Friday, October 19, 2018

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, OCTOBER 19, 2018
ALL TIMES ARE IN EASTERN STANDARD TIME

FAIR WEATHER TODAY FOLLOWING FREEZING OVERNIGHT
TEMPERATURES….

Temperatures decreased to 31F this morning, at 4 A.M.
Skies remained mostly clear today, with some high
cirrus clouds at 1 P.M. Dry air in the region allowed
a visibility of 70 miles throughout the day. Pressure fell
by over 5 millibars since the 7 A.M. observation. Winds have
increased after noontime, with frequent gusts over
20 mph from the SW. The high temperature so far today
is 58F, which is a degree below the daily normal of 59F.
The low since midnight is 31, 11 degrees below the
normal minimum of 42F.

The freezing temperature this morning was one day earlier
than the long-term average date of the first freeze at the
Observatory of October 20th.

Today’s Observations:

7 A.M.
Weather: Few distant altostratus in all directions
Temperature: 35F; Dew Point: 25F; Wind: SW at 10G16 kts
Sea-level pressure: 30.24 ins. Hg, falling then rising
Visibility: 70 miles
6-hr Max temp: 35F
6-hr Min temp: 31F
24-hr Precip: 0.00 ins.
BHO SA 1155 CLR 70 242/35/25/2210G16/024/ FEW DSNT AS ALQDS/
8/020 55002 10035 20031

10 A.M.
Weather: Few distant cirrostratus in all directions
Temperature: 48F; Dew Point: 30F; Wind: SW at 12G18 kts
Sea-level pressure: 30.19 ins. Hg, falling rapidly
Visibility: 70 miles
3-hr Precip: 0.00 ins.
BHO SA 1455 CLR 70 223/48/30/2312G18/019/ FEW DSNT CS ALQDS/
8/005 58019

1 P.M.
Weather: Scattered Cirrus
Temperature: 57F; Dew Point: 33F; Wind: SW at 17G22 kts
Sea-level pressure: 30.09 ins. Hg, falling rapidly
Visibility: 70 miles
6-hr Max temp: 58F
6-hr Min temp: 35F
6-hr Precip: 0.00 ins.
BHO SA 1755 250 SCT 70 188/57/33/2417G22/009/ 8/002 58035
10058 20035

SUMMARY FOR THURSDAY, OCTOBER 18, 2018

TEMPERATURE (DEGREES F)
MAX…..45   NORMAL…..60
MIN…..33   NORMAL…..42
MEAN….39   NORMAL…..51

DEPARTURE FROM 30-YEAR NORMAL………………….-12
TOTAL DEPARTURE FOR THE MONTH…………………..36 [+1.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..26   DEPARTURE………+1
TOTAL HEATING UNITS FOR THE MONTH………….173   DEPARTURE……..-33
TOTAL HEATING UNITS FOR THE SEASON…………260   DEPARTURE……..-88
TOTAL HEATING UNITS LAST SEASON TO DATE…….188   DIFFERENCE…….+72

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY……………0  DEPARTURE………..0
TOTAL COOLING UNITS FOR THE MONTH…………..11  DEPARTURE……….+6
TOTAL COOLING UNITS FOR THE SEASON…………874  DEPARTURE……..+272
TOTAL COOLING UNITS LAST SEASON TO DATE…….727  DIFFERENCE…….+147

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………..32 WNW AT 11:36 A.M.
AERO…………………….35 WNW AT  9:00 A.M.
ASOS…………………….35 NW  AT 11:39 A.M.
DAVIS……………………37 WNW AT  1:06 A.M. RMY 36
FASTEST MILE FOR YESTERDAY………………….25 WNW AT  9:28 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………….23 NW  AT  9:28 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE………………25 WNW AT  3:17 A.M.
AVERAGE WIND SPEED AND DIRECTION……………15.5 WNW
ASOS……………………14.3
DAVIS…………………..15.7 WNW [296 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00  DEPARTURE……-0.16
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….2.76  DEPARTURE……+0.08
ASOS…………..2.76
TOTAL PRECIPITATION FOR THE YEAR……….49.96  DEPARTURE……+8.38
ASOS………….51.68

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

10/01 65/53/59/+2/…./042/06         21 ENE AERO 18 SSW RMY N/A
10/02 64/53/59/+2/…./000/00         33 S   AERO 32 S   RMY 35 TSTM
10/03 60/52/56/0/…./000/00          18 NNE AERO 14 NNE RMY 14
10/04 69/57/63/+7/…./209/30         29 SSW AERO 29 SSW RMY 32
10/05 64/47/56/0/…./638/92          25 NE  AERO 21 NE  RMY 24
10/06 64/45/55/0/0.00/276/40          23 SSW AERO 23 SSW RMY 25
10/07 75/56/66/+11/…./076/11        28 NE  AERO 24 ENE RMY 27
10/08 56/53/55/+1/…./000/00         22 ENE AERO 20 ENE RMY N/A
10/09 75/56/66/+12/…./211/31        26 WSW AERO 28 SW  RMY 29
10/10 82/65/74/+20/…./496/73        24 WSW AERO 23 WSW RMY 25
10/11 70/56/63/+10/…./…/..        48 NNE AERO 47 NNE RMY 50
10/12 59/44/52/-1/…./…/..         32 NW  AERO 32 NW  RMY 33
10/13 49/40/45/-8/…./…/..         21 WNW AERO 20 WNW RMY 20
10/14 55/37/46/-6/…./…/..         21 W   AERO 18 W   RMY 21
10/15 66/44/55/+3/…./…/..         46 W   AERO 46 W   RMY N/A
10/16 56/41/49/-2/…./…/..         48 W   AERO 48 W   RMY N/A
10/17 60/39/50/-1/…./…/..         48 W   AERO 50 W   RMY 53
10/18 45/33/39/-12/…./…/..        32 WNW AERO 35 WNW RMY 36

10/19 Low temp since midnight is 31F; normal low is 42F

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

RECORDS FOR OCTOBER 19
HIGH 81F IN 1945
LOW 21F IN 1922
PRECIP 3.64 INCHES IN 1932
SNOWFALL 1.0 INCHES IN 1972
PEAK GUST 66 MPH SSW IN 1967

RECORDS FOR OCTOBER 20
HIGH 78F IN 1965,1984
LOW 24F IN 1972
PRECIP 7.10 INCHES IN 1996 (RECORD FOR MONTH)
SNOWFALL TRACE IN 1934,1943
PEAK GUST 63 MPH W IN 1966

TODAY’S REPORT PREPARED BY: Benjamin Turner