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Thursday, March 20, 2025

March 20, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA THURSDAY, MARCH 20, 2025 ALL TIMES ARE…

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

THURSDAY, MARCH 20, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0547E
SUNSET:  1757E

DRIZZLE AND FOG THIS MORNING DISSIPATE, BUT OVERCAST SKIES REMAIN….

We started the day with areas of drizzle and dense fog here on the
summit. The drizzle came down enough to be measured early this
morning with 0.02″ being recorded. The drizzle came to an end
prior to the 7am observation, but the fog lingered until the late
morning hours before finally lifting. Overcast skies however
remain into early this afternoon with only some brightening of
the sky appearing from time to time.

Temperatures are warming at least from the morning low in the mid
30s to the low 50s by early this afternoon, despite not seeing
any sunshine. The air is quite moist as one would expect as the
dew point has also been rising from the 30s into the mid to upper
40s.

Today has been the lightest wind day of the month so far with an
easterly wind gradually being southerly. The average speed however
has only been around 5mph for the day. The peak gust so far today
has only been 17mph, occurring just before the 1pm observation.

Visibility has been gradually improving from the morning values
of a 1/4 mile or less, to around 20-25 miles early this afternoon
outside of pockets of drizzle.

The maximum temperature for today is 52F degrees, which is 7 degrees
above the normal high of 45F. The minimum temperature since midnight
is 36F degrees, which is 8 degrees above the normal low of 28F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Sky obscured, vertical visibility 200ft
Temperature: 39F; Dew Point: 39F; Relative Humidity: 100%
Wind: E @ 3 kts, wind light
Sea-level pressure: 1015.9 mb; 29.98 in. Hg: falling, then rising
Visibility: 1/4 mile, fog
6-hr Max temp: 39F
6-hr Min temp: 36F
24-hr Precip:  0.02 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 X W2 1/4F 152/39/39/0903/998/ L-B09E22 WND LGT/ 8////
55005 6002/ 70002 10039 20036

10 A.M.
Weather: Sky obscured, vertical visibility 300ft
Temperature: 44F; Dew Point: 44F; Relative Humidity: 100%
Wind: SE @ 3 kts, wind light and variable
Sea-level pressure: 1013.5 mb; 29.93 in. Hg: falling, then more rapidly
Visibility: 1 mile, variable 3 miles, fog
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 X W3 1VF 135/44/44/1403/993/ VSBY 1V3 WND L/V/ 8//// 58017

1 P.M.
Weather: Overcast stratus, very light drizzle
Temperature: 52F; Dew Point: 48F; Relative Humidity: 87%
Wind: S @ 8G15 kts
Sea-level pressure: 1010.5 mb; 29.84 in. Hg: falling, then more slowly
Visibility: 25 miles, 5 miles SSW-SW, 10 N-NNE, 15 NE-ENE, thin fog
6-hr Max temp: 52F
6-hr Min temp: 39F
6-hr Precip:  Trace
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E8 OVC 25L- 105/52/48/1708G15/984/ THN F ALQDS L-B52
PCPN VRY LGT VSBY 5 SSW-SW 10 N-NNE 15 NE-ENE/ 8/6// 56030 6000/
10052 20039

————————————————————–

SUMMARY FOR WEDNESDAY, MARCH 19, 2025

TEMPERATURE (DEGREES F)
MAX…….52   NORMAL…..45
MIN…….34   NORMAL…..28
MEAN……43   NORMAL…..36

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..+7
TOTAL DEPARTURE FOR THE MONTH……………………+123 [+6.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….22  DEPARTURE……..-7
TOTAL HEATING UNITS FOR THE MONTH……………472  DEPARTURE……-124
TOTAL HEATING UNITS FOR THE SEASON………….4653  DEPARTURE……-375
TOTAL HEATING UNITS LAST SEASON TO DATE……..4328  DEPARTURE……+325

