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Sunday, May 11, 2025

May 11, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SUNDAY, MAY 11, 2025 ALL TIMES ARE…

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

SUNDAY, MAY 11, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0427E
SUNSET:  1855E

SUNSHINE RETURNS ALONG WITH MILDER TEMPERATURES FOR MOTHER’S DAY….

The storm system that brought periods of rain, heavy at times,
starting Friday afternoon and ending yesterday afternoon brought a
storm total 1.44″ of much needed rainfall to Blue Hill. This has
allowed the monthly precipitation departure to reach 1.50″ above
normal. However, we are still running over a 3″ deficit for the
year to date.

Today is featuring much better weather with plenty of sunshine
being observed as a drier air mass has taken over the region.

Temperatures are quite a bit milder than they were yesterday
with readings getting into the mid to upper 60s. Dew point levels
which spent the morning in the low to mid 40s, have dropped into
the low to mid 30s early this afternoon. So the air is very
comfortable for any outdoor activities.

Winds were steady overnight into early this morning, but have
increased some as we approached the late morning and early afternoon
hours, thanks to mixing from aloft. The wind gradually veered from
the west to the northwest and north-northwest through the morning.
The average speed for the day so far is around 13mph. It has become
gusty with frequent gusts exceeding 25mph. The peak gust so far is
33mph which occurred just after noon time.

Visibility has been decent today with the view holding at around
60 miles all day.

The maximum temperature for today is 67F degrees, which is 1 degree
above the normal high of 66F. The minimum temperature since midnight
is 49F degrees, which is 2 degrees above the normal low of 47F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Clear, few altocumulus all quadrants
Temperature: 56F; Dew Point: 45F; Relative Humidity: 65%
Wind: WNW @ 8 kts
Sea-level pressure: 1020.5 mb; 30.14 in. Hg: rising, then more slowly
Visibility: 60 miles
6-hr Max temp: 56F
6-hr Min temp: 49F
24-hr Precip:  0.08 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 CLR 60 205/56/45/3008/014/ FEW AC ALQDS/ 8/050 51023
70008 10056 20049

10 A.M.
Weather: Clear, few stratocumulus all quadrants, few cirrus all quadrants
Temperature: 64F; Dew Point: 43F; Relative Humidity: 46%
Wind: NW @ 13G23 kts
Sea-level pressure: 1022.0 mb; 30.18 in. Hg: rising, then more slowly
Visibility: 60 miles
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 CLR 60 220/64/43/3213G23/018/ FEW SC ALQDS FEW CI ALQDS/
8/501 51015

1 P.M.
Weather: Clear, few cirrus all quadrants
Temperature: 67F Dew Point: 32F; Relative Humidity: 27%
Wind: NW @ 14G23 kts, peak wind NNW 33mph at 12:14 P.M.
Sea-level pressure: 1022.2 mb; 30.19 in. Hg: rising, then falling
Visibility: 60 miles
6-hr Max temp: 67F
6-hr Min temp: 56F
6-hr Precip:  0.00 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 CLR 60 222/67/32/3214G23/019/ FEW CI ALQDS PK WND 3329/14/
8/001 50002 10067 20056

————————————————————–

SUMMARY FOR SATURDAY, MAY 10, 2025

TEMPERATURE (DEGREES F)
MAX…….62   NORMAL…..65
MIN…….45   NORMAL…..47
MEAN……54   NORMAL…..56

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-2
TOTAL DEPARTURE FOR THE MONTH………………………+37 [+3.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….11  DEPARTURE……..+1
TOTAL HEATING UNITS FOR THE MONTH…………….70  DEPARTURE…….-38
TOTAL HEATING UNITS FOR THE SEASON………….5468  DEPARTURE……-527
TOTAL HEATING UNITS LAST SEASON TO DATE……..5269  DEPARTURE……+199

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH……………..4  DEPARTURE………0
TOTAL COOLING UNITS FOR THE SEASON…………….7  DEPARTURE………0
TOTAL COOLING UNITS LAST SEASON TO DATE………..2  DEPARTURE……..+5

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)………..36 NW   @   01:27 P.M.
VECTOR #1 (1-Sec)……….37 NW   @   01:27 P.M.
VECTOR #2 (1-Sec)……….35 NW   @   01:26 P.M.
DAVIS #1……………….34 WNW  @   01:27 P.M.
DAVIS #2 ………………30 WNW  @   01:24 P.M.
RMY #1 (Instantaneous)…..41 NW   @   01:27 P.M.
RMY #2 (Instantaneous)…..35 NW   @   01:26 P.M.
MERLIN…………………34 NW
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………21 WNW  @   04:47 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..21      @   03:20 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..22      @   01:28 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………23 WNW  @   01:28 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………21 NW   @   01:28 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..21 NW   @   03:21 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..21 NW   @   01:28 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..11.9 NW [286 total miles] VECTOR #1………………11.7
VECTOR #2………………12.5
DAVIS #1……………….12.1 NW
DAVIS #2……………….12.2 NNW
RMY #1…………………11.4 NW
RMY #2…………………12.2 NW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.08 DEPARTURE…..-0.03
TOTAL PRECIPITATION FOR THE MONTH…………..2.72 DEPARTURE…..+1.50
TOTAL PRECIPITATION FOR THE YEAR (2025)…….16.84 DEPARTURE…..-3.16

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE…….0.0
TOTAL SNOWFALL FOR THE MONTH………………..0.0 DEPARTURE…….0.0
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……35.8 DEPARTURE…..-33.9

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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   69/43/56/+3/0.00/0.0/744/88        28 S   VEC1 28 SSW RMY 28
5/2   79/47/63/+9/0.19/0.0/339/40        28 SE  VEC1 29 SE  RMY 25 TSTM
5/3   84/54/69/+15/0.15/0.0/561/66       43 SSW VEC1 42 SSW RMY 44 TSTM
5/4   77/50/64/+10/0.06/0.0/256/30       33 SW  VEC1 34 SW  RMY 32
5/5   50/46/48/-7/0.26/0.0/000/00        35 ENE VEC1 35 ENE RMY 36
5/6   61/48/55/0/0.57/0.0/000/00         26 S   VEC1 27 ENE RMY 27
5/7   72/54/63/+8/0.01/0.0/310/36        33 SSW VEC1 33 SW  RMY 35
5/8   74/51/63/+8/0.04/0.0/…/..        18 ESE VEC1 18 ESE RMY 18
5/9   51/46/49/-7/1.15/0.0/…/..        33 E   VEC1 34 ENE RMY 35
5/10  62/45/54/-2/0.29/0.0/…/..        36 NW  VEC1 37 NW  RMY 41

5/11 The low since midnight is 49F, the daily normal low is 47F.

————————————————————–

MAY DAILY RECORDS TO DATE

NONE.

————————————————————–

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

RECORDS FOR MAY 11
HIGH 90F IN 1993
LOW 28F IN 1900
PRECIP 1.28 INS IN 1957
SNOW 1.0 INS IN 1907 (LATEST MEASURABLE SNOW ON RECORD)
PEAK GUST 75e MPH NW IN 1945

RECORDS FOR MAY 12
HIGH 88F IN 2001
LOW 29F IN 1907
PRECIP 1.49 INCHES IN 1968
SNOW TRACE IN 2019
PEAK GUST 76 MPH S IN 1974

TODAY’S REPORT PREPARED BY: MFD

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Data Use & Privacy Policy

Please read the full Policy before accessing Observatory data · Effective January 1, 2025

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