Saturday, December 7, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, DECEMBER 7, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT RAIN OVERNIGHT TURNS TO SLEET AND SNOW EARLY THIS MORNING…
ONLY A TRACE OF FROZEN PRECIPITATION MEASURED ON THE SUMMIT…
PARTIAL SUNSHINE RETURNS TODAY…

Steady light rain began Friday evening near 6 pm EST and this continued
until shortly after 1 AM EST this morning. The precipitation continued
briefly in the form of freezing rain and ended well before sunrise as
a period of mixed ice pellets and snow.  A trace of snow and sleet
remained on the snow boards and in patches on the ground as of 7 AM EST
today. Dense fog early this morning lifted by mid-morning, and a few
additional light snow showers were observed between 7:50 and 9:20 AM EST,
which amounted to a trace. The sun came out for a few hours at mid-day,
though low clouds began to return as of mid-afternoon.

Today’s Observations:

7 A.M.
Weather: Sky obscured by dense fog, light glaze on all metal and wood
surfaces
Temperature: 32F; Dew Point: 31F; Wind: NW at 5 kts.
Sea-level pressure: 30.18 ins. Hg, rising
Visibility: 1/16 mile, dense fog
24-hr precip: 0.50 inch
24-hr snowfall: Trace
6-hr min temp: 31F
BHO SA 1155 W2 X 1/16F 219/32/31/3106/018/ LT GLZ METAL/WOOD SFCS WND LGT/
8//// 53018 60/// 70050 10032 20031

10 A.M.
Weather: Scattered cumulus, scattered altocumulus, thin scattered
cirrus, few lower cumulus all quadrants, few cumulus fractus vicinity
station, snow shower ended 9:20 EST, light haze
Temperature: 34F; Dew Point: 32F; Wind: WNW at 7 kts.
Sea-level pressure: 30.23 ins. Hg, rising
Visibility: 35 miles
3-hr precip: Trace
BHO SA 1455 40 SCT 85 SCT 250 –SCT 35 238/34/32/3007/023/ FEW LWR CU ALQDS
FEW CUFRA VCNTY STN SW-E20 LGT HZ/ 8/171 53019 6000/

1 P.M.
Weather: Scattered stratocumulus, scattered altocumulus
Temperature: 38F; Dew Point: 28F; Wind: WNW at 13 kts.
Sea-level pressure: 30.22 ins. Hg, falling
Visibility: 65 miles
6-hr. max temp. 39F
6-hr precip: Trace
6-hr snowfall: Trace
BHO SA 1755 30 SCT 85 SCT 65 234/38/28/3013/022/ 8/570 56004 6000/
10039 20032

WEATHER SUMMARY FOR FRIDAY, DECEMBER 6, 2013

TEMPERATURE (DEGREES F)
MAX…..55    NORMAL…..42
MIN…..33    NORMAL…..27
MEAN….44    NORMAL…..35

DEPARTURE FROM 30-YEAR NORMAL………………….+9
TOTAL DEPARTURE FOR THE MONTH…………………+25 [+4.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..21  DEPARTURE………-9
TOTAL HEATING UNITS FOR THE MONTH………….151  DEPARTURE……..-26
TOTAL HEATING UNITS FOR THE SEASON………..1375  DEPARTURE……..-63
TOTAL HEATING UNITS LAST SEASON TO DATE……1294  DIFFERENCE…….+81

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………25 SSW AT  1:15 A.M. *
AERO…………………..28 SSW AT  1:01 A.M.
ASOS…………………..29 SSW AT  1:15 A.M.
DAVIS………………….28 SSW AT  1:15 A.M. RMY 21
FASTEST MILE FOR YESTERDAY………………..22 SSW AT  1:04 A.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE……………..23 SSW AT  1:02 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….22 SSW AT  1:02 A.M.
AVERAGE WIND SPEED AND DIRECTION…………12.1 NW
ASOS…………………11.5
DAVIS………………..10.4 W  [273 degrees] * last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.50  DEPARTURE………….+0.34
ASOS…………..0.47
TOTAL PRECIPITATION FOR THE MONTH……….0.80  DEPARTURE………….-0.18
ASOS…………..0.76
TOTAL PRECIPITATION FOR THE YEAR……….47.40  DEPARTURE………….-2.11
ASOS…………..N/A**
** ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M…..Trace     DEPARTURE………….-0.3
TOTAL SNOWFALL FOR THE MONTH………..Trace     DEPARTURE………….-1.7
TOTAL SNOWFALL FOR THE SEASON…………0.2     DEPARTURE………….-4.1

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized

12/1  45/30/38/+1/0.28/T/000/00           22 SSE AERO 23 MPH SSE RMY 23
12/2  38/34/36/0/T/0.0/000/00             15 NW  AERO 15 MPH NW  RMY N/A
12/3  45/32/39/+3/0.00/0.0/…/..         18 NNW AERO 18 MPH NNW RMY 20
12/4  43/29/36/+1/0.00/0.0/…/..         21 WNW AERO 21 MPH WNW RMY 21
12/5  53/38/46/+11/…./0.0/000/00        36 S   AERO 40 MPH S   RMY 39
12/6  55/33/44/+9/…./../000/00          25 SSW AERO 28 MPH SSW RMY N/A

12/7  morning low temp since midnight: 31F; the normal low is now 27F

DAILY RECORDS FOR DECEMBER 2013
None so far.

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

RECORDS FOR DECEMBER 7
HIGH 74 IN 1998
LOW 6 IN 1906
PRECIP 1.67 INS. IN 1953
SNOWFALL 6.3 INS. IN 2003
PEAK GUST 76e SE IN 1976

RECORDS FOR DECEMBER 8
HIGH 62 IN 1966
LOW -4 IN 1906
PRECIP 1.54 INS. IN 1969
SNOWFALL 2.5 INS. IN 2001
PEAK GUST 78e W IN 1979

TODAY’S REPORT PREPARED BY: Mike Iacono