Monday, September 1, 2025
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
MONDAY, SEPTEMBER 1, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0510E
SUNSET: 1818E
CLOUDY SKIES AND COOLER TEMPS WELCOME THE FIRST DAY
OF METEOROLOGICAL FALL….
Today we have had mostly cloudy conditions with only a small
showing of the sun throughout the morning and early afternoon
hours. Most of the cloud coverage has been upper level cirrus
clouds with a few cumulus and altocumulus occasionally. The
wind was more active earlier in the morning and has slowed down
with a shift in direction as a sea-breeze took over the region.
Temperatures started off in the low 60’s today, with an overnight
low of 55F. The air mass is not as dry, as indicated by an
increase of dew point values, which has made it feel slightly
more sticky than the previous days. There was a slight breeze
from the east-northeast that has helped the air feel cooler, and
part of that is why temperatures are still below the normal value
of 78F. So far, we have only got to 73F.
The wind has been on the light side today, only averaging around
9mph. Wind flow started out of the north-northwest today and by
the afternoon, winds have switched to a more east-north easterly
flow. The peak gust for the day so far is 23mph, which occurred
just before 10am this morning.
Visibility was still holding well at 70 miles this morning, but
slowly decreased with the slight increase in dew point values.
We finished the early afternoon at around 60 miles.
The maximum temperature so far today is 73F degrees, which is
5 degrees below the normal high of 78F. The minimum temperature
since midnight is 55 degrees, which is 5 degrees below the normal
low of 60F.
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PRELIMINARY STATS FOR AUGUST 2025
TEMPERATURE, Deg. F
Avg. Max. 79.5 [-0.7]
Avg. Min. 59.3 [-3.3]
Mean 69.4 [-2.0]
24-hour corrected mean: 68.5
Max. for month: 94F on the 11th
Min. for month: 51F on the 20th
HEATING DEGREE DAYS
Total heating units: 19 [+008]
Total for the season: 20 [+002]
Total for last season: 11
COOLING DEGREE DAYS
Total cooling units: 161 [-048]
Total for the season: 672 [+076]
Total for last season: 694
PRECIPITATION, Inches
Total: 1.88 [-2.03]
Greatest in 24 hrs: 0.68 on the 14th
SNOWFALL, Inches
Total: 0.0 [ 0.0]
Greatest in 24 hrs: N/A
WIND, mph
Avg. uncorrected wind speed: 8.8 mph
Avg. corrected wind speed: 9.5 mph
Prevailing wind direction: South-southwest [15%]
Peak gust and direction: 41 NE on the 17th
SUNSHINE:
Campbell-Stokes card minutes: 18302 of a possible 22780, or 74%
Astronomical total minutes: 18979 of a possible 25724 or 74%
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Today’s Observations:
7 A.M.
Weather: Scattered cirrostratus, broken cirrus
Temperature: 61F; Dew Point: 54F; Relative Humidity: 78%
Wind: NNE @ 9 kts
Sea-level pressure: 1025.2 mb; 30.27 in. Hg: rising, then
more slowly
Visibility: 70 miles
6-hr Max temp: 61F
6-hr Min temp: 55F
24-hr Precip: 0.00 inches
BHO SA 1155 E220 SCT 250 BKN 70 252/61/54/0209/027/ 8/008
51010 10061 20055
10 A.M.
Weather: Broken cirrostratus, broken cirrus, few cumulus
ESE-SE, few altocumulus/castellanus ESE-SE
Temperature: 68F; Dew Point: 57F; Relative Humidity: 67%
Wind: ENE @ 10G17 kts
Sea-level pressure: 1026.1 mb; 30.30 in. Hg: rising unsteadily
Visibility: 60 miles
3-hr Precip: 0.00 inches
BHO SA 1455 E220 BKN 250 BKN 60 261/68/57/0710G17/030/
FEW CU DSNT ESE-SE FEW AC/ACC DSNT ESE-SE/ 8/288 52009
1 P.M.
Weather: Broken cirrostratus, broken cirrus, few cumulus
all quadrants
Temperature: 69F Dew Point: 61F; Relative Humidity: 77%
Wind: ENE @ 7 kts
Sea-level pressure: 1026.0 mb; 30.30 in. Hg: rising, then
falling
Visibility: 60 miles
6-hr Max temp: 73F
6-hr Min temp: 61F
6-hr Precip: 0.00 inches
BHO SA 1755 E220 BKN 250 BKN 60 260/69/61/0707/030/ FEW CU
ALQDS SUN DMLY VSBL/ 8/208 58001 10073 20061
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SUMMARY FOR SUNDAY, AUGUST 31, 2025
TEMPERATURE (DEGREES F)
MAX…….75 NORMAL…..78
MIN…….53 NORMAL…..60
MEAN……64 NORMAL…..69
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-5
TOTAL DEPARTURE FOR THE MONTH………………………-59 [-2.1 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY……………..1 DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH…………….19 DEPARTURE……..+8
TOTAL HEATING UNITS FOR THE SEASON……………20 DEPARTURE……..+2
TOTAL HEATING UNITS LAST SEASON TO DATE……….11 DEPARTURE……..+9
COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..0 DEPARTURE……..-5
TOTAL COOLING UNITS FOR THE MONTH……………161 DEPARTURE…….-43
TOTAL COOLING UNITS FOR THE SEASON…………..672 DEPARTURE…….+81
TOTAL COOLING UNITS LAST SEASON TO DATE………689 DEPARTURE…….-17
PEAK WIND GUST (MPH):
Note: Instruments designated #1 = Main Tower, #2 = South Tower,
F420C, Contacting, Merlin, and Richards are all on Main Tower.
