Tuesday, February 18, 2020

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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, FEBRUARY 18, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

THICKENING CLOUD COVER, A TOUCH OF LIGHT SNOW….

Clouds have been the theme yet again, thickening and lowering
through the morning. Some very light snow developed just
before noon and has persisted into the early afternoon hours.
There has only been a trace of snow thus far due to the very
light rate of fall and temperatures above freezing.

An onshore wind has slowly veered from the east this morning
to southeast early this afternoon. This has helped to moisten
the atmosphere. The dew point has risen from 21 early this
morning to 30 early this afternoon.

The high so far today is 37F degrees, this is exactly normal
for the date. The low since midnight is 27F, 7 degrees above
the normal daily minimum of 20F.

Today’s Observations:

7 A.M.
Weather: Overcast altostratus, few stratocumulus NW-NE-SE
Temperature: 31F; Dew Point: 21F; Wind: ESE at 12 kts
Relative Humidity: 66%
Sea-level pressure: 30.45 ins. Hg: rising unsteadily
Visibility: 50 miles
6-hr Max temp: 31F
6-hr Min temp: 27F
24-hr Precip:  0.00 ins.
24-hr Snowfall: 0.0 ins.
BHO SA 1155 E100 OVC 50 312/31/21/1112/045/ FEW BINOVC DSNT
NE-ESE FEW SC NW-NE-SE VIRGA ALQDS/ 8/52/ 52001 10031 20027

10 A.M.
Weather: Scattered stratocumulus, overcast altostratus
Temperature: 35F; Dew Point: 26F; Wind: ESE at 11G17 kts
Relative Humidity: 69%
Sea-level pressure: 30.40 ins. Hg: falling, then more rapidly
Visibility: 40 miles
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1155 25 SCT E90 OVC 40 295/35/26/1111G17/040/ 8/52/ 58017

1 P.M.
Weather: Scattered stratus fractus, overcast stratus, light snow
Temperature: 36F; Dew Point: 30F; Wind: SE at 10 kts
Relative Humidity: 78%
Sea-level pressure: 30.29 ins. Hg: falling rapily
Visibility: 15 miles
6-hr Max temp: 37F
6-hr Min temp: 31F
6-hr Precip: Trace
6-hr Snowfall: Trace
BHO SA 1755 25 SCT 40 OVC 15S- 257/36/30/1210/029/ PCPN VRY LGT
PRESFR TOTAL NEW SNW PST 6 HRS TRACE/ 8/7// 58038 6000 10037 20031

SUMMARY FOR MONDAY, FEBRUARY 17, 2020

TEMPERATURE (DEGREES F)
MAX…..44   NORMAL…..37
MIN…..28   NORMAL…..19
MEAN….36   NORMAL…..28

DEPARTURE FROM 30-YEAR NORMAL………………. +8
TOTAL DEPARTURE FOR THE MONTH……………….+97 [+5.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………29  DEPARTURE……. -8
TOTAL HEATING UNITS FOR THE MONTH…………..550  DEPARTURE…….-98
TOTAL HEATING UNITS FOR THE SEASON…………3779  DEPARTURE……-399
TOTAL HEATING UNITS LAST SEASON TO DATE…….4061  DEPARTURE……-282

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..25 WNW AT 12:59 P.M.
AERO…………………….24 WNW AT 10:22 A.M.
ASOS…………………….24 WNW AT  1:11 P.M.
DAVIS……………………25 WNW AT 10:09 A.M. RMY 24
FASTEST MILE FOR YESTERDAY………………….17 WNW AT  7:11 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….17 W   AT  1:11 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………19 W   AT  1:11 P.M.
AVERAGE WIND SPEED AND DIRECTION………….10.9 WNW
ASOS………………….11.0
DAVIS…………………11.4 WNW [295 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.15
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.89  DEPARTURE……-0.48
ASOS…………..2.00
TOTAL PRECIPITATION FOR THE YEAR………..3.35  DEPARTURE……-3.37
ASOS…………..3.54

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.5
TOTAL SNOWFALL FOR THE MONTH…………….0.6  DEPARTURE…….-7.8
TOTAL SNOWFALL FOR THE SEASON…………..24.8  DEPARTURE……-16.7

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  38/30/34/+8/0.01/T/…./..          14 WSW AERO 14 WSW RMY N/A
02/02  40/30/35/+9/0.00/0.0/…./..        18 W   AERO 18 WNW RMY 18
02/03  44/27/36/+10/0.00/0.0/…./..       28 W   AERO 28 W   RMY 28
02/04  44/33/39/+13/0.00/0.0/…./..       19 E   AERO 16 E   RMY 18
02/05  41/30/36/+10/0.00/0.0/…./..       20 NNW AERO 19 NNW RMY N/A
02/06  31/30/34/+8/0.00/0.0/…./..        29 E   AERO 28 E   RMY 27
02/07  53/25/39/+12/…./0.1/…./..       71 WSW AERO 71 SSW RMY 73
02/08  33/20/27/0/T/T/…./..              46 W   AERO 44 W   RMY 44
02/09  33/15/24/-3/T/T/…./..             30 SSE AERO 29 SSE RMY N/A
02/10  42/33/38/+11/…./0.0/…./..       39 SSW AERO 39 SSW RMY 39
02/11  40/36/38/+11/…./0.0/…./..       24 W   AERO 23 W   RMY N/A
02/12  41/30/36/+9/0.00/0.0/…./..        37 W   AERO 36 W   RMY N/A
02/13  35/31/34/+6/.00/0.0/…./..         29 SSW AERO 29 SSW RMY N/A
02/14  33/8/21/-7/0.00/0.0/…./..         32 WNW AERO 32 NW  RMY 34
02/15  27/4/16/-12/0.00/0.0/…./..        31 SSW AERO 31 SSW RMY N/A
02/16  40/23/32/+4/0.00/0.0/…./..        38 SW  AERO 38 SW  RMY N/A
02/17  44/28/36/+8/0.00/0.0/…./..        25 WNW AERO 24 WNW RMY 24

02/18 The low since midnight is 27F, daily normal minimum is 20F

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

RECORDS FOR FEBRUARY 18
HIGH 65F IN 1981
LOW -10F IN 1958
PRECIP 1.97 INCHES IN 1887
SNOWFALL 9.2 INCHES IN 1952
PEAK GUST 70 MPH S IN 2008

RECORDS FOR FEBRUARY 19
HIGH 66F IN 1981
LOW -5F IN 1923
PRECIP 2.73 INCHES IN 1972
SNOWFALL 12.0 INCHES IN 1893
PEAK GUST 76 MPH ENE IN 1972

TODAY’S REPORT PREPARED BY: Matt Douglas