Monday, September 14, 2020

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

MONDAY, SEPTEMBER 14, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

RATHER PLEASANT DAY WITH FILTERED SUNSHINE AND LOWERING
HUMIDITY….

We started the day with a lot of clouds and a bit of a
sticky air mass, but as the day has progressed, clouds
have moved out and humidity levels have dropped off.

The dew point started the day in the low 60s, but has
now dropped into the low 50s by early afternoon, and
are likely to continue dropping into the 40s by late
afternoon.

Despite the clouds mostly moving out this afternoon,
the sun is still being filtered. This milky appearance
in the sky is due to a smoke layer aloft, courtesy of
the wildfires on the west coast. It’s interesting that
the filtering of the sun has been enough to limit
cumulus development today. We’ve been mostly observing
flatter stratocumulus and small cumulus, despite the
temperature rising into the low to mid 70s.

The wind started the day out of the southwest, then
gradually veered around to the northwest late this
morning. This northwest flow is helping to usher in
the drier air mass. The wind has been a bit busy
today as well with gusts up to 27 mph so far today.

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 1.11 inches below normal
to date. For the year our deficit has dropped to 3.32
inches below normal. Moderate to severe drought
continues to plague the region.

The high so far today 73F, a degree above the daily
normal max of 72F. The low since midnight is 64F, which
is 9 degrees above the normal low of 55F.

PRELIMINARY STATS FOR AUGUST 2020

TEMPERATURE, Deg. F
Avg. Max. 82.5 [+3.3] Avg. Min. 64.3 [+2.5] Mean      73.4 [+2.9] 24-hour corrected mean: 72.3
Max. for month: 94F on the 10th
Min. for month: 54F on the 31st

HEATING DEGREE DAYS
Total heating units:     2 [-14] Total for the season:    3 [-22] Total for last season:  12

COOLING DEGREE DAYS
Total cooling units:    270  [+84] Total for the season:   757  [+220] Total for last season:  622

PRECIPITATION, Inches
Total: 3.74 [-0.29] Greatest in 24 hrs: 2.21 ins. on the 23rd

WIND, mph
Avg. uncorrected wind speed: 10.0 mph
Avg. corrected wind speed:   10.6 mph
Prevailing wind direction:   SSW [12%] Peak gust and direction:     67 SSE on the 4th

SUNSHINE:
Campbell-Stokes card minutes: 15318 minutes of a possible 24780 or 62%
Astronomical total minutes: 15885 minutes of a possible 25709 or 62%

Today’s Observations:

7 A.M.
Weather: Broken altocumulus/altocumulus castellanus,
broken cirrostratus, overcast cirrus
Temperature: 65F; Dew Point: 61F; Relative Humidity: 86%
Wind: WNW at 9 kts
Sea-level pressure: 30.03 ins. Hg: rising, then more rapidly
Visibility: 60 miles
6-hr Max temp: 65F
6-hr Min temp: 64F
24-hr Precip: 0.00 ins.
BHO SA 1155 E140 BKN 200 BKN 250 OVC 60 169/65/61/2909/003/
VIRGA E-SE SUN DMLY VSBL/ 8/087 53016 10065 20064

10 A.M.
Weather: Scattered stratocumulus/cumulus, scattered cirrostratus,
thin overcast cirrus, smoke layer aloft
Temperature: 70F; Dew Point: 54F; Relative Humidity: 57%
Wind: NW at 14G22 kts
Sea-level pressure: 30.06 ins. Hg: rising, then more slowly
Visibility: 70 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 35 SCT 200 SCT 250 -OVC 60 180/70/54/3214G22/006/
K LYR ALFT/ 8/408 51011

1 P.M.
Weather: Scattered stratocumulus/cumulus, thin scattered cirrus,
smoke layer aloft
Temperature: 73F; Dew Point: 51F; Relative Humidity: 46%
Wind: NW at 11 kts
Sea-level pressure: 30.06 ins. Hg: rising, then falling
Visibility: 70 miles
6-hr Max temp: 73F
6-hr Min temp: 65F
6-hr Precip: 0.00 ins.
BHO SA 1755 45 SCT 250 -SCT 70 179/73/51/3311/006/
K LYR ALFT/ 8/401 58001 10073 20065

SUMMARY FOR SUNDAY, SEPTEMBER 13, 2020

TEMPERATURE (DEGREES F)
MAX…..74   NORMAL…..73
MIN…..53   NORMAL…..56
MEAN….64   NORMAL…..64

DEPARTURE FROM 30-YEAR NORMAL…………….   0
TOTAL DEPARTURE FOR THE MONTH……………. +24 [+1.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..1  DEPARTURE……-2
TOTAL HEATING UNITS FOR THE MONTH…………..8  DEPARTURE…..-17
TOTAL HEATING UNITS FOR THE SEASON…………11  DEPARTURE…..-39
TOTAL HEATING UNITS LAST SEASON TO DATE…….40  DEPARTURE…..-29

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………  0  DEPARTURE……-2
TOTAL COOLING UNITS FOR THE MONTH………… 48  DEPARTURE….. +9
TOTAL COOLING UNITS FOR THE SEASON………..805  DEPARTURE….+229
TOTAL COOLING UNITS LAST SEASON TO DATE……642  DEPARTURE….+163

PEAK WIND GUST FOR YESTERDAY (MPH)
420C/Official…………….26 SSW AT  3:06 P.M.
AERO…………………….26 SSW AT  2:02 P.M.
ASOS…………………….27 SSW AT  2:37 P.M.
DAVIS……………………27 SW  AT  2:36 P.M.
RMY 26  MERLIN 26
FASTEST MILE FOR YESTERDAY………………….21 SSW AT  2:34 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….21 SSW AT  2:37 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………20 SSW AT  2:36 P.M.
AVERAGE WIND SPEED AND DIRECTION……………10.9 SSE
ASOS……………………10.6
DAVIS…………………..10.5 S [189 deg.]

