Spot Forecast
Issued by NWS Boston, MA
Issued by NWS Boston, MA
Versions:
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FNUS71 KBOX 081354
FWSBOX
Spot Forecast for Onset Festival...MASS Dept of Fire Services
National Weather Service Boston/Norton MA
954 AM EDT Sat Aug 8 2026
Forecast is based on forecast start time of 1000 EDT on August 08.
If conditions become unrepresentative, contact the National
Weather Service.
.DISCUSSION...
Very warm and sunny for much of the day in and around Onset, MA,
with high temperatures reaching the upper 80s and maximum apparent
temperatures in the upper 90s this afternoon.
Late this afternoon into early Saturday evening, pop-up
thunderstorms are expected to develop across western Massachusetts
and could approach the Onset area between 7 PM and 10 PM.
However, confidence in the overall coverage of storms is lower due
to their hit-or-miss nature.
That said, any storm that develops could produce lightning, gusty
winds, and heavy downpours. The threat for thunderstorms should
come to an end by around midnight.
.REST OF TODAY...
Sky/weather.........Sunny.
Chance of pcpn......0 percent.
Chance of pcpn......0 percent.
Chance of pcpn......0 percent.
Chance of rain......4 percent.
Chance of thunder...6 percent.
Begin/end of pcpn...
Max temperature.....77-88.
Min humidity........63-85 percent.
Max apparent temp...97.
Max apparent temp...97.
Max apparent temp...97.
Eye level winds.....Southwest winds up to 14 mph.
Surface winds (mph).Southwest winds 7 to 23 mph.
Wind (20 ft)........Southwest winds 7 to 23 mph.
Wave height.........2 feet building to 4 feet in the afternoon.
Rainfall amount.....0.00 inches.
Pcpn amount.........0.00 inches.
Snowfall amount.....0.0 inches.
CEILING (KFT).......15 increasing to 20 early.
Visibility..........9.
Water temperature...
Mixing height.......600 ft AGL.
Transport winds.....Southwest 13 to 18 mph.
Smoke dispersal.....Poor (3300 knot-ft) early in the morning
increasing to excellent (70800 knot-ft) in the
afternoon.
LVORI...............5.
ADI.................45 early in the morning increasing to 96 in the
afternoon.
TIME (EDT) 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........13 11 11 13 18 35 25 19
Weather cov.....
Weather type....
Tstm cov........
Chc of pcpn (%).0 0 0 0 0 0 0 0
Chc of rain (%).0 0 0 0 0 0 0 0
Chc of thdr (%).0 0 0 10 10 10 10 10
Temp............78 80 81 82 83 82 82 81
RH..............87 83 80 77 75 75 75 76
Heat index (F)..86 90 94 95 97 96 96 94
Wind chill (F)..86 90 94 95 97 96 96 94
Aparnt tmp (F)..86 90 94 95 97 96 96 94
20 FT wind dir..W SW SW SW SW SW SW SW
20 FT wind spd..16 16 18 21 22 23 22 22
20 FT wind gust.22 22 24 25 26 29 28 29
Eye lvl wnd dir.W SW SW SW SW SW SW SW
Eye lvl wnd spd.10 10 11 13 13 14 13 13
Eye lvl wnd gst.13 13 14 15 16 17 17 17
Surface wnd dir.W SW SW SW SW SW SW SW
Surface wnd spd.16 16 18 21 22 23 22 22
Surface wnd gst.22 22 24 25 26 29 28 29
Mix hgt (kft)...0.6 0.6 0.6 0.6 0.5 0.5 0.5 0.5
Transp wind dir.W SW SW SW SW SW SW SW
Transp wind spd.13 15 15 16 17 18 18 18
LVORI...........6 5 5 5 4 4 4 4
ADI.............45 64 71 84 93 96 91 76
Vrate kt-ft/1K..31 46 51 61 68 71 66 55
Ventrate Cat....PR FR FR GD GD GD GD FR
Wave height (ft)2 2 3 3 4 4 4 4
Ceiling (kft)...15 20 20 20 20 20 20 20
Visibility (sm).9 9 9 9 9 9 9 9
Water temp......
.TONIGHT...
Sky/weather.........Partly cloudy then becoming mostly cloudy then
becoming partly cloudy. Chance of showers late
in the evening. Patchy fog after midnight.
