Saturday, January 17, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, JANUARY 17, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

ARCTIC COLD AND SUNSHINE MAKE BRIEF RETURN TODAY WITH
DIMINISHING WINDS…

They sky has been nearly completely cloud free today with
only a few stratocumulus visible over the ocean to the
east and a few occasional mid-level clouds appearing to
the west this afternoon.  The low temperature of 5F this
morning was the coldest since January 8th, and the wind
chill early this morning was in the -5 to -10F range.
The strongest winds so far today occurred shortly after
midnight and have been diminishing to become light and
variable by early afternoon.  The visibility has been
excellent at 70-75 miles much of the day.

Today’s Observations:

7 A.M.
Weather: Clear, few stratocumulus along the horizon offshore
and distant NE-ESE
Temperature: 6F; Dew Point: -6F; Wind: NW at 8 kts
Sea-level pressure: 30.32 ins. Hg, rising steadily
Visibility: 70 miles, 80 miles SE-SW
6-hr max temp: 11F
6-hr min temp:  5F
24-hr precip.: Trace
24-hr snowfall: Trace
Snow Depth: Trace
BHO SA 1155 CLR 70 266/6/-6/3208/032/ FEW SC ALG HRZN OFFSHR
DSNT NE-ESE VSBY SE-SW 80/ 8/500 52033 10011 20005

10 A.M.
Weather: Clear, few stratocumulus along horizon offshore
and distant NE-ESE
Temperature: 11F; Dew Point: -5F; Wind: NW at 9 kts,
Sea-level pressure: 30.37 ins. Hg, rising slightly
Visibility: 75 miles
BHO SA 1455 CLR 75 283/11/-5/3209/037/ FEW SC ALG HRZN OFFSHR
DSNT NE-ESE/ 8/500 52017

1 P.M.
Weather: Clear, few stratocumulus distant ENE-ESE, few
altocumulus SW-NW
Temperature: 18F; Dew Point: -4F; Wind: NNW at 4 kts,
Wind: Light
Sea-level pressure: 30.32 ins. Hg, falling then more rapidly
Visibility: 75 miles
6-hr max temp: 19F
6-hr min temp:  6F
BHO SA 1755 CLR 75 266/18/-4/3404/032/ FEW SC DSNT ENE-ESE
FEW AC SW-NW WND LGT/ 8/503 58017 10019 20006

SUMMARY FOR FRIDAY, JANUARY 16, 2015

TEMPERATURE (DEGREES F)
MAX…..35   NORMAL…..33
MIN…..12   NORMAL…..17
MEAN….24   NORMAL…..25

DEPARTURE FROM 30-YEAR NORMAL……………………..-1
TOTAL DEPARTURE FOR THE MONTH…………………….-43 [-2.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..41  DEPARTURE………..+1
TOTAL HEATING UNITS FOR THE MONTH………….672  DEPARTURE……….+45
TOTAL HEATING UNITS FOR THE SEASON………..2732  DEPARTURE………-200
TOTAL HEATING UNITS LAST SEASON TO DATE……2873  DIFFERENCE……..-141

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………46 W   AT  4:08 P.M.
ASOS…………………..53 WNW AT  4:08 P.M.
DAVIS………………….48 WNW AT  4:07 P.M. RMY 50
FASTEST MILE FOR YESTERDAY………………..39 W   AT  4:11 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..37 W   AT  4:09 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….34 W   AT  4:09 P.M.
AVERAGE WIND SPEED AND DIRECTION…………17.2 WSW
ASOS…………………16.3
DAVIS………………..14.9 W [272 degrees] * last of several occurrences….

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…Trace  DEPARTURE…..-0.14
ASOS………….Trace
TOTAL PRECIPITATION FOR THE MONTH……….1.58  DEPARTURE…..-0.70
ASOS…………..1.60
TOTAL PRECIPITATION FOR THE YEAR………..1.58  DEPARTURE…..-0.70
ASOS…………..1.60

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……..Trace  DEPARTURE……-0.5
TOTAL SNOWFALL FOR THE MONTH…………….4.9  DEPARTURE……-4.1
TOTAL SNOWFALL FOR THE SEASON…………..15.9  DEPARTURE……-9.1

PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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

1/1  31/18/25/-2/0.00/0.0/544/99              29 SSW RMY 30
1/2  37/26/32/+5/0.00/0.0/314/57              35 WSW RMY 38
1/3  34/21/28/+2/0.67/2.5/017/03              25 SE  RMY 26
1/4  51/33/42/+16/0.48/0.0/000/00             30 SSW RMY N/A
1/5  46/13/30/+4/0.00/0.0/542/98              48 W   RMY 54
1/6  15/10/13/-13/0.02/0.4/000/00             29 W   RMY N/A
1/7  22/01/12/-14/0.01/0.3/394/71             43 WNW RMY 47
1/8  16/-5/6/-20/0.00/0.0/539/97              39 WNW RMY N/A
1/9  27/16/22/-4/0.08/0.9/…/..              35 WSW RMY 38
1/10 22/11/17/-8/0.00/0.0/541/97              26 WNW RMY 27
1/11 31/9/20/-5/45/0.00/0.0/123/22            26 SSW RMY N/A
1/12 36/31/34/+9/0.23/T/000/00                29 NNW RMY N/A
1/13 33/11/22/-3/0.00/0.0/524/93              30 NNW RMY 29
1/14 22/11/17/-8/T/T/000/00                   18 NNW RMY 16
1/15 27/20/24/-1/0.09/0.8/000/00              20 WSW RMY 22
1/16 35/12/24/-1/T/T/…/..                   46 WSW RMY 50

1/17 morning low temp: 5F since midnight; normal low is now 17F

DAILY RECORDS FOR JANUARY 2015
None so far.

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

RECORDS FOR JANUARY 17
HIGH 55F IN 1973,1995
LOW -8F IN 1907,1982
PRECIP 1.43 INS. IN 1956
SNOWFALL 13.4 INS. IN 1956
PEAK GUST 62 MPH S IN 1994

RECORDS FOR JANUARY 18
HIGH 62F IN 1973,1990
LOW -10F IN 1982
PRECIP 1.68 INS. IN 1915
SNOWFALL 13.0 INS. IN 1948
PEAK GUST 85 MPH SSE IN 2006

TODAY’S REPORT PREPARED BY: Mike Iacono / Rob Millette