Wednesday, September 30, 2026

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

WEDNESDAY, SEPTEMBER 30, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0540E
SUNSET:  1727E

OVERCAST SKIES HANG ON, BUT MILD WITH VERY LITTLE WIND TODAY….

We just can’t seem to shake the clouds despite the weekend storm
being long gone from the area. Warming aloft is creating a fairly
strong inversion over the region which is trapping low level
clouds underneath. With the lower sun angle, it’s getting harder
to burn them off. Either way, it’s milder today than it has been
the prior few days with very little wind to speak of out there.

Believe it or not, we picked up a little bit more rain yesterday
afternoon through early this morning. An additional 0.03″ was
received overnight, with another 0.01″ occurring after 7am this
morning in drizzle. This increases our monthly total to 11.53″
through 1pm this afternoon. This still ranks as the 2nd Wettest
September on record going back to 1885. Here are the rankings.

BHO Wettest Septembers, inches (1885-2026):

1) 12.37 1999
2) 11.53 2026 (thru 1pm EST 9/30)
3) 11.04 1933
4) 10.23 1896
5) 10.00 1961
6) 9.62 1987
7) 9.58 1888
8) 9.36 1918
9) 9.25 2018
10) 8.81 1907

Temperatures are a bit milder today than it has been the past
few days. Readings have reached the mid 60s early this afternoon.
Dew points have remained elevated as well making it feel a bit
humid out there today. This will be the theme through tomorrow
as well as the dew point climbs to the mid 60s.

The wind has been very light today, only averaging at around 4
mph for the day so far. It was rather variable during the early
hours of the day, but has seemingly settled out of the west-
southwest this afternoon. The peak gust (or lack thereof) is a
measly 11mph, which occurred around 12:15am this morning.

Visibility was very limited early this morning due to fog, but
improved nicely by mid to late morning. The view went from around
1/8th of a mile early this morning to 40-50 miles by late this
morning and early this afternoon.

The maximum temperature so far today is 67F, which is 1 degree
below the normal high of 68F. The minimum temperature since
midnight is 57F, which is 6 degrees above the normal low of 51F.

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Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 300ft, light drizzle
Temperature: 58F; Dew Point: 58F; Relative Humidity: 100%
Wind: WSW @ 3 kts, wind light
Sea-level pressure: 1020.3 mb; 30.13 in. Hg: rising, then more rapidly
Visibility: 1/8 mile, fog
6-hr Max temp: 58F
6-hr Min temp: 57F
24-hr Precip: 0.03 inches
BHO SA 1155 X W3 1/8L-F 203/58/58/2403/013/ WND LGT/ 8//// 53017
6002/ 70003 10058 20057

10 A.M.
Weather: Overcast stratocumulus, few lower stratus fractus NE-S
Temperature: 61F; Dew Point: 61F; Relative Humidity: 98%
Wind: WSW @ 3 kts, wind light
Sea-level pressure: 1020.4 mb; 30.13 in. Hg: rising, then falling
Visibility: 30 miles
3-hr Precip: 0.01 inches
BHO SA 1455 E10 OVC 30 204/61/61/2403/013/ FEW LWR STFRA NE-S
WND LGT/ 8/5// 50001 6001/

1 P.M.
Weather: Broken stratocumulus, overcast altostratus, few breaks in
overcast all quadrants
Temperature: 67F; Dew Point: 61F; Relative Humidity: 81%
Wind: SW @ 3 kts, wind light
Sea-level pressure: 1019.3 mb; 30.10 in. Hg: falling, then more rapidly
Visibility: 50 miles, hazy
6-hr Max temp: 67F
6-hr Min temp: 58F
6-hr Precip: 0.01 inches
BHO SA 1755 E15 BKN 35 OVC 50 193/67/61/2303/010/ FEW BINOVC ALQDS
HAZY WND LGT/ 8/52/ 58011 6001/ 10067 20058

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SUMMARY FOR TUESDAY, SEPTEMBER 29, 2026

TEMPERATURE (DEGREES F)
MAX…….63   NORMAL…..68
MIN…….52   NORMAL…..51
MEAN……58   NORMAL…..59

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-1
TOTAL DEPARTURE FOR THE MONTH (SEP)…………………-46 [-1.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2026 THRU JUN 2027)
TOTAL HEATING UNITS FOR YESTERDAY……………..7  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH (SEP)………115  DEPARTURE…….+22
TOTAL HEATING UNITS FOR THE SEASON…………..118  DEPARTURE……..+7
TOTAL HEATING UNITS LAST SEASON TO DATE……….61  DEPARTURE…….+57

