Monday, August 4, 2025

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

MONDAY, AUGUST 4, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0440E
SUNSET:  1900E

CLEAR SKIES, BUT WILDFIRE SMOKE PERSISTS WITH VERY HAZY
CONDITIONS….

Today has once again featured skies that are perfectly clear
in terms of not a cloud in the sky, however wildfire smoke
from Canada is a bit worse today than yesterday creating a
very milky sky along with considerable haze in the air. Air
quality alerts are in effect into this evening.

Temperatures have inched slightly above normal again today
with readings reaching the mid 80s early this afternoon. Dew
point values are a bit higher today, so it feels a little more
humid. Readings have reached the mid 60s by late this morning
and into this afternoon.

The wind has been on the light and at times variable side
today. The average speed has only been around 8mph for the
day so far. Our peak gust is 17mph, which occurred around
3:30am this morning.

Visibility has been quite limited today thanks to haziness
from the increasing amounts of smoke. The view has been
decreasing as the day progresses, from around 30 miles early
this morning to only 10 miles by early this afternoon.

The maximum temperature so far today is 84F degrees, which is
2 degrees above the normal high of 82F. The minimum temperature
since midnight is 61F degrees, which is 3 degrees below the
normal low of 64F.

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Today’s Observations:

7 A.M.
Weather: Clear, smoke layer all quadrants
Temperature: 65F; Dew Point: 59F; Relative Humidity: 83%
Wind: SSW @ 4 kts, wind light
Sea-level pressure: 1021.4 mb; 30.16 in. Hg: rising, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 65F
6-hr Min temp: 61F
24-hr Precip:  0.00 inches
BHO SA 1155 CLR 30 214/65/59/2104/016/ K LYR ALQDS HAZY WND LGT/
8/000 53014 10065 20061

10 A.M.
Weather: Clear, smoke layer all quadrants
Temperature: 77F; Dew Point: 64F Relative Humidity: 64%
Wind: WNW @ 3 kts, wind light
Sea-level pressure: 1021.9 mb; 30.18 in. Hg: rising, then steady
Visibility: 25 miles, hazy
3-hr Precip: 0.00 inches
BHO SA 1455 CLR 25 219/77/64/3003/018/ K LYR ALQDS HAZY WND LGT/
8/000 51005

1 P.M.
Weather: Clear, smoke layer all quadrants
Temperature: 83F Dew Point: 64F; Relative Humidity: 52%
Wind: WNW @ 3 kts, wind light and variable
Sea-level pressure: 1021.1 mb; 30.15 in. Hg: falling, then more rapidly
Visibility: 10 miles, hazy
6-hr Max temp: 84F
6-hr Min temp: 65F
6-hr Precip:  0.00 inches
BHO SA 1755 CLR 10 211/83/64/3003/015/ K LYR ALQDS HAZY WND L/V/
8/000 58008 10084 20065

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SUMMARY FOR MONDAY, AUGUST 4, 2025

TEMPERATURE (DEGREES F)
MAX…….83   NORMAL…..82
MIN…….59   NORMAL…..64
MEAN……71   NORMAL…..73

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-2
TOTAL DEPARTURE FOR THE MONTH………………………-19 [-6.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH……………..0  DEPARTURE……..-1
TOTAL HEATING UNITS FOR THE SEASON…………….1  DEPARTURE……..-7
TOTAL HEATING UNITS LAST SEASON TO DATE………..0  DEPARTURE……..+1

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..6  DEPARTURE……..-2
TOTAL COOLING UNITS FOR THE MONTH……………..7  DEPARTURE…….-17
TOTAL COOLING UNITS FOR THE SEASON…………..518  DEPARTURE……+107
TOTAL COOLING UNITS LAST SEASON TO DATE………552  DEPARTURE…….-34

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)……….E21 SSW  @   06:38 P.M.
VECTOR #1 (1-Sec)……….21 SSW  @   06:38 P.M.
VECTOR #2 (1-Sec)……….21 SSW  @   06:38 P.M.
DAVIS #1……………….23 S    @   06:38 P.M.
DAVIS #2 ………………23 S    @   06:24 P.M.
RMY #1 (Instantaneous)…..21 SSW  @   05:46 P.M.
RMY #2 (Instantaneous)…..22 SSW  @   08:13 P.M.
MERLIN…………………19 S
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………15 S    @   08:12 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..15      @   08:20 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..15      @   05:52 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………15 S    @   08:20 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………17 S    @   08:20 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..14 SSW  @   06:39 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..15 S    @   08:19 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.4 SSW [178 total miles] VECTOR #1……………….8.0
VECTOR #2……………….8.3
DAVIS #1………………..7.7 SW
DAVIS #2………………..7.9 WSW
RMY #1………………….7.8 WSW
RMY #2………………….8.2 WSW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.13
TOTAL PRECIPITATION FOR THE MONTH…………..0.44 DEPARTURE…..+0.05
TOTAL PRECIPITATION FOR THE YEAR (2025)…….29.89 DEPARTURE…..-1.20

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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/…/..            28 NE  VEC1 28 NE  RMY 27
8/2   75/54/65/-8/0.00/…/..            18 NNW VEC1 18 NNW RMY 18
8/3   83/59/71/-2/0.00/…/..            21 SSW VEC1 21 SSW RMY 21

8/4 The low since midnight is 61F, the daily normal low is 64F.

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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 AUGUST 4
HIGH 96F IN 2022
LOW 48F IN 1900
PRECIP 1.68 INS IN 1983
PEAK GUST 67 MPH SSE IN 2020 [POST-TROPICAL STORM ISAIAS]

RECORDS FOR AUGUST 5
HIGH 98F IN 1955
LOW 48F IN 1929,1972
PRECIP 2.97 INCHES IN 1893
PEAK GUST 60e MPH SW 1977

TODAY’S REPORT PREPARED BY: MFD/JN