595
FNUS71 KBOX 230603
FWSBOX
SPOT FORECAST FOR BIRCH HILL DAM RX FIRE 9/22/2026...MASSWILDLIFE
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
203 AM EDT WED SEP 23 2026
FORECAST IS BASED ON IGNITION TIME OF 0600 EDT ON SEPTEMBER 23.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL
WEATHER SERVICE.
DISCUSSION
DRY WEATHER WILL PERSIST THROUGH THURSDAY WITH GUSTY NE WINDS DURING
THE DAYLIGHT HOURS. WINDS WILL GUST TO BETWEEN 20 AND 25 MPH AT
TIMES.
TODAY
SKY/WEATHER.........MOSTLY SUNNY.
CWR.................0 PERCENT.
MAX TEMPERATURE.....AROUND 63.
MIN HUMIDITY........59 PERCENT.
DEWPOINT............41 INCREASING TO 46 IN THE LATE MORNING AND
AFTERNOON.
MIN APPARENT TEMP...37.
SURFACE WINDS (MPH).NORTHEAST WINDS 7 TO 13 MPH.
WIND (20 FT)........NORTHEAST WINDS 7 TO 13 MPH.
MIXING HEIGHT.......4700 FT AGL.
TRANSPORT WINDS.....NORTHEAST 12 TO 20 MPH SHIFTING TO THE EAST 20
TO 24 MPH IN THE LATE MORNING AND AFTERNOON.
SMOKE DISPERSAL.....POOR (4400 KNOT-FT) EARLY IN THE MORNING
INCREASING TO EXCELLENT (90800 KNOT-FT) IN THE
AFTERNOON.
LVORI...............3.
ADI.................8 EARLY IN THE MORNING INCREASING TO 68 IN THE
AFTERNOON.
CEILING (KFT).......24.
TIME (EDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........51 41 30 17 11 15 15 10 8 14 9 4
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............42 42 45 51 54 57 58 60 61 60 59 59
DEWPOINT........40 40 43 46 47 47 47 47 47 47 46 46
RH..............93 93 93 83 77 69 67 62 59 62 62 62
HEAT INDEX (F)..38 37 41 51 54 57 58 60 61 60 59 59
20 FT WIND DIR..NE NE NE NE NE NE E E E E E E
20 FT WIND SPD..7 8 7 9 10 12 13 13 12 12 10 9
20 FT WIND GUST.16 17 17 18 20 22 23 23 22 22 20 18
SURFACE WND DIR.NE NE NE NE NE NE E E E E E E
SURFACE WND SPD.7 8 7 9 10 12 13 13 12 12 10 9
SURFACE WND GST.16 17 17 18 20 22 23 23 22 22 20 18
MIX HGT (KFT)...0.5 0.4 1.0 2.0 3.0 3.9 4.3 4.5 4.7 4.6 4.2 3.7
TRANSP WIND DIR.NE NE NE E E E E E E E E E
TRANSP WIND SPD.12 12 13 20 22 24 23 23 22 22 21 20
LVORI...........5 5 5 3 3 1 1 1 1 1 1 1
ADI.............8 12 17 38 52 66 66 68 65 65 59 52
VRATE KT-FT/1K..5 4 11 34 57 81 86 91 90 88 76 63
VENTRATE CAT....PR PR PR PR FR GD GD GD GD GD GD GD
CEILING (KFT)...25 25 25 25 25 25 24 24 24 25 25 25
TONIGHT
SKY/WEATHER.........CLEAR.
CWR.................0 PERCENT.
MIN TEMPERATURE.....AROUND 40.
MAX HUMIDITY........100 PERCENT.
DEWPOINT............44 DECREASING TO 41 EARLY IN THE MORNING.
MIN APPARENT TEMP...37.
SURFACE WINDS (MPH).EAST WINDS 6 TO 8 MPH EARLY IN THE EVENING
BECOMING LIGHT, THEN BECOMING NORTHEAST 5 TO 6
MPH EARLY IN THE MORNING.
WIND (20 FT)........NORTHEAST WINDS 5 TO 6 MPH EARLY IN THE EVENING
BECOMING LIGHT, THEN BECOMING NORTHEAST 5 TO 6
MPH EARLY IN THE MORNING.
