Friday, June 20, 2025

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

FRIDAY, JUNE 20, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0407E
SUNSET:  1924E

SEASONABLE AND BREEZY FOR SUMMER SOLSTICE….

Today has been a beautiful day for the first day of summer.
Early this morning an air mass moved over the area bringing
dry air and giving us a break from those oppressive 70F dew
points (and 90F temperatures!). The sky has been scattered
with cumulus all day, with plenty of sunshine and blue sky.

Temperatures were in the upper 60s overnight but have been
slower to increase, even with all day sunshine. This is mostly
due to the significantly drier air, as well as the windy
conditions. Dew points have remained in the mid 50s today which
is much more tolerable.

It has been an incredibly busy day on the hill where wind is
concerned. Winds picked up during the overnight hours and
increased further during the early morning. The average speed
for the day so far is an impressive 21 mph, mostly out of the
west northwest. We have had frequent gusts over 35 mph for much
of the day. The peak gust so far is 52 mph and occurred at
10:44am.

With the arrival of dry air to the area, we were fortunate to
have around 40-50 miles of visibility for most of the day. While
the skies have not been hazy today, some pollen could be seen
near the horizon, keeping us from experiencing those crisp blue
skies.

The maximum temperature for today is 79F degrees, which is 2
degrees above the normal high of 77F. The minimum temperature
since midnight is 66F degrees, which is 8 degrees above the
normal low of 59F.

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Today’s Observations:

7 A.M.
Weather: Scattered cumulus
Temperature: 69F; Dew Point: 60F; Relative Humidity: 60%
Wind: W @ 22G35 kts, peak wind W 43 mph at 6:22 A.M.
Sea-level pressure: 1003.9 mb; 29.65 in. Hg: rising, then more
slowly
Visibility: 50 miles
6-hr Max temp: 69F
6-hr Min temp: 68F
24-hr Precip:  0.00 inches
BHO SA 1155 60 SCT 50 039/69/60/2722G35/965/ PK WND 2837/22/
8/200 51010 10069 20068

10 A.M.
Weather: Scattered cumulus
Temperature: 73F; Dew Point: 62F; Relative Humidity: 54%
Wind: WNW @ 24G38 kts, peak wind WNW 48 mph at 9:46 A.M.
Sea-level pressure: 1004.9 mb; 29.67 in. Hg: rising, then
steady
Visibility: 50 miles
3-hr Precip: 0.00 inches
BHO SA 1455 50 SCT 50 049/73/56/2924G38/967/ PK WND 2942/46
8/200 51010

1 P.M.
Weather: Scattered cumulus
Temperature: 79F Dew Point: 55F; Relative Humidity: 44%
Wind: WSW @ 20G35 kts, peak wind 50 mph at 12:00 P.M.
Sea-level pressure: 1007.5 mb; 29.75 in. Hg: rising, then
more slowly
Visibility: 40 miles
6-hr Max temp: 79F
6-hr Min temp: 69F
6-hr Precip:  0.00 inches
BHO SA 1755 70 SCT 40 075/79/55/2920G35/975/ PK WND 2843/00
8/200 51026 10079 20069

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SUMMARY FOR THURSDAY, JUNE 19, 2025

TEMPERATURE (DEGREES F)
MAX…….90   NORMAL…..77
MIN…….66   NORMAL…..59
MEAN……78   NORMAL…..68

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………+10
TOTAL DEPARTURE FOR THE MONTH………………………+17 [+0.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL HEATING UNITS FOR THE MONTH…………….50  DEPARTURE……..-7
TOTAL HEATING UNITS FOR THE SEASON………….5665  DEPARTURE……-537
TOTAL HEATING UNITS LAST SEASON TO DATE……..5390  DEPARTURE……+275

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY…………….13  DEPARTURE……..+9
TOTAL COOLING UNITS FOR THE MONTH…………….61  DEPARTURE……..+8
TOTAL COOLING UNITS FOR THE SEASON……………78  DEPARTURE……..-3
TOTAL COOLING UNITS LAST SEASON TO DATE………105  DEPARTURE…….-27

