Sunday, September 7, 2025

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

SUNDAY, SEPTEMBER 7, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0516E
SUNSET:  1807E

RAINY, RAW, AND COOL TODAY AS COLD FRONT LINGERS OFFSHORE ….

The rain was a big welcome as we were in a deficit until today.
Yesterday evening’s storm and through 7am EST netted a total of
1.22″ of rain. From 7am EST to 1pm EST we had an additional 0.76″
of rain. It has been a very soggy morning. There were few tree
branches on the roadways and some debris all over the summit this
morning, indicative of the strong winds that came through during
the storm in the evening.

Temperatures have not recovered much since the cold front moved
through last night. We went from 75F to 67F in an hour yesterday
and with the rain and overcast conditions, it has just not been
able to warm up at all. Our high for the day occurred at midnight
and our low so far was at 8:30am this morning. Even so, the spread
between the high and low is only 6 degrees, so today has had an
overall feeling of raw, humid, and just ick.

The wind was quite impressive during the storm yesterday evening
but since the cold front has passed through, the wind has been light
for much of the day. Yesterday’s peak gust was 55mph, which is
surprisingly not close to the record (78e mph in 1979). The wind
today has been mostly out of the north, which is much different
than the south-southwesterly flow we had over the past few days.
The average so far for the day is only around 7mph. The peak gust
so far is 16mph which occurred around 09:18am this morning.

We have been in the clouds all day today, as visibility has been
impacted heavily by the rain and foggy conditions. We only had
about 1/2 mile of visibility until the early afternoon. There was
marginal improvement by the final observation, with around 15 miles.

The maximum temperature so far today is 64F degrees, which is
12 degrees below the normal high of 76F. The minimum temperature
since midnight is 59 degrees, which is equal to the normal low.

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Today’s Observations:

7 A.M.
Weather: Rain showers, sky obscured, vertical visibility 200 ft
Temperature: 60F; Dew Point: 60F; Relative Humidity: 100%
Wind: N @ 5 kts, wind light
Sea-level pressure: 1017.7 mb; 30.05 in. Hg: rising unsteadily
Visibility: 1/2 mile, fog
6-hr Max temp: 60F
6-hr Min temp: 59F
24-hr Precip: 1.22 inches
BHO SA 1155 X W2 1/2RWF 177/60/60/3505/005/ WND LGT/ 8//// 52006
70122 10060 20059

10 A.M.
Weather: Rain showers, sky obscured, vertical visibility 200 ft
Temperature: 59F; Dew Point: 59F; Relative Humidity: 100%
Wind: NNW @ 7 kts
Sea-level pressure: 1018.1 mb; 30.01 in. Hg: rising, then falling
Visibility: 1/2 mile, fog
3-hr Precip: 0.62 inches
BHO SA 1455 X W2 1/2RWF 181/59/59/3407/006/ 8//// 50004 6062/

1 P.M.
Weather: Light rain showers, overcast stratus
Temperature: 59F Dew Point: 59F; Relative Humidity: 100%
Wind: ENE @ 4 kts, wind light
Sea-level pressure: 1018.0 mb; 30.06 in. Hg: rising, then
falling
Visibility: 15 miles, thin fog all quadrants
6-hr Max temp: 64F
6-hr Min temp: 59F
6-hr Precip: 0.76 inches
BHO SA 1755 E8 OVC 15RW- 180/59/59/0704/006/ THN F ALQDS VSBY
15 NE-E 25 ESE-S 20 SSW-WNW 10 NW-N WND LGT PCPN VRY LGT/ 8/6//
58001 6076/ 10064 20059

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SUMMARY FOR SATURDAY, SEPTEMBER 6, 2025

TEMPERATURE (DEGREES F)
MAX…….84   NORMAL…..76
MIN…….64   NORMAL…..59
MEAN……74   NORMAL…..68

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….+6
TOTAL DEPARTURE FOR THE MONTH……………………….+6 [+1.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL HEATING UNITS FOR THE MONTH……………..1  DEPARTURE……..-6
TOTAL HEATING UNITS FOR THE SEASON……………21  DEPARTURE……..-4
TOTAL HEATING UNITS LAST SEASON TO DATE……….14  DEPARTURE……..+7

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..9  DEPARTURE……..+5
TOTAL COOLING UNITS FOR THE MONTH…………….27  DEPARTURE……..+1
TOTAL COOLING UNITS FOR THE SEASON…………..699  DEPARTURE…….+77
TOTAL COOLING UNITS LAST SEASON TO DATE………714  DEPARTURE…….-15

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)………..55 W    @   04:56 P.M.
VECTOR #1 (1-Sec)……….55 W    @   04:55 P.M.
VECTOR #2 (1-Sec)……….67 W    @   04:55 P.M.
DAVIS #1……………….57 W    @   04:55 P.M.
DAVIS #2 ………………62 WNW  @   04:56 P.M.
RMY #1 (Instantaneous)…..57 W    @   04:56 P.M.
RMY #2 (Instantaneous)…..68 W    @   04:56 P.M.
MERLIN…………………55 W
RICHARDS (C5C) (Inst)……59 W    @   04:55 P.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………37 W    @   04:56 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..36 W    @   04:56 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..39 W    @   04:56 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………39 W    @   04:56 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………39 W    @   04:56 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..35 W    @   04:56 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..38 W    @   04:56 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………35 W    @   04:56 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..12.8 SSW [306 total miles] VECTOR #1………………12.8
VECTOR #2………………13.7
DAVIS #1……………….12.5 SSW
DAVIS #2……………….13.7 SSW
RMY #1…………………12.5 SW
RMY #2…………………13.7 SSW
RICHARDS (C5C)………….12.4

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..1.22 DEPARTURE…..+1.09
TOTAL PRECIPITATION FOR THE MONTH…………..1.34 DEPARTURE…..+0.63
TOTAL PRECIPITATION FOR THE YEAR (2025)…….32.67 DEPARTURE…..-2.65

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PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

9/1   73/55/64/-5/0.00/221/28            23 NE  VEC1 23 ENE RMY 23
9/2   77/58/68/-1/0.00/714/91            18 ESE VEC1 19 ESE RMY 18
9/3   78/57/68/0/0.00/719/92             21 SSW VEC1 21 SSW RMY 21
9/4   81/56/69/+1/0.00/…/..            26 SSW VEC1 27 SSW RMY 28
9/5   82/63/73/+5/0.12/…/..            30 SSW VEC1 31 SSW RMY 33
9/6   84/64/74/+6/…/…/..             55 W   VEC1 55 W   RMY 57

9/7 The low since midnight is 59F, the daily normal low is 59F.

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SEPTEMBER 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 7
HIGH 92F IN 2007, 2015, 2023
LOW 40F IN 1888
PRECIP 2.91 INCHES IN 1891
PEAK GUST 58e MPH W IN 1941

RECORDS FOR SEPTEMBER 8
HIGH 97F IN 2015
LOW 42F IN 1978
PRECIP 1.51 INCHES IN 2011
PEAK GUST 45 MPH S IN 2012

TODAY’S REPORT PREPARED BY: Amanda Joly