Sunday, July 13, 2025
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
SUNDAY, JULY 13, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0419E
SUNSET: 1920E
EARLY FOG QUICKLY BURNS OFF LEAVING EXCELLENT VISIBILITY DESPITE
MAINLY CLOUDY SKIES….
As has been the case pretty much every morning the past few days,
we started the morning with dense fog here on the summit and
visibility values under 1/4 mile. The fog burned off quickly however
with mainly cloudy skies being left behind. A few peeks of sun has
been seen here and there. The biggest surprise is the visibility
which shot up to around 60 miles by late this morning, a rarity for
this time of year, especially with the humidity levels still on the
high side.
Temperatures have warmed into the low to mid 80s by early this
afternoon. Dew point values have been fairly steady in the mid to
upper 60s, so it’s another warm and humid day.
The wind has been light yet again today. It’s been mostly out of the
south-southwest for the most part, although it’s been variable at
times. The average speed for the day so far is only around 6mph. The
peak gust for the day so far is 15mph, which occurred right before
noon.
Due to the morning foggy conditions we had limited visibility of
a 1/4 mile or less. Once the fog lifted the view improved markedly
to around 50-60 miles.
The maximum temperature so far today is 83F degrees, which is
1 degree above the normal high of 82F. The minimum temperature
since midnight is 63F degrees, which is 1 degree below the normal
low of 64F.
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Today’s Observations:
7 A.M.
Weather: Broken stratus fractus, overcast stratus, few breaks in
overcast distant S-SSW
Temperature: 68F; Dew Point: 66F; Relative Humidity: 95%
Wind: S @ 2 kts, wind light and variable
Sea-level pressure: 1021.7 mb; 30.17 in. Hg: rising, then more slowly
Visibility: 25 miles, thin fog
6-hr Max temp: 68F
6-hr Min temp: 63F
24-hr Precip: 0.00 inches
BHO SA 1155 E3 BKN 10 OVC 25 217/68/66/1802/017/ FEW BINOVC DSNT
S-SSW THN F ALQDS WND L/V/ 8/6// 51008 10068 20063
10 A.M.
Weather: Broken stratocumulus, broken altocumulus
Temperature: 76F; Dew Point: 67F; Relative Humidity: 74%
Wind: SSW @ 4 kts, wind light and variable
Sea-level pressure: 1021.8 mb; 30.17 in. Hg: steady, then rising
Visibility: 60 miles
3-hr Precip: 0.00 inches
BHO SA 1455 E17 BKN 130 BKN 60 218/76/67/2004/017/ WND L/V/
8/550 53001
1 P.M.
Weather: Broken cumulus, broken cirrus, fog bank distant NNE-NE
Temperature: 82F Dew Point: 69F; Relative Humidity: 64%
Wind: S @ 3 kts, wind light
Sea-level pressure: 1020.7 mb; 30.14 in. Hg: falling unsteadily
Visibility: 60 miles
6-hr Max temp: 83F
6-hr Min temp: 68F
6-hr Precip: 0.00 inches
BHO SA 1755 E20 BKN 250 BKN 60 207/82/69/1903/014/ F BNK DSNT
NNE-NE VSBY 20 NNE-NE WND LGT/ 8/201 57011 10083 20068
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SUMMARY FOR SATURDAY, JULY 12, 2025
TEMPERATURE (DEGREES F)
MAX…….84 NORMAL…..82
MIN…….65 NORMAL…..64
MEAN……75 NORMAL…..73
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….+2
TOTAL DEPARTURE FOR THE MONTH………………………+27 [+2.1 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……………..1 DEPARTURE……..-2
TOTAL HEATING UNITS FOR THE SEASON…………….1 DEPARTURE……..-2
TOTAL HEATING UNITS LAST SEASON TO DATE………..0 DEPARTURE……..+1
COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY…………….10 DEPARTURE……..+2
TOTAL COOLING UNITS FOR THE MONTH……………114 DEPARTURE…….+25
TOTAL COOLING UNITS FOR THE SEASON…………..314 DEPARTURE…….+86
TOTAL COOLING UNITS LAST SEASON TO DATE………312 DEPARTURE……..+2
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)……….E20 S @ 03:48 P.M.
VECTOR #1 (1-Sec)……….20 S @ 03:48 P.M.
VECTOR #2 (1-Sec)……….20 SSE @ 03:15 P.M.
DAVIS #1……………….20 S @ 03:48 P.M.
DAVIS #2 ………………23 S @ 03:45 P.M.
RMY #1 (Instantaneous)…..19 S @ 04:33 P.M.
RMY #2 (Instantaneous)…..20 SSE @ 03:15 P.M.
MERLIN…………………18 S
RICHARDS (C5C) (Inst)…..OTS
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………11 S @ 03:48 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..14 @ 03:17 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..15 @ 03:17 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………13 SSE @ 03:19 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………14 S @ 03:51 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..14 S @ 03:17 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..15 SSE @ 03:17 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………6.8 S [164 total miles]
VECTOR #1……………….7.4
VECTOR #2……………….7.8
DAVIS #1………………..6.8 S
DAVIS #2………………..7.2 S
RMY #1………………….7.2 S
RMY #2………………….7.8 S
RICHARDS (C5C)…………..OTS
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.12
TOTAL PRECIPITATION FOR THE MONTH…………..5.14 DEPARTURE…..+3.81
TOTAL PRECIPITATION FOR THE YEAR (2025)…….28.37 DEPARTURE…..-0.19
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PRELIMINARY CLIMATE SUMMARY FOR JULY 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
7/1 90/68/79/+8/0.14/411/45 38 W VEC1 38 W RMY 41 TSTM
7/2 85/69/77/+6/0.02/247/27 23 WSW VEC1 24 WSW RMY 24
7/3 88/63/76/+4/0.03/748/82 39 SW VEC1 39 SW RMY 40 TSTM
7/4 80/60/70/-2/0.00/875/96 28 NNW VEC1 27 NNW RMY 29
7/5 83/61/72/0/0.00/664/73 23 W VEC1 23 W RMY 24
7/6 92/65/79/+7/0.00/818/90 29 SW VEC1 29 SW RMY 29
7/7 88/69/79/+7/0.01/490/54 28 SSW VEC1 28 SSW RMY 29 TSTM
7/8 94/67/81/+9/0.36/562/62 24 WSW VEC1 24 WSW RMY 27 TSTM
7/9 74/65/70/-3/0.73/172/19 26 SW VEC1 27 SW RMY 28 TSTM
7/10 66/61/64/-9/3.85/…/.. 24 ENE VEC1 24 ENE RMY 24 TSTM
7/11 80/62/71/-2/0.00/…/.. 18 SSW VEC1 18 SSW RMY 18
7/12 84/65/75/+2/0.00/…/.. 20 S VEC1 20 S RMY 19
7/13 The low since midnight is 63F, the daily normal low is 64F.
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JULY DAILY RECORDS TO DATE
7/10 RECORD HIGHEST PRECIPITATION OF 3.85 INCHES;
BEATING OLD RECORD OF 1.95 INCHES SET IN 2015
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DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR JULY 13
HIGH 95F IN 1894
LOW 52F IN 1888, 1939, 1973
PRECIP 3.54 INS IN 1996
WIND 55 MPH SE IN 1996
RECORDS FOR JULY 14
HIGH 98F IN 1952
LOW 51F IN 1895, 1937
PRECIP 2.28 INS IN 1948
WIND 110e MPH NW IN 1942 [THUNDERSTORM GUST; RECORD FOR MONTH]
TODAY’S REPORT PREPARED BY: MFD
