Saturday, October 17, 2020
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
SATURDAY, OCTOBER 17, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME
OCTOBER PROVIDES A RELIEF FROM THE OVERWHELMING
RAINFALL DEFICIT….
During and after the frontal passage yesterday, a whole
2.21 inches of rain fell from yesterday to this morning.
A light rain continued between 7 A.M. and 9 A.M, giving
us an event total of 2.24 inches! This makes a dent in
the annual rainfall deficit, making us less than 3 inches
below normal. The monthly rainfall departure is now at
a surplus of 1.74 inches.
Following the rain and fog in the morning, visibility
opened up to over 70 miles, and skies have become
partly cloudy. Wind is on the strong side today due
to the quick change in pressure of over 6 millibars since
this morning. Wind is north-westerly at an average
of 20 mph, and the highest gust is 37 mph as of yet.
The high so far today is 55F, 5 degrees below the daily
normal of 60F. The low since midnight is 39F, 3 degrees
below the normal low of 42F.
PRELIMINARY STATS FOR SEPTEMBER 2020
TEMPERATURE, Deg. F
Avg. Max. 73.2 [+1.6]
Avg. Min. 54.9 [+0.3]
Mean 64.1 [+1.0]
24-hour corrected mean: 63.6
Max. for month: 82F on the 8th
Min. for month: 39F on the 22nd
HEATING DEGREE DAYS
Total heating units: 95 [-22]
Total for the season: 98 [-44]
Total for last season: 93
COOLING DEGREE DAYS
Total cooling units: 73 [+13]
Total for the season: 830 [+233]
Total for last season: 680
PRECIPITATION, Inches
Total: 1.61 [-2.45]
Greatest in 24 hrs: 1.02 ins. on 29th-30th
WIND, mph
Avg. uncorrected wind speed: 10.6 mph
Avg. corrected wind speed: 11.1 mph
Prevailing wind direction: S [20%]
Peak gust and direction: 71 S on the 30th
SUNSHINE:
Campbell-Stokes card minutes: 12150 minutes of a possible 21582 or 56%
Astronomical total minutes: 12593 minutes of a possible 22403 or 56%
Today’s Observations:
7 A.M.
Weather: Overcast nimbostratus, light rain
Temperature: 40F; Dew Point: 40F; Relative Humidity: 100%
Wind: NW at 13G21 kts
Sea-level pressure: 30.08 ins. Hg: rising then falling
Visibility: 4 miles ( fog)
6-hr Max temp: 46F
6-hr Min temp: 40F
24-hr Precip: 2.21 ins.
BHO SA 1155 E80 OVC 4R-F 185/40/40/3313G21/008/ R-CTD/ 8/02/ 70221
50002 10046 20040
10 A.M.
Weather: Broken cumulus and altocumulus
Temperature: 44F; Dew Point: 41F; Relative Humidity: 88%
Wind: WNW at 11G24 kts
Sea-level pressure: 30.17 ins. Hg: rising rapidly
Visibility: 70 miles
3-hr Precip: 0.03 ins.
BHO SA 1455 30 BKN 70 BKN 70 214/44/41/3011G24/017/ 8/170
6003/ 53029
1 P.M.
Weather: Scattered cumulus
Temperature: 54F; Dew Point: 38F; Relative Humidity: 53%
Wind: WNW at 12G22 kts, peak of 35 mph at 12:16 P.M.
Sea-level pressure: 30.22 ins. Hg: rising steadily
Visibility: 75 miles
6-hr Max temp: 55F
6-hr Min temp: 39F
6-hr Precip: 0.03 inches
BHO SA 1755 30 SCT 75 230/54/38/3012G22/022/ PK WND 3030/16/ 8/100 6003/
51016 10055 20039
SUMMARY FOR FRIDAY, OCTOBER 16, 2020
TEMPERATURE (DEGREES F)
MAX…..68 NORMAL…..60
MIN…..48 NORMAL…..43
MEAN….58 NORMAL…..51
DEPARTURE FROM 30-YEAR NORMAL……………..+7
TOTAL DEPARTURE FOR THE MONTH…………….+43 [+2.5 DEGREES/DAY]
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..7 DEPARTURE….. -7
TOTAL HEATING UNITS FOR THE MONTH…………130 DEPARTURE…..-48
TOTAL HEATING UNITS FOR THE SEASON………..228 DEPARTURE…..-92
TOTAL HEATING UNITS LAST SEASON TO DATE……264 DEPARTURE…..-36
COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………. 0 DEPARTURE…… 0
TOTAL COOLING UNITS FOR THE MONTH…………. 1 DEPARTURE….. -4
TOTAL COOLING UNITS FOR THE SEASON………..831 DEPARTURE….+229
TOTAL COOLING UNITS LAST SEASON TO DATE……682 DEPARTURE….+149
PEAK WIND GUST FOR YESTERDAY (MPH)
420C/Official……………28 S AT 1:02 A.M.
AEROVANE (south tower)……30 S AT 12:17 A.M.
ASOS……………………31 S AT 12:58 A.M.
DAVIS #1………………..31 S AT 12:58 A.M.
DAVIS #2 (south tower)……33 N AT 2:34 A.M.
RMY…………………….34
MERLIN………………….33
FASTEST MILE FOR YESTERDAY…………………24 NNW AT 12:34 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………24 S AT 1:05 A.M.
MAXIMUM 2-MINUTE DAVIS #1 AVERAGE…………..23 NNW AT 12:33 A.M.
MAXIMUM 2-MINUTE DAVIS #2 AVERAGE…………..26 S AT 1:05 A.M.
AVERAGE WIND SPEED AND DIRECTION………….12.8 S [307 total miles]
ASOS………………….12.8
DAVIS #1………………12.3 WSW [248 deg.]
