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Monday, May 4, 2026

May 4, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA MONDAY, MAY 4, 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 4, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0435E
SUNSET:  1847E

SPRING HAS FINALLY RETURNED, PLENTY OF SUNSHINE AND WARMER
TEMPERATURES TODAY….

High pressure is building over the Atlantic just northwest of
Bermuda with a weak shortwave over northern New England tracking
eastward toward Atlantic Canada. With the high pressure to our
southeast, a brisk southwest flow has developed over the region
helping to advect a warmer air mass from the Midwest and Mid
Atlantic.

Skies have been mainly sunny today save for a bit of cloudiness
early this morning as the leftovers of the system from over the
weekend continue to move away.

Temperatures have warmed nicely to around 70 by early this
afternoon. The dew point has been holding in the low to mid 30s
which is creating relative humidity levels under 30% early this
afternoon. As a result, there is an elevated fire risk for today.

Winds have become quite gusty as the day has progressed. A west-
southwest to southwest wind has been averaging at around 15mph
for the day so far. Gusts have been exceeding 30mph for the past
few hours now. The peak gust so far is 46mph, which occurred
just after 10:30am this morning.

Visibility has been around 60 miles throughout the day to this
point.

The maximum temperature so far today is 70F degrees, which is 6
degrees above the normal high of 64F. The minimum temperature
since midnight is 41F degrees, which is 4 degrees below the
normal temperature of 45F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Broken altocumulus
Temperature: 53F; Dew Point: 32F; Relative Humidity: 43%
Wind: WSW @ 13G22 kts
Sea-level pressure: 1012.0 mb; 29.88 in. Hg: rising, then falling
Visibility: 60 miles
6-hr Max temp: 53F
6-hr Min temp: 32F
24-hr Precip: Trace
BHO SA 1155 E120 BKN 60 120/53/32/2413G22/988/ 8/050 50001
70000 10053 20043

10 A.M.
Weather: Scattered cirrus, few stratocumulus distant S-W-N
Temperature: 64F; Dew Point: 36F; Relative Humidity: 35%
Wind: WSW @ 17G29 kts, peak wind WSW 33mph at 09:54 A.M.
Sea-level pressure: 1010.7 mb; 29.85 in. Hg: steady, then falling
Visibility: 60 miles
3-hr Precip: 0.00 inches
BHO SA 1455 250 SCT 60 107/64/36/2517G29/985/ FEW SC DSNT S-W-N
PK WND 2529/54/ 8/501 58013

1 P.M.
Weather: Clear, few cumulus all quadrants, few cirrus distant NNW-N
Temperature: 69F; Dew Point: 34F; Relative Humidity: 27%
Wind: WSW @ 17G32 kts, peak wind SW 41mph at 12:13 P.M.
Sea-level pressure: 1009.2 mb; 29.80 in. Hg: falling, then more slowly
Visibility: 60 miles
6-hr Max temp: 70F
6-hr Min temp: 53F
6-hr Precip: 0.00 inches
BHO SA 1755 CLR 60 092/69/34/2517G32/980/ FEW CU ALQDS
FEW CI DSNT NNW-N PK WND 2336/13/ 8/201 56015 10070 20053

————————————————————–

SUMMARY FOR SUNDAY, MAY 3, 2026

TEMPERATURE (DEGREES F)
MAX…….53   NORMAL…..63
MIN…….41   NORMAL…..44
MEAN……47   NORMAL…..54

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-7
TOTAL DEPARTURE FOR THE MONTH……………………….-9 [-3.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY…………….18  DEPARTURE……..+7
TOTAL HEATING UNITS FOR THE MONTH (MAY)……….43  DEPARTURE……..+8
TOTAL HEATING UNITS FOR THE SEASON………….5879  DEPARTURE…….-43
TOTAL HEATING UNITS LAST SEASON TO DATE……..5409  DEPARTURE……+470

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)………..37 NW   @   04:57 P.M.
VECTOR #1 (1-Sec)……….36 NW   @   04:24 P.M.
VECTOR #2 (1-Sec)……….40 WNW  @   04:27 P.M.
DAVIS #1……………….34 NW   @   02:57 P.M.
DAVIS #2 ………………38 WNW  @   04:27 P.M.
RMY #1 (Instantaneous)…..39 NW   @   02:57 P.M.
RMY #2 (Instantaneous)…..43 NW   @   11:16 A.M.
MERLIN…………………35 NW
RICHARDS (C5C) (Inst)……38 NW   @   02:57 P.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………26 NW   @   04:57 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..25 NW   @   04:56 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..27 WNW  @   04:56 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………26 WNW  @   04:57 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………26 NW   @   04:56 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..25 NW   @   04:56 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..26 WNW  @   04:56 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………25 NW   @   04:56 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..13.0 NW [311 total miles] VECTOR #1………………12.9
VECTOR #2………………13.7
DAVIS #1……………….13.3 NW
DAVIS #2……………….12.8 NW
RMY #1…………………12.7 NW
RMY #2…………………13.2 NW
RICHARDS (C5C)………….13.1

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….TRACE DEPARTURE…..-0.12
TOTAL PRECIPITATION FOR THE MONTH (MAY)……..0.04 DEPARTURE…..-0.33
TOTAL PRECIPITATION FOR THE YEAR (2026)…….13.67 DEPARTURE…..-5.44

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/…/..              26 WNW VEC1 27 NNW RMY 27
5/2  58/45/52/-2/0.04/…/..             29 SSW VEC1 29 SSW RMY 28
5/3  53/41/47/-7/T/…/..                37 NW  VEC1 36 NW  RMY 39

5/4 The low since midnight is 41F, the daily normal low is 45F.

————————————————————–

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 4
HIGH 90F IN 2001
LOW 27F IN 1911 (RECORD FOR MAY)
PRECIP 1.67 INCHES IN 1893
SNOWFALL 0.1 INCHES IN 1920
PEAK GUST 60 MPH NW IN 1966

RECORDS FOR MAY 5
HIGH 92F IN 1949
LOW 30F IN 1891
PRECIP 2.74 INCHES IN 1922
SNOWFALL 3.0 INCHES IN 1917
PEAK GUST 58 MPH S IN 1966 & 58e MPH SW IN 1976

TODAY’S REPORT PREPARED BY: Matt Douglas

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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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