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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, DECEMBER 22, 2012
ALL TIMES ARE IN EASTERN STANDARD TIME

PARTLY SUNNY, COLDER AND VERY WINDY AGAIN TODAY...
SNOW SHOWER BRINGS ONLY A TRACE OF SNOW...

The storm total precipitation on Friday was 0.90 inch, which fell
entirely as rain through early afternoon.  The peak gust yesterday
was 58 mph from the E at 10:53 AM, and this was the highest gust
for the month so far.  Although the sun has returned today, winds
have remained very gusty from the west reaching a peak gust of 
47 mph out of the W at 10:32 AM.  A very strong area of low
pressure in southern Canada is departing to the northeast, though
it is continue to cause snow showers across New England and
Lake Effect snow in New York state. A snow shower on the summit
began at 9:10 AM and continued through 9:45 AM.  Although the
visibility briefly dropped to only a few miles during the snow
only a trace of precipitation and a trace of snow was recorded.
There was no accumulation with the temperature in the middle 30s
at the time.  The visibility quickly climbed behind the snow
shower as much drier air began to move in.  The dew point has
dropped from the upper 20s early today to the upper teens by
early afternoon. 


Today's observations:
 
7 A.M.
Weather: Scattered stratocumulus, overcast altocumulus, few lower 
stratocumulus distant W-NW, thin spots in overcast all quadrants, 
breaks in overcast distant N and E, hazy
Temperature: 34F; Dew Point: 29F; Wind: SW at 10kts,
Sea-level pressure: 29.30 ins. Hg, rising then rising more rapidly 
Visibility: 35 miles, hazy
24-hour precip: 0.84 inch
6-hour min. temp: 33F
BHO SA 1155 55 SCT E70 OVC 35 923/34/29/2210/930/ FEW LWR SC DSNT W-NW 
THN SPTS IOVC ALQDS BINOVC DSNT N AND E HAZY/ 8/57/ 53017 70084 10035 
20033 

10 A.M. 
Weather: Scattered stratocumulus, broken altocumulus, overcast cirrus,
few lower stratocumulus, few stratocumulus castellanus NE, breaks in 
overcast S-SW and overhead-N, snow shower N-SSE moving E, show shower
began 9:10 AM ending 9:45 AM
Temperature: 35F; Dew Point: 27F; Wind: W at 17G24 kts,
Wind: Peak gust 34 kts W at 9:35 AM
Wind: Direction variable SW-WNW
Sea-level pressure: 29.36 ins. Hg, rising then rising more slowly
Visibility: 35 miles, 20 N-NE, 25 E-SE, 70 SW-NW
3-hour precip: Trace
3-hour snowfall: Trace
BHO SA 1455 45 SCT 65 SCT E120 BKN 200 OVC 35 942/35/27/2617G24/936/ FEW 
LWR SC FEW SCCAS NE BINOVC S-SW AND OVHD-N VSBY N-NE 20 E-SE 25 SW-NW 70 
SW N-SSE MVNG E SWB10E45 PK WND 2734/35 WND 23V29/ 8/571 51019 6000/ 

1 P.M.
Weather: Broken stratocumulus, broken altocumulus, broken cirrus,
few cumulus fractus overhead, few lower stratocumulus all quadrants,
virga distant SSW-N
Temperature: 35F; Dew Point: 17F; Wind: W at 19G32 kts,
Wind: Peak gust 35 kts W at 12:03 PM
Wind: Direction variable WSW-WNW 
Sea-level pressure: 29.37 ins Hg, steady then rising
Visibility: 70 miles, 55 SE-S, 75 miles WNW-NW  
6-hour precip: Trace
6-hour snowfall: Trace
6-hour max. temp: 37F 
BHO SA 1755 E45 BKN 120 BKN 200 BKN 70 945/35/17/2719G32/937/ FEW CUFRA 
OVHD FEW LWR SC ALQDS VIRGA DSNT SSW-N VSBY SE-S 55 WNW-NW 75 PK WND 
2735/03 WND 24V30/ 8/531 53003 6000/ 10037 20032


WEATHER SUMMARY FOR FRIDAY, DECEMBER 21

TEMPERATURE (DEGREES F)
MAX.....53      NORMAL.....37
MIN.....35      NORMAL.....22
MEAN....44      NORMAL.....30
 
DEPARTURE FROM 30-YEAR NORMAL.....................+14
TOTAL DEPARTURE FOR THE MONTH....................+145 [+6.7 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............21    DEPARTURE........-14
TOTAL HEATING UNITS FOR THE MONTH...........526    DEPARTURE.......-148 
TOTAL HEATING UNITS FOR THE SEASON.........1676    DEPARTURE.......-259
TOTAL HEATING UNITS LAST SEASON TO DATE....1454    DIFFERENCE......+222

