Today: Hi 82 °F
Tonight: Lo 64 °F
Dew Point: 55.0°F
UV Index: 6.7
Barometer: 29.98 in S
Rain Rate: 0.00 in/hr
Rain Today: 0.00 in
Rain Thursday: 0.00 in
Visibility: 10 miles
Now: 1 mph
Avg: 1 mph
Gusts: 7 mph
National Weather Service Boston / Norton, MA
Point Forecast Updated Fri Jun 18, 2021 6:32am EDT
Warmer today with low humidity. A warm front may bring a few showers tonight into Saturday morning, then another round of showers and thunderstorms is possible Saturday afternoon/evening ahead of a cold front. Dry, very warm but less humid conditions follow on Sunday. Heat and increasing humidity returns early next week along with the risk of tropical downpours Monday night/Tuesday. Trending cooler, drier and less humid mid week.
Hi 82 °F
Sunny, with a high near 82. Southwest wind 5 to 9 mph.
Mostly Cloudy then Chance Rain Showers
Lo 64 °F
A chance of rain showers after 1am. Mostly cloudy, with a low around 64. Southwest wind around 10 mph. Chance of precipitation is 30%.
Chance Showers And T-Storms
Hi 84 °F
A chance of rain showers before 10am, then a chance of showers and thunderstorms between 10am and 4pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 84. Southwest wind around 9 mph. Chance of precipitation is 40%.
Chance Showers And T-Storms
Lo 64 °F
A chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 64. West wind around 8 mph. Chance of precipitation is 30%.
Hi 86 °F
Sunny, with a high near 86. West wind around 8 mph.
Lo 65 °F
Mostly clear, with a low around 65. Southwest wind 3 to 7 mph.
Mostly Sunny then Slight Chance Showers And T-Storms
Hi 92 °F
A slight chance of showers and thunderstorms after 5pm. Mostly sunny, with a high near 92. Southwest wind 3 to 13 mph.
Chance Showers And T-Storms
Lo 70 °F
A chance of showers and thunderstorms. Mostly cloudy, with a low around 70. South wind 6 to 13 mph. Chance of precipitation is 40%.
Chance Showers And T-Storms then Showers And T-Storms Likely
Hi 84 °F
A chance of showers and thunderstorms before 8am, then showers and thunderstorms likely. Partly sunny, with a high near 84. Southwest wind 6 to 10 mph, with gusts as high as 22 mph. Chance of precipitation is 60%.
Chance Rain Showers
Lo 61 °F
A chance of rain showers. Mostly cloudy, with a low around 61. West wind 6 to 9 mph. Chance of precipitation is 40%.
Slight Chance Rain Showers then Mostly Sunny
Hi 76 °F
A slight chance of rain showers before 8am. Mostly sunny, with a high near 76. West wind around 7 mph.
Lo 56 °F
Mostly clear, with a low around 56. West wind 3 to 7 mph.
Hi 79 °F
Sunny, with a high near 79. North wind 3 to 7 mph.
Lo 58 °F
Mostly clear, with a low around 58. Southwest wind 3 to 7 mph.