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

F420C (Official)………..18 NE   @   09:22 A.M.
VECTOR #1 (1-Sec)……….18 NE   @   03:15 A.M.
VECTOR #2 (1-Sec)……….18 NNE  @   03:18 A.M.
DAVIS #1……………….17 ENE  @   09:22 A.M.
DAVIS #2 ………………17 NE   @   03:18 A.M.
RMY #1 (Instantaneous)…..17 NE   @   03:22 A.M.
RMY #2 (Instantaneous)…..18 NE   @   03:51 A.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………14 NE   @   03:57 A.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..13      @   06:14 A.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..13      @   03:23 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………13 ENE  @   03:57 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………13 ENE  @   04:13 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..13 NE   @   04:13 A.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..13 NE   @   04:13 A.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.8 NE [186 total miles] VECTOR #1……………….7.9
VECTOR #2……………….8.3
DAVIS #1………………..8.3 ENE
DAVIS #2………………..8.1 ENE
RMY #1………………….7.9 ENE
RMY #2………………….8.2 NE
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.02 DEPARTURE…..-0.17
TOTAL PRECIPITATION FOR THE MONTH…………..3.37 DEPARTURE…..+0.02
TOTAL PRECIPITATION FOR THE YEAR (2025)……..9.02 DEPARTURE…..-2.83

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……-0.5
TOTAL SNOWFALL FOR THE MONTH………………TRACE DEPARTURE…..-10.8
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……34.1 DEPARTURE…..-28.6

————————————————————–

PRELIMINARY CLIMATE SUMMARY FOR MARCH 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

3/1    50/21/36/+5/T/T/081/12            46 NW  VEC1 46 NW  RMY 49
3/2    28/14/21/-11/0.00/0.0/672/99      41 NW  VEC1 42 NW  RMY 43
3/3    31/8/20/-12/0.00/0.0/667/98       28 NW  VEC1 28 NW  RMY 31
3/4    48/23/36/+4/0.00/0.0/390/57       41 SW  VEC1 42 SW  RMY 43
3/5    54/41/48/+16/0.52/0.0/021/03      50 SSW VEC1 50 SSW RMY 55
3/6    55/32/44/+11/0.66/T/014/02        69 S   VEC1 69 S   RMY 68
3/7    41/25/33/0/T/T/638/92             60 WNW VEC1 61 WNW RMY 64
3/8    40/27/34/+1/0.00/0.0/619/89       55 W   VEC1 55 W   RMY 58
3/9    45/25/35/+2/0.00/0.0/544/78       40 W   VEC1 39 W   RMY 42
3/10   60/33/47/+13/0.00/0.0/680/97      38 WNW VEC1 38 WNW RMY 39
3/11   62/37/50/+16/0.00/0.0/676/96      39 SSW VEC1 40 SSW RMY 40
3/12   48/32/40/+6/T/T/544/77            29 N   VEC1 29 N   RMY 29
3/13   46/32/39/+5/0.00/0.0/483/68       25 ESE VEC1 26 ESE RMY 25
3/14   54/33/44/+9/0.00/0.0/570/80       22 SSW VEC1 22 SSW RMY 22
3/15   59/37/48/+13/0.00/0.0/358/50      28 S   VEC1 28 S   RMY 28
3/16   67/44/56/+21/0.05/0.0/136/19      56 SSW VEC1 58 SSW RMY 58
3/17   58/38/48/+12/2.12/0.0/000/00      60 SSW VEC1 60 SSW RMY 60
3/18   48/34/41/+5/0.00/0.0/362/50       31 NNW VEC1 31 NNW RMY 32
3/19   52/34/43/+7/0.00/0.0/662/91       18 NE  VEC1 18 NE  RMY 17

3/20 The low since midnight is 36F, the daily normal low is 28F.

————————————————————–

MARCH DAILY RECORDS TO DATE

3/16 RECORD HIGH MINIMUM TEMP OF 44F;
OLD RECORD WAS 43F IN 1921, 1973

3/17 RECORD PRECIPITATION AMOUNT OF 2.12 INS;
OLD RECORD WAS 1.97 INS IN 1968

————————————————————–

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

RECORDS FOR MARCH 20
HIGH 79 IN 1945
LOW 4 IN 1885
PRECIP 1.39 INS. IN 1957
SNOWFALL 11.4 INS. IN 1957
PEAK GUST 63 MPH SE IN 1975

RECORDS FOR MARCH 21
HIGH 81 IN 1921
LOW 2 IN 1885
PRECIP 2.67 INS. IN 1974
SNOWFALL 10.6 INS. IN 1958
PEAK GUST 72 MPH NE IN 1958

TODAY’S REPORT PREPARED BY: Matt Douglas

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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Effective January 1, 2025 · Blue Hill Observatory & Science Center · Milton, Massachusetts