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Friday, September 11, 2026

September 11, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA FRIDAY, SEPTEMBER 11, 2026 ALL TIMES ARE…

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

FRIDAY, SEPTEMBER 11, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0520E
SUNSET:  1801E

CLEARING SKIES AND SEASONABLE TEMPERATURES TO WELCOME THE WEEKEND….

Conditions started with mostly cloudy skies and then as the day
progressed we had additional clearing with just scattered high
level clouds present. It’s been a comfortable day with near
seasonable temperatures and lower dew points.

Temperatures have cooled off since yesterday, though as of 1pm
we are one degree above normal. Still though, it feels like a
very different day, as the dew points are down over 10F since
this time yesterday. Dew points have hovered in the low 50’s
throughout the day, and with a northern breeze it feels much
more like fall and less like summer for now.

Winds have been steady and not as active as yesterday. Our
average wind speed for yesterday was over 17mph and today is
around 10mph. The wind has mostly been out of the northwest and
west-northwest throughout the day. The peak gust for the day so
far is 23mph, which occurred just after 9am this morning.

Visibility started at around 60 miles today and slightly lowered
to 50 miles for the remainder of the observation shift.

The maximum temperature so far today is 76F, which is 1 degree
above the normal high of 75F. The minimum temperature since
midnight is 60F, which is 3 degrees above the normal low of 57F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, broken cirrus
Temperature: 61F; Dew Point: 52F; Relative Humidity: 72%
Wind: N @ 6 kts, wind light
Sea-level pressure: 1014.0 mb; 29.94 in. Hg: rising, then more slowly
Visibility: 60 miles
6-hr Max temp: 65F
6-hr Min temp: 60F
24-hr Precip: 0.00 inches
BHO SA 1155 120 SCT E250 BKN 60 140/61/52/3606/994/ SUN DMLY VSBL
WND LGT/ 8/051 51015 10065 20060

10 A.M.
Weather: Scattered cirrus, few altocumulus E-SSW and distant NW
Temperature: 71F; Dew Point: 53F; Relative Humidity: 54%
Wind: NW @ 8 kts
Sea-level pressure: 1015.0 mb; 29.97 in. Hg: rising, then more slowly
Visibility: 50 miles
3-hr Precip: 0.00 inches
BHO SA 1455 250 SCT 50 150/71/53/3108/997/ FEW AC E-SSW AND DSNT NW/
8/051 51010

1 P.M.
Weather: Scattered cirrus, few cumulus SSE-W
Temperature: 75F; Dew Point: 49F; Relative Humidity: 40%
Wind: NW @ 9 kts
Sea-level pressure: 1014.7 mb; 29.96 in. Hg: falling, then rising
Visibility: 50 miles
6-hr Max temp: 76F
6-hr Min temp: 61F
6-hr Precip: 0.00 inches
BHO SA 1755 250 SCT 50 147/75/49/3109/996/ FEW CU SSE-W/ 8/201 55003
10076 20061

————————————————————–

SUMMARY FOR THURSDAY, SEPTEMBER 10, 2026

TEMPERATURE (DEGREES F)
MAX…….84   NORMAL…..75
MIN…….67   NORMAL…..58
MEAN……76   NORMAL…..66

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………+10
TOTAL DEPARTURE FOR THE MONTH (SEP)………………….+1 [-0.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2026 THRU JUN 2027)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-2
TOTAL HEATING UNITS FOR THE MONTH (SEP)………..6  DEPARTURE……..-7
TOTAL HEATING UNITS FOR THE SEASON…………….9  DEPARTURE…….-22
TOTAL HEATING UNITS LAST SEASON TO DATE……….40  DEPARTURE…….-31

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY…………….11  DEPARTURE……..+8
TOTAL COOLING UNITS FOR THE MONTH (SEP)……….34  DEPARTURE……..-6
TOTAL COOLING UNITS FOR THE SEASON…………..788  DEPARTURE……+152
TOTAL COOLING UNITS LAST SEASON TO DATE………699  DEPARTURE…….+89

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)………..44 W    @   05:14 P.M.
VECTOR #1 (1-Sec)……….43 W    @   05:14 P.M.
VECTOR #2 (1-Sec)……….44 W    @   05:12 P.M.
DAVIS #1……………….44 W    @   05:15 P.M.
DAVIS #2 ………………40 WNW  @   05:17 P.M.
RMY #1 (Instantaneous)…..47 W    @   05:14 P.M.
RMY #2 (Instantaneous)…..44 W    @   05:12 P.M.
MERLIN…………………41 W
RICHARDS (C5C) (Inst)……42 W    @   05:14 P.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………30 WNW  @   05:16 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..29 WNW  @   05:16 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..31 W    @   05:17 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………31 W    @   05:15 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………31 WNW  @   05:17 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..29 WNW  @   05:16 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..30 W    @   05:17 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………28 WNW  @   05:44 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…….17.7 WNW [425 total miles] VECTOR #1……………..17.1
VECTOR #2……………..18.2
DAVIS #1………………17.7 W
DAVIS #2…………………M
RMY #1………………..16.7 W
RMY #2………………..17.7 W
RICHARDS (C5C)…………16.5

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.13
TOTAL PRECIPITATION FOR THE MONTH (SEP)……..1.03 DEPARTURE…..-0.16
TOTAL PRECIPITATION FOR THE YEAR (2026)…….27.02 DEPARTURE…..-8.78

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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

9/1  69/57/63/-6/0.21/008/01             15 SSW VEC1 15 E   RMY 14
9/2  76/58/67/-2/0.00/393/50             21 ESE VEC1 21 ESE RMY 20
9/3  74/60/67/-1/0.45/196/25             24 SSE VEC1 24 SSE RMY 23
9/4  84/63/74/+6/0.00/624/80             24 NNW VEC1 25 NNW RMY 24
9/5  71/60/66/-2/T/412/53                24 ENE VEC1 24 ENE RMY 25
9/6  69/53/61/-7/0.35/364/47             24 NE  VEC1 24 NNE RMY 27
9/7  79/52/66/-1/0.00/732/95             30 NW  VEC1 30 NW  RMY 30
9/8  80/58/69/+2/0.00/546/71             23 WNW VEC1 22 NNW RMY 24
9/9  80/58/69/+2/0.02/130/17             36 SSW VEC1 36 SSW RMY 36
9/10 84/67/76/+10/T/…/..               44 W   VEC1 43 W   RMY 47

9/11 The low since midnight is 60F, the daily normal low is 57F.

————————————————————–

SEPTEMBER DAILY RECORDS TO DATE

NONE.

————————————————————–

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

RECORDS FOR SEPTEMBER 11
HIGH 93F IN 1983, 2013
LOW 37F IN 1917
PRECIP 5.23 INCHES IN 1954 (HURRICANE EDNA)
PEAK GUST 101 MPH NW IN 1954 (HURRICANE EDNA)

RECORDS FOR SEPTEMBER 12
HIGH 92F IN 1961
LOW 42F IN 1958,1967,1985
PRECIP 2.79 INCHES IN 1960 (HURRICANE DONNA)
PEAK GUST 140 MPH SSE IN 1960 (HURRICANE DONNA)

TODAY’S REPORT PREPARED BY: Amanda Joly

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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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