MIXING HEIGHT.......400 FT AGL.
TRANSPORT WINDS.....NORTHEAST 9 TO 15 MPH.
SMOKE DISPERSAL.....FAIR (20700 KNOT-FT) EARLY IN THE EVENING
DECREASING TO POOR (3400 KNOT-FT) LATE IN THE
NIGHT.
LVORI...............6.
ADI.................4 TO 31.
CEILING (KFT).......25.
TIME (EDT) 6 PM 8 PM 10 PM MIDNGT 2 AM 4 AM
SKY (%).........0 2 5 2 0 8
WEATHER COV.....
WEATHER TYPE....NONE NONE NONE NONE NONE NONE
TSTM COV........
CWR.............0 0 0 0 0 0
TEMP............55 48 45 44 42 42
DEWPOINT........46 44 44 43 42 42
RH..............72 86 96 96 100 100
HEAT INDEX (F)..55 47 44 42 41 39
20 FT WIND......E 8 E 3 NE 3 NE 3 NE 3 NE 5
20 FT WIND GUST.15 9 8 8 10 13
SURFACE WIND....E 8 E 3 NE 3 NE 3 NE 3 NE 5
SURFACE WND GST.15 9 8 8 10 13
MIX HGT (FT)....1600 400 400 400 400 400
TRANSPORT WIND..E 15 E 10 E 10 NE 10 NE 10 NE 12
LVORI...........3 6 8 8 9 9
ADI.............31 5 5 5 5 5
VRATE KT-FT/1K..21 4 4 4 4 4
VENTRATE CAT....POOR POOR POOR POOR POOR POOR
CEILING (KFT)...25 25 25 25 25 25
THURSDAY
SKY/WEATHER.........SUNNY.
CWR.................0 PERCENT.
MAX TEMPERATURE.....AROUND 64.
MIN HUMIDITY........54 PERCENT.
DEWPOINT............42 INCREASING TO 45 IN THE AFTERNOON.
MIN APPARENT TEMP...36.
SURFACE WINDS (MPH).NORTHEAST WINDS 6 TO 10 MPH.
WIND (20 FT)........NORTHEAST WINDS 6 TO 10 MPH.
MIXING HEIGHT.......4100 FT AGL.
TRANSPORT WINDS.....NORTHEAST 12 TO 21 MPH.
SMOKE DISPERSAL.....POOR (4300 KNOT-FT) EARLY IN THE MORNING
INCREASING TO EXCELLENT (63700 KNOT-FT) IN THE
AFTERNOON.
LVORI...............5.
ADI.................5 EARLY IN THE MORNING INCREASING TO 62 IN THE
AFTERNOON.
CEILING (KFT).......25.
TIME (EDT) 6 AM 8 AM 10 AM NOON 2 PM 4 PM
SKY (%).........5 1 5 4 15 18
WEATHER COV.....
WEATHER TYPE....NONE NONE NONE NONE NONE NONE
TSTM COV........
CWR.............0 0 0 0 0 0
TEMP............41 44 54 58 62 62
DEWPOINT........41 42 44 44 45 46
RH..............100 92 69 60 54 55
HEAT INDEX (F)..37 41 54 58 62 62
20 FT WIND......NE 6 NE 6 NE 10 NE 10 NE 10 NE 9
20 FT WIND GUST.14 15 20 20 18 17
SURFACE WIND....NE 6 NE 6 NE 10 NE 10 NE 10 NE 9
SURFACE WND GST.14 15 20 20 18 17
MIX HGT (FT)....400 900 2700 3500 4000 3700
TRANSPORT WIND..NE 12 NE 13 NE 20 E 20 E 18 E 16
LVORI...........9 5 1 1 1 1
ADI.............5 15 45 51 51 43
VRATE KT-FT/1K..4 10 47 59 64 52
VENTRATE CAT....POOR POOR FAIR FAIR GOOD FAIR
CEILING (KFT)...25 25 25 25 25 25
FORECASTER...BRW
REQUESTED BY...ALEX ENTRUP
TYPE OF REQUEST...PRESCRIBED
.TAG 2622380.0/BOX
.DELDT 09/23/26
.FORMATTERVERSION 2.0.0
.EMAIL ALEX.ENTRUP@MASS.GOV
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