Friday, October 4, 2019

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, OCTOBER 4, 2019
ALL TIMES ARE IN EASTERN STANDARD TIME

A NICE FALL DAY AFTER THIS MORNING’S FOG
ATOP GREAT BLUE HILL….

We observed a visibility of a 1/16th mile this morning,
due to fog associated with last night’s rainfall. We
measured 0.11 inches at the 7 A.M. observation. The
fog dissipated by the 10 A.M., where an excellent
visibility of 85 miles was observed. It has been blustery
today, with a max gust of 39 mph being observed. A wind
shift from W to NNW was seen later on this morning.

Partly cloudy skies accompanied with cold air advection
from the north and west have kept temperatures below
seasonal averages. The high so far today is 59F, which
is 7 degrees below the normal high of 65F. The low this
morning was 47F, which is the same as the daily normal
minimum.

PRELIMINARY STATS FOR SEPTEMBER 2019

TEMPERATURE, Deg. F
Avg. Max. 73.6 [+2.0] Avg. Min. 54.5 [-0.1] Mean      61.4 [-1.7] 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: N/A

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: N/A
Astronomical total minutes:   N/A

Today’s Observations:

7 A.M.
Weather: Fog
Temperature: 48F; Dew Point: 48F; Wind: W at 9 kts
Sea-level pressure: 29.90 ins. Hg, falling then rising
Visibility: 1/16 mile, fog
6-hr Max temp: 48F
6-hr Min temp: 48F
24-hr Precip: 0.11 ins.
BHO SA 1155 X W3 1/16F 125/48/48/2809/990/ 8////
70011 53001 10048 20048

10 A.M.
Weather: Broken stratocumulus
Temperature: 56F; Dew Point: 46F; Wind: NNW at 14G27 kts,
Peak wind: 38 MPH (33 kts) at 9:32 A.M.
Sea-level pressure: 29.96 ins. Hg, rising steadily
Visibility: 85 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 E30 BKN 85 147/56/46/3414G27/996/ PK WND
3433/32/ 8/800 53022

1 P.M.
Weather: Broken stratocumulus
Temperature: 57F; Dew Point: 42F; Wind: NNW at 10G20 kts,
Peak wind: 38 MPH (33 kts) at 10:23 A.M.
Sea-level pressure: 30.03 ins. Hg, rising, then more
rapidly
Visibility: 85 miles
6-hr Max temp: 59F
6-hr Min temp: 48F
6-hr Precip: 0.00 ins.
BHO SA 1755 E40 BKN 85 171/57/42/3410G20/003/ PK WND
3433/1523/ 8/800 51024 10059 20048

SUMMARY FOR THURSDAY, OCTOBER 3, 2019

TEMPERATURE (DEGREES F)
MAX…..51   NORMAL…..65
MIN…..46   NORMAL…..48
MEAN….49   NORMAL…..56

DEPARTURE FROM 30-YEAR NORMAL………………….-7
TOTAL DEPARTURE FOR THE MONTH………………….+1 [+0.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..16   DEPARTURE………+7
TOTAL HEATING UNITS FOR THE MONTH…………..24   DEPARTURE………-2
TOTAL HEATING UNITS FOR THE SEASON…………117   DEPARTURE……..-52
TOTAL HEATING UNITS LAST SEASON TO DATE…….108   DEPARTURE………+9

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0   DEPARTURE……….0
TOTAL COOLING UNITS FOR THE MONTH……………0   DEPARTURE………-1
TOTAL COOLING UNITS FOR THE SEASON…………680   DEPARTURE……..+83
TOTAL COOLING UNITS LAST SEASON TO DATE…….863   DEPARTURE…….-183

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..28 ENE  AT 12:41 A.M.
AERO…………………….26 ENE  AT  4:14 A.M.
ASOS…………………….27 NE   AT  5:09 A.M.
DAVIS……………………27 NE   AT  5:07 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………….18 ENE  AT  4:45 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….18 ENE  AT  8:39 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………19 ENE  AT  4:43 A.M.
AVERAGE WIND SPEED AND DIRECTION…………….9.1 ESE
ASOS…………………….9.1
DAVIS……………………9.7 E [87 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.11  DEPARTURE……-0.03
ASOS…………..0.11
TOTAL PRECIPITATION FOR THE MONTH……….0.59  DEPARTURE……+0.14
ASOS…………..0.58
TOTAL PRECIPITATION FOR THE YEAR……….39.01  DEPARTURE……-0.53
ASOS………….38.81

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/…/..                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  78/50/64/+2/0.00/…/..                21 W   AERO 18 W   RMY 20
9/21  83/60/72/+11/0.00/…/..               21 WNW AERO 18 WNW RMY N/A
9/22  85/62/74/+13/0.00/…/..               24 SW  AERO 23 SW  RMY 25
9/23  88/65/77/+17/0.00/…/..               29 SSW AERO 28 SSW RMY 29
9/24  76/56/66/+6/0.04/…/..                26 W   AERO 26 W   RMY 27
9/25  73/50/62/+2/0.00/…/..                22 W   AERO 21 W   RMY 21
9/26  79/55/67/+8/0.25/…/..                38 SW  AERO 37 SW  RMY 39
9/27  72/50/61/+2/0.00/…/..                23 S   AERO 23 S   RMY 22
9/28  78/55/67/+9/0.00/…/..                31 S   AERO 29 S   RMY 30
9/29  75/53/64/+6/0.00/…/..                24 NW  AERO 23 NW  RMY 23
9/30  62/49/56/-2/0.00/…/..                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  The low since midnight is 47F, normal daily minimum is 47F

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

RECORDS FOR OCTOBER 4
HIGH 84F IN 2007
LOW 28F IN 1888
PRECIP 1.87 INCHES IN 2011
PEAK GUST 59 MPH SSW IN 1990

RECORDS FOR OCTOBER 5
HIGH 86F IN 2007
LOW 29F IN 1965
PRECIP 3.17 INCHES IN 1962
PEAK GUST 64e MPH S IN 1979

TODAY’S REPORT PREPARED BY: Benjamin Turner and Ann Murphy