...NOCERA/CORREIA  
SHORT TERM...NOCERA/CORREIA  
LONG TERM...BELK  
AVIATION...BELK/NOCERA/CORREIA  
MARINE...BELK/NOCERA/CORREIA  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MA Page
The Nexlab RI Page
The Nexlab NH Page
The Nexlab CT Page Main Text Page