Friday, September 20, 2019
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, SEPTEMBER 20, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME
PARTLY CLOUDY WITH DECENT VISIBILITY AND
A RELATIVELY LIGHT WESTERLY WIND….
Today we observed gradually drying weather conditions
and partly cloudy skies. Despite the relative humidity
dropping to 30%, visibility stayed at 65 miles for the
majority of the day. Wind remained light and westerly,
advecting some warm air into the region. Accompanied with
unhindered heating from the sun’s rays, temperatures are
the highest they have been all week.
The high so far today has been 76F. This is 6 degrees
below the normal maximum of 70F. The low since midnight
is 50F, 3 degrees below the normal of 53F.
PRELIMINARY STATS FOR AUGUST 2019
TEMPERATURE, Deg. F
Avg. Max. 80.4 [+1.2]
Avg. Min. 62.1 [+0.3]
Mean 71.3 [+0.8]
24-hour corrected mean: 70.5
Max. for month: 92F on the 19th
Min. for month: 51F on the 26th
COOLING DEGREE DAYS
Total cooling units: 211 [+22]
Total for the season: 619 [+82]
Total for last season: 753
PRECIPITATION, Inches
Total: 1.83 [-2.21]
Greatest in 24 hrs: 0.81 ins. on the 28th-29th
WIND, mph
Avg. uncorrected wind speed: 9.1 mph
Avg. corrected wind speed: 9.8 mph
Prevailing wind direction: W at 15%
Peak gust and direction: 33 SW on the 21st
SUNSHINE:
Campbell-Stokes card minutes: 16404 minutes of possible 24780 or 66%
Astronomical total minutes: 17074 minutes of possible 25768 or 66%
Today’s Observations:
7 A.M.
Weather: Scattered altocumulus
Temperature: 53F; Dew Point: 44F; Wind: W at 8 kts
Sea-level pressure: 30.22 ins. Hg, rising steadily
Visibility: 65 miles, thin smoke layer offshore
6-hr Max temp: 53F
6-hr Min temp: 50F
24-hr Precip: 0.00 ins.
BHO SA 1155 150 SCT 65 233/53/44/2808/022/ THN K LYR OFFSHR/
8/080 52006 10053 20050
10 A.M.
Weather: Scattered cirrostratus
Temperature: 68F; Dew Point: 49F; Wind: W at 7 kts
Sea-level pressure: 30.20 ins. Hg, falling steadily
Visibility: 65 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 250 SCT 65 227/68/49/2807/020/ THN K LYR OFFSHR/
8/008 58006
1 P.M.
Weather: Scattered cirrus
Temperature: 75F; Dew Point: 42F; Wind: W at 5 kts,
Wind: Light
Sea-level pressure: 30.15 ins. Hg, falling
Visibility: 65 miles
6-hr Max temp: 76F
6-hr Min temp: 53F
6-hr Precip: 0.00 ins.
BHO SA 1755 250 SCT 65 211/75/42/2805/015/ WND LGT/ 8/002
56016 10076 20053
SUMMARY FOR THURSDAY, SEPTEMBER 19, 2019
TEMPERATURE (DEGREES F)
MAX…..67 NORMAL…..71
MIN…..43 NORMAL…..54
MEAN….55 NORMAL…..62
DEPARTURE FROM 30-YEAR NORMAL………………….-7
TOTAL DEPARTURE FOR THE MONTH…………………-42 [-2.4 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON AUG TO JUL)
TOTAL HEATING UNITS FOR YESTERDAY…………..10 DEPARTURE………+6
TOTAL HEATING UNITS FOR THE MONTH…………..63 DEPARTURE……..+16
TOTAL HEATING UNITS FOR THE SEASON………….75 DEPARTURE………+3
TOTAL HEATING UNITS LAST SEASON TO DATE……..54 DEPARTURE……..+21
COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0 DEPARTURE………-1
TOTAL COOLING UNITS FOR THE MONTH…………..25 DEPARTURE……..-24
TOTAL COOLING UNITS FOR THE SEASON…………644 DEPARTURE……..+58
TOTAL COOLING UNITS LAST SEASON TO DATE…….849 DEPARTURE…….-211
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..17 NE AT 10:55 P.M.
AERO…………………….18 NE AT 4:12 A.M.
ASOS…………………….17 N AT 4:32 A.M.
DAVIS……………………16 N AT 3:57 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….14 NE AT 4:42 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….14 N AT 5:39 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………14 NNW AT 4:31 A.M.
AVERAGE WIND SPEED AND DIRECTION…………….7.2 ENE
ASOS…………………….7.2
DAVIS……………………7.5 NNE [25 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……….0.98 DEPARTURE……-1.46
ASOS…………..0.96
TOTAL PRECIPITATION FOR THE YEAR……….38.13 DEPARTURE……+0.66
ASOS………….37.99
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
9/01 73/56/65/-3/0.00/…/.. 21 ENE AERO 14 ENE RMY 18
9/02 75/57/66/-2/0.37/…/.. 39 W AERO 41 W RMY 41
9/03 77/61/69/+2/0.00/…/.. 18 S AERO 16 S RMY N/A
9/04 83/61/72/+5/0.00/…/.. 30 SW AERO 28 SW RMY 30
9/05 68/54/61/-6/0.00/…/.. 23 NW AERO 17 NW RMY N/A
9/06 65/56/61/-6/…./…/.. 37 ENE AERO 36 ENE RMY 36
9/07 70/51/61/-5/0.00/…/.. 37 N AERO 37 N RMY N/A
9/08 73/53/63/-3/0.00/…/.. 25 W AERO 21 W RMY N/A
9/09 71/54/63/-3/0.00/…/.. 17 SE AERO 16 SE RMY 16
9/10 73/57/65/0/0.00/…/.. 25 S AERO 25 S RMY N/A
9/11 83/63/73/+8/0.00/…/.. 31 SW AERO 32 SW RMY N/A
9/12 70/52/61/-4/0.11/…/.. 29 ENE AERO 28 ENE RMY 28
9/13 65/49/57/-7/0.00/…/.. 29 ENE AERO 27 ENE RMY 27
9/14 69/49/59/-5/…./…/.. 36 S AERO 37 S RMY 37
9/15 78/62/70/+6/0.00/…/.. 24 W AERO 23 W RMY 22
9/16 72/54/63/0/0.00/…/.. 25 WNW AERO 23 WNW RMY 25
9/17 67/49/58/-5/0.00/…/.. 23 NW AERO 23 N RMY N/A
9/18 61/49/55/-7/0.00/…/.. 26 NE AERO 25 NE RMY 25
9/19 67/43/55/-7/0.00/…/.. 17 NE AERO 18 NE RMY N/A
9/20 The low since midnight is 50F, normal daily minimum 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
