Thursday, May 22, 2025

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

THURSDAY, MAY 22, 2025
ALL TIMES ARE IN EASTERN STANDARD TIME (EST)
SUNRISE: 0416E
SUNSET: 1906E

LATE SEASON NOR’EASTER BRINGS RAIN AND GUSTY WINDS TO THE AREA….

The calendar says May, but Mother Nature says March! Rain began
falling very early this morning and has continued into early this
afternoon. The rain has come down moderately at times. 0.08″ was
measured through 7am with an additional 0.44″ being recorded by
1pm. In addition to the rainfall, an easterly wind has been
gradually increasing bringing very raw and chilly air to into the
region.

Temperatures are well below normal for the day once again, at least
in terms of the maximum temperature. Values have been stuck in the
mid 40s all day. As a matter of fact, we’ve only seen 2 degrees of
spread between the max/min so far for the day, 45F/43F respectively.
This is again solidly 20+ degrees below expected values for the
date. With the saturated air and windswept rain, it definitely
feels miserable outdoors. This is a great day for soup/stew or a
hot beverage!

The easterly flow has been gradually increasing through the day,
but more so in the last couple of hours. The average speed for the
day so far is around 15mph. Gusts were frequently exceeding 25mph
during the morning, but values over 30mph have become much more
frequent early this afternoon. The peak gust so far for the day is
36mph, which occurred a couple of times between 11am and 1pm.

Visibility has been gradually decreasing as one would expect as the
rain intensity has increased. The view was 10-15 miles early this
morning, but has dropped to under 5 miles by early this afternoon.

The maximum temperature for today is 45F degrees, which is 23 degrees
below the normal high of 68F. The minimum temperature since midnight
is 43F degrees, which is 7 degrees below the normal low of 50F.

————————————————————–

Today’s Observations:

7 A.M.
Weather: Broken stratocumulus, overcast nimbostratus, light rain,
few lower stratus fractus all quadrants
Temperature: 44F; Dew Point: 44F; Relative Humidity: 99%
Wind: E @ 14G27 kts, peak wind E 31mph at 6:45 A.M.
Sea-level pressure: 1015.7 mb; 29.99 in. Hg: falling, then rising
Visibility: 10 miles, thin fog
6-hr Max temp: 44F
6-hr Min temp: 44F
24-hr Precip: 0.08 inches
24-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1155 E10 BKN 20 OVC 10R- 157/44/44/1014G27/999/ FEW LWR STFRA
ALQDS THN F ALQDS PK WND 1027/45/ 8/52/ 55001 6008/ 70008 10044 20044

10 A.M.
Weather: Broken stratocumulus, overcast nimbostratus, light rain,
few lower stratus fractus all quadrants
Temperature: 44F; Dew Point: 44F; Relative Humidity: 100%
Wind: E @ 14G23 kts, peak wind E 31mph at 9:26 A.M.
Sea-level pressure: 1015.2 mb; 29.98 in. Hg: falling, then steady
Visibility: 5 miles, fog
3-hr Precip: 0.13 inches
3-hr Snowfall: 0.0 inches
BHO SA 1455 E9 BKN 20 OVC 5R-F 152/44/44/0914G23/998/ FEW LWR STFRA
ALQDS PK WND 0927/26/ 8/52/ 56005 6013/

1 P.M.
Weather: Broken stratus fractus, overcast stratus, light rain,
stratus fractus drifting over summit
Temperature: 44F Dew Point: 44F; Relative Humidity: 100%
Wind: ENE @ 15G27 kts, peak wind ENE 36mph at 12:15 P.M.
Sea-level pressure: 1013.0 mb; 29.91 in. Hg: falling, then more slowly
Visibility: 4 miles, fog
6-hr Max temp: 45F
6-hr Min temp: 43F
6-hr Precip: 0.44 inches
6-hr Snowfall: 0.0 inches
Snow Depth: 0 inches
BHO SA 1755 E5 BKN 13 OVC 4R-F 130/44/44/0715G27/991/
STFRA DRFTG OVR SMT PK WND 0731/15/ 8/7// 56022 6044/ 10045 20043

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SUMMARY FOR WEDNESDAY, MAY 21, 2025

TEMPERATURE (DEGREES F)
MAX…….48 NORMAL…..68
MIN…….43 NORMAL…..50
MEAN……46 NORMAL…..59

DEPARTURE FROM 30-YEAR (1991-2020) NORMAL……………-13
TOTAL DEPARTURE FOR THE MONTH………………………+59 [+2.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON: JUL 2024 THRU JUN 2025)
TOTAL HEATING UNITS FOR YESTERDAY…………….19 DEPARTURE…….+12
TOTAL HEATING UNITS FOR THE MONTH……………136 DEPARTURE…….-61
TOTAL HEATING UNITS FOR THE SEASON………….5534 DEPARTURE……-550
TOTAL HEATING UNITS LAST SEASON TO DATE……..5365 DEPARTURE……+169

