Tuesday, September 28, 2021
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
TUESDAY, SEPTEMBER 28, 2021
ALL TIMES ARE IN EASTERN STANDARD TIME
SUNRISE: 0538E
SUNSET: 1730E
SHOWERS AND THUNDERSTORMS OVER THE REGION AHEAD OF A COLD FRONT….
The day started on the dry side, albeit with a lot of cloud cover.
Thunderstorms reached the hill by mid morning bringing occasional
lightning and a brief wind gust to around 23mph. Rainfall associated
with the first thunderstorm didn’t amount to much despite a very
brief period of heavy rain. 0.06″ was measured at the 10 A.M.
observation.
Periods of rain have continued into the afternoon with an additional
0.15″ falling by the 1 P.M. observation.
Other than the brief gust with the thunderstorm, the winds have been
rather light averaging between 5-10mph most of the day.
Humidity levels increased today ahead of the cold front and of
course due to the rain. The dew point started in the upper 50s this
morning, but has reached the low-mid 60s early this afternoon. Much
drier air will be realized once the cold front passes the region
this evening.
Visibility has been limited with all the rain, starting the day at
around 35 miles, but staying generally under 10 miles thereafter.
The high so far today is 67F, 1 degree below the normal max of 68F.
The low since midnight is 61F, 10 degrees above the normal low of 51F.
Today’s Observations:
7 A.M.
Weather: Broken Altocumulus, Broken Altocumulus castellanus,
Thin Overcast Cirrus, Few Breaks in Overcast All Quadrants
Temperature: 63F; Dew Point: 57F; Relative Humidity: 80%
Wind: SSW @ 9 kts
Sea-level pressure: 1009.2 mb; 29.80 in. Hg; rising, then falling
Visibility: 35 miles
6-hr Max temp: 65F
6-hr Min temp: 62F
24-hr Precip: Trace
BHO SA 1155 E100 BKN 130 BKN 250 -OVC 35 092/63/57/2109/980/
FEW BINOVC ALQDS VIRGA N-NNE/ 8/081 50000 70000 10065 20062
10 A.M.
Weather: Scattered Cumulonimbus, Broken Altocumulus, Overcast Nimbostratus,
Thunderstorm with Light Rain Showers
Temperature: 61F; Dew Point: 60F; Relative Humidity: 96%
Wind: WSW @ 6 kts
Sea-level pressure: 1009.4 mb; 29.81 in Hg; rising unsteadily
Visibility: 5 miles, Fog
3-hr Precip: 0.06 ins.
BHO SA 1455 45 SCT E65 BKN 100 OVC 5TRW-F 094/61/60/2406/981/
CB OVHD-S-W MVG E OCNL LTGICCCCG VSBY ESE-SE 10 WND 18V28/ 8/37/
52002 6006/
1 P.M.
Weather: Scattered stratocumulus, Overcast Nimbostratus,
Few Stratus Fractus All Quadrants, Light Rain
Temperature: 64F, Dew point: 63F; Relative Humidity: 96%
Wind: WSW @ 5 kts, Wind Light
Sea-level pressure: 1008.7 mb; 29.79 in Hg; falling, then more rapidly
Visibility: 8 miles, Thin Fog
6-hr Max temp: 67F
6-hr Min temp: 61F
6-hr Precip: 0.21 ins.
BHO SA 1755 60 SCT 100 OVC 8R- 087/64/63/2505/979/ FEW STFRA ALQDS
R-B19 WND LGT/ 8/67/ 58007 6021/ 10067 20061
SUMMARY FOR MONDAY, SEPTEMBER 27, 2021
TEMPERATURE (DEGREES F)
MAX…….73 NORMAL…..68
MIN…….52 NORMAL…..51
MEAN……63 NORMAL…..60
DEPARTURE FROM 30-YEAR (1991-2020) NORMAL…………. +3
TOTAL DEPARTURE FOR THE MONTH…………………….+50 [+1.7 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON: JUL 2021 THRU JUN 2022)
TOTAL HEATING UNITS FOR YESTERDAY…………….2 DEPARTURE……..-4
TOTAL HEATING UNITS FOR THE MONTH……………18 DEPARTURE…….-61
TOTAL HEATING UNITS FOR THE SEASON…………..46 DEPARTURE…….-51
TOTAL HEATING UNITS LAST SEASON TO DATE………97 DEPARTURE…….-51
COOLING DEGREE DAYS (SEASON: JAN 2021 THRU DEC 2021)
TOTAL COOLING UNITS FOR YESTERDAY…………….0 DEPARTURE……..-1
TOTAL COOLING UNITS FOR THE MONTH……………62 DEPARTURE…….-10
TOTAL COOLING UNITS FOR THE SEASON………….712 DEPARTURE…….+44
TOTAL COOLING UNITS LAST SEASON TO DATE……..820 DEPARTURE……-108
PEAK WIND GUST (MPH):
Official……………….30 SW @ 7:58 P.M.
AEROVANE (south tower)…..30 SW @ 9:08 P.M.
VECTOR #2 (south tower)….31 @ 7:38 P.M.
