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Friday, March 21, 2025

March 21, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA FRIDAY, MARCH 21, 2025 ALL TIMES ARE…

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

FRIDAY, MARCH 21, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0545E
SUNSET:  1758E

EARLY MORNING RAIN MOVES OUT, REPLACED WITH GUSTY WINDS AND
COOLER TEMPERATURES….

Today is the first day of the spring equinox and we celebrated
with a chilly, wet, and raw morning. From last night and up to
this afternoon, we received 0.37 inches of rain which puts us
in the green for the month, although we are still in a deficit
for the season. The rain moved out by mid morning and was replaced
by gusty winds. Although we remained dry, clouds lingered above
which prevented us from seeing any sunshine.

Temperatures held pretty steady today, even though the wind has
given us wind chill values well below seasonable. We started this
morning around 43F and our last observation we were at 41F. With
the rain moving through in the morning hours, our low for the day
so far occurred in the 8am hour with a temperature of 39F.

As mentioned, the wind has made a comeback with the passing of the
rain. Winds overnight were in a southerly and southeasterly flow
but changed to a northwesterly flow just after 6am EST. With the
wind shift came gustier winds which have persisted throughout the
day. The average speed is around 14mph for the day and our peak gust
so far today is 48mph, occurring just after our final observation.
We have had frequent gusts into the 30’s for much of the late morning
and early afternoon.

Visibility was poor this morning, with an average of about 15 miles
due to rain and fog. After the rain moved out of the area, we were
able to improve to 60 miles for much of the day.

The maximum temperature for today is 46F degrees, which is one degree
above the normal high of 45F. The minimum temperature since midnight is
39F degrees, which is 11 degrees above the normal low of 28F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Light rain showers, overcast stratus, precipitation very light
Temperature: 43F; Dew Point: 43F; Relative Humidity: 100%
Wind: NW @ 16G24 kts, peak wind NW 33mph at 06:53 A.M.
Sea-level pressure: 994.9 mb; 29.38 in. Hg: rising unsteadily
Visibility: 15 miles, 10 miles N-NE, 20 miles ENE-S-W-NNW, thin fog
all quadrants
6-hr Max temp: 46F
6-hr Min temp: 43F
24-hr Precip:  0.26 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 E8 OVC 15R- 949/43/43/3216G24/938/ THN F ALQDS VSBY 10 N-NE
20 ENE-S-W-NNW PCPN VRY LGT PK WND 3229/53/ 8/6// 52014 6023/ 70026
10046 20043

10 A.M.
Weather: Overcast stratus
Temperature: 42F; Dew Point: 36F; Relative Humidity: 78%
Wind: NW @ 20G28 kts, peak wind NW 40mph at 09:54 A.M.
Sea-level pressure: 995.9 mb; 29.41 in. Hg: rising, then more slowly
Visibility: 60 miles
3-hr Precip:  0.11 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E15 OVC 60 959/42/36/3220G28/941/ PK WND 3235/54/ 8/6//
51010 6011/

1 P.M.
Weather: Overcast stratocumulus
Temperature: 41F; Dew Point: 30F; Relative Humidity: 65%
Wind: NW @ 20G30 kts, peak wind NW 42mph at 12:12 P.M.
Sea-level pressure: 997.3 mb; 29.45 in. Hg: falling, then rising
Visibility: 60 miles
6-hr Max temp: 45F
6-hr Min temp: 39F
6-hr Precip:  0.11 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E45 OVC 60 973/41/30/3020G30/945/ PK WND 3136/12/ 8/5// 53014
6011/ 10045 20039

————————————————————–

SUMMARY FOR THURSDAY, MARCH 20, 2025

TEMPERATURE (DEGREES F)
MAX…….55   NORMAL…..45
MIN…….36   NORMAL…..28
MEAN……46   NORMAL…..37

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………..+9
TOTAL DEPARTURE FOR THE MONTH……………………+132 [+6.4 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)………..30 S    @   03:44 P.M.
VECTOR #1 (1-Sec)……….30 S    @   03:44 P.M.
VECTOR #2 (1-Sec)……….30 S    @   03:45 P.M.
DAVIS #1……………….29 S    @   04:47 P.M.
DAVIS #2 ………………37 S    @   04:42 P.M.
RMY #1 (Instantaneous)…..30 S    @   03:44 P.M.
RMY #2 (Instantaneous)…..30 S    @   03:45 P.M.
MERLIN…………………33 NW
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………20 S    @   04:42 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..20      @   04:42 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..21      @   03:46 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………20 S    @   04:49 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………24 S    @   04:42 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..20 S    @   04:42 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..21 SSE  @   03:46 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL………7.7 S  [185 total miles] VECTOR #1……………….8.0
VECTOR #2……………….8.4
DAVIS #1………………..7.5 SSE
DAVIS #2………………..7.7 SSE
RMY #1………………….7.8 SE
RMY #2………………….8.4 SE
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.26 DEPARTURE…..+0.07
TOTAL PRECIPITATION FOR THE MONTH…………..3.63 DEPARTURE…..+0.09
TOTAL PRECIPITATION FOR THE YEAR (2025)……..9.28 DEPARTURE…..-2.76

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…..-11.3
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……34.1 DEPARTURE…..-29.1

————————————————————–

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   55/36/46/+9/0.03/0.0/…/..       30 S   VEC1 30 S   RMY 30

3/21 The low since midnight is 39F, 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 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

RECORDS FOR MARCH 22
HIGH 81 IN 2012
LOW 3 IN 1885
PRE 3.48 INS. IN 2001
SNOW 8.7 INS. 1967
WIND 84e MPH E IN 1977

TODAY’S REPORT PREPARED BY: Amanda Joly

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