Saturday, February 20, 2021

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

SATURDAY, FEBRUARY 20, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0634E
SUNSET:  1723E

OVERCAST WITH VERY LIGHT SNOW LEADS TO SUNSHINE
IN THE EARLY AFTERNOON HOURS….

Snow was the main feature yesterday and the day before,
leaving us with an event total of 9.9 inches!! That puts
us 29.5 inches above normal on the month and 29.8 inches
above normal on the year. Melted snowfall at 7 A.M. was
measured to be 0.57 inches, making us 2.58 inches higher
than average on the month and a half inch higher on the
year.

Light snow continued through this morning into the early
afternoon, only leaving a trace. The sun has since broke
out of the clouds in rapid fashion, bringing with it a
better visibility of 75 miles.

The high so far today is 30F, 8 degrees below the daily
average max of 38F. The low since midnight is 22F, 2 degrees
above the daily average low of 20F.

Today’s Observations:

7 A.M.
Weather: Overcast stratocumulus, snow ending at 6:50 A.M.
Temperature: 23F; Dew Point: 21F; Relative Humidity: 92%
Wind: NW @ 7 kts
Sea-level pressure: 29.97 in Hg; falling, then rising
Visibility: 30 miles, except 20 miles NNW-SE
6-hr Max temp: 24F
6-hr Min temp: 22F
24-hr Precip: 0.57 ins.
24-hr Snow: 7.9 ins.
Snow Depth: 18 ins.
BHO SA 1155 30 OVC 30 148/23/21/3207/997/ VSBY NNW-SE 20
MI S-E50 NEW SNW PST 24 HRS 7.9 INS/ 8/6// 4/018 70057
50004 10024 20022

10 A.M.
Weather: Broken stratocumulus, very light snow
Temperature: 28F; Dew Point: 23F; Relative Humidity: 83%
Wind: NW @ 9G17 kts
Sea-level pressure: 29.96 in Hg; falling steadily
Visibility: 35 miles
3-hr Precip: Trace
3-hr Snow: Trace
BHO SA 1455 30 BKN 35 144/28/23/3209G17/996/ S-B10 PCPN VRY LGT
NEW SNW PST 3 HRS TRACE/ 8/800 600// 58004

1 P.M.
Weather: Overcast stratocumulus, very light snow
Temperature: 28F, Dew point: 21F; Relative Humidity: 74%
Wind: WNW @ 9 kts
Sea-level pressure: 29.96 in Hg, falling then rising
Visibility: 65 miles
6-hr Max temp: 30F
6-hr Min temp: 23F
6-hr Precip: Trace
6-hr Snow: Trace
Snow Depth: 18 ins.
BHO SA 1755 30 OVC 65 146/28/21/3009/996/ S-CTD PCPN VRY LGT NEW
SNW PST 6 HRS TRACE/ 8/8// 4/018 600// 50002 10030 20023

SUMMARY FOR FRIDAY, FEBRUARY 19, 2021

TEMPERATURE (DEGREES F)
MAX…….30   NORMAL…..38
MIN…….24   NORMAL…..20
MEAN……27   NORMAL…..29

DEPARTURE FROM 30-YEAR (1981-2010) NORMAL…… -2
TOTAL DEPARTURE FOR THE MONTH……………….+1 [-0.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………38  DEPARTURE…….+2
TOTAL HEATING UNITS FOR THE MONTH…………..718  DEPARTURE…….-3
TOTAL HEATING UNITS FOR THE SEASON…………3762  DEPARTURE…..-489
TOTAL HEATING UNITS LAST SEASON TO DATE…….3843  DEPARTURE……-81

PEAK WIND GUST (MPH):
420C/Official…………..24 NE  @  3:23 A.M.
AEROVANE (south tower)…..23 NE  @  3:24 A.M.
ASOS…………………..23 NE  @  3:24 A.M.
DAVIS #1……………….24 ENE @  3:23 A.M.
DAVIS #2 (south tower)…..23 ENE @  3:09 A.M.
RMY……………………24     @  3:36 A.M.
VECTOR…………………24     @  3:36 A.M.
MERLIN…………………21

