Saturday, July 18, 2026

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

SATURDAY, JULY 18, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0423E
SUNSET:  1917E

SMOKE RETURNS ALONG WITH INCREASING CLOUDS AND DEVELOPING SHOWERS…

We started the day with a bit of hazy sunshine as both the smoke
and mid level clouds were just starting to increase. By late this
morning, the smoke increased enough to prevent the sun from being
able to burn via our sunshine recorder. By early this morning,
clouds had also thickened along with a few scattered showers
moving through.

Temperatures were at comfortable levels throughout the day, however
humidity levels did increase. The low temperature early this morning
was 65F, and it rose to 80F by late this morning before settling
back with the increased cloud cover. The dew point gradually rose
from the low 60s to the mid 60s through the course of the morning
and early afternoon.

Winds were steady during the very early part of the day, but
increased by the mid morning hours. A generally southwest to south-
southwest flow has been averaging at around 12mph for the day so
far. It became rather gusty by the mid morning with frequent gusts
in the 25-30mph range. The peak gust for the day so far is 31mph,
which occurred just before 1:20pm this afternoon.

Visibility has been quite limited all day due to haziness from the
smoke. The view has been generally between 8-10 miles all day so
far.

The maximum temperature so far today is 80F, which is 2 degrees
below the normal high of 82F. The minimum temperature since
midnight is 65F, which is 1 degree above the normal low of 64F.

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Today’s Observations:

7 A.M.
Weather: Broken cirrus, few altocumulus distant NNE-E,
smoke layer all quadrants
Temperature: 70F; Dew Point: 62F; Relative Humidity: 76%
Wind: SW @ 8 kts
Sea-level pressure: 1016.4 mb; 30.01 in. Hg: falling, then rising
Visibility: 10 miles, hazy
6-hr Max temp: 70F
6-hr Min temp: 65F
24-hr Precip: 0.00 inches
BHO SA 1155 E250 BKN 10 164/70/62/2208/001/ FEW AC DSNT NNE-E
K LYR ALQDS HAZY/ 8/051 55005 10070 20065

10 A.M.
Weather: Broken cirrus, smoke layer all quadrants
Temperature: 79F; Dew Point: 64F; Relative Humidity: 60%
Wind: S @ 12G21 kts
Sea-level pressure: 1013.9 mb; 29.94 in. Hg: falling, then more rapidly
Visibility: 9 miles, hazy
3-hr Precip: 0.00 inches
BHO SA 1455 E250 BKN 9 139/79/64/1912G21/994/ K LYR ALQDS HAZY/
8/001 58025

1 P.M.
Weather: Overcast altocumulus, smoke layer all quadrants
Temperature: 74F; Dew Point: 66F; Relative Humidity: 74%
Wind: SSW @ 15G26 kts, peak wind S 30mph at 12:51 P.M.
Sea-level pressure: 1011.8 mb; 29.88 in. Hg: falling, then more rapidly
Visibility: 9 miles, hazy
6-hr Max temp: 80F
6-hr Min temp: 70F
6-hr Precip: Trace
BHO SA 1755 E130 OVC 9 118/74/66/2015G26/988/ K LYR ALQDS
HAZY PK WND 1926/51/ 8/05// 58021 6000/ 10080 20070

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SUMMARY FOR FRIDAY, JULY 17, 2026

TEMPERATURE (DEGREES F)
MAX…….83   NORMAL…..82
MIN…….61   NORMAL…..64
MEAN……72   NORMAL…..73

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….-1
TOTAL DEPARTURE FOR THE MONTH………………………+62 [+3.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2026 THRU JUN 2027)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE………0
TOTAL HEATING UNITS FOR THE MONTH (JUL)………..2  DEPARTURE……..-2
TOTAL HEATING UNITS FOR THE SEASON…………….2  DEPARTURE……..-2
TOTAL HEATING UNITS LAST SEASON TO DATE………..1  DEPARTURE……..+1

COOLING DEGREE DAYS (SEASON: JAN 2026 THRU DEC 2026)
TOTAL COOLING UNITS FOR YESTERDAY……………..7  DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH (JUL)………190  DEPARTURE…….+60
TOTAL COOLING UNITS FOR THE SEASON…………..429  DEPARTURE……+160
TOTAL COOLING UNITS LAST SEASON TO DATE………380  DEPARTURE…….+49

