Tuesday, September 15, 2020

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

TUESDAY, SEPTEMBER 15, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

DIMMED SUN DUE TO SMOKE ALOFT, OTHERWISE QUIET AND
COOL…

The talk of the town is all the smoke aloft creating
hazy skies and dimmed sunlight. It has afforded for
some pretty photogenic sunrises and sunsets.

Other than that, there really isn’t much to write home
about today. It has been an exceptionally quiet day with
only a few lower stratocumulus clouds to look at off the
east this morning, shifting to the south this afternoon.

The wind has been pretty much non-existent most of the
day alternating between light and variable and periods
of calm. The average wind speed since 7 A.M. has only
been around 5 mph. The peak gust, which occurred around
9:40 this morning was only 15 mph. There has not been
anything over 10 mph this afternoon so far.

The other story is the continued dry conditions. We
could really use some rain as our rainfall deficit
continues to mount. We’ve only recorded 0.51″ of rain
so far in September, this is 1.24 inches below normal
to date. For the year our deficit has dropped to 3.45
inches below normal. Moderate to severe drought
continues to plague the region.

The high so far today is only 63F, 9 degrees below the
daily normal max of 72F. The low since midnight is 44F,
which is 11 degrees below the normal low of 55F.

Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus NE-S, smoke layer aloft
Temperature: 46F; Dew Point: 40F; Relative Humidity: 79%
Wind: NNW at 7 kts
Sea-level pressure: 30.34 ins. Hg: rising, then more rapidly
Visibility: 80 miles
6-hr Max temp: 49F
6-hr Min temp: 44F
24-hr Precip: 0.00 ins.
BHO SA 1155 CLR 80 273/46/40/3407/034/ FEW SC NE-S K LYR ALF
SUN DMLY VSBL/ 8/500 53019 10049 20044

10 A.M.
Weather: Clear, few stratocumulus NE-SE, smoke layer aloft
Temperature: 59F; Dew Point: 41F; Relative Humidity: 50%
Wind: ENE at 7 kts
Sea-level pressure: 30.35 ins. Hg: rising, then more slowly
Visibility: 80 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 CLR 80 277/59/41/0707/035/ FEW SC NE-SE K LYR ALF/
8/500 51004

1 P.M.
Weather: Clear, few stratocumulus distant S, smoke layer aloft
Temperature: 62F; Dew Point: 41F; Relative Humidity: 45%
Wind: NNE at 2 kts, wind light and variable
Sea-level pressure: 30.31 ins. Hg: falling, then more rapidly
Visibility: 80 miles
6-hr Max temp: 63F
6-hr Min temp: 46F
6-hr Precip: 0.00 ins.
BHO SA 1755 CLR 80 264/62/41/0202/031/ FEW SC DSNT S K LYR ALF
WND L/V/ 8/500 58013 10063 20046

SUMMARY FOR MONDAY, SEPTEMBER 14, 2020

TEMPERATURE (DEGREES F)
MAX…..74   NORMAL…..72
MIN…..50   NORMAL…..55
MEAN….62   NORMAL…..64

DEPARTURE FROM 30-YEAR NORMAL…………….  -2
TOTAL DEPARTURE FOR THE MONTH……………. +22 [+1.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………. 3  DEPARTURE…… 0
TOTAL HEATING UNITS FOR THE MONTH………….11  DEPARTURE…..-17
TOTAL HEATING UNITS FOR THE SEASON…………14  DEPARTURE…..-39
TOTAL HEATING UNITS LAST SEASON TO DATE…….46  DEPARTURE…..-32

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………  0  DEPARTURE……-2
TOTAL COOLING UNITS FOR THE MONTH………… 48  DEPARTURE….. +7
TOTAL COOLING UNITS FOR THE SEASON………..805  DEPARTURE….+227
TOTAL COOLING UNITS LAST SEASON TO DATE……642  DEPARTURE….+163

PEAK WIND GUST FOR YESTERDAY (MPH)
420C/Official…………….29 NNW AT  6:36 P.M.
AERO…………………….33 NNW AT  6:12 P.M.
ASOS…………………….30 NW  AT  6:37 P.M.
DAVIS……………………30 N   AT  6:04 P.M.
RMY 30  MERLIN 29
FASTEST MILE FOR YESTERDAY………………….21 NNW AT  6:37 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….20 NNW AT  6:31 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………20 N   AT  6:31 P.M.
AVERAGE WIND SPEED AND DIRECTION……………12.6 NW
ASOS……………………11.8
DAVIS…………………..12.7 NW [320 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE….-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….0.51  DEPARTURE….-1.24
ASOS…………..0.51
TOTAL PRECIPITATION FOR THE YEAR……….33.32  DEPARTURE….-3.45
ASOS………….34.09

PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

09/01  76/59/68/0/0.00/…/..              22 SSE  AERO 21 SE   RMY 20
09/02  69/59/64/-4/…/…/..              23 SSE  AERO 23 SSE  RMY 24
09/03  75/66/71/+4/…/…/..              22 SSW  AERO 21 SSW  RMY n/a
09/04  82/62/72/+5/0.00/…/..             26 WNW  AERO 26 WNW  RMY 25
09/05  76/55/66/-1/0.00/…/..             25 W    AERO 25 W    RMY 24
09/06  78/58/68/+1/0.00/…/..             24 W    AERO 24 W    RMY n/a
09/07  79/61/70/+4/0.00/…/..             27 SSE  AERO 30 SSE  RMY 28
09/08  82/61/72/+6/0.00/…/..             17 S    AERO 16 S    RMY 17
09/09  80/62/71/+5/0.00/…/..             16 S    AERO 15 S    RMY 16
09/10  81/69/75/+10/0.28/…/..            21 SSW  AERO 21 SSW  RMY n/a
09/11  72/55/64/-1/0.01/…/..             25 N    AERO 25 N    RMY N/A
09/12  68/51/60/-5/0.00/…/..             21 ENE  AERO 21 ENE  RMY 21
09/13  74/53/64/0/0.00/…/..              26 SSW  AERO 26 SSW  RMY 26
09/14  74/50/62/-2/0.00/…/..             29 NNW  AERO 33 NNW  RMY 30

09/15 The low since midnight is 44F, the daily normal low is 55F

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

RECORDS FOR SEPTEMBER 15
HIGH 89F IN 1931
LOW 35F IN 1913
PRECIP 3.93 INCHES IN 1904 (Extra-tropical storm making landfall in New England on 9/15/1904 passing east of BHO and bringing a storm total of 4.11 inches 9/14-15/1904)
PEAK GUST 65e MPH NW, WSW IN 1944 (In the wake of Great Atlantic Hurricane)

RECORDS FOR SEPTEMBER 16
HIGH 91F IN 1939,1941
LOW 39F IN 1984
PRECIP 5.12 INCHES IN 1933 (Hurricane)
PEAK GUST 59 MPH SSE IN 1999

TODAY’S REPORT PREPARED BY: Matt Douglas