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Saturday, April 18, 2026

April 18, 2026

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SATURDAY, APRIL 18, 2026 ALL TIMES ARE…

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

SATURDAY, APRIL 18, 2026
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0458E
SUNSET:  1829E

CHILLY WITH DENSE FOG THROUGH THE MORNING LIFTING TO OVERCAST SKIES….

The day started with the summit in the clouds along with periods
of drizzle through the morning hours. By noon-time, the fog was
lifting and the drizzle finally came to end. Skies however have
remained cloudy with a chilly breeze coming in off the ocean.

Temperatures actually were gradually dropping through the morning,
from the upper 40s early in the morning to the mid 40s by late
morning where it remains into early this afternoon. Dew point
values have been in the 40s all day as well as one would expect.

Winds have been fairly steady through the day out of an easterly
direction. The average speed for the day so far is around 11mph.
The peak gust for the day so far is 26mph, which occurred just
before 8am this morning.

Visibility has been limited all day, but improving as we push
through the early afternoon hours. During the morning the view
was limited to 1/16th to 1/8th of a mile, but has reached upward
to 20-25 miles by early this afternoon with lingering thin fog.

The maximum temperature so far today is 48F degrees, which is
10 degrees below the normal high of 58F. The minimum temperature
since midnight is 44F degrees, which is 5 degrees above the
normal low of 39F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 200ft, light drizzle
Temperature: 47F; Dew Point: 47F; Relative Humidity: 100%
Wind: E @ 13G22 kts
Sea-level pressure: 1020.9 mb; 30.15 in. Hg: rising, then falling
Visibility: 1/16 mile, fog
6-hr Max temp: 48F
6-hr Min temp: 46F
24-hr Precip: 0.07 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 X W2 1/16L-F 209/47/47/0813G22/015/ 8//// 50015
6002/ 70007 10048 20046

10 A.M.
Weather: Sky obscured, vertical visibility 200ft, very light drizzle
Temperature: 46F; Dew Point: 46F; Relative Humidity: 100%
Wind: ENE @ 12G20 kts
Sea-level pressure: 1022.1 mb; 30.18 in. Hg: rising, then more slowly
Visibility: 1/8 mile, fog
3-hr Precip: 0.01 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 X W2 1/8L-F 221/46/46/0712G20/018/ PCPN VRY LGT/
8//// 51012 6001/

1 P.M.
Weather: Overcast stratus, few breaks in overcast distant N-NE
Temperature: 46F; Dew Point: 43F; Relative Humidity: 89%
Wind: ENE @ 9G16 kts
Sea-level pressure: 1020.9 mb; 30.15 in. Hg: falling, then more rapidly
Visibility: 25 miles, thin fog
6-hr Max temp: 46F
6-hr Min temp: 44F
6-hr Precip: 0.01 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E12 OVC 25 209/46/43/0709G16/015/ FEW BINOVC DSNT N-NE
THN F ALQDS/ 8/6// 58012 6001/ 10046 20044

————————————————————–

SUMMARY FOR FRIDAY, APRIL 17, 2026

TEMPERATURE (DEGREES F)
MAX…….62   NORMAL…..57
MIN…….47   NORMAL…..39
MEAN……55   NORMAL…..48

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………….+7
TOTAL DEPARTURE FOR THE MONTH………………………+84 [+4.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2025 THRU JUN 2026)
TOTAL HEATING UNITS FOR YESTERDAY…………….10  DEPARTURE…….+10
TOTAL HEATING UNITS FOR THE MONTH (MAR)………272  DEPARTURE…….-80
TOTAL HEATING UNITS FOR THE SEASON………….5590  DEPARTURE……-109
TOTAL HEATING UNITS LAST SEASON TO DATE……..5308  DEPARTURE……+282

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)………..31 NE   @   12:36 P.M.
VECTOR #1 (1-Sec)……….32 NNW  @   12:00 A.M.
VECTOR #2 (1-Sec)……….31 NNW  @   12:00 A.M.
DAVIS #1……………….29 NNW  @   12:00 A.M.
DAVIS #2 ………………28 NE   @   12:36 P.M.
RMY #1 (Instantaneous)…..31 NE   @   12:36 P.M.
RMY #2 (Instantaneous)…..31 NNW  @   12:00 A.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)……30 NNW  @   12:00 A.M.