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……….0.51  DEPARTURE….-1.11
ASOS…………..0.51
TOTAL PRECIPITATION FOR THE YEAR……….33.32  DEPARTURE….-3.32
ASOS………….34.09

PRELIMINARY CLIMATE SUMMARY FOR AUGUST 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

08/01  87/66/77/+5/0.00/866/100            18 S    AERO 21 S    RMY 19
08/02  85/69/77/+5/0.02/320/37             36 S    AERO 37 S    RMY 38
08/03  91/75/83/+11/0.00/715/83            36 WSW  AERO 38 SW   RMY 36
08/04  83/71/77/5/0.21/094/11              67 SSE  AERO 71 S    RMY 70
08/05  90/68/79/+7/0.00/668/78             28 SW   AERO 30 SW   RMY 29
08/06  84/65/75/3/0.00/701/82   20 W    AERO 17 W    RMY 19
08/07  79/65/72/0/T/136/16                 16 NE   AERO 16 NE   RMY N/A
08/08  83/64/74/+2/0.00/612/72             20 S    AERO 20 S    RMY 19
08/09  90/65/78/+6/0.00/661/78             26 SSW  AERO 26 SSW  RMY 26
08/10  94/69/82/+11/0.00/727/86            22 W    AERO 20 W    RMY 20
08/11  92/72/82/+11/0.00/708/84            31 SSW  AERO 35 SSW  RMY 31  TSTM
08/12  93/74/84/+13/0.00/647/77            22 SSW  AERO 22 SW   RMY 19
08/13  88/71/80/+9/0.00/528/63             18 ENE  AERO 18 NE   RMY 18
08/14  82/67/75/+4/0.00/618/74             23 ENE  AERO 23 ENE RMY N/A
08/15  67/62/65/-6/T/000/00                33 NNE  AERO 32 NNE  RMY N/A
08/16  69/62/66/-5/0.34/000/00             26 ENE  AERO 28 ENE  RMY 26
08/17  73/59/66/-5/0.04/339/41             25 NE   AERO 24 NE   RMY N/A
08/18  84/63/74/+3/0.23/784/95             23 W    AERO 23 W    RMY 24
08/19  81/59/70/0/0.03/526/64              26 W    AERO 28 W    RMY 27
08/20  80/56/68/-2/0.00/804/98             22 W    AERO 21 W    RMY 22
08/21  88/61/75/+5/0.00/719/88             28 SW   AERO 26 SW   RMY 28
08/22  85/66/76/+6/0.26/521/64             18 NNE  AERO 16 S    RMY 16
08/23  89/63/76/+6/2.21/552/68             60 WNW  AERO 53 WNW  RMY 58  TSTM HAIL
08/24  87/67/77/+7/0.00/493/61             18 S    AERO 18 S    RMY 19  TSTM
08/25  86/65/76/+7/0.01/492/61             35 NNW  AERO 37 NNW  RMY 35
08/26  74/56/65/-4/0.00/780/97             29 NW   AERO 32 NW   RMY N/A
08/27  68/57/63/-6/0.33/008/01             18 SSE  AERO 20 SSE  RMY 20  TSTM
08/28  80/59/70/+1/0.00/559/70             20 W    AERO 20 W    RMY N/A
08/29  74/65/70/+1/0.06/000/00             32 W    AERO 32 W    RMY N/A
08/30  75/57/66/-2/0.00/793/100            36 W    AERO 36 W    RMY N/A
08/31  75/54/65/-3/0.00/514/65             20 S    AERO 20 S    RMY 20

DAILY RECORDS FOR AUGUST 2020

8/23/20: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 89F,
BREAKS PREVIOUS RECORD of 88F SET IN 1918, 1947, 1949, 1996

8/23/20: DAILY RECORD PRECIPITATION OF 2.21 INS,
BREAKS PREVIOUS RECORD OF 2.09 INS SET IN 2010

8/23/20: DAILY RECORD PEAK WIND GUST OF 60 MPH,
TIES PREVIOUS RECORD OF 60 MPH SET IN 1940

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 The low since midnight is 64F, 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 14
HIGH 90F IN 1931
LOW 34F IN 1911
PRECIP 4.38 INCHES IN 1944 (Great Atlantic Hurricane in 1944)
PEAK GUST 96e MPH E IN 1944 (Great Atlantic Hurricane in 1944)

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)

TODAY’S REPORT PREPARED BY: Matt Douglas