Monday, June 23, 2025

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

MONDAY, JUNE 23, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0408E
SUNSET:  1925E

DAY 2 OF THE HEAT-WAVE WITH RECORD HEAT AND OPPRESSIVELY HUMID
CONDITIONS TODAY….

Sunshine is baking us today with only a very thin veil of broken
cirrus high up in the sky not helping to filter the sun at all
through the morning. However, cumulus has developed early this
afternoon and is providing some periodic shade. Nonetheless it’s
still quite hot out there.

Temperatures quickly warmed into the 90s by late this morning after
starting the day in the low 70s. The record high for today’s date
is 93F which was set way back in 1888, we have tied that record
today (so far). Adding to the misery are dew point values in the
low to mid 70s creating oppressive conditions out there with heat
index values exceeding 100F. Definitely use extreme caution if
doing any physical activity outdoors today. Once again, an
Excessive Heat Warning is in effect until 8pm Tuesday.

As if the heat and humidity weren’t bad enough on their own, there
has been very little wind today to offer ventilation. The average
speed for the day so far is only around 7mph, but it has gone calm
at times during the mid to late morning hours. The peak gust so
far for the day is 16mph, which occurred just after 4am this
morning.

The visibility is somewhat limited again today by haze. The view
has been between 25-30 miles all day.

The maximum temperature for today is 93F degrees, which is 15
degrees above the normal high of 78F. The minimum temperature since
midnight is 71F degrees, which is 11 degrees above the normal low
of 60F.

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Today’s Observations:

7 A.M.
Weather: Thin broken cirrus
Temperature: 80F; Dew Point: 73F; Relative Humidity: 78%
Wind: NNW @ 3 kts, wind light
Sea-level pressure: 1019.5 mb; 30.11 in. Hg: rising, then falling
Visibility: 25 miles, hazy
6-hr Max temp: 80F
6-hr Min temp: 71F
24-hr Precip:  Trace
BHO SA 1155 E250 -BKN 25 195/80/73/3403/011/ HAZY WND LGT/ 8/001
50010 70000 10080 20071

10 A.M.
Weather: Thin broken cirrus, few cumulus distant SE-SW-NW,
few altocumulus distant WNW
Temperature: 88F; Dew Point: 73F; Relative Humidity: 74%; Heat Index: 96F
Wind: NNW @ 2kts, wind light and variable
Sea-level pressure: 1019.1 mb; 30.09 in. Hg: steady, then falling
Visibility: 30 miles, hazy
3-hr Precip: 0.00 inches
BHO SA 1455 E250 -BKN 30 191/88/73/3302/009/ FEW CU DSNT SE-SW-NW
FEW AC DSNT WNW HAZY WND L/V/ HX 96/ 8/251 58004

1 P.M.
Weather: Broken cumulus, thin broken cirrus
Temperature: 91F Dew Point: 75F; Relative Humidity: 59%; Heat Index: 102F
Wind: SW @ 5 kts, wind light
Sea-level pressure: 1018.3 mb; 30.07 in. Hg: falling, the more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 93F
6-hr Min temp: 80F
6-hr Precip:  0.00 inches
BHO SA 1755 E40 BKN 250 -BKN 30 183/91/75/2205/007/ HAZY WND LGT
HX 102/ 8/201 58008 10093 20080

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SUMMARY FOR SUNDAY, JUNE 22, 2025

TEMPERATURE (DEGREES F)
MAX…….91   NORMAL…..78
MIN…….68   NORMAL…..60
MEAN……80   NORMAL…..69

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………+11
TOTAL DEPARTURE FOR THE MONTH………………………+40 [+1.6 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…….-11
TOTAL HEATING UNITS FOR THE SEASON………….5665  DEPARTURE……-540
TOTAL HEATING UNITS LAST SEASON TO DATE……..5391  DEPARTURE……+274

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY…………….15  DEPARTURE…….+10
TOTAL COOLING UNITS FOR THE MONTH…………….94  DEPARTURE…….+28
TOTAL COOLING UNITS FOR THE SEASON…………..111  DEPARTURE…….+17
TOTAL COOLING UNITS LAST SEASON TO DATE………128  DEPARTURE…….-17

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)……….E32 W    @   11:47 A.M.
VECTOR #1 (1-Sec)……….32 W    @   11:47 A.M.
VECTOR #2 (1-Sec)……….33 NW   @   04:39 P.M.
DAVIS #1……………….32 W    @   12:02 P.M.
DAVIS #2 ………………33 W    @   11:59 A.M.
RMY #1 (Instantaneous)…..32 WNW  @   04:38 P.M.
RMY #2 (Instantaneous)…..34 W    @   12:02 P.M.
MERLIN…………………32 W
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………25 WNW  @   04:35 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..22      @   12:05 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..22      @   12:02 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………23 W    @   12:05 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………23 W    @   12:05 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..21 W    @   12:05 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..22 W    @   12:02 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..12.3 SW [295 total miles] VECTOR #1………………12.4
VECTOR #2………………13.2
DAVIS #1……………….12.3 W
DAVIS #2……………….13.0 W
RMY #1…………………12.1 W
RMY #2…………………13.1 WSW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….TRACE DEPARTURE…..-0.15
TOTAL PRECIPITATION FOR THE MONTH…………..1.43 DEPARTURE…..-2.11
TOTAL PRECIPITATION FOR THE YEAR (2025)…….23.17 DEPARTURE…..-2.97

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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  81/66/74/+6/0.00/…/..           52 WNW VEC1 52 WNW RMY 54
6/21  86/61/74/+6/0.00/…/..           22 NW  VEC1 22 NW  RMY 21
6/22  91/68/80/+11/0.03/…/..          32 W   VEC1 32 W   RMY 32

6/23 The low since midnight is 71F, the daily normal low is 60F.

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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 23
HIGH 93F IN 1888
LOW 45F IN 1885
PRECIP 0.76 INS IN 1893
PEAK GUST 63 MPH SE IN 1972 (AGNES)

RECORDS FOR JUNE 24
HIGH 91F IN 1914, 1976, 2013
LOW 40F IN 1932
PRECIP 2.80 INS IN 1929
PEAK GUST 54 MPH WNW IN 2010

TODAY’S REPORT PREPARED BY: MFD