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Spot Forecast for Herman Covey WMA Prescribed Fire...MassWildlife
National Weather Service Boston/Norton MA
831 AM EDT Tue May 12 2026

Forecast is based on ignition time of 1300 EDT on May 12.
If conditions become unrepresentative, contact the National
Weather Service.

.DISCUSSION...
High pressure will continue to be in control near the Herman Covey
WMA area today. Expect dry and quiet weather to prevail with
mostly clear skies and northwest winds around 10 mph. Mixing is
expected to be excellent this afternoon, with relative humidities
dropping into the mid 20s percent range. Thus expect smoke from
the fire to be transported towards the southeast, although
transport winds are on the weak side.

.REST OF TODAY...

Sky/weather.........Sunny.
CWR.................0 percent.
Max temperature.....Around 62.
Min humidity........26 percent.
Dewpoint............27.
Max apparent temp...62.
Surface winds (mph).Northwest winds around 9 mph.
Wind (20 ft)........Northwest winds around 9 mph.
Mixing height.......7800 ft AGL.
Transport winds.....Northwest 14 to 17 mph.
Smoke dispersal.....Excellent (84500 knot-ft).
LVORI...............1.
ADI.................104 to 105.
CEILING (KFT).......6.0.

TIME (EDT)      1PM 2PM 3PM 4PM 5PM
Sky (%).........20  26  22  17  13
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0
Temp............58  59  61  62  62
Dewpoint........27  27  27  27  27
RH..............30  29  27  26  26
Heat index (F)..58  59  61  62  62
20 FT wind dir..NW  NW  NW  NW  NW
20 FT wind spd..9   9   9   9   9
20 FT wind gust.15  16  15  15  14
Surface wnd dir.NW  NW  NW  NW  NW
Surface wnd spd.9   9   9   9   9
Surface wnd gst.15  16  15  15  14
Mix hgt (kft)...7.5 7.8 7.5 7.3 7.0
Transp wind dir.NW  NW  NW  NW  NW
Transp wind spd.14  15  17  15  14
LVORI...........1   1   1   1   1
ADI.............105 105 105 105 104
Vrate kt-ft/1K..90  101 113 95  85
Ventrate Cat....GD  VGD VGD GD  GD
Ceiling (kft)...6.0 6.0 6.0 6.0 6.0

.TONIGHT...

Sky/weather.........Partly cloudy then becoming mostly cloudy.
CWR.................0 percent.
Min temperature.....Around 42.
Max humidity........79 percent.
Dewpoint............31 increasing to 35 around midnight.
Min apparent temp...39.
Surface winds (mph).West winds 5 to 7 mph early in the evening
                    becoming light, then becoming south around 5
                    mph early in the morning.
Wind (20 ft)........West winds 5 to 7 mph early in the evening
                    becoming light, then becoming south around 5
                    mph early in the morning.
Mixing height.......100 ft AGL.
Transport winds.....Northwest 6 to 12 mph shifting to the south 5
                    to 7 mph around midnight.
Smoke dispersal.....Good (47900 knot-ft) early in the evening
                    decreasing to poor (500 knot-ft) late in the
                    night.
LVORI...............3.
ADI.................64 early in the evening decreasing to 2 late in
                    the night.
CEILING (KFT).......6.0 increasing to 12 late in the evening, then
                    increasing to 20 increasing to 25 decreasing to
                    20 decreasing to 13 early in the morning
                    decreasing to 12.