COOLING DEGREE DAYS (SEASON JAN 2025 THRU DEC 2025)
TOTAL COOLING UNITS FOR YESTERDAY……………..0 DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH…………….11 DEPARTURE………0
TOTAL COOLING UNITS FOR THE SEASON……………14 DEPARTURE………0
TOTAL COOLING UNITS LAST SEASON TO DATE………..2 DEPARTURE…….+12

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)………..28 E @ 10:24 P.M.
VECTOR #1 (1-Sec)……….28 E @ 10:24 P.M.
VECTOR #2 (1-Sec)……….27 ENE @ 12:25 P.M.
DAVIS #1……………….27 ESE @ 10:24 P.M.
DAVIS #2 ………………26 E @ 12:25 P.M.
RMY #1 (Instantaneous)…..27 E @ 12:25 P.M.
RMY #2 (Instantaneous)…..27 E @ 10:24 P.M.
MERLIN………………….M
RICHARDS (C5C) (Inst)…..OTS

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………16 E @ 10:28 P.M.
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE…………..18 @ 10:24 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..17 @ 10:38 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………19 E @ 10:24 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………18 E @ 10:24 P.M.
MAXIMUM 2-MINUTE RMY #1 AVERAGE……………..18 E @ 10:24 P.M.
MAXIMUM 2-MINUTE RMY #2 AVERAGE……………..17 E @ 10:24 P.M.
MAXIMUM 2-MINUTE RICHARDS (C5C) AVERAGE……..OTS

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……..10.3 E [247 total miles] VECTOR #1……………….9.8
VECTOR #2………………10.5
DAVIS #1……………….10.9 E
DAVIS #2……………….10.7 E
RMY #1…………………10.1 ENE
RMY #2…………………10.3 ENE
RICHARDS (C5C)…………..OTS

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……..0.08 DEPARTURE…..-0.04
TOTAL PRECIPITATION FOR THE MONTH…………..3.43 DEPARTURE…..+0.93
TOTAL PRECIPITATION FOR THE YEAR (2025)…….17.55 DEPARTURE…..-3.73

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

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PRELIMINARY CLIMATE SUMMARY FOR MAY 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

5/1 69/43/56/+3/0.00/0.0/744/88 28 S VEC1 28 SSW RMY 28
5/2 79/47/63/+9/0.19/0.0/339/40 28 SE VEC1 29 SE RMY 25 TSTM
5/3 84/54/69/+15/0.15/0.0/561/66 43 SSW VEC1 42 SSW RMY 44 TSTM
5/4 77/50/64/+10/0.06/0.0/256/30 33 SW VEC1 34 SW RMY 32
5/5 50/46/48/-7/0.26/0.0/000/00 35 ENE VEC1 35 ENE RMY 36
5/6 61/48/55/0/0.57/0.0/000/00 26 S VEC1 27 ENE RMY 27
5/7 72/54/63/+8/0.01/0.0/310/36 33 SSW VEC1 33 SW RMY 35
5/8 74/51/63/+8/0.04/0.0/474/55 18 ESE VEC1 18 ESE RMY 18
5/9 51/46/49/-7/1.15/0.0/000/00 33 E VEC1 34 ENE RMY 35
5/10 62/45/54/-2/0.29/0.0/121/14 36 NW VEC1 37 NW RMY 41
5/11 70/49/60/+4/0.00/0.0/851/98 33 NW VEC1 32 NW RMY 34
5/12 73/46/60/+3/0.00/0.0/853/98 36 SW VEC1 34 SW RMY 36
5/13 70/51/61/+4/0.00/0.0/759/87 26 ESE VEC1 27 ESE RMY 26
5/14 73/48/61/+4/0.00/0.0/586/67 18 SSE VEC1 19 SSE RMY 17
5/15 72/58/65/+8/0.62/0.0/079/09 20 SSE VEC1 20 SSE RMY 19 TSTM
5/16 78/61/70/+12/0.00/0.0/404/46 23 SW VEC1 23 SSW RMY 23
5/17 76/58/67/+9/T/0.0/264/30 30 S VEC1 29 S RMY 30
5/18 68/54/61/+3/T/0.0/512/58 39 W VEC1 39 W RMY 38
5/19 63/46/55/-3/0.00/0.0/371/42 41 NW VEC1 42 NW RMY 44
5/20 55/45/50/-9/T/0.0/000/00 29 NNW VEC1 29 NNW RMY 30
5/21 48/43/46/-13/0.01/0.0/009/01 28 E VEC1 28 E RMY 27