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………26 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..25 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..24 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………25 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………25 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..25 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..24 NNW  @   12:00 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE………24 NNW  @   12:00 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.4 ENE [177 total miles] VECTOR #1……………….7.8
VECTOR #2……………….8.1
DAVIS #1………………..7.9 ENE
DAVIS #2………………….M
RMY #1………………….7.9 ENE
RMY #2………………….8.0 NE
RICHARDS (C5C)…………..8.2

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.07 DEPARTURE…..-0.08
TOTAL PRECIPITATION FOR THE MONTH (APR)……..1.62 DEPARTURE…..-1.26
TOTAL PRECIPITATION FOR THE YEAR (2026)…….13.29 DEPARTURE…..-3.61

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE…..-0.1
TOTAL SNOWFALL FOR THE MONTH (APR)…………TRACE DEPARTURE…..-2.4
TOTAL SNOWFALL FOR THE SEASON (2025-2026)……81.6 DEPARTURE….+12.3

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR APRIL CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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

4/1  73/38/56/+15/0.16/0.0/061/08        35 NE  VEC1 34 ENE RMY 35
4/2  38/34/36/-5/0.45/0.0/000/00         31 E   VEC1 31 E   RMY 33
4/3  67/35/51/+9/0.04/0.0/270/35         31 SW  VEC1 31 SW  RMY 35
4/4  58/35/47/+5/0.01/0.0/093/12         39 ENE VEC1 38 ENE RMY 42
4/5  55/36/46/+3/0.16/0.0/008/01         35 NW  VEC1 36 NW  RMY 38
4/6  50/32/41/-2/0.00/0.0/708/91         46 WNW VEC1 46 WNW RMY 47
4/7  50/29/40/-4/0.10/T/336/43           39 WNW VEC1 39 WNW RMY 41
4/8  43/25/34/-10/0.00/0.0/753/96        30 NNW VEC1 31 NNW RMY 32
4/9  56/30/43/-1/0.00/0.0/755/96         35 S   VEC1 35 SSW RMY 35
4/10 67/33/50/+5/0.00/0.0/672/85         37 S   VEC1 36 SSW RMY 37
4/11 60/41/51/+6/0.00/0.0/690/87         37 NW  VEC1 37 NW  RMY 37
4/12 54/35/45/-1/0.02/0.0/549/69         28 S   VEC1 28 S   RMY 28
4/13 69/41/55/+9/T/0.0/168/21            40 SSW VEC1 41 SSW RMY 42
4/14 83/58/71/+24/0.15/0.0/617/77        46 SSW VEC1 46 SSW RMY 47
4/15 77/44/61/+14/T/0.0/626/78           25 NE  VEC1 25 NE  RMY 24
4/16 69/45/57/+10/0.37/0.0/…/..        45 NW  VEC1 44 NW  RMY 50
4/17 62/47/55/+7/0.14/0.0/…/..         31 NE  VEC1 32 NNW RMY 31

4/18 The low since midnight is 44F, the daily normal low is 39F.

————————————————————–

APRIL DAILY RECORDS TO DATE

NONE.

————————————————————–

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

RECORDS FOR APRIL 18
HIGH 92 IN 1976
LOW 23 1887
PRECIP 1.48 IN 1954
SNOWFALL 4.3 IN. IN 2020
PEAK GUST 59 MPH S IN 1982

RECORDS FOR APRIL 19
HIGH 94 IN 1976 [RECORD FOR MONTH] LOW 21 IN 1890
PRECIP 1.71 IN 1969
SNOWFALL 1.3 IN. IN 1967
PEAK GUST 66 MPH E IN 1984

TODAY’S REPORT PREPARED BY: Matt Douglas

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Please read the full Policy before accessing Observatory data · Effective January 1, 2025

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Effective January 1, 2025 · Milton, Massachusetts · bluehill.org
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