Thursday, October 4, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, OCTOBER 4, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

ABOVE SEASONABLE DAY WITH FAIR WEATHER ATOP GREAT BLUE HILL….
SEPTEMBER FINISHES AS THE EIGHTH WETTEST ON RECORD…

Fog this morning cleared quickly after the 7 A.M. observation,
increasing visibility from a 1/2 mile to 40 miles by 10 A.M.
Wind increased after noontime, frequently blowing over 20 mph from
the south. A pressure drop of 3 millibars occurred between the
10 A.M. and 1 P.M. observations. Temperatures increased to 68F
so far today, 3 degrees above the daily normal of 65F. The low
since midnight is 55F, 8 degrees above the normal minimum of 47F.

PRELIMINARY STATS FOR SEPTEMBER 2018

TEMPERATURE, Deg. F
Avg. Max. 72.5 [+0.9] Avg. Min. 58.6 [+4.0] Mean 65.8 [+2.7] 24-hour corrected mean: 65.6
Max. for month: 92F on 3rd
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: Fog
Temperature: 57F; Dew Point: 57F; Wind: N at 8G14 kts
Sea-level pressure: 30.35 ins. Hg, rising then falling
Visibility: 1/2 mile, fog
6-hr Max temp: 57F
6-hr Min temp: 55F
24-hr Precip: 0.01 ins.
BHO SA 1155 W3 X 1/2F 278/57/57/1808G14/035/ 8//// 70001
55000 10057 20055

10 A.M.
Weather: Broken cumulus, overcast cirrus
Temperature: 65F; Dew Point: 60F; Wind: S at 11G18 kts
Sea-level pressure: 30.32 ins. Hg, falling, then more rapidly
Visibility: 40 miles, distant fog
3-hr Precip: 0.00 ins.
BHO SA 1455 E20 BKN 200 OVC 40 268/65/60/1911G18/032/
DSNT FG ALQDS/ 8/202 58010

1 P.M.
Weather: Overcast stratocumulus
Temperature: 68F; Dew Point: 62F; Wind: S at 17G24 kts
Sea-level pressure: 30.23 ins. Hg, falling rapidly
Visibility: 40 miles, distant haze
6-hr Max temp: 68F
6-hr Min temp: 57F
6-hr Precip: 0.00 ins.
BHO SA 1755 E20 OVC 40 238/68/62/1817G24/023/ DSNT HZ ALQDS/
8/4// 58030 10068 20057

SUMMARY FOR WEDNESDAY, OCTOBER 3, 2018

TEMPERATURE (DEGREES F)
MAX…..60   NORMAL…..65
MIN…..52   NORMAL…..47
MEAN….56   NORMAL…..56

DEPARTURE FROM 30-YEAR NORMAL……………………0
TOTAL DEPARTURE FOR THE MONTH…………………..+4 [+1.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………9   DEPARTURE……….0
TOTAL HEATING UNITS FOR THE MONTH…………..21   DEPARTURE………-5
TOTAL HEATING UNITS FOR THE SEASON…………108   DEPARTURE……..-60
TOTAL HEATING UNITS LAST SEASON TO DATE…….119   DIFFERENCE…….-11

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……..+266
TOTAL COOLING UNITS LAST SEASON TO DATE…….707  DIFFERENCE…….+156

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..18 NNE AT 3:08  A.M.
AERO…………………….14 NNE AT 3:18  A.M.
ASOS…………………….16 NNE AT 3:07  A.M.
DAVIS……………………16 NE  AT 3:07  A.M. RMY 14
FASTEST MILE FOR YESTERDAY………………….11 NNE AT 3:12  A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….13 NNE AT 3:07  A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………12 NNE AT 3:00  A.M.
AVERAGE WIND SPEED AND DIRECTION……………4.9 N
ASOS……………………5.0
DAVIS…………………..5.2 NNE [32 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.01  DEPARTURE……-0.13
ASOS…………..0.01
TOTAL PRECIPITATION FOR THE MONTH……….1.32  DEPARTURE……+0.87
ASOS…………..1.34
TOTAL PRECIPITATION FOR THE YEAR……….48.40  DEPARTURE……+9.05
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 Low temp since midnight is 55F; 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 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