Friday, May 14, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
FRIDAY, MAY 14, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0424E
SUNSET: 1858E
BRIGHTER AND WARMER THAN YESTERDAY ATOP GREAT
BLUE HILL…
Today has generally featured more in the way of sunshine –
particularly in the morning – compared to yesterday’s
considerable diurnal cloudiness. Ski conditions were clear
from early morning through late morning before giving way
to scattered cumulus. Decent visibility has accompanied
the sunshine averaging about 65 miles along with mild
temperatures in the low to middle 70s!
With temperatures peaking so far in the mid-70s and dew
points in the low-30s, dew point depressions are around
40-45F! Thus, humidity readings are in the upper teens
and lower 20s…very dry out there!
Winds are rather gentle here as an area of high approaches
the northeast. Yesterday’s average was 7.3 MPH and today is
around 6.5 MPH since 7AM.
The high so far today is 76F, which is 10 degrees
above the normal high of 66F. The low since midnight
is 49F, which is 2 degrees above the daily normal low
of 47F.
PRELIMINARY STATS FOR APRIL 2021
TEMPERATURE, Deg. F
Avg. Max. 57.2 [+1.5]Avg. Min. 37.8 [+0.1]Mean 47.5 [+0.8]24-hour corrected mean: 47.0
Max. for month: 75F on the 10th
Min. for month: 23F on the 3rd
HEATING DEGREE DAYS
Total heating units: 519 [-32]Total for the season: 5341 [-694]Total for last season: 5521
PRECIPITATION, Inches
Total: 4.89 [+0.45]Greatest in 24 hrs: 2.45 ins. on the 15-16th
SNOWFALL, Inches
Total: 3.6 [+0.6]Greatest in 24 hrs: 3.6 ins. on the 16th
WIND, mph
Avg. uncorrected wind speed: 12.1 mph
Avg. corrected wind speed: 12.5 mph
Prevailing wind direction: WNW [16%]Peak gust and direction: 58 WNW on the 30th
SUNSHINE:
Campbell-Stokes card minutes: 12444 minutes of a possible 23250 or 54%
Astronomical total minutes: 12904 minutes of a possible 24128 or 53%
Today’s Observations:
7 A.M.
Weather: Clear
Temperature: 59F; Dew Point: 33F; Relative Humidity: 37%
Wind: NW at 8 kts
Sea-level pressure: 30.19 in. Hg; rising, then rising more rapidly
Visibility: 65 miles
6-hr Max temp: 59F
6-hr Min temp: 49F
24-hr Precip: 0.00 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0.0 ins.
BHO SA 1155 CLR 224/59/33/3108/019/ 8/000 53013 10059 20049
10 A.M.
Weather: Clear (few cumulus SE-NE)
Temperature: 69F; Dew Point: 33F; Relative Humidity: 26%
Wind: NW @ 8 kts
Sea-level pressure: 30.19 in Hg; rising, then falling
Visibility: 65 miles
3-hr Precip: 0.00 ins.
3-hr Snow: 0.0 ins.
