Thursday, April 1, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
THURSDAY, APRIL 1, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0526E
SUNSET: 1810E
MUCH NEEDED RAINFALL OVERNIGHT, COLDER AIR RETURNS….
Finally we received periods of much needed rainfall overnight
into this morning. Rain fell heavy at times amounting to 1.14
inches through 7 A.M. this morning with an additional 0.05″
falling thereafter.
Yesterday was a warm day, averaging 14 degrees above normal
for the day, however a cold front moved through early
this morning accompanied with a sharp drop in temperatures. A
drop of 9 degrees occurred between 5-6 A.M. from the mid 50s
to the mid 40s. The temperature bottomed out between 8-9 A.M.
at 39 degrees! How’s that for an April fools joke?
Gusty winds with and behind the front helped to usher in the
colder air with a period of strong cold air advection. Gusts
exceeded 40 mph for a few hours following the front, however
has since relaxed back to lighter speeds as we’ve moved into
the afternoon hours.
Clouds and periods of drizzle have lingered into early this
afternoon as well, making for a gloomy day thus far.
The high today, which occurred around 3:50 A.M. is 56F, this
is 6 degrees above the normal high of 50F. The low since
midnight is 39F, which is 7 degrees above the daily normal
low of 32F.
Today’s Observations:
7 A.M.
Weather: Broken stratus fractus, overcast nimbostratus, light drizzle
Temperature: 41F; Dew Point: 41F; Relative Humidity: 100%
Wind: NW @ 23G35 kts, peak wind NW 44 mph at 6:30 A.M.
Sea-level pressure: 29.62 in Hg, falling, then rising
Visibility: 3 miles, fog
6-hr Max temp: 56F
6-hr Min temp: 41F
24-hr Precip: 1.14 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1155 E7 BKN 16 OVC 3L-F 029/41/41/3223G35/962/ R- BCMG L-
PK WND 3238/30/ 8/7// 53001 6070/ 70114 10056 20041
10 A.M.
Weather: Broken stratus fractus, overcast nimbostratus, light drizzle
Temperature: 40F; Dew Point: 39F; Relative Humidity: 96%
Wind: NW @ 16G25 kts, peak wind NW 33 mph at 8:58 A.M.
Sea-level pressure: 29.69 in Hg; rising, then more slowly
Visibility: 10 miles, thin fog
3-hr Precip: 0.05 ins
3-hr Snow: 0.0 ins.
BHO SA 1455 E10 BKN 22 OVC 10L- 053/40/39/3116G25/969/
THN F ALQDS PK WND 3229/58/ 8/7// 51024 6005/
1 P.M.
Weather: Broken stratocumulus, overcast altostratus
Temperature: 43F, Dew point: 38F; Relative Humidity: 82%
Wind: NW @ 9G17 kts
Sea-level pressure: 29.70 in Hg; rising, then falling
Visibility: 60 miles
6-hr Max temp: 43F
6-hr Min temp: 39F
6-hr Precip: 0.05 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 E20 BKN 60 OVC 60 057/43/38/3209G17/970/ L-B00E30/
8/52/ 50004 6005/ 10043 20039
SUMMARY FOR WEDNESDAY, MARCH 31, 2021
TEMPERATURE (DEGREES F)
MAX…….66 NORMAL…..49
MIN…….43 NORMAL…..32
MEAN……55 NORMAL…..41
DEPARTURE FROM 30-YEAR (1981-2010) NORMAL…….. +14
TOTAL DEPARTURE FOR THE MONTH………………..+138 [+4.3 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………10 DEPARTURE……-14
TOTAL HEATING UNITS FOR THE MONTH…………..777 DEPARTURE…..-139
TOTAL HEATING UNITS FOR THE SEASON…………4822 DEPARTURE…..-662
TOTAL HEATING UNITS LAST SEASON TO DATE…….4873 DEPARTURE……-51
PEAK WIND GUST (MPH):
420C/Official…………..41 SSW @ 11:16 A.M.
AEROVANE (south tower)…..45 S @ 1:35 P.M.
ASOS…………………..41 SSW @ 11:16 A.M.
DAVIS #1……………….46 S @ 11:16 A.M.
DAVIS #2 (south tower)…..44 S @ 3:51 P.M.
RMY……………………44 @ 11:15 A.M.
VECTOR…………………45 @ 11:15 A.M.
MERLIN…………………42
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………33 S @ 3:52 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….31 S @ 3:49 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………29 SW @ 1:41 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………33 S @ 4:02 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..30 SSW @ 4:00 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..31 @ 3:46 P.M.
