Monday, October 8, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, OCTOBER 8, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

A COOL AND CLOUDY DAY ON TOP OF GREAT BLUE HILL….

Cloudiness persisted throughout the day, with fog arriving
around noon. A shift in wind direction from the southwest to
the northeast is causing cooler than normal temperatures,
with a high so far of only 55F, 8 degrees below our daily
normal of 63F. Our low since midnight, however, was 53F,
which is 7 degrees above our normal low of 46F. Hazy
conditions have reduced visibility to 20 miles all day.

PRELIMINARY STATS FOR SEPTEMBER 2018

TEMPERATURE, Deg. F
Avg. Max. 72.5 [+0.9] Avg. Min. 58.6 [+4.0] Mean 65.6 [+2.5] 24-hour corrected mean: 64.8
Max. for month: 92F on 3rd, 6th
Min. for month: 47F on 23rd

HEATING DEGREE DAYS
Total heating units: 87 [-30] Total for the season: 87 [-55] Total for last season: 93

COOLING DEGREE DAYS
Total cooling units: 110 [+50] Total for the season: 863 [+266] Total for last season: 707

PRECIPITATION, Inches
Total: 9.13 [+5.07] Greatest in 24 hrs: 3.32 ins. on the 18th-19th

WIND, mph
Avg. uncorrected wind speed: N/A
Avg. corrected wind speed: N/A
Prevailing wind direction: N/A
Peak gust and direction: N/A

SUNSHINE:
Campbell-Stokes card minutes: 7608 minutes of possible 21582 or 35%
Astronomical total minutes: 7924 minutes of possible 22447 or 35%

BHO Wettest Septembers, inches (1886-2018):

1) 12.37 in 1999
2) 11.04 in 1933
3) 10.23 in 1896
4) 10.00 in 1961
5) 9.62 in 1987
6) 9.58 in 1888
7) 9.36 in 1918
8) 9.13 in 2018
9) 8.81 in 1907
10) 8.78 in 1996

Today’s Observations:

7 A.M.
Weather: Overcast stratus
Temperature: 53F; Dew Point: 50F; Wind: ENE at 10G19 kts
Sea-level pressure: 30.47 ins. Hg, rising, then more slowly
Visibility: 20 miles, distant haze in all directions
6-hr Max temp: 55F
6-hr Min temp: 53F
24-hr Precip: 0.05 ins.
BHO SA 1155 E12 OVC 20 319/53/50/0710G19/047/ DSNT HZ ALQDS/
8/600 70005 51020 10055 20053

10 A.M.
Weather: Overcast stratus
Temperature: 54F; Dew Point: 50F; Wind: ENE at 8G13 kts
Sea-level pressure: 30.50 ins. Hg, rising, then more slowly
Visibility: 20 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 E16 OVC 20 330/54/50/0708G13/050/ DSNT HZ
ALQDS/ 8/600 51011

1 P.M.
Weather: Overcast stratus
Temperature: 54F; Dew Point: 53F; Wind: ENE at 5G12 kts
Sea-level pressure: 30.48 ins. Hg, falling, then more quickly
Visibility: 20 miles, fog
6-hr Max temp: 55F
6-hr Min temp: 53F
6-hr Precip: 0.01 ins.
BHO SA 1755 E13 OVC 20 323/54/53/0705G12/048/ FOG/ 8/600
60001 58007 10055 20053

SUMMARY FOR SUNDAY, OCTOBER 7, 2018

TEMPERATURE (DEGREES F)
MAX…..75   NORMAL…..63
MIN…..56   NORMAL…..46
MEAN….66   NORMAL…..55

DEPARTURE FROM 30-YEAR NORMAL…………………..11
TOTAL DEPARTURE FOR THE MONTH…………………..22 [+2.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………0   DEPARTURE……..-11
TOTAL HEATING UNITS FOR THE MONTH…………..42   DEPARTURE……..-14
TOTAL HEATING UNITS FOR THE SEASON…………129   DEPARTURE……..-80
TOTAL HEATING UNITS LAST SEASON TO DATE…….121   DIFFERENCE………8

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………1  DEPARTURE……….+1
TOTAL COOLING UNITS FOR THE MONTH……………1  DEPARTURE………..0
TOTAL COOLING UNITS FOR THE SEASON…………864  DEPARTURE……..+264
TOTAL COOLING UNITS LAST SEASON TO DATE…….714  DIFFERENCE…….+150

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..28 NE  AT 3:31 P.M.
AERO…………………….24 ENE AT 3:30 P.M.
ASOS…………………….27 NE  AT 3:32 P.M.
DAVIS……………………20 ENE AT 3:30 P.M. RMY 27
FASTEST MILE FOR YESTERDAY………………….21 ENE AT 4:08 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….21 NE  AT 3:32 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………20 ENE AT 3:51 P.M.
AVERAGE WIND SPEED AND DIRECTION…………..10.4 ENE
ASOS…………………..10.9
DAVIS………………….10.8 S [176 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.15
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.32  DEPARTURE……+0.43
ASOS…………..1.34
TOTAL PRECIPITATION FOR THE YEAR……….48.40  DEPARTURE……+8.61
ASOS………….50.26

