Sunday, October 13, 2019

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, OCTOBER 13, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

FAIR WEATHER FOLLOWING A RAINY STRETCH
ATOP GREAT BLUE HILL….

We observed a great visibility of 80 miles throughout
the day, with partly cloudy skies and a light westerly
breeze. Today started humid, but dried out as dew points
held in the low 50’s with increasing temperature.

Rainfall over the last four days has brought us back to
normal in regards to annual rainfall. We are now 0.21
inches above the yearly normal amount following two
very dry months.

The high so far today is 65F, 4 degrees above the daily
normal maximum of 61F. The low since midnight is 48F,
4 degrees above the normal minimum of 44F.

PRELIMINARY STATS FOR SEPTEMBER 2019

TEMPERATURE, Deg. F
Avg. Max. 73.6 [+2.0] Avg. Min. 54.5 [-0.1] Mean      64.1 [+1.0] 24-hour corrected mean: 63.4
Max. for month: 88F on the 23rd
Min. for month: 43F on the 19th

HEATING DEGREE DAYS
Total heating units:    81 [-36] Total for the season:   93 [-49] Total for last season:  87

COOLING DEGREE DAYS
Total cooling units:    58  [-2] Total for the season:  680 [+83] Total for last season: 863

PRECIPITATION, Inches
Total: 1.27 [-2.79] Greatest in 24 hrs: 0.37 ins. on the 2nd

WIND, mph
Avg. uncorrected wind speed: 10.3 mph
Avg. corrected wind speed:   10.9 mph
Prevailing wind direction:   SSW [11%] Peak gust and direction:     39 W on the 2nd

SUNSHINE:
Campbell-Stokes card minutes: 14790 minutes of possible 21582 or 69%
Astronomical total minutes: 15399 minutes of possible 22468 or 69%

Today’s Observations:

7 A.M.
Weather: Scattered stratocumulus, broken cirrus
Temperature: 50F; Dew Point: 50F; Wind: WNW at 9 kts
Sea-level pressure: 30.05 ins. Hg, increasing steadily
Visibility: 80 miles
6-hr Max temp: 50F
6-hr Min temp: 48F
24-hr Precip: 0.10 ins.
BHO SA 1155 40 SCT E250 BKN 80 176/50/50/3009/005/
8/402 70010 53017 10050 20048

10 A.M.
Weather: Scattered stratocumulus, broken cirrus
Temperature: 57F; Dew Point: 52F; Wind: NW at 8 kts
Sea-level pressure: 30.09 ins. Hg, rising
Visibility: 80 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 50 SCT E250 BKN 80 187/57/52/3208/009/
8/402 51011

1 P.M.
Weather: Scattered cumulus, broken cirrus
Temperature: 64F; Dew Point: 50F; Wind: W at 3 kts,
Wind: Light and variable
Sea-level pressure: 30.08 ins. Hg, rising then falling
Visibility: 80 miles
6-hr Max temp: 65F
6-hr Min temp: 50F
6-hr Precip: 0.00 ins.
BHO SA 1755 50 SCT E250 BKN 80 183/64/50/2803/008/ WND L/V/
8/402 58004 10065 20050

SUMMARY FOR SATURDAY, OCTOBER 12, 2019

TEMPERATURE (DEGREES F)
MAX…..52   NORMAL…..62
MIN…..49   NORMAL…..44
MEAN….51   NORMAL…..53

DEPARTURE FROM 30-YEAR NORMAL………………….-2
TOTAL DEPARTURE FOR THE MONTH…………………-10 [-1.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………14  DEPARTURE………+2
TOTAL HEATING UNITS FOR THE MONTH…………..132  DEPARTURE…….. +7
TOTAL HEATING UNITS FOR THE SEASON………….255  DEPARTURE……..-42
TOTAL HEATING UNITS LAST SEASON TO DATE……..154  DEPARTURE……..+71

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………….0  DEPARTURE……….0
TOTAL COOLING UNITS FOR THE MONTH…………….2  DEPARTURE………-2
TOTAL COOLING UNITS FOR THE SEASON………….682  DEPARTURE……..+81
TOTAL COOLING UNITS LAST SEASON TO DATE……..874  DEPARTURE…….-192

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..39 NE  AT 12:13 A.M.
AERO…………………….37 NE  AT 12:15 A.M.
ASOS…………………….39 NNE AT 12:15 A.M.
DAVIS……………………37 NE  AT 12:05 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….25 NE  AT 12:52 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….24 NE  AT  1:19 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………25 NE  AT 12:13 A.M.
AVERAGE WIND SPEED AND DIRECTION……………..9.5 NNE
ASOS……………………..9.3
DAVIS…………………….9.5 NNE [34 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.10  DEPARTURE……-0.05
ASOS…………..0.11
TOTAL PRECIPITATION FOR THE MONTH……….2.66  DEPARTURE……+0.88
ASOS…………..2.76
TOTAL PRECIPITATION FOR THE YEAR……….41.08  DEPARTURE……+0.21
ASOS………….40.99