TIME (EDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........11  10  8   20  25  30  49  59  84  79  66  89
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   0   0   0   0
Temp............60  57  54  51  48  47  46  45  44  43  42  42
Dewpoint........29  31  33  33  33  34  34  34  35  35  35  36
RH..............31  37  45  50  56  60  63  65  70  73  76  79
Heat index (F)..60  57  54  51  48  47  46  45  44  41  40  39
20 FT wind dir..NW  W   W   W   SW  SW  S   S   S   S   S   S
20 FT wind spd..7   5   3   3   2   2   2   2   2   3   3   5
20 FT wind gust.12  9   6   6   5   3   3   5   5   6   7   8
Surface wnd dir.NW  W   W   W   SW  SW  S   S   S   S   S   S
Surface wnd spd.7   5   3   3   2   2   2   2   2   3   3   5
Surface wnd gst.12  9   6   6   5   3   3   5   5   6   7   8
Mix hgt (kft)...4.8 2.5 0.3 0.2 0.2 0.1 0.1 0.2 0.2 0.2 0.2 0.2
Transp wind dir.NW  NW  W   W   NW  S   S   S   S   S   S   S
Transp wind spd.12  8   6   7   6   5   5   6   7   6   6   7
LVORI...........1   2   2   2   3   3   3   3   3   3   4   4
ADI.............64  26  3   3   3   2   2   3   3   3   3   5
Vrate kt-ft/1K..48  18  1   1   1   1   1   1   1   1   1   2
Ventrate Cat....FR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR
Ceiling (kft)...6.0 6.0 6.0 12  20  25  20  20  15  14  13  12

.WEDNESDAY...

Sky/weather.........Cloudy. Chance of rain showers through the day.
CWR.................0 percent increasing to 22 percent late in the
                    afternoon.
Max temperature.....Around 61.
Min humidity........60 percent.
Dewpoint............38 increasing to 43 in the late morning and
                    afternoon.
Max apparent temp...59.
Surface winds (mph).South winds 5 to 14 mph increasing to 15 to 16
                    mph with gusts to around 28 mph late in the
                    afternoon.
Wind (20 ft)........South winds 6 to 16 mph with gusts to around 28
                    mph.
Mixing height.......5200 ft AGL.
Transport winds.....South 7 to 14 mph increasing to 20 to 29 mph.
Smoke dispersal.....Poor (2300 knot-ft) early in the morning
                    increasing to excellent (65000 knot-ft) in the
                    afternoon increasing to good (42400 knot-ft)
                    early in the morning increasing to excellent
                    (130100 knot-ft) in the afternoon late in the
                    afternoon.
LVORI...............3.
ADI.................7 early in the morning increasing to 90 in the
                    afternoon.
CEILING (KFT).......10 decreasing to 3.5.

TIME (EDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........88  91  95  91  90  92  91  92  91  97  91  84
Weather cov.....SCH CHC CHC CHC CHC CHC CHC SCH         SCH SCH
Weather type....RW  RW  RW  RW  RW  RW  RW  RW          RW  RW
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   20  20  20  20
Temp............44  46  48  50  52  53  54  55  56  57  58  59
Dewpoint........37  38  40  42  43  43  43  44  44  44  45  45
RH..............76  73  74  74  71  69  66  66  64  62  62  60
Heat index (F)..41  43  45  47  52  53  54  55  56  57  58  59
20 FT wind dir..S   S   S   S   S   S   S   S   S   S   S   S
20 FT wind spd..5   6   6   8   9   10  13  14  15  16  16  16
20 FT wind gust.9   10  12  15  18  21  23  24  25  26  28  28
Surface wnd dir.S   S   S   S   S   S   S   S   S   S   S   S
Surface wnd spd.5   6   6   8   9   10  13  14  15  16  16  16
Surface wnd gst.9   10  12  15  18  21  23  24  25  26  28  28
Mix hgt (kft)...0.4 0.5 0.7 1.6 1.9 2.2 3.6 3.5 2.9 5.2 3.8 2.5
Transp wind dir.S   S   S   S   S   S   S   S   S   S   S   S
Transp wind spd.7   7   10  13  14  17  21  21  23  29  24  20
LVORI...........4   3   3   3   3   1   1   1   1   1   1   1
ADI.............7   7   8   26  33  45  54  54  54  90  66  42
Vrate kt-ft/1K..2   3   6   18  23  33  65  63  59  130 81  42
Ventrate Cat....PR  PR  PR  PR  PR  PR  GD  GD  FR  VGD GD  FR
Ceiling (kft)...10  8.0 6.0 5.0 4.5 4.0 4.0 4.0 4.0 4.0 3.5 3.5

$$
Forecaster...Loconto
Requested by...Ben Mazzei
Type of request...PRESCRIBED
.TAG 2613372.2/BOX
.DELDT 05/12/26
.FormatterVersion 2.0.0
.EMAIL ben.mazzei@mass.gov