E=Estimated
F420C (Official)………..17 N @ 10:55 A.M.
VECTOR #1 (1-Sec)……….18 NNW @ 08:05 A.M.
VECTOR #2 (1-Sec)……….18 NNW @ 10:54 A.M.
DAVIS #1……………….16 NW @ 02:42 A.M.
DAVIS #2 ………………17 N @ 08:09 A.M.
RMY #1 (Instantaneous)…..17 NNW @ 05:51 A.M.
RMY #2 (Instantaneous)…..18 NNW @ 08:09 A.M.
MERLIN…………………17 NNE
RICHARDS (C5C) (Inst)……16 NE @ 12:08 P.M.
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………13 NW @ 05:34 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..12 @ 02:45 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..13 @ 05:50 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………12 NW @ 05:52 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………12 NNW @ 05:50 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..12 NW @ 02:43 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..13 NW @ 05:50 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………12 NW @ 05:52 A.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.6 NW [183 total miles]
VECTOR #1……………….7.9
VECTOR #2……………….8.2
DAVIS #1………………..8.0 N
DAVIS #2………………..7.9 NNE
RMY #1………………….7.8 N
RMY #2………………….8.1 N
RICHARDS (C5C)…………..8.3
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.11
TOTAL PRECIPITATION FOR THE MONTH…………..1.88 DEPARTURE…..-2.03
TOTAL PRECIPITATION FOR THE YEAR (2025)…….31.33 DEPARTURE…..-3.28
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PRELIMINARY CLIMATE SUMMARY FOR AUGUST CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN)/SUN(%)/PEAK GUST/VEC1/RMY GUST
PEAK GUST: F420C (Official)
VEC1: Vector #1 1-second gust
RMY: R.M. Young #1 wind gust recording system (Instantaneous)
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M: Missing data
8/1 71/57/64/-9/0.44/546/63 28 NE VEC1 28 NE RMY 27
8/2 75/54/65/-8/0.00/838/97 18 NNW VEC1 18 NNW RMY 18
8/3 83/59/71/-2/0.00/784/91 21 SSW VEC1 21 SSW RMY 21
8/4 84/61/73/0/0.00/757/88 17 W VEC1 17 W RMY 17
8/5 73/62/68/-5/0.00/480/56 28 NE VEC1 27 NE RMY 28
8/6 77/61/69/-4/0.00/248/29 17 ENE VEC1 17 ENE RMY 16
8/7 81/61/71/-2/0.00/665/78 18 ESE VEC1 18 ESE RMY 17
8/8 83/61/72/0/0.00/834/98 21 SSW VEC1 21 SSW RMY 21
8/9 83/60/72/0/0.00/814/96 22 S VEC1 22 SSW RMY 22
8/10 89/61/75/+3/0.00/761/90 22 S VEC1 22 S RMY 21
8/11 94/67/81/+9/0.00/792/94 20 W VEC1 19 W RMY 19
8/12 93/68/81/+9/0.00/806/96 21 SSW VEC1 21 SSW RMY 21
8/13 88/66/77/+5/0.00/344/41 25 SW VEC1 25 SW RMY 25
8/14 90/68/79/+7/0.68/426/51 35 NE VEC1 34 NE RMY 36 TSTM
8/15 75/63/69/-3/0.00/783/96 29 NE VEC1 29 ENE RMY 31
8/16 86/62/74/+2/0.00/730/88 23 S VEC1 24 S RMY 23
8/17 89/64/77/+5/0.19/414/50 41 NE VEC1 43 NE RMY 42 TSTM
8/18 68/55/62/-9/0.00/627/76 32 NE VEC1 34 NE RMY 34
8/19 73/54/64/-7/0.00/560/68 20 SE VEC1 19 SE RMY 18
8/20 63/51/57-14/0.51/008/01 22 ENE VEC1 22 ENE RMY 21
8/21 67/54/61/-10/T/303/37 36 ENE VEC1 35 NE RMY 36
8/22 79/53/66/-5/0.00/774/95 24 N VEC1 25 N RMY 25
8/23 85/60/73/+2/0.00/771/95 33 SSW VEC1 33 SSW RMY 35
8/24 80/60/70/-1/0.00/632/78 33 SSW VEC1 35 SSW RMY 34
8/25 83/63/73/+3/T/533/66 23 WSW VEC1 22 SW RMY 23
8/26 77/59/68/-2/0.00/765/95 28 WNW VEC1 27 WNW RMY 28
8/27 75/57/66/-4/T/634/79 26 WNW VEC1 26 NW RMY 27
8/28 77/52/65/-5/T/711/89 31 SSW VEC1 31 SSW RMY 31
8/29 73/59/66/-4/0.06/191/24 29 SSE VEC1 29 SSE RMY 29
8/30 75/52/64/-5/0.00/658/83 21 W VEC1 21 W RMY 22
8/31 75/53/64/-5/0.00/790/100 17 N VEC1 18 NNW RMY 17
9/1 The low since midnight is 55F, the daily normal low is 60F.
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AUGUST DAILY RECORDS TO DATE
NONE.
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DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR SEPTEMBER 1
HIGH 93F IN 1969, 2010
LOW 47F IN 1975, 2017
PRECIP 2.32 INCHES IN 2013
PEAK GUST 59e MPH S IN 1945, SSW IN 1965
RECORDS FOR SEPTEMBER 2
HIGH 99F IN 1953 (SEPTEMBER MAXIMUM RECORD)
LOW 44F IN 1909
PRECIP 2.73 INCHES IN 1947
PEAK GUST 55e MPH WNW IN 1944
TODAY’S REPORT PREPARED BY: Amanda Joly/Matt Douglas