DAVIS #2 (south tower)…..29 WSW @ 7:58 P.M.
ASOS………..OUT OF SERVICE D/T RENOVATIONS
VECTOR #1……OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…….OUT OF SERVICE D/T RENOVATIONS
RMY…………OUT OF SERVICE D/T RENOVATIONS
MERLIN………OUT OF SERVICE D/T RENOVATIONS
FASTEST MILE:
CONTACTING ANEMOMETER/OFFICIAL………………23 SW @ 7:34 P.M.
MAXIMUM 2-MINUTE VECTOR #2 AVERAGE…………..22 @ 7:47 P.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE……………22 SW @ 7:47 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE…….OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE VECTOR #1 AVERAGE..OUT OF SERVICE D/T RENOVATIONS
MAXIMUM 2-MINUTE RMY AVERAGE……..OUT OF SERVICE D/T RENOVATIONS
AVERAGE WIND SPEED AND DIRECTION:
CONTACTING/OFFICIAL…….12.7 SW [304 total miles]
VECTOR #2…………….. N/A
DAVIS #2………………13.2 WSW
RMY……………..OUT OF SERVICE D/T RENOVATIONS
ASOS…………….OUT OF SERVICE D/T RENOVATIONS
VECTOR #1………..OUT OF SERVICE D/T RENOVATIONS
DAVIS #1…………OUT OF SERVICE D/T RENOVATIONS
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST):
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M……TRACE DEPARTURE….-0.15
TOTAL PRECIPITATION FOR THE MONTH………….6.23 DEPARTURE….+2.63
TOTAL PRECIPITATION FOR THE YEAR………….46.57 DEPARTURE….+8.62
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 68/56/62/-7/1.47/000/00 34 NNE AERO 37 NNE RMY N/A
09/02 71/55/63/-6/2.53/322/41 49 ENE AERO 52 ENE RMY N/A
09/03 72/52/62/-6/0.00/735/94 23 NW AERO 23 NW RMY N/A
09/04 76/55/66/-2/0.00/757/97 22 WNW AERO 21 WNW RMY N/A
09/05 72/60/66/-2/0.04/008/01 27 S AERO 29 S RMY N/A
09/06 80/61/71/+3/0.00/557/72 24 WNW AERO 25 WNW RMY N/A
09/07 78/57/68/+1/0.00/732/95 23 WSW AERO 22 WSW RMY N/A
09/08 81/61/71/+4/0.00/646/84 43 S AERO 45 S RMY N/A
09/09 71/64/68/+1/0.90/000/00 33 S AERO 36 S RMY N/A
09/10 74/55/65/-1/0.04/595/78 31 NW AERO 32 WNW RMY N/A
09/11 75/51/63/-3/0.00/730/96 24 SW AERO 24 SW RMY N/A
09/12 79/60/70/+4/0.00/591/78 33 SW AERO 32 SW RMY N/A
09/13 77/62/70/+5/0.06/559/74 22 NW AERO 23 NW RMY N/A
09/14 75/59/67/+2/0.00/444/59 23 S AERO 25 S RMY N/A
09/15 82/65/74/+9/T/539/72 32 SSW AERO 35 SSW RMY N/A
09/16 69/61/65/+1/0.27/037/05 24 ENE AERO 24 ENE RMY N/A TSTM
09/17 66/60/63/-1/0.02/000/00 22 NE AERO 23 NE RMY N/A
09/18 74/62/68/+5/0.04/207/28 17 WNW AERO 18 WNW RMY N/A TSTM
09/19 71/57/64/+1/0.15/619/84 23 NNE AERO 24 NNE RMY N/A
09/20 71/55/63/0/0.00/588/80 20 SE AERO 20 SE RMY N/A
09/21 75/55/65/+3/0.00/…/.. 19 SSE AERO 20 SSE RMY N/A
09/22 75/65/70/+8/0.02/…/.. 30 S AERO 30 S RMY N/A
09/23 78/65/72/+10/0.08/…/.. 36 SSE AERO 37 SSE RMY N/A
09/24 75/62/69/+8/0.02/…/.. 43 SSE AERO 45 SSE RMY N/A
09/25 74/59/67/+6/0.02/…/.. 14 N AERO 14 NNW RMY N/A
09/26 73/54/64/+4/0.57/…/.. 33 WNW AERO 32 WNW RMY N/A
09/27 73/52/63/+3/T/…/.. 30 SW AERO 30 SW RMY N/A
09/28 The low since midnight is 61F, the daily normal low is 51F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated)
RECORDS FOR SEPTEMBER 28
HIGH 86F IN 2014
LOW 33F IN 1897,1947
PRECIP 2.46 INCHES IN 2004
PEAK GUST 69 MPH NE IN 1962
RECORDS FOR SEPTEMBER 29
HIGH 85F IN 1952
LOW 28F IN 1914 (SEPTEMBER MINIMUM RECORD)
PRECIP 2.61 INCHES IN 1907
PEAK GUST 62 MPH S IN 2005
TODAY’S REPORT PREPARED BY: Augustin Busschaert/Matt Douglas
