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Monday, May 25, 2026

May 25, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA MONDAY, MAY 25, 2026 ALL TIMES ARE…

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

MONDAY, MAY 25, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0414E
SUNSET:  1909E

CLOUDS, FOG, AND RAIN THIS MORNING MOVE OUT WITH DRIER AND WARMER
CONDITIONS EARLY THIS AFTERNOON….

Weak low pressure passing across Northern New England is
currently moving out of Maine toward Nova Scotia. A cold front
trailing the low swept across the rest of New England this
morning bringing a band of light rain through the region. High
pressure to the west is building eastward toward New England
this afternoon and evening.

The day started with dense fog and drizzle, which then became a
steadier rain by mid morning which lasted for a couple of hours.
Rainfall yesterday amounted to 0.51″ for the 24 hours 7am to 7am.
An additional 0.12″ of rain fell this morning with the band of
rain. The rain has now moved out with drier conditions taking
over along with breaking cloud cover.

Temperatures are responding to the increasing insolation with
readings reaching the mid 60s early this afternoon. The air is
still on the humid side as the dew point has pushed into the low
60s as well.

Winds were light overnight into early this morning, even going
calm for a time. They have increased some from about the mid
morning period onward. The average speed so far for the day is
around 5mph, but it’s been closer to 9-10mph over the past few
hours. The peak gust so far is 22mph, which occurred twice,
first just after 9am and then again just after 11am.

Visibility was 3/4 of a mile or less through the morning, but
has improved markedly to around 70 miles following the frontal
passage.

The maximum temperature so far today is 67F degrees, which is 2
degrees below the normal high of 69F. The minimum temperature
since midnight is 52F degrees, which is 1 degree above the normal
low of 51F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 200ft
Temperature: 55F; Dew Point: 55F; Relative Humidity: 100%
Wind: Calm
Sea-level pressure: 1018.9 mb; 30.09 in. Hg: falling, then more rapidly
Visibility: 1/8 mile, fog
6-hr Max temp: 55F
6-hr Min temp: 53F
24-hr Precip: 0.51 inches
BHO SA 1155 X W2 1/8F 189/55/55/0000/009/ INTMT L-E21 WND CALM/
8//// 58014 6000/ 70051 10055 20053

10 A.M.
Weather: Sky obscured, vertical visibility 200ft, light rain
Temperature: 57F; Dew Point: 57F; Relative Humidity: 100%
Wind: W @ 5 kts, wind light
Sea-level pressure: 1017.8 mb; 30.06 in. Hg: falling, then more slowly
Visibility: 3/4 mile, fog
3-hr Precip: 0.10 inches
BHO SA 1455 X W2 3/4R-F 178/57/57/2805/006/ WND LGT/ 8////
56011 6010/

1 P.M.
Weather: Broken stratocumulus, broken altocumulus/altostratus
Temperature: 64F; Dew Point: 61F; Relative Humidity: 90%
Wind: W @ 8G17 kts
Sea-level pressure: 1016.8 mb; 30.03 in. Hg: falling, then more rapidly
Visibility: 70 miles
6-hr Max temp: 64F
6-hr Min temp: 55F
6-hr Precip: 0.12 inches
BHO SA 1755 E10 BKN 150 BKN 70 168/64/61/2808G17/003/ 8/570
58010 6012/ 10064 20055

————————————————————–

SUMMARY FOR SUNDAY, MAY 24, 2026

TEMPERATURE (DEGREES F)
MAX…….52   NORMAL…..69
MIN…….48   NORMAL…..51
MEAN……50   NORMAL…..60

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………-10
TOTAL DEPARTURE FOR THE MONTH………………………+47 [+1.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY…………….15  DEPARTURE……..+8
TOTAL HEATING UNITS FOR THE MONTH (MAY)………195  DEPARTURE…….-22
TOTAL HEATING UNITS FOR THE SEASON………….6031  DEPARTURE…….-73
TOTAL HEATING UNITS LAST SEASON TO DATE……..5583  DEPARTURE……+448

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH (MAY)……….41  DEPARTURE…….+26
TOTAL COOLING UNITS FOR THE SEASON……………47  DEPARTURE…….+29
TOTAL COOLING UNITS LAST SEASON TO DATE……….14  DEPARTURE…….+33