DAVIS #2………………13.8 SSW [204 deg.]
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….2.21 DEPARTURE….+2.06
ASOS…………..2.19
TOTAL PRECIPITATION FOR THE MONTH……….4.11 DEPARTURE….+1.74
ASOS…………..4.10
TOTAL PRECIPITATION FOR THE YEAR……….38.53 DEPARTURE….-2.92
ASOS………….39.31
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 76/59/68/0/0.00/698/88 22 SSE AERO 21 SE RMY 20
09/02 69/59/64/-4/0.18/102/13 23 SSE AERO 23 SSE RMY 24
09/03 75/66/71/+4/0.04/000/00 22 SSW AERO 21 SSW RMY N/A
09/04 82/62/72/+5/0.00/763/98 26 WNW AERO 26 WNW RMY 25
09/05 76/55/66/-1/0.00/760/98 25 W AERO 25 W RMY 24
09/06 78/58/68/+1/0.00/356/46 24 W AERO 24 W RMY N/A
09/07 79/61/70/+4/0.00/632/82 27 SSE AERO 30 SSE RMY 28
09/08 82/61/72/+6/0.00/545/71 17 S AERO 16 S RMY 17
09/09 80/62/71/+5/0.00/214/28 16 S AERO 15 S RMY 16
09/10 81/69/75/+10/0.28/015/02 21 SSW AERO 21 SSW RMY N/A
09/11 72/55/64/-1/0.01/152/20 25 N AERO 25 N RMY N/A
09/12 68/51/60/-5/0.00/666/88 21 ENE AERO 21 ENE RMY 21
09/13 74/53/64/0/0.00/611/81 26 SSW AERO 26 SSW RMY 26
09/14 74/50/62/-2/0.00/511/68 29 NNW AERO 33 NNW RMY 30
09/15 64/44/54/-10/0.00/583/78 18 S AERO 18 S RMY N/A
09/16 72/49/61/-2/0.00/603/81 31 SSW AERO 31 SSW RMY 31
09/17 76/57/67/+4/0.00/453/61 26 WSW AERO 28 W RMY N/A
09/18 64/48/56/-6/0.00/163/22 28 NE AERO 30 NNW RMY N/A
09/19 59/42/51/-11/0.00/722/98 23 N AERO 23 N RMY N/A
09/20 58/40/49/-13/0.00/602/82 25 NE AERO 25 NE RMY 27
09/21 61/41/51/-10/0.00/694/95 29 NE AERO 27 NE RMY 29
09/22 63/39/51/-10/0.00/022/03 28 NNW AERO 30 NNW RMY 29
09/23 78/50/64/+4/0.00/617/85 31 NW AERO 32 WNW RMY 32
09/24 76/57/67/+7/0.00/347/48 20 SW AERO 18 WSW RMY 19
09/25 77/57/67/+7/0.00/655/91 18 ENE AERO 18 WSW RMY N/A
09/26 77/57/67/+8/0.00/516/72 21 S AERO 21 S RMY 21
09/27 79/64/72/+13/0.01/121/17 24 S AERO 25 S RMY 24
09/28 78/64/71/+13/0.07/199/28 24 SSE AERO 24 S RMY 25
09/29 76/62/69/+11/0.01/234/33 30 S AERO 30 S RMY N/A
09/30 72/56/64/+6/1.01/395/56 71 S AERO 88 S RMY N/A
PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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
10/01 75/56/66/+9/0.00/…/.. 28 SW AERO 28 SW RMY N/A
10/02 63/49/56/-1/0.02/…/.. 20 NW AERO 21 NW RMY 20
10/03 65/45/55/-1/0.00/…/.. 19 WNW AERO 19 WNW RMY 19
10/04 65/45/55/-1/0.00/…/.. 17 ESE AERO 18 ESE RMY 18
10/05 62/52/57/+1/0.00/…/.. 17 ENE AERO 17 ENE RMY N/A
10/06 69/51/60/+5/0.00/…/.. 28 S AERO 28 S RMY 29
10/07 73/50/62/+7/0.14/…/.. 76 W AERO 74 W RMY 70 TSTM
10/08 61/42/52/-2/0.00/…/.. 41 W AERO 41 W RMY N/A
10/09 60/37/49/-5/0.00/…/.. 25 SSW AERO 28 SSW RMY N/A
10/10 75/52/64/+10/0.00/…/.. 40 SSW AERO 40 SSW RMY 38
10/11 64/47/56/+3/0.00/…/.. 32 NNW AERO 35 NNW RMY N/A
10/12 52/48/50/-3/T/…/.. 28 E AERO 27 E RMY N/A
10/13 57/49/53/0/1.74/…/.. 32 E AERO 33 E RMY N/A
10/14 67/47/57/+5/0.00/…/.. 23 WNW AERO 25 WNW RMY N/A
10/15 71/50/61/+9/0.00/…/.. 43 S AERO 46 S RMY 42
10/16 68/48/58/+7/…./…/.. 28 S AERO 30 S RMY N/A
10/17 The low since midnight is 40F, the daily normal low is 42F
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
RECORDS FOR OCTOBER 17
HIGH 86F IN 1947
LOW 25F IN 1886
PRECIP 1.87 INCHES IN 1989
SNOWFALL TRACE IN 1970
PEAK GUST 61 MPH E IN 2019
RECORDS FOR OCTOBER 18
HIGH 82F IN 1908
LOW 26F IN 1939
PRECIP 2.79 INCHES IN 1975
SNOWFALL 3.0 INCHES IN 2009
PEAK GUST 66 MPH S IN 1967
TODAY’S REPORT PREPARED BY: Benjamin Turner
