Friday, February 19, 2021

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

FRIDAY, FEBRUARY 19, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0635E
SUNSET:  1722E

OVERCAST WITH PERSISTENT LIGHT SNOW ATOP GREAT BLUE HILL….

It is once again snowing on the summit…a common sight this
month! A few interesting facts as we dig through the 2020-2021
snowfall files so far this winter:

1) Today marks the 21st day of measurable snow,

2) Today marks 24 consecutive days with a measurable
snow depth,

3) Today puts us over the seasonal snowfall average of
62.7 inches. We are currently sitting at 64.4 inches through
7AM this morning.

Light to moderate snow has been occurring since yesterday evening.
At 7AM, 2.0 inches fell overnight. As of 1PM, the running storm
total escalated to 3.3 inches. Skies are overcast with visibility
peaking 1 mile at best, though 1/4 mile in fog has dominated.
Winds are primarily out of the northeast averaging 7 MPH.

The high so far today is 30F, 8 degrees below the daily
average max of 38F. The low since midnight is 24F, 4 degrees
above the daily average low of 20F.

Today’s Observations:

7 A.M.
Weather: Sky obscured, Vertical visibility 300ft, Light snow
Temperature: 25F; Dew Point: 25F; Relative Humidity:100%
Wind: NNE @ 8 kts
Sea-level pressure: 30.24 in Hg; falling, then rising
Visibility: 1 mile, fog
6-hr Max temp: 27F
6-hr Min temp: 24F
24-hr Precip: 0.24 ins.
24-hr Snow: 2.0 ins.
Snow Depth: 12 ins.
BHO SA 1155 X W3 1S-F 240/25/25/0308/024/ S-CTD TOTAL NEW SNW
PST 24 HRS 2.0 INS/ 8//// 4/012 55001 70024 10027 20024

10 A.M.
Weather: Sky obscured, Vertical visibility 300ft, Light snow
Temperature: 28F; Dew Point: 28F; Relative Humidity: 100%
Wind: NE @ 8G15 kts
Sea-level pressure: 30.19 in Hg; falling, then falling more rapidly
Visibility: 1/4 mile
3-hr Precip: 0.06 ins.
3-hr Snow: 0.7 ins.
BHO SA 1455 X W3 1/4S-F 222/28/28/0508G15/019/ S-CTD TOTAL
NEW SNW PST 3 HRS 0.7 INS/ 8//// 58018 6006/

1 P.M.
Weather: Sky obscured, Vertical visibility 200ft, Light snow
Temperature: 29F, Dew point: 29F; Relative Humidity: 100%
Wind: NNE @ 8 kts
Sea-level pressure: 30.12 in Hg, falling, then falling more rapidly
Visibility: 1/4 mile
6-hr Max temp: 30F
6-hr Min temp: 25F
6-hr Precip: 0.12 ins.
6-hr Snow: 1.3 ins.
Snow Depth: 13 ins.
BHO SA 1755 X W2 1/4S-F 201/29/29/0208/012/ S-CTD TOTAL
NEW SNW PST 6 HRS 1.3 INS/ 8//// 4/013 58021 6012/ 10030
20025

SUMMARY FOR THURSDAY, FEBRUARY 18, 2021

TEMPERATURE (DEGREES F)
MAX…….29   NORMAL…..37
MIN…….21   NORMAL…..20
MEAN……25   NORMAL…..29

DEPARTURE FROM 30-YEAR (1981-2010) NORMAL…… -4
TOTAL DEPARTURE FOR THE MONTH……………….+3 [0.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………40  DEPARTURE…….+3
TOTAL HEATING UNITS FOR THE MONTH…………..680  DEPARTURE…….-4
TOTAL HEATING UNITS FOR THE SEASON…………3724  DEPARTURE…..-491
TOTAL HEATING UNITS LAST SEASON TO DATE…….3812  DEPARTURE……-88

PEAK WIND GUST (MPH):
420C/Official…………..24 ENE @  8:59 P.M.
AEROVANE (south tower)…..24 ENE @  8:23 P.M.
ASOS…………………..25 ENE @  8:59 P.M.
DAVIS #1……………….24 E   @  8:15 P.M.
DAVIS #2 (south tower)…..24 ENE @  8:15 P.M.
RMY……………………25     @  8:14 P.M.
VECTOR…………………26     @  8:59 P.M.
MERLIN…………………24

FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………16 ENE @  8:19 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….16 ENE @  8:17 P.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE……………17 E   @  8:16 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………19 ENE @  8:17 P.M.
MAXIMUM 2-MINUTE RMY AVERAGE………………..16 ESE @  8:13 P.M.
MAXIMUM 2-MINUTE VECTOR AVERAGE……………..16     @  8:13 P.M.

AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…… 6.5 NE [157 total miles] ASOS………………….6.5
DAVIS #1………………6.9 NE
DAVIS #2………………6.9 NE
RMY…………………..6.6 ENE
VECTOR………………..7.1

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…….0.24  DEPARTURE….+0.09
ASOS………….0.23
TOTAL PRECIPITATION FOR THE MONTH………….4.67  DEPARTURE….+2.16
ASOS………….4.88
TOTAL PRECIPITATION FOR THE YEAR…………..6.99  DEPARTURE….+0.13
ASOS…………7.23

SNOWFALL (INCHES) THROUGH THIS MORNING (EST):
TOTAL SNOWFALL 24 HOURS ENDING 7 A.M………..2.0  DEPARTURE…. +1.5
TOTAL SNOWFALL FOR THE MONTH………………31.0  DEPARTURE….+22.1
TOTAL SNOWFALL FOR THE SEASON……………..64.4  DEPARTURE….+22.4

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 The low since midnight is 24F, 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 19
HIGH 66F IN 1981
LOW -5F IN 1923
PRECIP 2.73 INCHES IN 1972
SNOWFALL 8.9 INCHES IN 1964
PEAK GUST 76 MPH ENE IN 1972

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

TODAY’S REPORT PREPARED BY: Andrew Swanson