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Thursday, October 9, 2025

October 9, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA THURSDAY OCTOBER 9, 2025 ALL TIMES ARE…

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BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

THURSDAY OCTOBER 9, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0550E
SUNSET:  1711E

BRISK AND CHILLY TODAY WITH PLENTY OF SUNSHINE….

The summer-like weather is a thing of the past as full fledged
fall has taken over. Skies are brilliantly clear today allowing
for a ton of sunshine, but with continued cold air advection
taking place, temperatures are having a hard time rising today.
Another benefit of this polar air mass is the clarity of the
air, which is allowing for excellent visibility today.

Temperatures started the day in the low 40s this morning and
have only recovered to the mid 50s by early this afternoon.
This is nearly 10 degrees below the expected high for today!
The biggest difference are the dew point values, which have
dropped below the freezing mark for the first time this season.
The air is quite dry and there is definitely a sharp chill to
the air today.

Winds have been busy again today out of the north-northwest.
The average speed for the day so far is around 13mph. Gusts
have frequently been exceeding 20mph today, with a peak of
33mph occurring just before 8am this morning.

Visibility has been excellent today with a view of 80 miles!

The maximum temperature so far today is 55F degrees, which is
9 degrees below the normal high of 64F. The minimum temperature
since midnight is 41F degrees, which is 6 degrees below the
normal low of 47F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus distant NE-SSW and distant WSW
Temperature: 44F; Dew Point: 31F; Relative Humidity: 58%
Wind: NNW @ 12G22 kts
Sea-level pressure: 1029.3 mb; 30.40 in. Hg: rising, then more slowly
Visibility: 80 miles
6-hr Max temp: 47F
6-hr Min temp: 41F
24-hr Precip: 0.80 inches
BHO SA 1155 CLR 80 293/44/31/3412G22/040/ FEW SC DSNT NE-SSW
AND DSNT WSW/ 8/500 51031 70080 10047 20041

10 A.M.
Weather: Clear, few stratocumulus distant WNW-NE-SSE
Temperature: 49F; Dew Point: 31F; Relative Humidity: 48%
Wind: N @ 14G23 kts
Sea-level pressure: 1031.1 mb; 30.45 in. Hg: rising, then more slowly
Visibility: 80 miles
3-hr Precip: 0.00 inches
BHO SA 1455 CLR 80 311/49/31/3614G23/045/ FEW SC DSNT WNW-NE-SSE/
8/500 51018

1 P.M.
Weather: Clear, few stratocumulus distant WNW-NE-SSE, few cirrus
distant SE-S
Temperature: 53F Dew Point: 31F; Relative Humidity: 42%
Wind: NNW @ 10G21 kts
Sea-level pressure: 1030.7 mb; 30.44 in. Hg: rising, then falling
Visibility: 80 miles
6-hr Max temp: 55F
6-hr Min temp: 44F
6-hr Precip: 0.00 inches
BHO SA 1755 CLR 80 307/53/31/3410G21/044/ FEW SC DSNT WNW-NE-SSE
FEW CI DSNT SE-SSE/ 8/501 58004 10055 20044

————————————————————–

SUMMARY FOR WEDNESDAY, OCTOBER 8, 2025

TEMPERATURE (DEGREES F)
MAX…….68   NORMAL…..64
MIN…….49   NORMAL…..47
MEAN……59   NORMAL…..55

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….+4
TOTAL DEPARTURE FOR THE MONTH………………………+51 [+6.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY……………..6  DEPARTURE……..-4
TOTAL HEATING UNITS FOR THE MONTH…………….35  DEPARTURE…….-35
TOTAL HEATING UNITS FOR THE SEASON……………98  DEPARTURE…….-89
TOTAL HEATING UNITS LAST SEASON TO DATE………115  DEPARTURE…….-17