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………16 NE  @  2:34 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….16 ENE @  1:03 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………16 ENE @  1:03 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………16 NE  @  2:34 A.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..15 ENE @  2:31 A.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..16     @  1:00 A.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…… 8.9 NNE [293 total miles] ASOS………………….9.6
DAVIS #1………………9.2 NE
DAVIS #2………………9.2 NE
RMY…………………..9.0 ENE
VECTOR………………..9.3

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.57  DEPARTURE….+0.42
ASOS………….0.54
TOTAL PRECIPITATION FOR THE MONTH………….5.24  DEPARTURE….+2.58
ASOS………….5.42
TOTAL PRECIPITATION FOR THE YEAR…………..7.56  DEPARTURE….+0.55
ASOS…………7.77

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………..7.9  DEPARTURE…. +7.4
TOTAL SNOWFALL FOR THE MONTH………………38.9  DEPARTURE….+29.5
TOTAL SNOWFALL FOR THE SEASON……………..72.3  DEPARTURE….+29.8

PRELIMINARY CLIMATE SUMMARY FOR FEBRUARY 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

02/01   32/21/27/+1/1.86/12.7/000/00      53 NE   AERO 65 NE   RMY 62
02/02   34/29/32/+6/0.91/1.6/000/00       52 NNE  AERO 55 NE   RMY 58
02/03   34/26/30/+4/0.01/0.2/036/06       20 NW   AERO 20 NW   RMY 22
02/04   37/26/32/+6/0.02/0.7/158/26       23 NW   AERO 22 NW   RMY M
02/05   39/26/33/+7/0.01/T/000/00         33 S    AERO 32 S    RMY 30
02/06   40/28/34/+8/0.00/0.0/595/97       42 WSW  AERO 41 WSW  RMY 47
02/07   35/25/30/+3/0.71/11.6/000/00      27 WNW  AERO 28 WNW  RMY 30
02/08   27/13/20/-7/0.00/0.0/619/100      29 NW   AERO 31 WNW  RMY 32
02/09   27/18/23/-4/0.17/2.2/000/00       16 N    AERO 16 N    RMY 17
02/10   31/15/23/-4/0.00/0.0/…/..       26 WNW  AERO 25 WNW  RMY 28
02/11   31/15/23/-4/0.00/0.0/…/..       28 NW   AERO 26 NW   RMY 31
02/12   25/8/17/-10/0.00/0.0/…/..       32 NW   AERO 35 NW   RMY 36
02/13   27/15/21/-7/0.00/0.0/…/..       20 NNW  AERO 20 NNW  RMY 23
02/14   34/24/29/+1/0.00/0.0/…/..       19 ENE  AERO 16 ENE  RMY 19
02/15   31/27/29/+1/0.11/0.0/…/..       21 NNE  AERO 21 NNE  RMY 22
02/16   44/29/37/+9/0.63/0.0/…/..       39 W    AERO 41 W    RMY 43
02/17   30/19/25/-3/0.00/0.0/…/..       40 W    AERO 41 WNW  RMY 40
02/18   29/21/25/-4/…/…/…/..        24 ENE  AERO 24 ENE  RMY 25
02/19   30/24/27/-2/0.00/0.0/…/..       24 NE   AERO 23 NE   RMY 24

02/20 The low since midnight is 22F, the daily normal low is 20F

DAILY RECORDS

02/01 -RECORD SNOWFALL OF 12.7 INS, BREAKING PREVIOUS RECORD
OF 11.0 INS SET IN 1898
02/01 -RECORD PRECIPITATION OF 1.86 INS, BREAKING PREVIOUS
RECORD OF 1.30 INS SET IN 1898

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

RECORDS FOR FEBRUARY 20
HIGH 68F IN 2018
LOW -4F IN 1966
PRECIP 1.90 INCHES IN 1934
SNOWFALL 15.0 INCHES IN 1921,1934
PEAK GUST 78 MPH NW IN 1972

RECORDS FOR FEBRUARY 21
HIGH 70F IN 2018
LOW -6F IN 1950
PRECIP 2.42 INCHES IN 1898
SNOWFALL 9.0 INCHES IN 1929
PEAK GUST 72 MPH WNW IN 1967

TODAY’S REPORT PREPARED BY: Benjamin Turner