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Sunday, May 31, 2026

May 31, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA   SUNDAY, MAY 31, 2026 ALL TIMES…

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BLUE HILL METEOROLOGICAL OBSERVATORY

MILTON, MASSACHUSETTS

ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

 

SUNDAY, MAY 31, 2026

ALL TIMES ARE IN EASTERN STANDARD TIME (EST)

SUNRISE: 0410E

SUNSET:  1914E

 

MUCH CALMER AND DRIER START TO THE DAY, SHOWERS DEVELOPING EARLY

THIS AFTERNOON….

 

An anomalous upper trough continues to sit to our northeast over

eastern Canada. A shortwave rotating around this trough is swinging

southeastward through New England today. This is resulted in the

quick increase in cloud cover and the development of showers now

pushing through the area this afternoon.

 

The day actually started with plenty of sunshine and it was a

very nice, albeit chilly, morning to be out and about. Clouds

quickly increased with showers developing shortly after noon-time

here at Blue Hill. They were very light up through 1pm with only

a trace being realized. However heavier showers have now moved

through since that time.

 

Temperatures started the day on the chilly side with a low this

morning of 39F, brr! Readings quickly recovered through the

morning reaching the mid to upper 60s by the late morning hours.

However, with the clouds taking over and rain showers moving

through, temperatures have dropped back into the mid to upper

50s. The dew point has spent most of the day in the mid 40s,

but has jumped to the low 50s now thanks to the rain.

 

Winds were fairly steady through the morning, then began to get

a bit gusty early this afternoon, especially in the vicinity of

showers. A west-northwest to northwest flow has been averaging

at around 9mph for the day so far. As mentioned, it has become

a bit gusty early this afternoon. The peak gust so far for the

day is 29mph, which occurred just after 12pm.

 

Visibility has been somewhat limited today due to haziness this

morning, and then rain showers in the area this afternoon. The

view was around 50 miles early this morning, but then generally

around 40 miles the remainder of the day, except locally lower

near showers.

 

The maximum temperature so far today is 69F degrees, which is

2 degrees below the normal high of 71F. The minimum temperature

since midnight is 39F degrees, which is 14 degrees below the

normal low of 53F.

 

————————————————————–

 

Today’s Observations:

 

7 A.M.

Weather: Broken cirrus, few cirrocumulus distant NNE-E

Temperature: 50F; Dew Point: 43F; Relative Humidity: 78%

Wind: NW @ 7 kts

Sea-level pressure: 1016.3 mb; 30.01 in. Hg: rising, then falling

Visibility: 50 miles

6-hr Max temp: 50F

6-hr Min temp: 39F

24-hr Precip: 0.86 inches

BHO SA 1155 E250 BKN 50 163/50/43/3107/001/ FEW CC DSNT NNE-E/

8/009 58003 70086 10050 20039

 

10 A.M.

Weather: Broken cirrus/cirrocumulus, few cumulus distant NNW,

few altocumulus distant SW-NW-NNE

Temperature: 64F; Dew Point: 45F; Relative Humidity: 49%

Wind: NW @ 6 kts, wind light and variable

Sea-level pressure: 1015.2 mb; 29.98 in. Hg: falling, then more rapidly

Visibility: 40 miles, hazy

3-hr Precip: 0.00 inches

BHO SA 1455 E250 BKN 40 152/64/45/3106/998/ FEW CU DSNT NNW

FEW AC DSNT SW-NW-NNE HAZY WND L/V/ 8/259 58011

 

1 P.M.

Weather: Broken cumulus, overcast altostratus/altocumulus, virga

all quadrants

Temperature: 66F; Dew Point: 46F; Relative Humidity: 49%

Wind: NW @ 11G19 kts

Sea-level pressure: 1013.2 mb; 29.92 in. Hg: falling, then more slowly

Visibility: 40 miles

6-hr Max temp: 69F

6-hr Min temp: 50F

6-hr Precip: Trace

BHO SA 1755 E65 BKN 85 OVC 40 132/66/46/3111G19/992/

VIRGA ALQDS RW-B02E16/ 8/27/ 56019 6000/ 10069 20050

 

————————————————————–

 

SUMMARY FOR SATURDAY, MAY 30, 2026

 

TEMPERATURE (DEGREES F)

MAX…….55   NORMAL…..70

MIN…….40   NORMAL…..52

MEAN……48   NORMAL…..61

 

