Thursday, September 15, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, SEPTEMBER 15, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

MOSTLY CLOUDY SKIES CLEAR AS HIGH PRESSURE MOVES EAST

This morning started out cool and cloudy with broken stratocumulus
during the 7:00AM EST observation.  The temperature measured just 57F,
only 5F above the overnight low of 52F.  Skies gradually cleared as
high pressure over the Great Lakes continued moving east leaving us
with scattered cumulus at the 1:00PM observation.

Yesterday’s max. temp. of 87F was 15F above normal and occurred before
the passage of a cold front.  The front left the observatory with just
a trace of precipitation.  Temperatures have been much cooler today with
the max. temp. at 1:00PM measuring 67F.

7 A.M.
Weather: Broken stratocumulus
Temperature: 57F; Dew Point: 48F; Wind: N at 7 kts
Sea-level pressure: 30.26 ins. Hg, rising, then more quickly
Visibility: 70 miles
6-hr Max temp: 57F
6-hr Min temp: 52F
24-hr precip: Trace
BHO SA 1155 E42 BKN 70 246/57/48/3607/026/ 8/500 51019 10057 20052

10 A.M.
Weather: Scattered cumulus, broken stratocumulus
Temperature: 61F; Dew Point: 49F; Wind: NE at 9G17 kts
Sea-level pressure: 30.30 ins. Hg, rising, then less quickly
Visibility: 70 miles
BHO SA 1455 22 SCT E42 BKN 70 260/61/49/0409G17/030/ 8/500 51014

1 P.M.
Weather: Scattered cumulus
Temperature: 66F; Dew Point: 49F; Wind: NE at 7 kts
Sea-level pressure: 30.27 ins. Hg, falling, then more quickly
Visibility: 70 miles
6-hr Max. temp: 67F
6-hr Min. temp: 56F
BHO SA 1755 42 SCT 70 251/66/49/0507/027/ 8/100 58009 10067 20056

SUMMARY FOR WEDNESDAY, SEPTEMBER 14, 2016

TEMPERATURE (DEGREES F)
MAX…..87   NORMAL…..72
MIN…..58   NORMAL…..55
MEAN….73   NORMAL…..64

DEPARTURE FROM 30-YEAR NORMAL……………………+9
TOTAL DEPARTURE FOR THE MONTH…………………..+47 [+3.2 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………8   DEPARTURE……….+6
TOTAL COOLING UNITS FOR THE MONTH…………..63   DEPARTURE………+22
TOTAL COOLING UNITS FOR THE SEASON…………855   DEPARTURE……..+277
TOTAL COOLING UNITS LAST SEASON TO DATE…….758   DIFFERENCE……..+97

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………0   DEPARTURE……….-3
TOTAL HEATING UNITS FOR THE MONTH……………0   DEPARTURE………-28
TOTAL HEATING UNITS FOR THE SEASON………….10   DEPARTURE………-43
TOTAL HEATING UNITS LAST SEASON TO DATE………6   DIFFERENCE………+4

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….35 NNW AT 8:12 P.M.
ASOS……………………34 NW  AT 8:13 P.M.
DAVIS…………………..32 W   AT 3:05 P.M. RMY 35
FASTEST MILE FOR YESTERDAY…………………25 W   AT 3:06 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………24 W   AT 3:09 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..24 W   AT 3:09 P.M.
AVERAGE WIND SPEED AND DIRECTION………….13.8 NNW
ASOS………………….13.5
DAVIS…………………12.1 WSW [250 Deg.] * Last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…TRACE  DEPARTURE……-0.14
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….1.31  DEPARTURE……-0.44
ASOS…………..1.30
TOTAL PRECIPITATION FOR THE YEAR……….26.28  DEPARTURE…..-10.49
ASOS………….26.57

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  72/64/68/0/0.09/000/00                  21 NNW AERO 16 NNW RMY 20
9/2  76/58/67/-1/0.00/738/94                 23 ENE AERO 17 NE  RMY 23
9/3  71/56/64/-3/0.00/368/47                 16 E   AERO 12 E   RMY N/A
9/4  71/58/65/-2/0.00/740/95                 28 NE  AERO 21 NE  RMY 27
9/5  73/57/65/-2/0.52/241/31                 42 NNE AER0 33 NNE RMY 43
9/6  70/61/66/-1/0.54/046/06                 32 N   AERO 23 NNE RMY N/A
9/7  78/66/72/+6/0.05/339/44                 21 NE* AERO 15 NE* RMY 21
9/8  79/65/72/+6/T/276/36                    22 S   AERO 15 S   RMY 23
9/9  90/69/80/+14/T/421/55                   23 W   AERO 24 W   RMY 25
9/10 82/71/77/+12/T/…/..                   25 S   AERO 18 S   RMY 32
9/11 79/59/69/+4/0.10/…/..                 39 WNW AERO 30 WNW RMY 43
9/12 76/53/65/0/0.00/…/..                  18 SW* AERO 13 WNW RMY 19
9/13 81/57/69/0.00/…/..                    25 SSW AERO  M     RMY 26
9/14 87/58/73/T/…/..                       35 NNW AERO  M     RMY 35

9/15 Low temp since midnight is 52F; normal low is now 55F

DAILY RECORDS FOR SEPTEMBER 2016

9/10/16: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F,
BREAKS PREVIOUS RECORD OF 69F SET IN 1915, 1931, AND 1989

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

RECORDS FOR SEPTEMBER 15
HIGH 89F IN 1931
LOW 35F IN 1913
PRECIP 3.93 INCHES IN 1904 (Extra-tropical storm making landfall in
New England on 9/15/1904 passing east of BHO and bringing a storm
total of 4.11 inches 9/14-15/1904)
PEAK GUST 65e MPH NW, WSW IN 1944 (In the wake of Great Atlantic Hurricane)

RECORDS FOR SEPTEMBER 16
HIGH 91F IN 1939,1941
LOW 39F IN 1984
PRECIP 5.12 INCHES IN 1933 (Hurricane)
PEAK GUST 59 MPH SSE IN 1999

TODAY’S REPORT PREPARED BY: Cecilia Borries-Strigle