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/-3/0.00/703/89                21 ENE AERO 14 ENE RMY 18
9/02  75/57/66/-2/0.37/165/21                39 W   AERO 41 W   RMY 41
9/03  77/61/69/+2/0.00/643/82                18 S   AERO 16 S   RMY N/A
9/04  83/61/72/+5/0.00/375/48                30 SW  AERO 28 SW  RMY 30
9/05  68/54/61/-6/0.00/513/66                23 NW  AERO 17 NW  RMY N/A
9/06  65/56/61/-6/0.03/054/07                37 ENE AERO 36 ENE RMY 36
9/07  70/51/61/-5/0.27/325/42                37 N   AERO 37 N   RMY N/A
9/08  73/53/63/-3/0.00/631/82                25 W   AERO 21 W   RMY N/A
9/09  71/54/63/-3/0.00/537/70                17 SE  AERO 16 SE  RMY 16
9/10  73/57/65/0/0.00/207/27                 25 S   AERO 25 S   RMY N/A
9/11  83/63/73/+8/0.00/419/55                31 SW  AERO 32 SW  RMY N/A
9/12  70/52/61/-4/0.11/015/02                29 ENE AERO 28 ENE RMY 28
9/13  65/49/57/-7/0.00/741/98                29 ENE AERO 27 ENE RMY 27
9/14  69/49/59/-5/0.19/030/04                36 S   AERO 37 S   RMY 37
9/15  78/62/70/+6/0.00/600/80                24 W   AERO 23 W   RMY 22
9/16  72/54/63/0/T/673/90                    25 WNW AERO 23 WNW RMY 25
9/17  67/49/58/-5/0.00/611/82                23 NW  AERO 23 N   RMY N/A
9/18  61/49/55/-7/0.00/579/78                26 NE  AERO 25 NE  RMY 25
9/19  67/43/55/-7/0.00/709/96                17 NE  AERO 18 NE  RMY N/A
9/20  78/50/64/+2/0.00/677/92                21 W   AERO 18 W   RMY 20
9/21  83/60/72/+11/0.00/689/94               21 WNW AERO 18 WNW RMY N/A
9/22  85/62/74/+13/0.00/687/94               24 SW  AERO 23 SW  RMY 25
9/23  88/65/77/+17/0.00/539/74               29 SSW AERO 28 SSW RMY 29
9/24  76/56/66/+6/0.04/616/85                26 W   AERO 26 W   RMY 27
9/25  73/50/62/+2/0.00/686/95                22 W   AERO 21 W   RMY 21
9/26  79/55/67/+8/0.25/388/54                38 SW  AERO 37 SW  RMY 39
9/27  72/50/61/+2/0.00/695/97                23 S   AERO 23 S   RMY 22
9/28  78/55/67/+9/0.00/664/93                31 S   AERO 29 S   RMY 30
9/29  75/53/64/+6/0.00/619/87                24 NW  AERO 23 NW  RMY 23
9/30  62/49/56/-2/0.00/609/86                23 NNE AERO 16 NNE 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  67/52/60/+3/0.06/…/..               28 SW  AERO 25 SSW RMY 29
10/02  74/49/62/+5/0.42/…/..               30 ENE AERO 25 ENE RMY 28
10/03  51/46/49/-7/…./…/..               28 ENE AERO 26 ENE RMY N/A
10/04  59/40/50/-6/…./…/..               38 NNW AERO 38 NNW RMY 38
10/05  58/35/47/-9/0.00/…/..               21 N   AERO 18 SSW RMY N/A
10/06  65/44/55/0/0.00/…/..                36 SSW AERO 35 SSW RMY N/A
10/07  77/57/67/+12/0.12/…/..              47 SSW AERO 46 SSW RMY 49
10/08  60/52/56/+2/T/…/..                  22 NE  AERO 18 NW  RMY N/A
10/09  55/49/52/-2/…./…/..               43 NE  AERO 37 NE  RMY 44
10/10  54/47/51/-3/…./…/.. 41 NE  AERO 37 NE  RMY 42
10/11  52/48/50/-3/…./000/00               41 NE  AERO 39 NE  RMY 41
10/12  52/49/51/-2/…./…/..               39 NE  AERO 37 NE  RMY N/A

10/13 The low since midnight is 48F, normal daily minimum is 44F

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

RECORDS FOR OCTOBER 13
HIGH 84F IN 1930,1954
LOW 29F IN 2012
PRECIP 5.92 INCHES IN 1895
SNOWFALL 4.2 INCHES IN 1934
PEAK GUST 46e MPH W IN 1950

RECORDS FOR OCTOBER 14
HIGH 79F IN 2000
LOW 28F IN 1958
PRECIP 2.69 INCHES IN 1990
SNOWFALL 2.0 INCHES IN 1913
PEAK GUST 63e W IN 1976

TODAY’S REPORT PREPARED BY: Benjamin Turner