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)……….E31 SSW  @   04:07 P.M.
VECTOR #1 (1-Sec)……….31 SSW  @   04:07 P.M.
VECTOR #2 (1-Sec)……….31 SSW  @   04:06 P.M.
DAVIS #1……………….31 S    @   04:57 P.M.
DAVIS #2 ………………32 S    @   04:35 P.M.
RMY #1 (Instantaneous)…..31 SSW  @   03:12 P.M.
RMY #2 (Instantaneous)…..34 S    @   04:47 P.M.
MERLIN…………………42 W
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………22 SSW  @   03:12 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..22      @   03:12 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..22      @   03:12 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………21 S    @   03:13 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………23 S    @   04:08 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..22 SSW  @   03:12 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..23 SSW  @   03:12 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..11.0 SSW [263 total miles] VECTOR #1………………11.2
VECTOR #2………………11.7
DAVIS #1……………….10.8 SSW
DAVIS #2……………….11.7 SW
RMY #1…………………11.0 SW
RMY #2…………………11.8 SW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.16
TOTAL PRECIPITATION FOR THE MONTH…………..1.40 DEPARTURE…..-1.68
TOTAL PRECIPITATION FOR THE YEAR (2025)…….23.14 DEPARTURE…..-2.54

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PRELIMINARY CLIMATE SUMMARY FOR JUNE 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

6/1   63/47/55/-7/0.01/588/65           40 W   VEC1 40 W   RMY 42
6/2   70/48/59/-3/T/780/86              25 WNW VEC1 25 WSW RMY 26
6/3   79/50/65/+3/0.00/853/94           23 SSW VEC1 23 SSW RMY 21
6/4   84/58/71/+8/0.00/708/78           26 SW  VEC1 27 SW  RMY 28
6/5   93/61/77/+14/0.00/819/90          18 WSW VEC1 18 SW  RMY 19
6/6   81/63/72/+9/0.00/382/42           26 ENE VEC1 27 NE  RMY 27
6/7   71/60/66/+2/0.95/000/00           26 NE  VEC1 26 NE  RMY 25 TSTM
6/8   67/55/61/-3/0.00/347/38           22 ENE VEC1 21 ENE RMY 22
6/9   61/55/58/-6/0.01/000/00           20 E   VEC1 21 E   RMY 20
6/10  62/54/58/-7/0.20/000/00           21 W   VEC1 20 W   RMY 20
6/11  81/58/70/+5/0.00/850/93           32 WSW VEC1 32 WSW RMY 33
6/12  85/64/75/+10/0.00/814/89          47 WNW VEC1 47 WNW RMY 49
6/13  76/57/67/+1/T/631/69              20 E   VEC1 20 E   RMY 20
6/14  58/54/56/-10/0.09/000/00          24 NE  VEC1 24 NE  RMY 24
6/15  67/53/60/-6/0.00/449/49           18 E   VEC1 18 E   RMY 17
6/16  73/52/63/-4/0.00/641/70           20 SE  VEC1 20 ESE RMY 20
6/17  74/57/66/-1/0.12/028/03           22 S   VEC1 22 S   RMY 23
6/18  75/63/69/+2/0.02/018/02           22 SSW VEC1 23 SSW RMY 23
6/19  90/66/78/+10/0.00/…/..          31 SSW VEC1 31 SSW RMY 31

6/20 The low since midnight is 68F, the daily normal low is 59F.

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JUNE 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 JUNE 20
HIGH 94F IN 1953, 2024
LOW 41F IN 1918
PRECIP 2.61 INS 1945
PEAK GUST 63 MPH NE IN 1967, SSW IN 2010

RECORDS FOR JUNE 21
HIGH 94F IN 2012
LOW 42F IN 1940
PRECIP 1.40 INS 1903
PEAK GUST 51 MPH SSW IN 2000

TODAY’S REPORT PREPARED BY: Amanda Joly