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL……20.0 SSW [481 total miles]ASOS…………………19.7
DAVIS #1……………..18.5 SSW
DAVIS #2……………..20.7 SSW
RMY………………….19.7 SSW
VECTOR……………….20.0
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….1.14 DEPARTURE….+0.97
ASOS………….1.13
TOTAL PRECIPITATION FOR THE MONTH (MARCH)…..2.17 DEPARTURE….-3.41
ASOS………….2.25
TOTAL PRECIPITATION FOR THE YEAR………….11.00 DEPARTURE….-3.17
ASOS………..11.33
SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………. 0.0 DEPARTURE…. -0.2
TOTAL SNOWFALL FOR THE MONTH (MARCH)………. 0.2 DEPARTURE….-12.5
TOTAL SNOWFALL FOR THE SEASON……………..72.6 DEPARTURE….+13.2
PRELIMINARY CLIMATE SUMMARY FOR MARCH 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
03/01 42/24/33/+2/0.13/T/020/03 69 WNW AERO 78 WNW RMY 78
03/02 27/10/19/-12/T/0.1/679/100 63 WNW AERO 71 WNW RMY 69
03/03 45/19/32/0/0.00/0.0/375/55 30 W AERO 30 W RMY 34
03/04 38/22/30/-2/0.00/0.0/520/76 46 NW AERO 51 NW RMY 53
03/05 31/18/25/-7/0.00/0.0/549/80 39 WNW AERO 44 NW RMY 45
03/06 33/15/24/-8/0.00/0.0/675/98 28 WNW AERO 29 WNW RMY 30
03/07 35/15/25/-8/0.00/0.0/686/99 21 NW AERO 22 NW RMY 23
03/08 38/19/29/-4/T/T/389/56 20 NW AERO 20 NW RMY 21
03/09 56/30/43/+10/T/T/…/.. 32 WNW AERO 35 WNW RMY 37
03/10 54/32/43/+10/0.00/0.0/…/.. 29 SSW AERO 29 SSW RMY 31
03/11 71/35/53/+19/0.00/0.0/…/.. 41 SSW AERO 43 SSW RMY 46
03/12 62/42/52/+18/0.00/0.0/…/.. 52 WNW AERO 59 WNW RMY 57
03/13 46/27/37/+3/0.00/0.0/…/.. 53 WNW AERO 59 WNW RMY 57
03/14 45/19/32/-3/0.01/0.1/…/.. 51 WNW AERO 58 NW RMY 58
03/15 27/12/20/-15/0.00/0.0/…/.. 48 NW AERO 47 NW RMY 54
03/16 37/13/25/-10/0.00/0.0/…/.. 22 NNW AERO 22 NNW RMY 23
03/17 52/27/40/+4/0.00/0.0/…/.. 28 S AERO 25 S RMY 29
03/18 46/34/40/+4/0.80/T/…/.. 38 NE AERO 40 NE RMY 42
03/19 39/26/33/-3/T/T/…/.. 37 N AERO 38 N RMY 41
03/20 58/24/41/+4/0.00/0.0/…/.. 23 W AERO 23 W RMY 27
03/21 62/39/51/+14/0.00/0.0/…/.. 22 S AERO 23 S RMY 25
03/22 62/36/49/+12/0.00/0.0/…/.. 21 S AERO 18 S RMY 22
03/23 65/38/52/+14/0.00/0.0/…/.. 22 ESE AERO 18 SE RMY 21
03/24 63/44/54/+16/0.01/0.0/…/.. 22 SSE AERO 21 SSE RMY 21
03/25 67/49/58/+20/0.10/0.0/…/.. 25 S AERO 26 S RMY 26
03/26 63/48/56/+17/0.01/0.0/…/.. 58 W AERO 67 W RMY 63
03/27 63/40/52/+13/0.00/0.0/…/.. 39 WNW AERO 41 WNW RMY 44
03/28 56/37/47/+8/0.80/0.0/…/.. 40 S AERO 41 S RMY 46
03/29 50/35/43/+3/T/0.0/…/.. 58 WNW AERO 62 WNW RMY 63
03/30 58/31/45/+5/0.00/0.0/…/.. 36 S AERO 36 S RMY 37
03/31 66/43/55/+14/0.31/0.0/…/.. 41 SSW AERO 45 S RMY 44
04/01 The low since midnight is 39F, the daily normal low is 32F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR APRIL 1
HIGH 74 IN 1967
LOW 6 IN 1923 [RECORD FOR MONTH]PRECIP 3.47 IN. IN 2004 [RECORD FOR MONTH]SNOWFALL 15.0 IN. IN 1997 [RECORD FOR MONTH]PEAK GUST 75 MPH SSW IN 1962
RECORDS FOR APRIL 2
HIGH 77 IN 1967
LOW 14 IN 1919
PRECIP 1.83 IN. IN 1970
SNOWFALL 6.5 IN. IN 1924
PEAK GUST 76 MPH SSW IN 1970
TODAY’S REPORT PREPARED BY: Matt Douglas
