Saturday, October 6, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, OCTOBER 6, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

NORMAL TEMPERATURES WITH AN INCREASE IN CLOUD COVER AS
THE DAY PROGRESSED….
Today started with a fairly clear sky, with only a few
stratocumulus clouds obscuring about 2/8ths of the sky.
Pressure began to drop around 8:00 A.M., leading to an
increase in cloud cover, with 7/8ths of the sky being
covered by stratocumulus clouds by the 10:00 A.M.
observation. Visibility remained steady through the day
around 70 miles, with some distant haze limiting further
visibility. So far today we have reached a maximum
temperature of 64F, the same as our normal maximum
temperature. Our low since midnight was 45F, 2 degrees
below our normal low temperature of 47F.
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: N/A
Astronomical total minutes: N/A

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: Clear, few stratocumulus in all directions
Temperature: 51F; Dew Point: 44F; Wind: NE at 4 kts
Wind: light
Sea-level pressure: 30.24 ins. Hg, rising, then more slowly
Visibility: 70 miles, distant haze in all directions
6-hr Max temp: 51F
6-hr Min temp: 45F
24-hr Precip: 0.00 ins.
BHO SA 1155 CLR 70 240/51/44/0504/024/ FEW SC ALQDS DSNT HZ
ALQDS WND LGT/ 8/500 51014 10051 20045

10 A.M.
Weather: Broken stratocumulus, few cumulus in all directions
Temperature: 56F; Dew Point: 47F; Wind: W at 5 kts
Wind: Light and variable
Sea-level pressure: 30.24 ins. Hg, rising then falling
Visibility: 70 miles, distant haze in all directions
3-hr Precip: 0.00 ins.
BHO SA 1455 E37 BKN 70 244/56/47/E2705/024/ FEW CU ALQDS
DSNT HZ ALQDS WND L/V/ 8/500 50004

1 P.M.
Weather: Scattered stratocumulus
Temperature: 64F; Dew Point: 50F; Wind: S at 2 kts
Wind: light
Sea-level pressure: 30.22 ins. Hg, falling then rising
Visibility: 70 miles distant haze in all directions
6-hr Max temp: 64F
6-hr Min temp: 51F
6-hr Precip: 0.00 ins.
BHO SA 1755 30 SCT 70 234/64/50/1803/022/ DSNT HZ ALQDS
WND LGT/ 8/500 10064 20051

SUMMARY FOR FRIDAY, OCTOBER 5, 2018

TEMPERATURE (DEGREES F)
MAX…..64   NORMAL…..65
MIN…..47   NORMAL…..47
MEAN….56   NORMAL…..56

DEPARTURE FROM 30-YEAR NORMAL……………………0
TOTAL DEPARTURE FOR THE MONTH…………………..11 [+2.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………9   DEPARTURE………-1
TOTAL HEATING UNITS FOR THE MONTH…………..32   DEPARTURE……..-12
TOTAL HEATING UNITS FOR THE SEASON…………119   DEPARTURE……..-69
TOTAL HEATING UNITS LAST SEASON TO DATE…….121   DIFFERENCE……..-2

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0  DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE MONTH……………0  DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE SEASON…………863  DEPARTURE……..+264
TOTAL COOLING UNITS LAST SEASON TO DATE…….712  DIFFERENCE…….+151

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..25 NE  AT 8:00  A.M.
AERO…………………….21 NE  AT 8:08  A.M.
ASOS…………………….26 NNW AT 1:27  A.M.
DAVIS……………………25 N   AT 1:31  A.M. RMY 24
FASTEST MILE FOR YESTERDAY………………….17 NE  AT 10:08 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….17 NE  AT 1:22  A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………18 NNW AT 1:32  A.M.
AVERAGE WIND SPEED AND DIRECTION……………10.4 NE
ASOS……………………10.2
DAVIS…………………..10.8 NE [53 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……….1.34  DEPARTURE……+0.58
ASOS…………..1.34
TOTAL PRECIPITATION FOR THE YEAR……….48.40  DEPARTURE……+8.90
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/…./…/..        22 NE  AERO 21 NE  RMY 19
9/21 70/55/63/+2/…./…/..        37 SSW AERO 37 SSW RMY 41
9/22 70/51/61/0/…./…/..         37 SW  AERO 36 SW  RMY 30
9/23 60/47/54/-6/…./…/..        14 N   AERO 13 N   RMY N/A
9/24 55/50/53/-7/…./…/..        37 ENE AERO 35 ENE RMY 35
9/25 68/51/60/0/…./…/..         36 SE  AERO 37 SE  RMY 38
9/26 79/66/73/+14/…./…/..       35 SSW AERO 37 SSW RMY 37
9/27 66/56/61/+2/…./…/..        26 NNE AERO 25 NNE RMY 28
9/28 56/52/54/-4/…./…/..        24 NNE AERO 21 NNE RMY 23
9/29 71/50/61/+3/…./…/..        20 NW  AERO 18 NW  RMY 20
9/30 68/48/58/0/…./…/..         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 58/47/53/-3/…./…/..         25 NE  AERO 21 NE  RMY 24

10/6 Low temp since midnight is 45F; normal low is now 47F

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

RECORDS FOR OCTOBER 6
HIGH 83F IN 1990, 2007
LOW 26F IN 1965
PRECIP 3.78 INCHES IN 1962
PEAK GUST 60e MPH S IN 1942

RECORDS FOR OCTOBER 7
HIGH 88F IN 1963 (RECORD FOR MONTH)
LOW 30F IN 1904,1986
PRECIP 1.75 INCHES IN 1972
PEAK GUST 54 W IN 2009

TODAY’S REPORT PREPARED BY: Samantha Richard