Wednesday, September 20, 2017
BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, SEPTEMBER 20, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME
INCREASING WINDS AS TROPICAL STORM JOSE TURNS NORTHEAST
Blue Hill Observatory was surrounded by thick fog today
with visibility increasing to just 1 mile in the after-
noon. The fog has helped to keep temperatures steady,
and there has been just a 4F variation between yesterday’s
minimum temperature of 61F and today’s maximum temperature
of 65F. A mixture of rain and drizzle over night made the
24-hour total 0.47 inches at 7:00AM EST today. An additional
0.10 inches has fallen since then. Winds have been increasing
through the morning and into the early afternoon. The peak
gust so far today is 37 MPH out of the north-northeast at 12:29PM.
Today’s Observations:
7 A.M.
Weather: Light drizzle, sky obscurement due to fog
Temperature: 64F; Dew Point: 64F; Wind: NNE at 15G26 kts,
Peak wind: 27 kts (31 MPH) NNE at 6:13AM EST
Sea-level pressure: 30.12 ins. Hg, falling then rising
Visibility: 1/8 mile
6-hr Max temp: 64F
6-hr Min temp: 62F
24-hr Precip: 0.47 in.
BHO SA 1155 W2 X 1/8L-F 121/64/64/0215G26/989/ PK WND 0227/13/
8//// 50002 MANUAL 70047 ASOS 70049 10064 20062
10 A.M.
Weather: Sky obscurement due to fog
Temperature: 65F; Dew Point: 65F; Wind: NNE at 17G30 kts,
Peak wind: 30 kts (35 MPH) NNE at 9:52AM EST
Sea-level pressure: 29.88 ins. Hg, rising then falling
Visibility: 1/8 mile
3-hr Precip: 0.05 in.
BHO SA 1455 W3 X 1/8F 119/65/65/0217G30/988/ PK WND 0330/52/
8//// 580012 MANUAL 6005/ ASOS 60005
1 P.M.
Weather: Light rain, sky obscurement due to fog
Temperature: 65F; Dew Point: 65F; Wind: NNE at 19G28 kts,
Peak wind: 32 kts (37 MPH) NNE at 12:29PM EST
Sea-level pressure: 29.85 ins. Hg, falling, then more quickly
Visibility: 1 mile
6-hr Max temp: 65F
6-hr Min temp: 64F
6-hr Precip: 0.10 in.
BHO SA 1755 W3 X 1R-F 110/65/65/0219G28/985/ PK WND 0232/29/
8//// 58009 MANUAL 6010/ ASOS 60011 10065 20064
SUMMARY FOR TUESDAY, SEPTEMBER 19, 2017
TEMPERATURE (DEGREES F)
MAX…..63 NORMAL…..71
MIN…..61 NORMAL…..54
MEAN….62 NORMAL…..62
DEPARTURE FROM 30-YEAR NORMAL……………………..0
TOTAL DEPARTURE FOR THE MONTH……………………+20 [+0.9 DEGREES/DAY]
COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0 DEPARTURE……….-1
TOTAL COOLING UNITS FOR THE MONTH…………..58 DEPARTURE……….+9
TOTAL COOLING UNITS FOR THE SEASON…………665 DEPARTURE………+79
TOTAL COOLING UNITS LAST SEASON TO DATE…….867 DEPARTURE……..-202
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………3 DEPARTURE……….-1
TOTAL HEATING UNITS FOR THE MONTH…………..34 DEPARTURE………-13
TOTAL HEATING UNITS FOR THE SEASON………….60 DEPARTURE………-12
TOTAL HEATING UNITS LAST SEASON TO DATE……..17 DEPARTURE………+43
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….28 NE AT 12:52 P.M.*
AERO……………………25 NNE AT 11:14 P.M.
ASOS……………………30 NE AT 1:02 P.M.
DAVIS…………………..26 NE AT 12:51 P.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………21 NNE AT 1:04 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………22 NE AT 10:05 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..20 NNE AT 1:03 P.M.
AVERAGE WIND SPEED AND DIRECTION………….13.7 NNE
ASOS………………….14.4
DAVIS…………………12.0 NNE [029 DEG.]
*last of multiple occurrences
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.47 DEPARTURE……+0.33
ASOS…………..0.49
TOTAL PRECIPITATION FOR THE MONTH……….2.08 DEPARTURE……-0.36
ASOS…………..2.11
TOTAL PRECIPITATION FOR THE YEAR……….38.44 DEPARTURE……+0.98
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings
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
9/1 68/47/58/-10/0.00/749/95 26 WNW AERO 28 WNW RMY 31
9/2 72/46/59/-9/0.00/542/69 18 NNW AERO 18 NNW RMY 21
9/3 63/52/58/-9/0.24/000/00 33 W AERO 33 W RMY 37
9/4 79/55/67/0/0.00/702/90 29 SSW AERO 28 SSW RMY N/A
9/5 84/62/73/+6/0.00/583/75 36 S AERO 32 S RMY 38
9/6 76/59/68/+1/0.49/070/09 28 S AERO 28 S RMY 30 TSTM
9/7 74/58/66/0/0.79/417/54 24*WSW AERO 23 WSW RMY 24
9/8 74/53/64/-2/0.00/577/75 21 WSW AERO 18 WSW RMY 22
9/9 68/51/60/-5/T/620/81 18 ENE AERO 16 ENE RMY 18
9/10 71/51/61/-4/0.00/694/91 18 NW AERO 16 NW RMY N/A
9/11 78/50/64/-1/0.00/692/91 20 NNW AERO 17 NNW RMY 20
9/12 84/58/71/+6/0.00/690/91 22 WSW AERO 18 WSW RMY 23
9/13 84/59/72/+8/T/680/90 18 WSW AERO 15 WSW RMY 20 TSTM
9/14 82/66/74/+10/0.00/233/31 23 SW AERO 23 WSW RMY 25 TSTM
9/15 83/66/75/+11/0.05/300/40 18 WNW AERO 15 WNW RMY 18
9/16 78/65/72/+9/T/…/.. 14 E AERO 9 E RMY 12
9/17 79/61/70/+7/T/…/.. 15 SSE AERO 14 SSE RMY 15
9/18 67/62/65/+3/…./…/.. 21 NE AERO 18 NE RMY N/A
9/19 63/61/62/0/…./…/.. 28 NE* AERO 25 NNE RMY N/A
9/20 Low temp since midnight is 62F; normal low is now 53F
DAILY RECORDS FOR SEPTEMBER
9/1/17: DAILY RECORD LOW MINIMUM TEMPERATURE OF 47F,
TIES PREVIOUS RECORD SET IN 1975
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
RECORDS FOR SEPTEMBER 20
HIGH 90 IN 1983
LOW 34 IN 1979
PRECIP 4.57 INS IN 1899
PEAK GUST 44 MPH NE IN 1972
RECORDS FOR SEPTEMBER 21
HIGH 91 IN 1895
LOW 35 IN 1929, 1956, 1962
PRECIP 5.58 INS IN 1961 (HURRICANE ESTHER; RETURNED AS TS SEPT 25-26TH)
PEAK GUST 186 MPH S IN 1938 (GREAT NEW ENGLAND HURRICANE;
CALCULATED GUST, STATION RECORD)
TODAY’S REPORT PREPARED BY: Cecilia Borries-Strigle