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)………..26 ESE  @   03:47 P.M.
VECTOR #1 (1-Sec)……….28 ESE  @   11:10 A.M.
VECTOR #2 (1-Sec)……….23 E    @   03:49 P.M.
DAVIS #1……………….26 ESE  @   11:10 A.M.
DAVIS #2 ………………24 E    @   03:47 P.M.
RMY #1 (Instantaneous)…..27 ESE  @   11:10 A.M.
RMY #2 (Instantaneous)…..24 E    @   02:34 P.M.
MERLIN…………………23 ESE
RICHARDS (C5C) (Inst)……26 ESE  @   11:10 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………17 ESE  @   03:51 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..19 ESE  @   03:48 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..17 E    @   03:50 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………19 E    @   03:48 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………18 E    @   03:50 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..19 ESE  @   03:48 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..17 E    @   03:50 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………19 ESE  @   03:48 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………9.7 E [232 total miles] VECTOR #1……………….9.5
VECTOR #2………………10.0
DAVIS #1……………….10.3 ESE
DAVIS #2……………….10.1 ESE
RMY #1………………….9.9 ENE
RMY #2…………………10.0 E
RICHARDS (C5C)………….10.2

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.51 DEPARTURE…..+0.38
TOTAL PRECIPITATION FOR THE MONTH (MAY)……..1.83 DEPARTURE…..-1.05
TOTAL PRECIPITATION FOR THE YEAR (2026)…….15.50 DEPARTURE…..-6.16

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……0.0
TOTAL SNOWFALL FOR THE MONTH (MAY)…………..0.0 DEPARTURE……0.0
TOTAL SNOWFALL FOR THE SEASON (2025-2026)……81.6 DEPARTURE….+11.9

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR MAY 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

5/1  63/43/53/0/0.00/769/91              26 WNW VEC1 27 NNW RMY 27
5/2  58/45/52/-2/0.04/127/15             29 SSW VEC1 29 SSW RMY 28
5/3  53/41/47/-7/T/119/14                37 NW  VEC1 36 NW  RMY 39
5/4  71/41/56/+2/0.00/775/91             46 SW  VEC1 46 SW  RMY 48
5/5  78/49/64/+9/0.00/718/84             43 SSW VEC1 43 SSW RMY 45
5/6  68/54/61/+6/0.08/146/17             43 SSW VEC1 42 SSW RMY 44
5/7  65/46/56/+1/0.22/697/81             28 WNW VEC1 27 WNW RMY 28
5/8  62/40/51/-4/0.00/741/86             33 W   VEC1 33 W   RMY 33
5/9  58/43/51/-5/0.35/000/00             30 SSW VEC1 31 SSW RMY 30
5/10 72/49/61/+5/T/346/40                28 SSW VEC1 28 SSW RMY 27
5/11 62/45/54/-2/T/191/22                26 NNW VEC1 26 NNW RMY 26
5/12 63/42/53/-4/T/835/96                29 WNW VEC1 29 WNW RMY 29
5/13 65/46/56/-1/T/122/14                41 S   VEC1 40 S   RMY 44
5/14 61/48/55/-2/0.26/000/00             37 SSE VEC1 38 SE  RMY 36
5/15 56/47/52/-5/0.04/026/03             18 NE  VEC1 19 NE  RMY 20
5/16 78/47/63/+5/0.00/853/97             33 SW  VEC1 34 SSW RMY 35
5/17 86/56/71/+13/0.05/827/94            39 W   VEC1 38 W   RMY 40
5/18 84/62/73/+15/0.00/829/94            33 SSW VEC1 32 SSW RMY 33
5/19 95/65/80/+22/0.25/716/81            47 NW  VEC1 47 NW  RMY 50 TSTM
5/20 89/65/77/+18/0.00/789/89            39 WNW VEC1 39 WNW RMY 41
5/21 68/52/60/+1/0.01/…/..             22 N   VEC1 22 N   RMY 22
5/22 61/47/54/-5/0.00/…/..             24 ENE VEC1 25 ENE RMY 24
5/23 62/49/56/-3/0.01/…/..             16 NE  VEC1 16 NE  RMY 16
5/24 52/48/50/-10/0.52/…/..            26 ESE VEC1 28 ESE RMY 27

5/25 The low since midnight is 52F, the daily normal low is 51F.

————————————————————–

MAY DAILY RECORDS TO DATE

5/19 RECORD HIGH MAXIMUM TEMPERATURE OF 95F,
BEATING THE PREVIOUS RECORD OF 91F SET IN 1962

————————————————————–

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

RECORDS FOR MAY 25
HIGH 91F IN 2007
LOW 37F IN 1967
PRECIP 3.73 INS IN 1967
PEAK GUST 83 MPH NE IN 1967 (RECORD FOR MAY)

RECORDS FOR MAY 26
HIGH 94F IN 2010
LOW 37F IN 1972,2013
PRECIP 1.73 INS IN 2003
SNOWFALL TRACE IN 1967 (Fell as ice pellets in nor’easter)
PEAK GUST 62 MPH NE IN 1967

TODAY’S REPORT PREPARED BY: Matt Douglas

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