BHO SA 1455 CLR 225/69/33/3107/019/ FEW CU SE-NE/ 8/100 50001
1 P.M.
Weather: Scattered cumulus (virga WSW-NW)
Temperature: 70F, Dew point: 30F; Relative Humidity: 22%
Wind: NW @ 4 kts (wind light & variable)
Sea-level pressure: 30.15 in Hg; falling unsteadily
Visibility: 65 miles
6-hr Max temp: 76F
6-hr Min temp: 53F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 50 SCT 65 209/70/30/3104/015/ VIRGA WSW-NW WND L/V/
8/200 57015 10076 20053
SUMMARY FOR THURSDAY, MAY 13, 2021
TEMPERATURE (DEGREES F)
MAX…….69 NORMAL…..66
MIN…….45 NORMAL…..47
MEAN……57 NORMAL…..56
DEPARTURE FROM 30-YEAR (1981-2010) NORMAL……. +1
TOTAL DEPARTURE FOR THE MONTH……………….-21 [-1.8 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL THRU JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………….8 DEPARTURE…….-1
TOTAL HEATING UNITS FOR THE MONTH…………..157 DEPARTURE……+15
TOTAL HEATING UNITS FOR THE SEASON…………5498 DEPARTURE…..-679
TOTAL HEATING UNITS LAST SEASON TO DATE…….5702 DEPARTURE…..-204
COOLING DEGREE DAYS (SEASON JAN THRU DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………… 0 DEPARTURE……. 0
TOTAL COOLING UNITS FOR THE MONTH…………… 0 DEPARTURE…….-4
TOTAL COOLING UNITS FOR THE SEASON………….. 0 DEPARTURE…….-6
TOTAL COOLING UNITS LAST SEASON TO DATE……… 2 DEPARTURE…….-2
PEAK WIND GUST (MPH):
420C/Official…………..22 WNW @ 1:59 P.M.
AEROVANE (south tower)…..21 WNW @ 1:59 P.M.
ASOS…………………..22 WNW @ 2:00 P.M.
DAVIS #1……………….21 WNW @ 11:57 A.M.
DAVIS #2 (south tower)…..21 WNW @ 1:59 P.M.
RMY……………………23 @ 1:59 P.M.
VECTOR…………………23 @ 1:59 P.M.
MERLIN…………………21
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………14 WNW @ 11:57 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….15 WNW @ 1:44 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………16 WNW @ 1:44 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………16 NW @ 2:01 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..14 NW @ 1:59 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..15 @ 1:40 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…… 7.3 WNW [174 total miles] ASOS………………… 6.6
DAVIS #1………………7.7 NW
DAVIS #2………………7.8 NW
RMY…………………. 7.6 NW
VECTOR………………..8.3
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.00 DEPARTURE….-0.12
ASOS………….0.00
TOTAL PRECIPITATION FOR THE MONTH………….1.78 DEPARTURE….+0.19
ASOS………….1.73
TOTAL PRECIPITATION FOR THE YEAR………….16.84 DEPARTURE….-3.30
ASOS………..17.01
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 76/48/62/+9/0.01/0.0/…/.. 41 SW AERO 41 SW RMY 46
05/03 67/48/58/+5/0.07/0.0/…/.. 21 E AERO 20 E RMY 20
05/04 50/44/47/-7/0.78/0.0/…/.. 36 NNE AERO 32 NNE RMY 37
05/05 48/44/46/-8/0.45/0.0/…/.. 18 ESE AERO 14 ESE RMY 17
05/06 64/45/55/+1/0.00/0.0/…/.. 33 NW AERO 38 NNW RMY 39
05/07 61/43/52/-3/0.00/0.0/…/.. 28 ESE AERO 22 ESE RMY 26
05/08 54/40/47/-8/0.00/0.0/…/.. 24 SSW AERO 23 SSW RMY 25
05/09 66/42/54/-1/T/0.0/…/.. 30 SW AERO 29 SW RMY 34
05/10 60/45/53/-2/0.39/0.0/…/.. 21 W AERO 20 W RMY 20
05/11 63/45/54/-2/0.00/0.0/…/.. 38 WNW AERO 41 WNW RMY 41
05/12 65/41/53/-3/0.00/0.0/…/.. 28 NW AERO M M RMY 31
05/13 69/45/57/+1/0.00/0.0/…/.. 22 WNW AERO 21 WNW RMY 21
05/14 The low since midnight is 49F, the daily normal low is 47F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR MAY 14
HIGH 85F IN 1961
LOW 33F IN 1895
PRECIP 1.93 INCHES IN 2006
PEAK GUST 53 MPH S IN 2009
RECORDS FOR MAY 15
HIGH 93F IN 1900
LOW 36F IN 1947,1985
PRECIP 1.63 INCHES IN 1978
PEAK GUST 53e MPH NE IN 1978, W 2002
TODAY’S REPORT PREPARED BY: Andrew Swanson