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE………0
TOTAL COOLING UNITS FOR THE MONTH…………….20  DEPARTURE…….+16
TOTAL COOLING UNITS FOR THE SEASON…………..756  DEPARTURE…….+82
TOTAL COOLING UNITS LAST SEASON TO DATE………757  DEPARTURE……..-1

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 *=Last of multiple occurrences

F420C (Official)………..33 NW   @   08:11 A.M.
VECTOR #1 (1-Sec)……….34 SSW  @   12:42 A.M.
VECTOR #2 (1-Sec)……….35 SW   @   01:19 A.M.
DAVIS #1……………….33 S    @   12:51 A.M.
DAVIS #2 ………………32 SSW  @   12:45 A.M.
RMY #1 (Instantaneous)…..35 SSW  @   12:10 A.M.
RMY #2 (Instantaneous)…..36 SSW  @   01:19 A.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)……32 SSW  @   02:35 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………23 SSW  @   03:01 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..23 SW   @   01:20 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..24 SSW  @   12:47 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………22 S    @   12:07 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………24 SSW  @   02:36 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..23 SW   @   01:20 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..25 SSW  @   12:48 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………21 SSW  @   12:30 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..14.4 NNW [345 total miles] VECTOR #1………………14.1
VECTOR #2………………14.5
DAVIS #1……………….14.1 WNW
DAVIS #2……………….14.3 WNW
RMY #1…………………13.8 WNW
RMY #2…………………14.4 WNW
RICHARDS (C5C)………….13.8

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.80 DEPARTURE…..+0.63
TOTAL PRECIPITATION FOR THE MONTH…………..0.80 DEPARTURE…..-0.53
TOTAL PRECIPITATION FOR THE YEAR (2025)…….36.62 DEPARTURE…..-3.38

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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

10/1  61/49/55/-3/0.00/668/97            30 NE  VEC1 30 NE  RMY 30
10/2  60/43/52/-6/0.00/637/91            28 NE  VEC1 28 NE  RMY 28
10/3  72/46/59/+2/0.00/670/96            23 SW  VEC1 23 SW  RMY 23
10/4  81/53/67/+10/0.00/667/96           18 NNW VEC1 18 NW  RMY 19
10/5  84/62/73/+16/0.00/664/96           18 SSW VEC1 18 SSW RMY 18
10/6  83/59/71/+15/0.00/649/94           25 SSW VEC1 25 SSW RMY 26
10/7  79/59/69/+13/0.00/440/64           35 SSW VEC1 35 SSW RMY 36
10/8  68/49/59/+4/0.80/027/04            33 NW  VEC1 34 SSW RMY 35 TSTM

10/9 The low since midnight is 41F, the daily normal low is 47F.

————————————————————–

OCTOBER DAILY RECORDS TO DATE

10/5 HIGH MINIMUM TEMPERATURE OF 62F,
TIED THE RECORD FOR THE DATE WITH 1910

10/6 HIGH MAXIMUM TEMPERATURE OF 83F,
TIED THE RECORD FOR THE DATE WITH 1990 AND 2007

————————————————————–

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)

RECORDS FOR OCTOBER 9
HIGH 82F IN 2011
LOW 29F IN 1907,1937
PRECIP 2.54 INCHES IN 1976
SNOWFALL TRACE IN 1988, 2001
PEAK GUST 81e MPH S IN 1976 (RECORD FOR MONTH)

RECORDS FOR OCTOBER 10
HIGH 85F IN 1949
LOW 27F IN 1929
PRECIP 2.02 INCHES IN 1998
SNOWFALL 6.8 INCHES IN 1979 (RECORD FOR MONTH)
PEAK GUST 59 MPH WNW IN 1958

TODAY’S REPORT PREPARED BY: Matt Douglas

Blue Hill Observatory & Science Center · Legal

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Please read the full Policy before accessing Observatory data · Effective January 1, 2025

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Effective January 1, 2025 · Milton, Massachusetts · bluehill.org
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Effective January 1, 2025 · Blue Hill Observatory & Science Center · Milton, Massachusetts