Saturday, April 5, 2025

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

SATURDAY, APRIL 5, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0519E
SUNSET:  1815E

CHILLY AS RAIN MOVES IN FOR THE AFTERNOON….

Today has featured overcast skies, thanks to a mid-level cloud deck
advancing in from the west. There were a few breaks in the clouds off
to the east around sunrise, but otherwise the sky has remained gray.
Rain began here around 11am. The intensity has been very light thus far
due to the air at the surface not being fully saturated.

In typical springtime fashion, we find ourselves on a bit of a temperature
roller coaster, with temperatures today running 15-25 degrees below those at the
same time yesterday. We have remained in the 40s all day, with the high
of 47F occurring right at midnight. As aforementioned, the dew point has
lagged behind the temperature quite a bit. It held in the low 30s through
much of the morning before rising to the upper 30s following the onset of
the precipitation.

The wind remains on the lighter side, with flow now out of the southeast.
The average speed so far is 10mph, with a peak gust to 23mph just before 7am.

Visibility was excellent this morning, with views extending up to 70 miles.
As the rain has moved in from the west, the visibility has dropped to 20 miles.

The maximum temperature for today is 47F degrees, which is 5 degrees
below the normal high of 52F. The minimum temperature since midnight
is 41F degrees, which is 7 degrees above the normal low of 34F.

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Today’s Observations:

7 A.M.
Weather: Overcast altostratus/altocumulus, few breaks in overcast distant NE-S,
higher clouds visible NE-S
Temperature: 42F; Dew Point: 32F; Relative Humidity: 68%
Wind: E @ 9G15 kts
Sea-level pressure: 1030.3 mb; 30.42 in. Hg: rising, then more rapidly
Visibility: 70 miles
6-hr Max temp: 45F
6-hr Min temp: 42F
24-hr Precip:  0.00 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 E120 OVC 70 303/42/32/1009G15/042/ FEW BINOVC DSNT NE-S
HIER CLDS VSBL NE-S/ 8/07/ 53009 10045 20042

10 A.M.
Weather: Overcast altocumulus/altostratus, few stratocumulus distant NW-NE-SE
Temperature: 43F; Dew Point: 32F; Relative Humidity: 65%
Wind: SE @ 11G17 kts
Sea-level pressure: 1029.9 mb; 30.41 in. Hg: rising, then falling
Visibility: 60 miles
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E95 OVC 60 299/43/32/1311G17/041/ FEW SC DSNT NW-NE-SE/ 8/57/ 58004

1 P.M.
Weather: Overcast nimbostratus, light rain,
few lower stratus fractus all quadrants
Temperature: 42F Dew Point: 38F; Relative Humidity: 85%
Wind: SE @ 5 kts, wind light
Sea-level pressure: 1026.8 mb; 30.32 in. Hg: falling unsteadily
Visibility: 20 miles, thin fog all quadrants
6-hr Max temp: 44F
6-hr Min temp: 41F
6-hr Precip:  Trace
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E65 OVC 20R- 268/42/38/1405/032/ FEW LWR STFRA ALQDS THN F ALQDS
WND LGT/ 8/72/ 57031 6000/ 10044 20041

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SUMMARY FOR FRIDAY, APRIL 4, 2025

TEMPERATURE (DEGREES F)
MAX…….69   NORMAL…..51
MIN…….47   NORMAL…..33
MEAN……58   NORMAL…..42

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL………….+16
TOTAL DEPARTURE FOR THE MONTH…………………….+18 [+4.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY……………..7  DEPARTURE…….-16
TOTAL HEATING UNITS FOR THE MONTH…………….76  DEPARTURE…….-18
TOTAL HEATING UNITS FOR THE SEASON………….5005  DEPARTURE……-436
TOTAL HEATING UNITS LAST SEASON TO DATE……..4740  DEPARTURE……+265

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)………..31 NW   @   12:53 P.M.
VECTOR #1 (1-Sec)……….31 NW   @   12:53 P.M.
VECTOR #2 (1-Sec)……….30 NW   @   03:07 P.M.
DAVIS #1……………….29 WNW  @   12:52 P.M.
DAVIS #2 ………………28 W    @   10:51 A.M.
RMY #1 (Instantaneous)…..30 NW   @   12:53 P.M.
RMY #2 (Instantaneous)…..31 NW   @   03:07 P.M.
MERLIN…………………28 NW
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………20 NW   @   01:11 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..21      @   12:55 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..21      @   01:11 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………22 NW   @   12:55 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………20 WNW  @   10:53 A.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..21 NW   @   12:55 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..20 NW   @   01:11 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..11.5 WNW [277 total miles] VECTOR #1………………11.5
VECTOR #2………………12.1
DAVIS #1……………….11.8 NW
DAVIS #2……………….11.9 NW
RMY #1…………………11.1 NW
RMY #2…………………11.9 WNW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.17
TOTAL PRECIPITATION FOR THE MONTH…………..0.59 DEPARTURE…..-0.08
TOTAL PRECIPITATION FOR THE YEAR (2025)…….11.30 DEPARTURE…..-3.39

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE……-0.2
TOTAL SNOWFALL FOR THE MONTH………………TRACE DEPARTURE……-0.8
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……34.1 DEPARTURE…..-33.6

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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    55/32/44/+3/0.17/0.0/512/67       38 NW  VEC1 38 NW  RMY 40
4/2    42/27/35/-6/0.11/T/584/76         29 NNW VEC1 28 NNW RMY 29
4/3    62/32/47/+5/0.31/0.0/…/..       38 SW  VEC1 38 SW  RMY 39
4/4    69/47/58/+16/0.00/0.0/…/..      31 NW  VEC1 31 NW  RMY 30

4/5 The low since midnight is 41F, the daily normal low is 34F.

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APRIL DAILY RECORDS TO DATE

NONE.

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

RECORDS FOR APRIL 5
HIGH 81 IN 1928
LOW 15 IN 1995
PRECIP 2.15 IN. IN 1987
SNOWFALL 4.0 IN. IN 1898
PEAK GUST 76 MPH WNW IN 1963

RECORDS FOR APRIL 6
HIGH 82 IN 1921
LOW 16 IN 1982
PRE 1.72 INS IN 1886
SNOW 12.3 INS IN 1982
WIND 71e MPH WNW IN 1940

TODAY’S REPORT PREPARED BY: Joshua Polen