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Sunday, June 21, 2026

June 21, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SUNDAY, JUNE 21, 2026 ALL TIMES ARE…

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

SUNDAY, JUNE 21, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0407E
SUNSET:  1925E

A VERY PLEASANT WEATHER DAY FOR THE SUMMER SOLSTICE AND FATHER’S DAY….

Skies started the day off mainly clear with just some high
thin cirrus clouds around, mainly to the northwest. However,
much like yesterday, as the temperature rose, low level
convective clouds began to develop with a mix of cumulus and
cirrus into this afternoon. A few showers have also popped up
mainly to the north and west of the area. Regardless, it’s still
be a very nice day for any outdoor celebrations for dad.

Today is also the summer solstice, marking the day with the
longest day of daylight for the year. We have reached the latest
sunset as of today as well, but starting tomorrow, the sunrises
will start getting later, marking the beginning of our long trek
back toward winter.

Temperatures are a bit warmer than yesterday with readings
reaching 80F degrees early this afternoon. As has been the case
the last few days now, humidity levels remain comfortable with
dew point values holding in the mid 50s. We have really lucked
out so far this warm season with not having too many
oppressively humid days!

Winds are still busy today, but not as strong as the past 3
days. A general west-northwesterly flow has been averaging at
around 10mph for the day so far. The peak gust for the day so
far is “only” 24mph, which occurred after 1pm.

Visibility has been decent once again today with a view of 60-70
miles being the theme through the day. A good indicator of the
very delightful air over the region, especially for this time
of year.

The maximum temperature so far today is 80F degrees, which is
3 degrees above the normal high of 77F. The minimum temperature
since midnight is 58F degrees, which is 1 degree below the normal
low of 59F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Scattered cirrus, few altocumulus distant all quadrants
Temperature: 66F; Dew Point: 56F; Relative Humidity: 69%
Wind: WNW @ 5 kts, wind light
Sea-level pressure: 1010.7 mb; 29.85 in. Hg: rising, then more slowly
Visibility: 60 miles
6-hr Max temp: 66F
6-hr Min temp: 58F
24-hr Precip: 0.00 inches
BHO SA 1155 250 SCT 60 107/66/56/2905/985/ FEW AC DSNT ALQDS
WND LGT/ 8/052 51014 10066 20058

10 A.M.
Weather: Scattered cirrus, few cumulus all quadrants
Temperature: 75F; Dew Point: 55F; Relative Humidity: 50%
Wind: WNW @ 8G19 kts
Sea-level pressure: 1010.6 mb; 29.84 in. Hg: falling unsteadily
Visibility: 70 miles
3-hr Precip: 0.00 inches
BHO SA 1455 250 SCT 70 106/75/55/2908G19/984/ FEW CU ALQDS/
8/202 56001

1 P.M.
Weather: Broken cumulus, broken cirrus, cumulonimbus distant NNW-N,
virga WNW and distant NNW-ENE
Temperature: 80F; Dew Point: 54F; Relative Humidity: 41%
Wind: WNW @ 8G18 kts, wind W variable NW
Sea-level pressure: 1010.4 mb; 29.84 in. Hg: steady, then falling
Visibility: 60 miles
6-hr Max temp: 80F
6-hr Min temp: 66F
6-hr Precip: 0.00 inches
BHO SA 1755 E55 BKN 250 BKN 60 104/80/54/2908G18/984/
CB DSNT NNW-N VIRGA WNW AND DSNT NNW-ENE WND 27V31/ 8/303
58002 10080 20066

————————————————————–

SUMMARY FOR SATURDAY, JUNE 20, 2026

TEMPERATURE (DEGREES F)
MAX…….77   NORMAL…..77
MIN…….60   NORMAL…..59
MEAN……69   NORMAL…..68

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….+1
TOTAL DEPARTURE FOR THE MONTH……………………..+111 [+5.4 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 (JUN)……….17  DEPARTURE…….-42
TOTAL HEATING UNITS FOR THE SEASON………….6084  DEPARTURE……-119
TOTAL HEATING UNITS LAST SEASON TO DATE……..5665  DEPARTURE……+419

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY……………..4  DEPARTURE………0
TOTAL COOLING UNITS FOR THE MONTH (JUN)………125  DEPARTURE…….+68
TOTAL COOLING UNITS FOR THE SEASON…………..184  DEPARTURE…….+99
TOTAL COOLING UNITS LAST SEASON TO DATE……….87  DEPARTURE…….+97

