Sunday, October 15, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, OCTOBER 15, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

SOUTHERN WIND BRING WARM AND HUMID AIR

An overnight rainstorm left and additional 0.01 inches of
precipitation by 7:00 AM EST. The morning started with a
thick fog and precipitation that ended during the 7:00 AM EST
observation. Very light precipitation was observed again
around 12:00 PM EST leaving a trace by the 1:00 PM observation.

Winds coming from the south made for slightly above seasonable
and humid air today. Winds also increased today around 9:00 AM
EST after yesterdays calm winds. The day started with 100%
humidity and it dropped down to 82% by 1:00 PM EST. Visibility
was limited to 1/2 mile at 7:00 AM EST but increased to a surprising
60 miles at the 1:00 PM EST observation.

Today’s Observations:

7 A.M.
Weather: Fog
Temperature: 61F; Dew Point: 61F; Wind: S at 7 kts
Sea-level pressure: 30.08 ins. Hg, falling then steady
Visibility: 1/2 mile
6-hr Max temp: 60F
6-hr Min temp: 58F
24-hr precip: 0.05 ins.
BHO SA 1155 W3 X 1/2F 185/61/61/1907/008/ PCPN VRY LGT/
8//// 56010 MANUAL 70005 ASOS 70004 10060 20058

10 A.M.
Weather: Overcast stratus, few stratus fractus below summit
Temperature: 65F; Dew Point: 64F; Wind: SSW at 12G18 kts
Sea-level pressure: 30.02 ins. Hg, falling, then more quickly
Visibility: 20 miles distant fog in all directions
BHO SA 1455 E9 OVC 20 166/65/64/2012G18/002/ FEW STRA BLO SMT DSNT
FG ALQDS/ 8/6// 58019

1 P.M.
Weather: Scattered stratocumulus
Temperature: 69F; Dew Point: 63F; Wind: SSW at 12 kts
Sea-level pressure: 29.91 ins. Hg, falling, then more rapidly
Visibility: 60 miles
6-hr Max temp: 69F
6-hr Min temp: 60F
6-hr precip.: Trace
BHO SA 1755 E20 BKN 60 128/69/63/2012/991/ DSNT FG ALQDS/ 8/100 58038
MANUAL 600// 10069 20060

SUMMARY FOR SATURDAY, OCTOBER 14, 2017

TEMPERATURE (DEGREES F)
MAX…..66   NORMAL…..61
MIN…..54   NORMAL…..43
MEAN….60   NORMAL…..52

DEPARTURE FROM 30-YEAR NORMAL…………………….+8
TOTAL DEPARTURE FOR THE MONTH…………………..+108 [+7.5 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0   DEPARTURE………..0
TOTAL COOLING UNITS FOR THE MONTH…………..20   DEPARTURE………+16
TOTAL COOLING UNITS FOR THE SEASON…………727   DEPARTURE……..+126
TOTAL COOLING UNITS LAST SEASON TO DATE…….894   DEPARTURE……..-167

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………5   DEPARTURE……….-8
TOTAL HEATING UNITS FOR THE MONTH…………..57   DEPARTURE………-94
TOTAL HEATING UNITS FOR THE SEASON…………150   DEPARTURE……..-143
TOTAL HEATING UNITS LAST SEASON TO DATE…….198   DEPARTURE………-48

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….15  SSE AT  2:52 A.M.
AERO……………………13  SSE AT  2:52 A.M.
ASOS……………………14   SE AT  3:02 A.M.
DAVIS…………………..14  SSE AT  2:50 A.M.   RMY 13
FASTEST MILE FOR YESTERDAY…………………12  SSE AT  2:43 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………12  SSE AT  2:59 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..12  SSE AT  2:53 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..4.5  SSE
ASOS…………………..4.6
DAVIS………………….4.6  S  [186 DEG.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.05  DEPARTURE……-0.09
ASOS…………..0.04
TOTAL PRECIPITATION FOR THE MONTH……….0.50  DEPARTURE……-1.57
ASOS…………..0.50
TOTAL PRECIPITATION FOR THE YEAR……….42.36  DEPARTURE……+1.21
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

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  65/42/54/-3/0.00/697/99               18 WNW AERO 16 NW  RMY N/A
10/2  65/46/56/-1/0.00/687/98               21 NNW AERO 21 NNW RMY 21
10/3  67/50/59/+3/0.00/677/97               21 S   AERO 21 S   RMY N/A
10/4  75/50/63/+7/0.00/660/95               30 SSW AERO 30 SW  RMY 32
10/5  79/60/70/+14/0.00/…/..              28 SW  AERO 26 SW  RMY N/A
10/6  73/57/65/+10/T/…/..                 15 NW  AERO 14 NW  RMY 15
10/7  75/59/67/+12/T/…/..                 29 S   AERO 30 SSW RMY N/A
10/8  71/67/69/+15/0.23/…/..              33 S   AERO 36 SSW RMY 37
10/9  71/68/70/+16/0.22/…/..              43 S   AERO 41 S   RMY 45
10/10 76/61/69/+15/0.00/…/..              21 WNW AERO 20 WNW RMY 21
10/11 68/55/62/+9/0.00/…/..               29 ENE AERO 25 ENE RMY 29
10/12 58/48/50/0/T/…/..                   30 NE  AERO 28 ENE RMY 30
10/13 64/48/56/+3/0.00/…/..               20 E   AERO 16 E   RMY 17
10/14 66/54/60/+8/…/…/..                15 SSE AERO 13 SSE RMY 13

10/15 Low temp since midnight is 58F; normal low is now 43F

DAILY RECORDS FOR OCTOBER

10/8/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
BREAKS PREVIOUS RECORD OF 60F SET IN 1944

10/9/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 68F,
BREAKS PREVIOUS RECORD OF 61F SET IN 2011

10/9/17: MONTHLY RECORD HIGH MINIMUM TEMPERATURE OF 68F,
BREAKS PREVIOUS RECORD OF 67F SET ON OCTOBER 13, 1990
AND TIED ON OCTOBER 8, 2017

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

RECORDS FOR OCTOBER 15
HIGH 83F IN 1897
LOW 29F IN 1887,1937
PRECIP 4.58 INCHES IN 2005
SNOWFALL TRACE IN 1961,1972
PEAK GUST 69 MPH W IN 2003

RECORDS FOR OCTOBER 16
HIGH 86F IN 1897
LOW 28F IN 1886
PRECIP 2.82 INCHES IN 1974
SNOWFALL TRACE IN 2009
PEAK GUST 68e MPH SSE IN 1954 (HURRICANE HAZEL)

TODAY’S REPORT PREPARED BY: Kaitlin Geagan