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

SATURDAY, APRIL 24, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0449E
SUNSET:  1836E

SUMMER-LIKE WITH REDUCED VISIBILITY ATOP
GREAT BLUE HILL....

Despite very nice weather, conditions grew windier in the
afternoon hours; and to a little more than a "cool breeze".
Wind is currently westerly with an average speed of 15 mph
and frequent gusts at or above 30 mph. Visibility was
limited due to haze, but the hike up the hill is still
very worth the trip!
 
We continue to hold our "Climb for Climate" event up here.
Our challenge to our Greater Boston community is to climb
up Great Blue Hill to the Observatory and be counted as a
supporter of Mother Earth. We have logged more than 400
people since the start 2 days ago. The weather for today
looks very favorable for a visit given the warmer temperatures.
We continue to provide rooftop tours until 4 P.M. Visibility
is right around 40 miles today.

The high so far today is 70F, this is 11 degrees above the
normal high of 59F. The low since midnight is 44F, which
is 3 degrees above the daily normal low of 41F.

Today's Observations:

7 A.M.
Weather: Few cirrostratus
Temperature: 49F; Dew Point: 32F; Relative Humidity: 50%
Wind: W at 11 kts
Sea-level pressure: 29.92 in Hg, rising, then more slowly
Visibility: 35 miles, hazy
6-hr Max temp: 49F
6-hr Min temp: 44F
24-hr Precip: 0.00 ins.
24-hr Snow: 0.0 ins.
Snow Depth: 0.0 ins.
BHO SA 1155 CLR 35 132/49/32/2711/992/ FEW CS ALQDS/ 8/008 51011
10049 20044

10 A.M.
Weather: Few cirrostratus
Temperature: 63F; Dew Point: 32F; Relative Humidity: 31%
Wind: NW @ 9 kts
Sea-level pressure: 29.93 in Hg; rising steadily
Visibility: 35 miles, hazy
3-hr Precip: 0.00 ins.
3-hr Snow: 0.00 ins.
BHO SA 1455 CLR 35 135/63/32/3109/993/ FEW CS ALQDS/ 8/008 53003

1 P.M.
Weather: Scattered cumulus
Temperature: 70F, Dew point: 27F; Relative Humidity: 20%
Wind: WNW @ 29G29 kts (Peak of 33 MPH (29 kts) WNW at 12:41 P.M.)
Sea-level pressure: 29.89 in Hg; falling, then falling more slowly
Visibility: 35 miles, hazy
6-hr Max temp: 70F
6-hr Min temp: 49F
6-hr Precip: 0.00 ins.
6-hr Snow: 0.0 ins.
Snow Depth: 0 ins.
BHO SA 1755 50 SCT 35 123/70/27/2911G29/989/ HAZY PK WND 2829/41/
8/100 58012 10070 20049


SUMMARY FOR FRIDAY, APRIL 23, 2021

TEMPERATURE (DEGREES F)
MAX.......58     NORMAL.....59
MIN.......32     NORMAL.....41
MEAN......45     NORMAL.....50

DEPARTURE FROM 30-YEAR (1981-2010) NORMAL.......-5
TOTAL DEPARTURE FOR THE MONTH...................+25 [+0.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............20  DEPARTURE......+5
TOTAL HEATING UNITS FOR THE MONTH..............426  DEPARTURE......-27
TOTAL HEATING UNITS FOR THE SEASON............5248  DEPARTURE.....-688
TOTAL HEATING UNITS LAST SEASON TO DATE.......5371  DEPARTURE.....-123

PEAK WIND GUST (MPH):
                     420C/Official..............47 W   @ 10:48 A.M.
                     AEROVANE (south tower).....48 W   @ 10:36 A.M
                     ASOS.......................48 WNW @  1:59 P.M
                     DAVIS #1...................47 W   @ 10:35 A.M
                     DAVIS #2 (south tower).....47 WNW @  1:37 P.M
                     RMY........................52     @ 10:35 A.M
                     VECTOR.....................52     @  1:58 P.M
                     MERLIN.....................46

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL..................34 W   @ 10:58 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................32 W   @  2:00 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE...............35 NW  @  1:38 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............35 WNW @ 10:37 A.M.
MAXIMUM 2-MINUTE RMY AVERAGE....................30 WNW @  1:36 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE.................33     @  1:57 P.M.

AVERAGE WIND SPEED AND DIRECTION:
                     CONTACTING/OFFICIAL......19.2 W [461 total miles]
                     ASOS.....................18.3
                     DAVIS #1.................19.4 W  
                     DAVIS #2.................19.2 W
                     RMY......................16.6 W
                     VECTOR.................. 18.2


PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.......0.00  DEPARTURE....-0.14
                             ASOS.............0.00
TOTAL PRECIPITATION FOR THE MONTH.............4.01  DEPARTURE....+0.39
                             ASOS.............3.91
TOTAL PRECIPITATION FOR THE YEAR.............14.18  DEPARTURE....-3.43
                              ASOS...........14.42

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M.........TRACE  DEPARTURE......0.0
TOTAL SNOWFALL FOR THE MONTH ..................3.6  DEPARTURE.....+0.8
TOTAL SNOWFALL FOR THE SEASON.................76.2  DEPARTURE....+14.2


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/.../..         31 NE   AERO 30 NE   RMY 33
04/14   56/42/49/+3/0.00/0.0/.../..      22 ESE  AERO 23 ESE  RMY 22
04/15   51/37/44/-3/0.30/0.0/.../..      26 ESE  AERO 25 ESE  RMY 28
04/16   39/31/35/-12/2.22/3.6/.../..     48 NNW  AERO 58 NNW  RMY 58
04/17   45/34/40/-7/0.07/T/.../..        27 NNW  AERO 30 NNW  RMY 29
04/18   60/38/49/+1/0.00/0.0/.../..      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/.../.../..      45 S    AERO 51 S    RMY 51
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   The low since midnight is 44F, the daily normal low is 41F


DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)

RECORDS FOR APRIL 24
HIGH 82 IN 2001
LOW 22 IN 1930
PRECIP 2.51 INS IN 1898
SNOWFALL 1.2 INS IN 1967
PEAK GUST 59 MPH NW IN 1962

RECORDS FOR APRIL 25
HIGH 83 IN 2009
LOW 24 IN 1892
PRECIP 1.38 IN. IN 1901
SNOWFALL 0.7 IN. IN 2002
PEAK GUST 66 MPH SE IN 1968


TODAY'S REPORT PREPARED BY: Benjamin Turner