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 75/58/67/-1/0.00/521/66        17 NE  AERO 15 NE  RMY 16
9/02 83/61/72/+4/0.00/684/87        20 SSW AERO 18 SSW RMY N/A
9/03 92/68/80/+13/0.00/650/83       24 WSW AERO 22 WSW RMY 25
9/04 88/70/79/+12/0.00/695/89       17 W   AERO 16 W   RMY 17
9/05 89/67/78/+11/0.00/638/82       23 SSW AERO 23 SSW RMY 25
9/06 92/70/81/+14/0.56/488/63       29 NNW AERO 29 NNW RMY N/A TSTM
9/07 70/63/67/+1/0.01/000/00        24 NE  AERO 22 NE  RMY N/A
9/08 68/54/61/-5/0.00/031/04        22 NE  AERO 18 NE  RMY 21
9/09 61/53/57/-9/0.00/000/00        23 NE  AERO 21 NE  RMY N/A
9/10 62/56/59/-6/…./000/00        30 E   AERO 28 E   RMY 28
9/11 75/61/68/+3/…./000/00        23 E   AERO 21 E   RMY N/A TSTM
9/12 69/63/66/+1/…./000/00        21 ENE AERO 21 ENE RMY 21  TSTM
9/13 68/62/65/+1/…./091/12        21 NE  AERO 21 NE  RMY N/A TSTM
9/14 75/61/68/+4/…./233/31        13 NE  AERO 12 ENE RMY 12
9/15 76/62/69/+5/0.01/218/29        14 SW  AERO 13 SW  RMY 13
9/16 84/61/73/+10/…./695/93       15 S   AERO 14 S   RMY N/A
9/17 82/64/73/+10/…./372/50       22 SSW AERO 22 SSW RMY N/A
9/18 74/67/71/+9/…./000/00        31 SSW AERO 30 SSW RMY N/A TSTM
9/19 66/57/62/0/…./007/01         28 NE  AERO 25 NE  RMY 26
9/20 63/55/59/-3/…./110/15        22 NE  AERO 21 NE  RMY 19
9/21 70/55/63/+2/…./352/48        37 SSW AERO 37 SSW RMY 41
9/22 70/51/61/0/…./175/24         37 SW  AERO 36 SW  RMY 30
9/23 60/47/54/-6/…./058/08        14 N   AERO 13 N   RMY N/A
9/24 55/50/53/-7/…./000/00        37 ENE AERO 35 ENE RMY 35
9/25 68/51/60/0/…./000/00         36 SE  AERO 37 SE  RMY 38
9/26 79/66/73/+14/…./244/34       35 SSW AERO 37 SSW RMY 37
9/27 66/56/61/+2/…./465/65        26 NNE AERO 25 NNE RMY 28
9/28 56/52/54/-4/…./029/04        24 NNE AERO 21 NNE RMY 23
9/29 71/50/61/+3/…./518/73        20 NW  AERO 18 NW  RMY 20
9/30 68/48/58/0/…./650/92         20 W   AERO 16 W   RMY N/A

DAILY RECORDS FOR SEPTEMBER

09/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F,
BREAKS PREVIOUS RECORD OF 68F SET IN 1937 AND 1959

09/06/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 92F,
TIES PREVIOUS RECORD OF 92F SET IN 1900

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

10/1 65/53/59/+2/…./…/..        21 ENE AERO 18 SSW RMY N/A
10/2 64/53/59/+2/…./…/..        33 S   AERO 32 S   RMY 35 TSTM
10/3 60/52/56/0/…./…/..          18 NNE AERO 14 NNE RMY 14
10/4 69/57/63/+7/…./…/..        29 SSW AERO 29 SSW RMY 32
10/5 64/47/56/0/…./…/..          25 NE  AERO 21 NE  RMY 24
10/6 64/45/55/0/0.00/…/..       23 SSW AERO 23 SSW RMY 25
10/7 75/56/66/+11/…./…/..      28 NE  AERO 24 ENE RMY 27

10/8 Low temp since midnight is 53F; normal low is now 46F

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

RECORDS FOR OCTOBER 8
HIGH 81F IN 1916,1990
LOW 28F IN 1919
PRECIP 2.31 INCHES IN 1891
SNOWFALL TRACE IN 1988, 2001 (EARLIEST DATE)
PEAK GUST 60 MPH NE IN 1996

RECORDS FOR OCTOBER 9
HIGH 82F IN 2011
LOW 29F IN 1907,1937
PRECIP 2.54 INCHES IN 1976
SNOWFALL 0.2 INCHES IN 1888
PEAK GUST 81e MPH S IN 1976 (RECORD FOR MONTH)

TODAY’S REPORT PREPARED BY: Samantha Richard