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Wednesday, April 30, 2025

April 30, 2025

BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA WEDNESDAY, APRIL 30, 2025 ALL TIMES ARE…

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

WEDNESDAY, APRIL 30, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0440E
SUNSET:  1843E

EARLY MORNING CLOUDS GIVE WAY TO PLENTY OF SUNSHINE….

A cold front passed through the area early this morning. With the
lack of any rain with it, the only noticeable feature with this
frontal passage was the decent cold air advection that took place
during the morning hours. Associated with the cold air advection
were gusty winds and a period of falling temperatures.

Temperatures were warm during the overnight period, only dropping
to 59F for a time around 3am, before rising again into the low 60s
just ahead of the front. Once the front passed, temperatures dropped
again to 59F around 8am. The record high minimum for today is 58F
set in 1903, however readings should drop below this before midnight
tonight, so we will likely not set a new record today.

Readings have recovered nicely early this afternoon into the low 70s
with dew point values dropping into the low 30s.

As mentioned, the wind picked up markedly following the frontal
passage and remained gusty throughout the day. The strongest of
the wind was during the morning hours, as the overall speed has
been gradually decreasing early this afternoon. The average speed
for the day so far is around 16mph, first out of the southwest
before the front, and then northwest thereafter. The peak gust for
the day is 36mph, which occurred at 9:28am this morning.

Visibility has been excellent all day, holding at around 70 miles,
despite a bit of haziness due to the high pollen count.

The maximum temperature for today is 72F degrees, which is 9 degrees
above the normal high of 63F. The minimum temperature since midnight
is 59F degrees, which is 16 degrees above the normal low of 43F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Broken altocumulus, broken cirrostratus, broken cirrus,
few stratocumulus distant W-N, virga all quadrants
Temperature: 61F; Dew Point: 43F; Relative Humidity: 50%
Wind: WNW @ 18G27 kts, peak wind W 33mph at 6:20 A.M.
Sea-level pressure: 1010.0 mb; 29.82 in. Hg: rising, then more rapidly
Visibility: 70 miles
6-hr Max temp: 62F
6-hr Min temp: 59F
24-hr Precip:  0.00 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 E150 BKN 180 BKN 250 BKN 70 100/61/43/2918G27/982/
FEW SC DSNT W-N VIRGA ALQDS PK WND 2829/20/ 8/558 53019 10062 20059

10 A.M.
Weather: Clear, few stratocumulus distant W-WNW, few altocumulus/
castellanus distant NE-SE-SSW, few cirrus distant S-WSW
Temperature: 66F; Dew Point: 43F; Relative Humidity: 43%
Wind: NW @ 16G29 kts, peak wind NW 36mph at 9:28 A.M.
Sea-level pressure: 1012.5 mb; 29.90 in. Hg: rising, then more rapidly
Visibility: 70 miles
3-hr Precip:  0.00 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 CLR 70 125/66/43/3216G29/990/ FEW SC DSNT W-WNW FEW AC/ACC
DSNT NE-SE-SSW FEW CI DSNT S-WSW PK WND 3231/28/ 8/581 53025

1 P.M.
Weather: Clear, few cirrus distant SE-SW-WNW
Temperature: 71F Dew Point: 33F; Relative Humidity: 25%
Wind: NW @ 14G27 kts, peak wind NNW 31mph at 12:50 P.M.
Sea-level pressure: 1013.2 mb; 29.92 in. Hg: steady, then rising
Visibility: 70 miles
6-hr Max temp: 71F
6-hr Min temp: 59F
6-hr Precip:  0.00 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 CLR 70 132/71/33/3214G27/992/ FEW CI DSNT SE-SW-WNW
PK WND 3327/50/ 8/001 53007 10071 20059

————————————————————–

SUMMARY FOR TUESDAY, APRIL 29, 2025

TEMPERATURE (DEGREES F)
MAX…….78   NORMAL…..62
MIN…….53   NORMAL…..43
MEAN……66   NORMAL…..53

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………+13
TOTAL DEPARTURE FOR THE MONTH………………………+60 [+1.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY……………..0  DEPARTURE…….-13
TOTAL HEATING UNITS FOR THE MONTH……………466  DEPARTURE…….-62
TOTAL HEATING UNITS FOR THE SEASON………….5395  DEPARTURE……-480
TOTAL HEATING UNITS LAST SEASON TO DATE……..5141  DEPARTURE……+251

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..1  DEPARTURE……..+1
TOTAL COOLING UNITS FOR THE MONTH……………..3  DEPARTURE………0
TOTAL COOLING UNITS FOR THE SEASON…………….3  DEPARTURE………0
TOTAL COOLING UNITS LAST SEASON TO DATE………..0  DEPARTURE……..+3

