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Wednesday, May 13, 2026

May 13, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA WEDNESDAY, MAY 13, 2026 ALL TIMES ARE…

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

WEDNESDAY, MAY 13, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0425E
SUNSET:  1857E

CLOUDY AND COOL TODAY WITH PERIODS OF LIGHT RAIN….

A warm front is pushing through the region today bringing with it
a bit of light rain to the area during the morning hours. The rain
was quite light and wasn’t measurable. Just enough to barely wet
the ground at times. Now the rain has moved out for now with some
thinning of the clouds taking place early this afternoon. A bit of
sun will probably be seen this afternoon with temperatures warming
into the 60s.

Temperatures have been on the cool side so far with readings
only reaching the upper 50s so far today. With all the moisture
in the air, dew point values have been creeping up into the mid 40s.

Winds were on the light side during the morning, but have been
increasing out of the south as the warm front moves through. The
average speed for the day so far is around 10mph, but as mentioned
the trend is increasing. The peak gust so far for the day is
28mph, which occurred after the 1pm observation.

Visibility has been limited today due to thin fog and rain with
the view generally between 20-35 miles, but lower at times due to
the rain.

The maximum temperature so far today is 58F degrees, which is
6 degrees below the normal high of 66F. The minimum temperature
since midnight is 46F degrees, which is 1 degree below the
normal low of 47F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Broken altocumulus/altostratus, overcast cirrostratus,
few stratocumulus distant N-NNE
Temperature: 50F; Dew Point: 43F; Relative Humidity: 76%
Wind: SSW @ 5 kts, wind light
Sea-level pressure: 1019.1 mb; 30.09 in. Hg: falling, then rising
Visibility: 35 miles, hazy
6-hr Max temp: 50F
6-hr Min temp: 46F
24-hr Precip: 0.00 inches
BHO SA 1155 E80 BKN 200 OVC 35 191/50/43/2105/009/ FEW SC DSNT N-NNE
HAZY WND LGT/ 8/577 53004 10050 20046

10 A.M.
Weather: Scattered altocumulus, overcast altostratus, very light rain
Temperature: 52F; Dew Point: 46F; Relative Humidity: 80%
Wind: S @ 12 kts
Sea-level pressure: 1018.2 mb; 30.07 in. Hg: falling, then more slowly
Visibility: 20 miles, 15 miles W-N, thin fog
3-hr Precip: Trace
BHO SA 1455 E65 SCT 100 OVC 20R- 182/52/46/1912/007/ THN F ALQDS
PCPN VRY LGT VSBY 15 W-N/ 8/02/ 56009 6000/

1 P.M.
Weather: Scattered altocumulus, overcast cirrus, thin spots in overcast
OVHD-SSE-WSW, few stratocumulus distant WNW-N
Temperature: 58F; Dew Point: 46F; Relative Humidity: 64%
Wind: S @ 13G22 kts
Sea-level pressure: 1015.8 mb; 30.00 in. Hg: falling, then more rapidly
Visibility: 30 miles, hazy
6-hr Max temp: 58F
6-hr Min temp: 50F
6-hr Precip: Trace
BHO SA 1755 120 SCT 250 OVC 30 158/58/46/1913G22/000/ THN SPT IOVC
OVHD-SSE-WSW FEW SC DSNT WNW-N HAZY/ 8/552/ 58024 6000/ 10058 20050

————————————————————–

SUMMARY FOR TUESDAY, MAY 12, 2026

TEMPERATURE (DEGREES F)
MAX…….63   NORMAL…..66
MIN…….42   NORMAL…..47
MEAN……53   NORMAL…..57

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-4
TOTAL DEPARTURE FOR THE MONTH……………………….-1 [-0.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY…………….12  DEPARTURE……..+3
TOTAL HEATING UNITS FOR THE MONTH (MAY)………121  DEPARTURE……..-5
TOTAL HEATING UNITS FOR THE SEASON………….5957  DEPARTURE…….-56
TOTAL HEATING UNITS LAST SEASON TO DATE……..5478  DEPARTURE……+479

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH (MAY)………..0  DEPARTURE……..-5
TOTAL COOLING UNITS FOR THE SEASON…………….6  DEPARTURE……..-2
TOTAL COOLING UNITS LAST SEASON TO DATE………..7  DEPARTURE……..-1

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)………..29 WNW  @   02:40 P.M.
VECTOR #1 (1-Sec)……….29 WNW  @   02:40 P.M.
VECTOR #2 (1-Sec)……….30 WNW  @   02:40 P.M.
DAVIS #1……………….28 W    @   02:40 P.M.
DAVIS #2 ………………28 NW   @   02:40 P.M.
RMY #1 (Instantaneous)…..29 WNW  @   02:40 P.M.
RMY #2 (Instantaneous)…..30 WNW  @   02:40 P.M.
MERLIN…………………25 NW
RICHARDS (C5C) (Inst)……28 WNW  @   02:40 P.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………18 W    @   03:21 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..18 WNW  @   02:41 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..20 WNW  @   02:40 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………19 WNW  @   02:41 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………20 WNW  @   02:42 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..18 WNW  @   02:41 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..20 WNW  @   02:41 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………18 WNW  @   02:41 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.9 NNW [189 total miles] VECTOR #1……………….8.7
VECTOR #2……………….9.1
DAVIS #1………………….M
DAVIS #2………………….M
RMY #1………………….8.6 NW
RMY #2………………….8.9 NW
RICHARDS (C5C)…………..9.0

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.11
TOTAL PRECIPITATION FOR THE MONTH (MAY)……..0.69 DEPARTURE…..-0.76
TOTAL PRECIPITATION FOR THE YEAR (2026)…….14.36 DEPARTURE…..-5.87

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/…/..             28 WNW VEC1 27 WNW RMY 28
5/8  62/40/51/-4/0.00/…/..             33 W   VEC1 33 W   RMY 33
5/9  58/43/51/-5/0.35/…/..             30 SSW VEC1 31 SSW RMY 30
5/10 72/49/61/+5/T/…/..                28 SSW VEC1 28 SSW RMY 27
5/11 62/45/54/-2/T/…/..                26 NNW VEC1 26 NNW RMY 26
5/12 63/42/53/-4/T/…/..                29 WNW VEC1 29 WNW RMY 29

5/13 The low since midnight is 46F, 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 13
HIGH 85F IN 1947
LOW 32F IN 2020
PRECIP 2.39 INCHES IN 2006
PEAK GUST 49 MPH NNW IN 1965

RECORDS FOR MAY 14
HIGH 85F IN 1961,2022
LOW 33F IN 1895
PRECIP 1.93 INCHES IN 2006
PEAK GUST 53 MPH S IN 2009

TODAY’S REPORT PREPARED BY: Matt Douglas

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Blue Hill Observatory & Science Center · Legal

Data Use & Privacy Policy

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

Notice: By accessing, downloading, or using any Blue Hill Observatory data or services, you unconditionally accept and agree to be bound by this Policy in its entirety. If you do not agree, you may not access or use Observatory data.
Effective January 1, 2025 · Milton, Massachusetts · bluehill.org
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