National Weather Service Boston / Norton, MA
Updated Fri Jun 18, 2021 10:30am EDT
000 FXUS61 KBOX 181422 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 1022 AM EDT Fri Jun 18 2021 .SYNOPSIS... Warmer today with low humidity. A warm front may bring a few showers tonight into Saturday morning, then another round of showers and thunderstorms is possible Saturday afternoon/evening ahead of a cold front. Dry, very warm but less humid conditions follow on Sunday. Heat and increasing humidity returns early next week along with the risk of tropical downpours Monday night/Tuesday. Trending cooler, drier and less humid mid week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1010 AM Update... High pressure centered off the Mid Atlantic coast will maintain dry weather for most of Southern New England today. Visible satellite shows mid and high clouds streaming into Upstate NY and Northern VT, out ahead of a MCS moving across southern WI and northwest OH. For us here in Southern New England, increasing southwest flow out ahead of the aforementioned shortwave will lead to somewhat breezy conditions and temperatures rising into the low to mid 80s, cooler on the coast as well as the Cape and Islands. A well-mixed boundary layer should minimize the development of sea breezes. Plentiful sunshine although clouds will be on the increase from the west by the afternoon hours. Overall, a very delightful and low humidity early summer day. Enjoy! Previous discussion... After a cool start temperatures will quickly warm up today.High pressure slides south and east of southern New England resulting in prevailing winds shifting to the southwest. This will result in higher dewpoints in the upper 40s to low 50s being advected into the region. Despite the higher dewpoints conditions will remain fairly dry with lowest RH this afternoon in the 30-40 percent range. High temperatures are expected to be slightly above normal for this time of year as 20C temps at 925 hPa will support temperatures in the low-mid 80sF at the surface. As deep- layer moisture is advected over the region from the south and west we'll also see increasing cloud cover by mid-late afternoon. However skies should be mostly clear for the majority of the day with the exception of some diurnal cu/stratocu. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... Highlights * Showers possible Tonight into Saturday * Isolated to scattered showers/thunderstorms Saturday. Tonight By Friday night moisture advection over southern New England will jack PWATs up close to 1.5". This falls just below the 90th percentile (1.55") compared to sounding climatology. With ample moisture in place and a weak-short wave at 500 hPa moving over head, we will have a chance for some scattered showers and possibly a rumble of thunder tonight into Saturday. Best chance for thunder will be out west where there is expected to be weak instability (100-250 J/Kg of MUCAPE). With overcast skies settling over the region Friday evening, temperatures will stay mild with lows falling into the low-mid 60s. Tomorrow and Tomorrow night SPC has placed a large portion of the Northeast (including southern New England) under a marginal risk for severe thunderstorms on Saturday afternoon. As scattered-showers from Friday night exit the region Saturday morning, a second more robust short-wave trough will approach New England from The Great Lakes region. Moisture (dewpoints in the mid 60s, PWATs ~1.5"), deep-layer shear (40+ knots), and instability (500+ J/kg MLCAPE) will all be available to support the development of thunderstorms that could become severe. The only ingredient missing is a source of lift, which in this instance will be the approaching short-wave and associated surface front. Latest guidance does not have these features arriving in southern New England until Saturday evening when the time of maximum instability will have passed. Thus, any widespread convective activity is not favorable at this point. This forecast is further supported by latest hi-res model guidance from the HREF which is hinting at shower/thunderstorm activity that would be more isolated to scattered in nature. Should the approaching short-wave arrive sooner we could be looking at a different outcome, so we'll be monitoring this feature closely over the next 24 hours. Should severe thunderstorms develop Saturday afternoon, damaging wind gusts would be the primary hazard. As the short- wave exits east overnight Saturday into Sunday morning, we'll see the atmosphere dry out a bit with clearing skies. Mild temperatures Sunday morning in the low mid-60s. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Big Picture... Weak upper ridge builds over the Northeast USA Sunday, cresting Monday. Tropical system along the Gulf Coast moves through the Southeast USA to the Southern New England coast by Tuesday. This draws large amounts of moisture up the coast in the form of rain. At the same time, a cold front sweeps east from the Great Lakes, crossing New England on Tuesday Great Plains high pressure then brings dry weather for Wednesday and Thursday. Mass fields are similar Sunday and Monday. Differences arise with the tropical system, with the GFS/Canadian/ECMWF showing different timing on the 500-mb shortwave and surface system...the GFS quite different with an inland surface system. There are also increasing differences between the models regarding a broad upper trough over Central Canada and the Great Lakes. Confidence is moderate-high Sunday and Monday, trending to moderate midweek. Details... Sunday and Monday... High pressure builds Sunday and moves overhead Monday morning. Dew points drop back a little on Sunday...mid 50s NW to mid 60s South Coast...then climb into the mid-upper 60s Monday afternoon as the high moves offshore and the flow turns from the south and southwest. Temps at the top of the mixed layer Sunday 16-17C which would support mid to upper 80s. Temps at the top of the layer Monday 17- 20C which supports 90-95 except cooler 80s along the south coast. Monday night and Tuesday... Warm and humid airmass in place, associated with the flow of air from the tropical weather system. Dew points remain in the mid to upper 60s during the period. PW values will be at least 1.5 inches and possibly up to 2 inches. Shortwave trough embedded in the upper trough to our west...this sweeps across New England Tuesday afternoon and evening. Surface cold front moves through with the shortwave. Convective parameters show buoyancy/instability with CAPE 1500-2500 J/Kg and Totals in the upper 40s. Lifted Index values minus 3 to minus 6 ahead of the shortwave and front. Based on this, expect showers and scattered thunder mainly during the afternoon and evening. The high moisture values suggest potential for downpours. Once the cold front moves through, conditions should improve with showers ending and dew points lowering into the 50s. Wednesday and Thursday... High pressure builds in with subsidence and dew points mid 40s to mid 50s. Temps aloft 8-11C support max temps in the 70s and low 80s. Comfortable each day with seasonable temperatures. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... Forecaster Confidence Levels. Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today...High confidence. VFR. Winds becoming more SW. Tonight...High confidence. VFR. VCSH moving in after 04Z. Gusty southwest winds 20+ knots kick in at The Cape and Island terminals after 00Z. Saturday...High confidence in large scale, but moderate confidence in timing. VFR with patches of MVFR in isolated heavier showers and thunderstorms in the afternoon. A few showers and thunderstorms, some with reduced visibility in heavier downpours. Southwest winds 10 to 15 kt. Saturday night...High confidence. Cold front moves through. Winds shift out of the west 10 kt. VFR. KBOS TAF...High Confidence in TAF. KBDL TAF...High Confidence in TAF. Outlook /Sunday through Tuesday/... Sunday through Sunday Night: VFR. Monday: Mainly VFR, with local MVFR possible. Breezy. Slight chance SHRA, isolated TSRA. Monday Night: Mainly MVFR, with local IFR possible. Breezy. Chance SHRA, slight chance TSRA. Tuesday: Mainly MVFR, with local IFR possible. Breezy. Chance SHRA, chance TSRA. && .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. Today High pressure slides south and east of the coastal waters today resulting in a wind shift to the southwest. Wind speeds pick up this afternoon to the 15-2 knot range. Seas from 0-3 feet. Tonight Southwest winds at 15 knots continue tonight with gusts greater than 20 knots. Seas increase to 3-5 feet for the outer marine zones which has prompted a small craft advisory beginning at 00Z and ending at 22Z Saturday. Saturday and Saturday night 5 foot seas continue for the outer waters south of The Islands Saturday afternoon. SCA set to expire at 22Z but may need to be extended should 5 foot seas linger. Weak cold frontal passage may produce isolated showers/thunderstorms over the coastal waters Saturday night into Sunday. Outlook /Sunday through Tuesday/... Sunday: Winds less than 25 kt. Seas up to 5 ft. Sunday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Monday: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers. Monday Night: Winds less than 25 kt. Seas up to 5 ft. Chance of rain showers, slight chance of thunderstorms. Tuesday: Winds less than 25 kt. Rough seas up to 9 ft. Chance of rain showers, chance of thunderstorms. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory from 10 AM to 6 PM EDT Saturday for ANZ254. Small Craft Advisory from 5 AM to 6 PM EDT Saturday for ANZ255. Small Craft Advisory from 11 PM this evening to 6 PM EDT Saturday for ANZ256. && $$ SYNOPSIS...WTB/RM NEAR TERM...WTB/Chai/RM SHORT TERM...RM LONG TERM...WTB AVIATION...WTB/RM MARINE...WTB/RM
Note: Rain measured automatically by weather station. Rain totals do not necessarily include melted frozen precipitation.
For more accurate, manually measured rain data, see the Local Precip Data page.
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No alerts/warnings active for Southeast Middlesex County.
Alerts active nearby in: Coastal Waters extending out to 25 nm South of Marthas Vineyard and Nantucket; Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 nm South of Block Island; Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 nm
15 hours 18 minutes
Waxing Gibbous (56%)