Sunday, May 2, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
SUNDAY, MAY 2, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0438E
SUNSET: 1845E
BREEZY AND WARM WITH INTERMITTENT SUNSHINE
ATOP GREAT BLUE HILL….
We observed mostly cloudy conditions with intermittent
sunshine. Visibility was 65 miles on average, with a
max visibility of 70 miles being seen at the 7 A.M.
observation. Pressure has been steadily falling in
conjunction with an increase of cloud cover. Sky
cover is almost overcast at this point in time.
Wind has been a notable feature today, with a max
gust of 35 mph being seen so far. Wind speed is
above 20 mph with frequent gusts of almost 30 mph.
Despite mostly cloudy conditions and a cool westerly
wind, today is above normal in the temperature
department.
The high so far today is 73F, this is 11 degrees above the
normal high of 62F. The low since midnight is 48F, which
is 4 degrees above the daily normal low of 44F.
Today’s Observations:
7 A.M.
Weather: Scattered altocumulus, broken cirrostratus
Temperature: 53F; Dew Point: 36F; Relative Humidity: 51%
Wind: SSW at 15G23 kts
Sea-level pressure: 29.71 in Hg, falling unsteadily
Visibility: 70 miles
6-hr Max temp: 53F
6-hr Min temp: 48F
24-hr Precip: Trace
24-hr Snow: 0.0 ins.
Snow Depth: 0.0 ins.
BHO SA 1155 90 SCT 250 BKN 70 062/53/36/2115G23/971/ 8/056
56012 70000 10053 20048
10 A.M.
Weather: Scattered altostratus and broken cirrostratus
Temperature: 66F; Dew Point: 36F; Relative Humidity: 32%
Wind: WSW @ 12G18 kts
Sea-level pressure: 29.68 in Hg; rising then falling
Visibility: 65 miles
3-hr Precip: 0.0 ins.
3-hr Snow: 0.00 ins.
BHO SA 1455 180 SCT 250 BKN 65 052/66/36/2412G18/968/ 8/016
55010
1 P.M.
Weather: Scattered altostratus and cirrostratus
Temperature: 71F, Dew point: 41F; Relative Humidity: 33%
Wind: W @ 16G28 kts, peak of 34 mph W at 12:04 P.M.
Sea-level pressure: 29.63 in Hg; falling unsteadily
Visibility: 65 miles
6-hr Max temp: 73F
6-hr Min temp: 53F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 160 SCT 250 BKN 65 036/71/41/2816G28/963/ PK
WND 2729/04/ 8/076 56016 10073 20053
SUMMARY FOR SATURDAY, MAY 1, 2021
TEMPERATURE (DEGREES F)
MAX…….62 NORMAL…..62
MIN…….38 NORMAL…..43
MEAN……50 NORMAL…..53
DEPARTURE FROM 30-YEAR (1981-2010) NORMAL……..-3
TOTAL DEPARTURE FOR THE MONTH………………..-3 [-3.2 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………15 DEPARTURE…….+3
TOTAL HEATING UNITS FOR THE MONTH……………15 DEPARTURE…….+2
TOTAL HEATING UNITS FOR THE SEASON…………5356 DEPARTURE…..-691
TOTAL HEATING UNITS LAST SEASON TO DATE…….5528 DEPARTURE…..-172
PEAK WIND GUST (MPH):
420C/Official…………..31 WNW @ 1:02 P.M.
AEROVANE (south tower)…..35 WNW @ 1:19 P.M.
ASOS…………………..35 NW @ 9:11 A.M.
DAVIS #1……………….35 NW @ 1:18 P.M.
DAVIS #2 (south tower)…..34 WNW @ 8:50 A.M.
RMY……………………40 @ 9:09 A.M.
VECTOR…………………38 @ 1:19 P.M.
