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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, DECEMBER 6, 2012
ALL TIMES ARE IN EASTERN STANDARD TIME

COLD AND GUSTY WNW-NW WINDS OVERNIGHT LAST NIGHT
NEW COLD AND DRY AIR MASS IN PLACE TODAY

Temperatures fell from a high of 56 degrees early yesterday morning to 31
by midnight last night accompanied by gusty WNW-NW winds up to 30-40 mph. 
Today sunny cold and dry weather is established and our high temperature
is falling short of 40 degrees.  The low of 25 degrees equals the lowest
so far this cold weather season.  Dew points are in the teens.  

Today's observations:
 
7 A.M.
Weather: Clear, stratocumulus layer along/offshore distant NNE-S 
Temperature: 25F; Dew Point: 16F; Wind: NW at 10 kts,
Wind: Direction variable WNW-N  
Sea-level pressure: 30.27 ins. Hg, rising
Visibility: 60 miles, light distant haze  
6-hour min. temp: 25F 
24-hour precip: 0.01 inch 
BHO SA 1155 CLR 60 252/25/16/3210/027/ SC LYR ALG HRZN DSNT NNE-S OFFSHR 
WND 29V35/ 8/500 53025 MANUAL 70001 ASOS 70001 10029 20025

10 A.M.   
Weather: Clear, stratocumulus layer offshore distant NE-SSE, 
few cirrus ESE and SSE and WSW-NNW
Temperature: 31F; Dew Point: 15F; Wind: NNW at 10 kts,
Wind: Direction variable WNW-NNE 
Sea-level pressure: 30.31 ins. Hg, rising then more slowly     
Visibility: 80 miles 
BHO SA 1455 CLR 80 265/31/15/3310/031/ SC LYR OFFSHR DSNT NE-SSE 
FEW CI ESE-SSE AND DSNT WSW-NNW WND 30V02/ 8/501 51013 
  
1 P.M.   
Weather: Thin scattered cirrus, few lower cirrus, cirrus except overhead
thru SE, stratocumulus layer offshore distant E-ESE  
Temperature: 37F; Dew Point: 15F Wind: WNW at 6 kts.
Sea-level pressure: 30.27 ins. Hg, falling steadily    
Visibility: 80 miles
6-hour max. temp: 37F 
6-hour min. temp: 25F
BHO SA 1755 300 –SCT 80 250/37/15/2906/027/ SC LYR OFFSHR DSNT 
E-ESE CI XCPT OVHD-SE FEW DSNT LWR CI/ 8/501 58015 10037 20025 

WEATHER SUMMARY FOR WEDNESDAY, DECEMBER 5

TEMPERATURE (DEGREES F)
MAX.....56      NORMAL.....43
MIN.....31      NORMAL.....27
MEAN....44      NORMAL.....35
 
DEPARTURE FROM 30-YEAR NORMAL.....................+9
TOTAL DEPARTURE FOR THE MONTH....................+35 [+6.8 DEGREE/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............21    DEPARTURE.........-9
TOTAL HEATING UNITS FOR THE MONTH...........111    DEPARTURE........-35  
TOTAL HEATING UNITS FOR THE SEASON.........1261    DEPARTURE.......-147
TOTAL HEATING UNITS LAST SEASON TO DATE....1019    DIFFERENCE......+242

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY..............38 WNW AT  5:03 P.M.  
                   AERO...................39 WNW AT  5:03 P.M. 
                   ASOS...................37 NW  AT  6:28 P.M.  
                   DAVIS..................36 W   AT  5:03 P.M. RMY 40
THE FASTEST MILE FOR YESTERDAY............26 WNW AT  6:36 P.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE.............26 WNW AT  6:37 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE............26 S   AT 12:42 A.M.  
AVERAGE WIND SPEED AND DIRECTION........18.3 WNW 
                   ASOS.................16.8
                   DAVIS................16.1 W  [270 deg]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.01   DEPARTURE..........-0.16
                         ASOS..............0.01
TOTAL PRECIPITATION FOR THE MONTH..........0.12   DEPARTURE..........-0.70
                         ASOS..............0.11
TOTAL PRECIPITATION FOR THE YEAR..........35.00   DEPARTURE.........-14.35
                         ASOS.............35.00

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0    DEPARTURE..........-0.3
TOTAL SNOWFALL FOR THE MONTH...............0.8    DEPARTURE..........-0.6
TOTAL SNOWFALL FOR THE SEASON..............6.8    DEPARTURE..........+2.8	

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/+6/0.00/0.0/000/00     32 SSW AERO 32 MPH SSW RMY 34
12/3  57/43/50/+14/0.00/0.0/.../..    31 NW  AERO 30 MPH NW  RMY 32
12/4  56/40/48/+13/0.03/0.0/.../..    37 S   AERO 39 MPH S   RMY 38 
12/5  56/31/44/+9/0.03/0.0/.../..     38 WNW AERO 37 MPH WNW RMY 40 

12/6  morning low temp: 25F; the normal low is now 27F

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 6
HIGH 70 IN 2001
LOW 5 IN 1901,1935
PRECIP 2.78 INS. IN 2003
SNOWFALL 17.0 INS. IN 2003
PEAK GUST 74 MPH NW IN 1981

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

TODAY'S REPORT PREPARED BY: Robert Skilling/Patrick Peters 
 
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