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………-13

TOTAL DEPARTURE FOR THE MONTH……………………...+61 [+1.8 DEGREES/DAY]

 

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)

TOTAL HEATING UNITS FOR YESTERDAY…………….17  DEPARTURE…….+12

TOTAL HEATING UNITS FOR THE MONTH (MAY)………220  DEPARTURE…….-32

TOTAL HEATING UNITS FOR THE SEASON………….6056  DEPARTURE…….-83

TOTAL HEATING UNITS LAST SEASON TO DATE……..5607  DEPARTURE……+449

 

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)

TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-2

TOTAL COOLING UNITS FOR THE MONTH (MAY)……….53  DEPARTURE…….+30

TOTAL COOLING UNITS FOR THE SEASON……………59  DEPARTURE…….+33

TOTAL COOLING UNITS LAST SEASON TO DATE……….17  DEPARTURE…….+42

 

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)………..56 NNE  @   11:33 A.M.

                     VECTOR #1 (1-Sec)……….53 NNE  @   10:50 A.M.

                     VECTOR #2 (1-Sec)……….57 NNE  @   11:33 A.M.

                     DAVIS #1……………….52 NNE  @   11:33 A.M.

                     DAVIS #2 ………………49 NNE  @   10:31 A.M.

                     RMY #1 (Instantaneous)…..56 NNE  @   11:33 A.M.

                     RMY #2 (Instantaneous)…..57 NNE  @   11:33 A.M.

                     MERLIN…………………52 NNE

                     RICHARDS (C5C) (Inst)……52 NNE  @   11:33 A.M.

                     

FASTEST MILE:

CONTACTING ANEMOMETER/OFFICIAL………..…….34 NNE  @   11:35 A.M.

MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..32 NNE  @   11:35 A.M.

MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..34 NNE  @   11:35 A.M.

MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………34 NE   @   11:35 A.M.

MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………35 NE   @   11:35 A.M.

MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..31 NNE  @   11:35 A.M.

MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..33 NNE  @   11:35 A.M.

MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………32 NNE  @   11:35 A.M.  

 

AVERAGE WIND SPEED AND DIRECTION:

                     CONTACTING/OFFICIAL……..14.3 NNE [344 total miles]

                     VECTOR #1………………14.0

                     VECTOR #2………………14.8

                     DAVIS #1……………….14.4 NNE

                     DAVIS #2……………….13.8 NNE

                     RMY #1…………………13.7 N

                     RMY #2…………………14.3 N

                     RICHARDS (C5C)………….14.0

 

 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):

TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.86 DEPARTURE…..+0.73

TOTAL PRECIPITATION FOR THE MONTH (MAY)……..2.84 DEPARTURE…..-0.84

TOTAL PRECIPITATION FOR THE YEAR (2026)…….16.51 DEPARTURE…..-5.95

 

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/+1/0.01/071/08             22 N   VEC1 22 N   RMY 22        

5/22 61/47/54/-5/0.00/498/56             24 ENE VEC1 25 ENE RMY 24

5/23 62/49/56/-3/0.01/277/31             16 NE  VEC1 16 NE  RMY 16

5/24 52/48/50/-10/0.52/000/00            26 ESE VEC1 28 ESE RMY 27

5/25 74/52/63/+3/0.12/000/00             22 WNW VEC1 22 WNW RMY 22

5/26 82/56/69/+9/0.00/727/81             28 SSW VEC1 27 SW  RMY 29

5/27 84/62/73/+13/0.00/611/68            28 N   VEC1 27 NNW RMY 28

5/28 71/54/63/+2/T/666/74                36 NNW VEC1 36 N   RMY 36

5/29 71/50/61/0/0.01/414/46              30 NW  VEC1 31 SE  RMY 32

5/30 55/40/48/-13/0.88/054/06            56 NNE VEC1 53 NNE RMY 56

 

5/31 The low since midnight is 39F, the daily normal low is 53F.

 

————————————————————–

 

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 31

HIGH 92F IN 1944,1987,2013

LOW 35F IN 1961

PRECIP 5.02 INS 1984 (RECORD FOR MAY)

PEAK GUST 54e MPH WNW IN 1945

 

RECORDS FOR JUNE 1

HIGH 90F IN 1937,2013

LOW 36F IN 1945 [Record for month]

PRECIP 2.28 INS IN 1992

PEAK GUST 51e MPH SE IN 1952

lTODAY’S REPORT PREPARED BY: Matt Douglas

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