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...............58 E   AT  10:53 A.M.
                   AERO....................53 E   AT  10:53 A.M.
                   ASOS....................59 ESE AT  10:54 A.M.
                   DAVIS...................56 E   AT  10:54 A.M.  RMY: 57  
THE FASTEST MILE FOR YESTERDAY.............40 SE  AT  1:40  P.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE..............38 SE  AT  1:28  P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.............37 SE  AT  1:22  P.M.
AVERAGE WIND SPEED AND DIRECTION.........22.6 ESE
                   ASOS..................22.3
                   DAVIS.................20.2 SSE [147 deg.]
* last of several occurrences
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.84   DEPARTURE..........+0.69
                         ASOS..............0.82
TOTAL PRECIPITATION FOR THE MONTH..........3.52   DEPARTURE..........+0.13
                         ASOS..............3.54
TOTAL PRECIPITATION FOR THE YEAR..........38.40   DEPARTURE.........-13.52
                         ASOS.............38.43

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0    DEPARTURE..........-0.4
TOTAL SNOWFALL FOR THE MONTH...............0.9    DEPARTURE..........-7.3
TOTAL SNOWFALL FOR THE SEASON..............6.9    DEPARTURE..........-3.9	

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2012 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/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  34/25/30/-7/0.08/0.8/000/00     16 E   AERO 14 MPH E   RMY 16
12/2  52/32/42/+6/0.00/0.0/006/01     32 SSW AERO 32 MPH SSW RMY 34
12/3  57/43/50/+14/0.00/0.0/523/94    31 NW  AERO 30 MPH NW  RMY 32
12/4  56/40/48/+13/0.03/0.0/000/00    37 S   AERO 39 MPH S   RMY 38 
12/5  56/31/44/+9/0.03/0.0/310/56     38 WNW AERO 37 MPH WNW RMY 40
12/6  38/25/32/-3/0.00/0.0/519/94     31 NW  AERO 30 MPH NW  RMY N/A
12/7  42/30/36/+2/0.02/0.0/000/00     18 SSW AERO 16 MPH SSW RMY 18        
12/8  45/41/43/+9/0.35/0.0/000/00     21 ENE AERO 18 MPH ENE RMY N/A
12/9  45/38/42/+8/0.10/0.0/181/33     24 NNW AERO 24 MPH NNW RMY 25
12/10 59/39/49/+16/0.51/0.0/000/00    32 SSW AERO 33 MPH SSW RMY 35
12/11 54/30/42/+9/0.01/0.0/351/64     25 W   AERO 25 MPH W   RMY 23
12/12 38/26/32/-1/0.00/0.0/.../..     20 NW  AERO 18 MPH NW  RMY N/A
12/13 42/29/36/+4/0.00/0.0/.../..     18 NW  AERO 15 MPH NW  RMY N/A
12/14 47/29/38/+6/0.00/0.0/.../..     28 W   AERO 25 MPH W   RMY 27
12/15 40/31/36/+4/0.00/0.0/.../..     24 NNW AERO 22 MPH NNW RMY 21
12/16 36/31/34/+3/0.25/0.1/.../..     25 E   AERO 22 MPH E   RMY N/A
12/17 44/36/40/+9/0.65/0.0/000/00     31 ENE AERO 29 MPH ENE RMY 30
12/18 50/40/45/+14/0.61/0.0/000/00    28 E   AERO 24 MPH E   RMY N/A
12/19 44/35/40/+10/T/0.0/.../..       42 WNW AERO 40 MPN WNW RMY 43
12/20 42/30/36/+6/T/0.0/.../..        25 NNW AERO 23 MPH NNW RMY N/A
12/21 53/35/44/+14//0.0/.../..        58 E   AERO 53 MPH E   RMY 57

12/22 morning low temp: 33F; the normal low is now 22F

DAILY RECORDS FOR DECEMBER 2012
None so far.

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

RECORDS FOR DECEMBER 22
HIGH 62 IN 1994
LOW -5 IN 1921
PRECIP 1.52 INS. IN 1975
SNOWFALL 8.8 INS. IN 1975
PEAK GUST 62 MPH WNW IN 1998

RECORDS FOR DECEMBER 23
HIGH 62 IN 1990
LOW -1 IN 1989
PRECIP 1.70 INS. IN 1947
SNOWFALL 11.9 INS. IN 1947
PEAK GUST 67 SSE IN 2004

TODAY'S REPORT PREPARED BY: Mike Iacono, Jonathan O'Brien, Peter Volpe