MERLIN…………………N/A
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………23 NW @ 3:58 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….23 NW @ 3:58 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………26 NW @ 3:58 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………25 WNW @ 5:27 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..23 NW @ 3:25 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..24 @ 3:24 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……14.5 WNW [348 total miles] ASOS…………………13.5
DAVIS #1……………..14.8 WNW
DAVIS #2……………..15.3 WNW
RMY………………….13.4 WNW
VECTOR……………….14.3
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……TRACE DEPARTURE….-0.12
ASOS………….0.00
TOTAL PRECIPITATION FOR THE MONTH………….4.89 DEPARTURE….-0.06
ASOS………….4.77
TOTAL PRECIPITATION FOR THE YEAR………….15.12 DEPARTURE….-3.55
ASOS………..15.33
PRELIMINARY CLIMATE SUMMARY FOR APRIL CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system gust
RMY: R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M: Missing data
04/01 56/30/43/+2/0.89/T/000/00 44 NW AERO 51 NW RMY 49
04/02 37/24/31/-10/0.00/0.0/614/80 28 NW AERO 32 NNW RMY 30
04/03 48/23/36/-6/0.00/0.0/755/98 24 NW AERO 25 NW RMY 26
04/04 58/33/46/+4/0.00/0.0/734/95 38 NNW AERO 41 NNW RMY 41
04/05 57/41/49/+6/T/T/031/04 41 NNW AERO 48 NNW RMY 50
04/06 61/40/51/+8/0.00/0.0/412/53 26 NNW AERO 25 NNW RMY 31
04/07 57/41/49/+6/0.00/0.0/391/50 23 ENE AERO 21 ENE RMY 22
04/08 59/43/51/+7/0.00/0.0/745/95 22 ENE AERO 22 ENE RMY 24
04/09 69/42/56/+12/0.00/0.0/707/90 24 S AERO M M RMY 26
04/10 75/43/59/+14/0.00/0.0/576/73 26 SSW AERO 28 SSW RMY 30
04/11 53/40/47/+2/T/0.0/000/00 33 ENE AERO 33 ENE RMY 34
04/12 46/37/42/-3/0.05/0.0/000/00 36 ENE AERO 37 ENE RMY 41
04/13 56/37/47/+1/T/0.0/415/52 31 NE AERO 30 NE RMY 33
04/14 56/42/49/+3/0.00/0.0/729/91 22 ESE AERO 23 ESE RMY 22
04/15 51/37/44/-3/0.30/0.0/016/02 26 ESE AERO 25 ESE RMY 28
04/16 39/31/35/-12/2.22/3.6/000/00 48 NNW AERO 58 NNW RMY 58
04/17 45/34/40/-7/0.07/T/040/05 27 NNW AERO 30 NNW RMY 29
04/18 60/38/49/+1/0.00/0.0/666/82 28 NW AERO 28 NW RMY 31
04/19 66/44/55/+7/T/0.0/…/.. 22 SSW AERO 25 SSW RMY 28
04/20 72/45/59/+10/0.00/0.0/…/.. 38 SW AERO 37 WSW RMY 40
04/21 68/32/50/+1/0.48/*T/…/.. 45 S AERO 51 S RMY 51 TSTM
04/22 44/28/36/-13/T/T/…/.. 54 W AERO 55 W RMY 59
04/23 58/32/45/-5/0.00/0.0/…/.. 47 W AERO 48 W RMY 52
04/24 70/44/57/+7/0.00/0.0/…/.. 33 WNW AERO 37 WNW RMY 55
04/25 54/44/49/-1/0.20/0.0/…/.. 23 NNE AERO 20 SSW RMY 24
04/26 55/40/48/-3/0.00/0.0/…/.. 39 NW AERO 40 NW RMY 43
04/27 67/38/53/+2/T/0.0/…/.. 26 W AERO 28 WNW RMY 28
04/28 63/46/55/+3/…./…/…/.. 18 ENE AERO 21 WNW RMY 20
04/29 54/44/48/-4/…./…/…/.. 18 ENE AERO 20 NNE RMY 19
04/30 62/41/52/0/…./…/…/.. 58 WNW AERO 60 WNW RMY 65
*Trace of frozen on 04/21 was hail, 1/8″ diameter, this does not
count as snowfall.
PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system gust
RMY: R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized
M: Missing data
05/01 62/38/50/-3/0.06/0.0/…/.. 31 WNW AERO 35 WNW RMY 40
05/02 The low since midnight is 48F, the daily normal low is 44F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR MAY 2
HIGH 92F IN 2001
LOW 29F IN 1903
PRECIP 1.36 INCHES IN 2006
SNOWFALL TRACE IN 1920, 1941
PEAK GUST 58 MPH S IN 1983
RECORDS FOR MAY 3
HIGH 92F IN 2001
LOW 31F IN 1888
PRECIP 2.25 INS IN 1900
SNOWFALL TRACE IN 1908, 1985
PEAK GUST 71 MPH W IN 2002
TODAY’S REPORT PREPARED BY: Benjamin Turner