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)………..28 NW   @   09:48 A.M.
VECTOR #1 (1-Sec)……….27 NW   @   07:53 A.M.
VECTOR #2 (1-Sec)……….29 WNW  @   11:30 A.M.
DAVIS #1……………….25 W    @   09:40 A.M.
DAVIS #2 ………………23 WNW  @   09:43 A.M.
RMY #1 (Instantaneous)…..28 NW   @   09:48 A.M.
RMY #2 (Instantaneous)…..28 WNW  @   11:30 A.M.
MERLIN…………………26 NW
RICHARDS (C5C) (Inst)……26 NW   @   09:48 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………18 WNW  @   11:32 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..18 NW   @   09:49 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..20 WNW  @   11:32 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………19 WNW  @   11:32 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………18 WNW  @   09:45 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..19 NW   @   09:49 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..19 WNW  @   11:32 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………19 NW   @   09:49 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………9.7 WNW [233 total miles] VECTOR #1……………….9.8
VECTOR #2………………10.4
DAVIS #1………………..9.9 WNW
DAVIS #2………………….M
RMY #1………………….9.7 WNW
RMY #2…………………10.1 WNW
RICHARDS (C5C)………….10.1

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.11
TOTAL PRECIPITATION FOR THE MONTH (JUL)……..2.22 DEPARTURE…..+0.32
TOTAL PRECIPITATION FOR THE YEAR (2026)…….20.88 DEPARTURE…..-8.25

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PRELIMINARY CLIMATE SUMMARY FOR JULY 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

7/1  95/68/82/+11/0.00/704/77            23 WSW VEC1 23 SW  RMY 24
7/2  99/72/86/+15/0.04/822/90            40 W   VEC1 39 W   RMY 45 TSTM
7/3  98/77/88/+16/0.00/803/88            32 WNW VEC1 32 WNW RMY 34 TSTM
7/4  94/73/84/+12/0.01/765/84            29 WNW VEC1 29 WNW RMY 29
7/5  83/69/76/+4/T/355/39                20 SSE VEC1 20 SE  RMY 17
7/6  74/60/67/-5/0.05/009/01             24 E   VEC1 24 E   RMY 24
7/7  65/61/63/-9/2.11/000/00             40 ENE VEC1 39 NE  RMY 40
7/8  83/58/72/-1/0.01/780/86             26 N   VEC1 26 N   RMY 25
7/9  91/65/78/+5/0.00/834/92             29 SW  VEC1 27 SW  RMY 29
7/10 88/69/79/+6/0.00/724/80             21 NE  VEC1 21 NE  RMY 23
7/11 82/66/74/+1/0.00/795/88             20 E   VEC1 20 E   RMY 19
7/12 81/61/71/-2/0.00/884/98             18 ENE VEC1 18 ENE RMY 18
7/13 86/62/74/+1/0.00/…/..             30 SW  VEC1 30 SSW RMY 32
7/14 88/67/78/+5/0.00/…/..             32 WSW VEC1 32 WSW RMY 34
7/15 82/67/75/+2/0.00/…/..             33 WNW VEC1 33 WNW RMY 33
7/16 86/63/75/+2/0.00/…/..             33 W   VEC1 34 NNW RMY 33
7/17 83/61/72/-1/0.00/…/..             28 NW  VEC1 27 NW  RMY 28

7/18 The low since midnight is 65F, the daily normal low is 64F.

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JULY DAILY RECORDS TO DATE

7/2 RECORD HIGH MAXIMUM TEMPERATURE OF 99F,
BEATING THE PREVIOUS RECORD OF 95F SET IN 1963

7/2 RECORD HIGH MINIMUM TEMPERATURE OF 72F,
THIS TIED THE RECORD WITH 1901, 1913, AND 1963

7/3 RECORD HIGH MINIMUM TEMPERATURE OF 77F,
BEATING THE PREVIOUS RECORD OF 76F SET IN 2002

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

RECORDS FOR JULY 18
HIGH 96F IN 1991, 1999
LOW 54F IN 1892, 1956, 1971
PRECIP 1.65 INS IN 2000
WIND 43e MPH SW IN 1949

RECORDS FOR JULY 19
HIGH 96F IN 1977, 1991
LOW 50F IN 1890
PRECIP 1.10 INS IN 1951
WIND 63 MPH SSW IN 1982

TODAY’S REPORT PREPARED BY: Matt Douglas