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)………..43 SSW  @   06:16 P.M.
VECTOR #1 (1-Sec)……….43 SSW  @   03:01 P.M.
VECTOR #2 (1-Sec)……….44 SSW  @   03:48 P.M.
DAVIS #1……………….45 S    @   02:56 P.M.
DAVIS #2 ………………47 S    @   03:25 P.M.
RMY #1 (Instantaneous)…..46 SSW  @   04:05 P.M.
RMY #2 (Instantaneous)…..46 SSW  @   03:48 P.M.
MERLIN…………………41 SSW
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………35 SSW  @   04:06 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..31      @   08:15 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..31      @   03:49 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………31 S    @   03:49 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………31 SSW  @   03:49 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..31 SSW  @   06:15 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..32 SSW  @   06:15 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..18.8 SW [452 total miles] VECTOR #1………………18.3
VECTOR #2………………19.2
DAVIS #1……………….18.1 SW
DAVIS #2……………….19.3 SW
RMY #1…………………18.1 SW
RMY #2…………………19.2 SW
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.00 DEPARTURE…..-0.14
TOTAL PRECIPITATION FOR THE MONTH…………..3.41 DEPARTURE…..-1.21
TOTAL PRECIPITATION FOR THE YEAR (2025)…….14.12 DEPARTURE…..-4.52

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…………..0.0 DEPARTURE…….0.0
TOTAL SNOWFALL FOR THE MONTH………………..1.7 DEPARTURE……-1.1
TOTAL SNOWFALL FOR THE SEASON (2024-2025)……35.8 DEPARTURE…..-33.9

————————————————————–

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/+5/0.31/0.0/000/00       38 SW  VEC1 38 SW  RMY 39
4/4    69/47/58/+16/0.00/0.0/456/59      31 NW  VEC1 31 NW  RMY 30
4/5    47/36/42/-1/0.49/0.0/000/00       25 ESE VEC1 29 SE  RMY 25
4/6    51/37/44/+1/0.20/0.0/016/02       22 NNW VEC1 21 NNW RMY 21
4/7    45/34/40/-4/0.18/T/000/00         24 E   VEC1 23 NNE RMY 23
4/8    40/26/33/-11/0.10/0.1/196/25      51 W   VEC1 48 W   RMY 51
4/9    46/24/35/-9/0.00/0.0/755/96       36 WNW VEC1 33 NW  RMY 36
4/10   49/29/39/-6/0.01/0.0/569/72       23 SSW VEC1 23 SSW RMY 25
4/11   45/31/38/-7/0.39/1.2/024/03       25 ENE VEC1 27 ENE RMY 26
4/12   36/33/35/-11/0.46/0.4/000/00      39 ENE VEC1 40 E   RMY 42
4/13   42/35/39/-7/0.16/0.0/000/00       38 NE  VEC1 38 NE  RMY 40
4/14   67/35/51/+4/0.00/0.0/745/93       29 WNW VEC1 29 NNW RMY 28
4/15   66/44/55/+8/0.04/0.0/209/26       53 NW  VEC1 51 NW  RMY 54 TSTM
4/16   51/37/44/-3/T/0.0/484/60          44 WNW VEC1 43 WNW RMY 47
4/17   59/35/47/-1/0.00/0.0/800/99       35 WNW VEC1 34 WNW RMY 34
4/18   66/38/54/+4/0.00/0.0/617/76       41 SSW VEC1 42 SSW RMY 43
4/19   82/52/67/+18/T/0.0/383/47         40 WNW VEC1 40 W   RMY 40
4/20   67/45/56/+7/0.00/0.0/768/94       53 NW  VEC1 54 NW  RMY 56
4/21   63/37/50/0/0.00/0.0/566/69        30 SSW VEC1 28 SSW RMY 31
4/22   75/44/60/+10/0.26/0.0/452/55      30 SSW VEC1 30 SSW RMY 30
4/23   72/43/58/+8/0.00/0.0/792/96       24 NW  VEC1 23 NW  RMY 26
4/24   74/45/60/+9/0.00/0.0/786/95       31 S   VEC1 31 S   RMY 30
4/25   78/52/65/+14/T/0.0/299/36         30 SSW VEC1 30 SSW RMY 30
4/26   59/49/54/+2/0.52/0.0/000/00       42 SSW VEC1 42 SSW RMY 43
4/27   56/41/49/-3/0.01/0.0/334/40       48 NW  VEC1 48 NW  RMY 56
4/28   74/43/59/+7/0.00/0.0/821/98       28 NW  VEC1 27 NW  RMY 27
4/29   78/53/66/+13/0.00/0.0/722/86      43 SSW VEC1 43 SSW RMY 46

4/29 The low since midnight is 53F, the daily normal low is 43F.

————————————————————–

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 30
HIGH 86 IN 1942
LOW 30 IN 1931
PRECIP 1.41 IN 1991
SNOWFALL 0.3 IN. IN 1909
PEAK GUST 64e MPH NW IN 1978

RECORDS FOR MAY 1
HIGH 87F IN 1899
LOW 29F IN 1978
PRECIP 2.53 INCHES IN 1921
SNOWFALL TRACE IN 1905,1917,1921,1995,2016
PEAK GUST 57 MPH NW IN 1974

TODAY’S REPORT PREPARED BY: MFD

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