Sunday, September 20, 2020

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

SUNDAY, SEPTEMBER 20, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

CHILLY AND BREEZY ATOP GREAT BLUE HILL….

Today we observed excellent visibility, being 85 miles
for the majority of the day. Wind has been consistent
at 15 mph from the northeast, with frequent gusts above
20 mph. Skies are partly cloudy, consisting of cumulus,
altocumulus, and a layer of cirrostratus clouds.
Conditions are dry, with dew points near freezing and a
humidity of 40%.

It has been more than one week since we recorded our
last measurable precipitation event. This brings us to
4.14 inches below the annual normal. As of yesterday,
7% of MA is now in an “Extreme Drought” – mainly focused
along the Attleboro, Fall River, and New Bedford corridor.
The rest of the state finds itself in a “Moderate” to
“Severe” drought. The state drought monitor is updated
every Thursday.

-Drought section written by Andrew Swanson

With the high pressure system from the north currently
above the region, temperatures continue to be lower than
seasonal averages. The high so far today is 57F, 13
degrees below the daily normal max of 70F. The low
since midnight is 40F, which is 13 degrees below the
normal low of 53F.

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus and cirrostratus,
few cumulus
Temperature: 43F; Dew Point: 32F; Relative Humidity: 64%
Wind: N at 8 kts
Sea-level pressure: 30.50 ins. Hg: rising steadily
Visibility: 85 miles
6-hr Max temp: 46F
6-hr Min temp: 40F
24-hr Precip: 0.00 ins.
BHO SA 1155 120 SCT 250 SCT 85 329/43/32/3508/050/ FEW CU
ALQDS/ 8/138 51019 10046 20040

10 A.M.
Weather: Scattered cumulus, broken altocumulus and
cirrostratus
Temperature: 57F; Dew Point: 34F; Relative Humidity: 45%
Wind: NNE at 12G21 kts
Sea-level pressure: 30.55 ins. Hg: rising steadily
Visibility: 85 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 30 SCT 120 BKN 250 BKN 85 345/55/34/0212G21/055/
8/138 51016

1 P.M.
Weather: Scattered cumulus, broken altocumulus and
cirrostratus
Temperature: 56F; Dew Point: 32F; Relative Humidity: 39%
Wind: NE at 13G23 kts
Sea-level pressure: 30.54 ins. Hg: rising steadily
Visibility: 85 miles
6-hr Max temp: 57F
6-hr Min temp: 43F
6-hr Precip: 0.00 ins.
BHO SA 1755 30 SCT 120 BKN 250 BKN 85 343/56/32/0413G23/054/
8/138 58002 10057 20043

SUMMARY FOR SATURDAY, SEPTEMBER 19, 2020

TEMPERATURE (DEGREES F)
MAX…..59   NORMAL…..71
MIN…..42   NORMAL…..54
MEAN….51   NORMAL…..62

DEPARTURE FROM 30-YEAR NORMAL……………..-11
TOTAL DEPARTURE FOR THE MONTH……………..-3 [+0.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY………….14  DEPARTURE…..+10
TOTAL HEATING UNITS FOR THE MONTH………….49  DEPARTURE……+2
TOTAL HEATING UNITS FOR THE SEASON…………52  DEPARTURE…..-20
TOTAL HEATING UNITS LAST SEASON TO DATE…….75  DEPARTURE…..-23

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………  0  DEPARTURE……-1
TOTAL COOLING UNITS FOR THE MONTH………… 50  DEPARTURE….. +1
TOTAL COOLING UNITS FOR THE SEASON………..807  DEPARTURE….+221
TOTAL COOLING UNITS LAST SEASON TO DATE……647  DEPARTURE….+160

PEAK WIND GUST FOR YESTERDAY (MPH)
420C/Official…………….23 N   AT  1:57 A.M.
AERO…………………….23 N   AT  2:56 A.M.
ASOS…………………….25 N   AT  3:31 A.M.
DAVIS……………………23 N   AT  2:52 A.M.
RMY N/A  MERLIN N/A
FASTEST MILE FOR YESTERDAY………………….16 N   AT  3:31 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….16 N   AT  3:32 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………17 N   AT  3:32 A.M.
AVERAGE WIND SPEED AND DIRECTION……………8.4 N (202 total miles)
ASOS……………………8.7
DAVIS…………………..8.7 NNE [35 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….-1.93
ASOS…………..0.51
TOTAL PRECIPITATION FOR THE YEAR……….33.32  DEPARTURE….-4.14
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  64/44/54/-10/0.00/…/..            18 S    AERO 18 S    RMY N/A
09/16  72/49/61/-2/0.00/…/..             31 SSW  AERO 31 SSW  RMY 31
09/17  76/57/67/+4/0.00/…/..             26 WSW  AERO 28 W    RMY N/A
09/18  64/48/56/-6/0.00/…/..             28 NE   AERO 30 NNW  RMY N/A
09/19  59/42/51/-11/0.00/…/..            23 N    AERO 23 N    RMY N/A

09/20 The low since midnight is 40F, the daily normal low is 53F

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

RECORDS FOR SEPTEMBER 20
HIGH 90 IN 1983
LOW 34 IN 1979
PRECIP 4.57 INS IN 1899
PEAK GUST 44 MPH NE IN 1972

RECORDS FOR SEPTEMBER 21
HIGH 91 IN 1895
LOW 35 IN 1929, 1956, 1962
PRECIP 5.58 INS IN 1961 (HURRICANE ESTHER; RETURNED AS TS SEPT 25-26TH)
PEAK GUST 186 MPH S IN 1938 (GREAT NEW ENGLAND HURRICANE; CALCULATED GUST, STATION RECORD)

TODAY’S REPORT PREPARED BY: Benjamin Turner