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY……………..0  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH (SEP)……….51  DEPARTURE…….-23
TOTAL COOLING UNITS FOR THE SEASON…………..805  DEPARTURE……+136
TOTAL COOLING UNITS LAST SEASON TO DATE………736  DEPARTURE…….+69

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)………..20 NNW  @   12:06 A.M.
VECTOR #1 (1-Sec)……….20 NNW  @   12:01 A.M.
VECTOR #2 (1-Sec)……….21 NW   @   12:50 A.M.
DAVIS #1……………….20 NNW  @   12:01 A.M.
DAVIS #2 ………………19 NNW  @   12:35 A.M.
RMY #1 (Instantaneous)…..21 NNW  @   12:01 A.M.
RMY #2 (Instantaneous)…..21 NW   @   12:33 A.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)……20 NNW  @   12:06 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………13 NNW  @   12:28 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..15 NNW  @   12:02 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..14 NW   @   12:18 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………15 NNW  @   12:03 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………14 NNW  @   12:37 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..15 NNW  @   12:02 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..14 NW   @   12:37 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………15 NNW  @   12:02 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..5.3 NW [126 total miles] VECTOR #1………………6.9
VECTOR #2………………7.1
DAVIS #1……………….6.6 NW
DAVIS #2…………………M
RMY #1…………………6.8 NW
RMY #2…………………6.8 NW
RICHARDS (C5C)………….7.3

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.03 DEPARTURE…..-0.12
TOTAL PRECIPITATION FOR THE MONTH (SEP)…….11.52 DEPARTURE…..+7.62
TOTAL PRECIPITATION FOR THE YEAR (2026)…….37.51 DEPARTURE…..-1.00

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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/641/84               44 W   VEC1 43 W   RMY 47
9/11 77/59/68/+2/0.00/654/86             23 NW  VEC1 23 NW  RMY 25
9/12 77/55/66/0/0.00/667/88              23 SSW VEC1 23 SSW RMY 22
9/13 67/60/64/-1/0.98/000/00             25 SE  VEC1 26 SE  RMY 24
9/14 72/53/63/-2/T/572/76                32 NNW VEC1 32 NNW RMY 34
9/15 68/48/58/-7/0.00/727/97             18 S   VEC1 18 SE  RMY 18
9/16 78/53/66/+2/0.00/522/70             21 SW  VEC1 21 WSW RMY 21
9/17 82/63/73/+9/0.03/394/53             25 SW  VEC1 25 SW  RMY 27
9/18 79/58/69/+6/T/636/86                26 N   VEC1 26 NNW RMY 27
9/19 63/50/57/-6/0.00/531/72             21 N   VEC1 20 N   RMY 20
9/20 61/51/56/-7/0.11/000/00             21 SSE VEC1 22 SSE RMY 21
9/21 64/51/58/-4/0.11/542/74             24 ENE VEC1 23 ENE RMY 23
9/22 60/52/56/-6/0.00/481/66             32 ENE VEC1 32 ENE RMY 33
9/23 63/50/57/-5/0.00/566/78             39 ENE VEC1 38 ENE RMY 39
9/24 61/46/54/-7/0.00/607/84             35 NE  VEC1 33 ENE RMY 35
9/25 61/48/55/-6/0.05/000/00             46 NE  VEC1 45 NE  RMY 47
9/26 58/52/55/-5/3.35/000/00             58 NE  VEC1 58 NE  RMY 58
9/27 59/53/56/-4/5.15/000/00             52 NE  VEC1 51 NE  RMY 54
9/28 56/52/54/-5/0.66/000/00             36 NNE VEC1 35 NNE RMY 35
9/29 63/52/58/-1/0.03/007/01             20 NNW VEC1 20 NNW RMY 21

9/30 The low since midnight is 57F, the daily normal low is 50F.

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SEPTEMBER DAILY RECORDS TO DATE

9/26 RECORD PEAK WIND GUST OF 58 MPH NE,
BEATING THE OLD RECORD OF 54 MPH S SET IN 1977

9/27 RECORD DAILY RAINFALL OF 5.15 INCHES,
BEATING THE OLD RECORD OF 2.26 INCHES SET IN 1962

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

RECORDS FOR SEPTEMBER 30
HIGH 84F IN 1986
LOW 31F IN 1992
PRECIP 2.44 INCHES IN 2015
PEAK GUST 71 MPH S IN 2020

RECORDS FOR OCTOBER 1
HIGH 85F IN 1927
LOW 30F IN 1992
PRECIP 1.63 INCHES IN 2014
PEAK GUST 68e MPH SSE IN 1977

TODAY’S REPORT PREPARED BY: Matt Douglas