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)………..40 WNW  @   10:02 A.M.
VECTOR #1 (1-Sec)……….39 WNW  @   01:07 P.M.
VECTOR #2 (1-Sec)……….41 NW   @   11:30 A.M.
DAVIS #1……………….39 W    @   10:02 A.M.
DAVIS #2 ………………38 WNW  @   01:30 P.M.
RMY #1 (Instantaneous)…..40 WNW  @   01:41 P.M.
RMY #2 (Instantaneous)…..42 NW   @   11:30 A.M.
MERLIN…………………38 NW
RICHARDS (C5C) (Inst)……39 WNW  @   10:02 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………26 WNW  @   01:43 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..26 WNW  @   10:03 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..29 WNW  @   10:02 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………28 W    @   10:03 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………28 WNW  @   10:03 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..25 WNW  @   10:03 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..28 WNW  @   10:02 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………25 WNW  @   10:03 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..15.8 WNW [378 total miles] VECTOR #1………………15.3
VECTOR #2………………16.4
DAVIS #1……………….16.1 WNW
DAVIS #2……………….15.5 WNW
RMY #1…………………15.0 WNW
RMY #2…………………15.9 WNW
RICHARDS (C5C)………….15.3

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.16
TOTAL PRECIPITATION FOR THE MONTH (JUN)……..1.10 DEPARTURE…..-2.14
TOTAL PRECIPITATION FOR THE YEAR (2026)…….17.90 DEPARTURE…..-7.94

————————————————————–

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  60/45/53/-9/T/606/67                26 ENE VEC1 27 ENE RMY 27
6/2  75/45/60/-2/0.00/680/75             22 NNW VEC1 22 NNW RMY 21
6/3  82/56/69/+7/0.00/880/97             28 S   VEC1 28 S   RMY 29
6/4  88/57/73/+10/0.00/817/90            23 WNW VEC1 23 SW  RMY 23
6/5  87/60/74/+11/0.00/810/89            20 NW  VEC1 19 NW  RMY 21
6/6  86/64/75/+12/0.09/282/31            46 WSW VEC1 45 WSW RMY 48
6/7  78/55/67/+3/0.26/446/49             38 NE  VEC1 38 NE  RMY 42
6/8  77/52/65/+1/0.00/904/99             20 SW  VEC1 20 SW  RMY 21
6/9  83/56/70/+6/0.00/886/97             28 W   VEC1 27 W   RMY 30
6/10 88/59/74/+9/0.00/686/75             30 SSW VEC1 30 SSW RMY 30
6/11 90/64/77/+12/0.10/631/69            22 WNW VEC1 22 WNW RMY 23
6/12 91/74/83/+18/0.00/412/45            21 WNW VEC1 21 WNW RMY 22
6/13 87/68/78/+12/0.00/769/84            36 NW  VEC1 36 NW  RMY 38
6/14 88/65/77/+11/0.00/495/54            33 SSW VEC1 32 SSW RMY 34
6/15 82/61/72/+6/0.00/577/63             28 SSW VEC1 28 SSW RMY 28
6/16 77/54/66/-1/0.00/898/98             22 W   VEC1 22 W   RMY 22
6/17 80/57/69/+2/0.00/697/76             25 SSW VEC1 24 SSW RMY 26
6/18 76/60/68/+1/0.64/193/21             51 S   VEC1 52 SSW RMY 54
6/19 78/60/69/+1/0.00/880/96             41 W   VEC1 40 W   RMY 41
6/20 77/60/69/+1/0.00/807/88             40 WNW VEC1 39 WNW RMY 40 TSTM

6/21 The low since midnight is 58F, the daily normal low is 60F.

————————————————————–

JUNE DAILY RECORDS TO DATE

6/12 NEW RECORD HIGH MINIMUM TEMPERATURE OF 74F;
BEATING OLD RECORD OF 69F SET IN 1942 AND 2017

6/18 RECORD PEAK WIND GUST OF 51 MPH,
BEATING THE OLD RECORD OF 48e MPH SET IN 1943

————————————————————–

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

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

RECORDS FOR JUNE 22
HIGH 93F IN 1921, 2012
LOW 43F IN 1940
PRECIP 1.57 INS IN 1900
PEAK GUST 74 MPH NW IN 1988

TODAY’S REPORT PREPARED BY: Matt Douglas

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Effective January 1, 2025 · Milton, Massachusetts · bluehill.org
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