Patchy fog early in the morning.
Chance of pcpn......50 percent.
Chance of pcpn......50 percent.
Chance of pcpn......50 percent.
Chance of rain......15 percent.
Chance of thunder...13 percent.
Begin/end of pcpn...
Min temperature.....Around 73.
Max humidity........90-97 percent.
Max apparent temp...92.
Max apparent temp...92.
Max apparent temp...92.
Eye level winds.....Southwest winds up to 13 mph.
Surface winds (mph).Southwest winds 5 to 22 mph.
Wind (20 ft)........Southwest winds 5 to 22 mph.
Wave height.........4 feet subsiding to 2 feet in the late evening
and overnight.
Rainfall amount.....0.03 inches.
Pcpn amount.........0.03 inches.
Snowfall amount.....0.0 inches.
CEILING (KFT).......13 decreasing to 10 late in the evening, then
decreasing to 9.0 decreasing to 5.0 increasing
to 7.0 increasing to 9.0 increasing to 15
decreasing to 11 early in the morning
decreasing to 7.0 decreasing to 3.5 early in
the morning.
Visibility..........9 decreasing to 1.00.
Water temperature...
Mixing height.......400 ft AGL.
Transport winds.....West 10 to 17 mph.
Smoke dispersal.....Good (40000 knot-ft) early in the evening
decreasing to poor (3400 knot-ft) late in the
night.
LVORI...............5.
ADI.................58 early in the evening decreasing to 12 late
in the night.
TIME (EDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........32 40 50 82 88 75 30 22 36 32 30 21
Weather cov..... CHC CHC PTY PTY PTY PTY PTY
Weather type.... RW RW FOG FOG FOG FOG FOG
Tstm cov........
Chc of pcpn (%).0 0 0 30 50 10 0 0 0 0 0 0
Chc of rain (%).0 10 20 20 10 0 10 10 20 20 20 20
Chc of thdr (%).10 10 10 10 10 10 10 0 0 0 0 0
Temp............80 79 78 76 76 75 75 75 74 74 74 73
RH..............78 81 83 85 87 88 87 88 88 89 90 90
Heat index (F)..92 88 84 77 77 77 77 77 76 76 76 76
Wind chill (F)..92 88 84 77 77 77 77 77 76 76 76 76
Aparnt tmp (F)..92 88 84 77 77 77 77 77 76 76 76 76
20 FT wind dir..SW SW SW SW SW SW SW SW SW SW SW SW
20 FT wind spd..22 20 20 18 18 17 16 15 15 14 14 14
20 FT wind gust.28 25 24 22 21 20 20 17 17 17 16 16
Eye lvl wnd dir.SW SW SW SW SW SW SW SW SW SW SW SW
Eye lvl wnd spd.13 12 12 11 11 10 10 9 9 8 8 8
Eye lvl wnd gst.17 15 14 13 13 12 12 10 10 10 10 10
Surface wnd dir.SW SW SW SW SW SW SW SW SW SW SW SW
Surface wnd spd.22 20 20 18 18 17 16 15 15 14 14 14
Surface wnd gst.28 25 24 22 21 20 20 17 17 17 16 16
Mix hgt (kft)...0.5 0.5 0.5 0.5 0.4 0.5 0.4 0.4 0.4 0.4 0.4 0.4
Transp wind dir.SW SW SW W W W W W W W W W
Transp wind spd.17 16 16 15 13 13 13 13 12 12 12 10
LVORI...........4 6 5 5 5 6 6 6 6 6 6 6
ADI.............58 28 21 21 16 16 15 16 15 14 13 12
Vrate kt-ft/1K..40 19 17 19 13 12 11 13 12 11 10 9
Ventrate Cat....FR PR PR PR PR PR PR PR PR PR PR PR
Wave height (ft)4 3 3 2 2 2 2 2 2 2 2 2
Ceiling (kft)...15 14 13 10 9.0 5.0 7.0 9.0 15 11 7.0 3.5
Visibility (sm).9 9 9 6 6 6 4 2.6 1.8 1.7 2.0 1.0
Water temp......
$$
Forecaster...Dooley
Requested by...I.C.
Type of request...OTHER
.TAG 2619219.0/BOX
.DELDT 08/08/26
.FormatterVersion 2.0.0
.EMAIL dfsisu1@gmail.com