BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, DECEMBER 12, 2012
ALL TIMES ARE IN EASTERN STANDARD TIME
 
MUCH COLDER WITH SUNSHINE DIMMED BY HIGH CLOUDS TODAY
FIRST 11 DAYS OF DECEMBER 2012 ALMOST 7 DEGREES ON WARM SIDE
WHILE FIRST 11 DAYS OF DECEMBER 2011 AVERAGED +8 DEGREES
 
This afternoon our high temperature is only in the middle
30's while 24 hours it was in the mid-40's.
Temperatures fell from a mild 54 degrees at the start of
the day yesterday (midnight) to 30 degrees by midnight last
night and then on down to 26F this morning.  This was just
one degree above the normal low of 25F. Temperatures so
far this month are nearly a carbon copy of what we experienced
one year ago when the average for the first 11 days of December
was +8 degrees.  This year it's nearly +7 degrees.
 
Today's observations:
 
7 A.M.
Weather: Overcast dense cirrostratus, few small cumulus along and
offshore distant E-ESE, few altocumulus lenticularis NE-ESE,
thin spots in overcast SE, clear sky band/break in overcast
extending W-NNE
Temperature: 27F; Dew Point: 19F; Wind: NNW at 9 kts.
Sea-level pressure: 30.30 ins Hg, rising then more slowly 
Visibility: 60 miles, except 70 miles NW, light distant haze 
6-hour min. temp: 26F
24-hour precip: 0.01 in.
BHO SA 1155 E220 OVC 60 260/27/19/3309/030/ FEW SML CU ALG/OFFSHR 
DSNT E-ESE FEW ACSL NE-ESE DNS CS THN SPTS IOVC SE CLR SKY BND/BINOVC 
XTDNG W-NNE VSBY NW 70 LGT DSNT HZ/ 8/148 51028 MANUAL 70001 10029 20026
 
10 A.M.
Weather: High dense overcast cirrostratus/cirrus,
stratocumulus layer distant offshore NE-ESE, few cirrocumulus
and thin spots and small breaks in overcast SE-SW,
large break in overcast/clear sky band extending distant W
through vicinity of station NW-N thru distant NE
Temperature: 32F; Dew Point: 21F; Wind: NNW at 8 kts,
Wind: Direction variable WNW-N
Sea-level pressure: 30.36 ins Hg, rising then more slowly    
Visibility: 75 miles, light distant haze, thin smoke layer
along and above horizon W-NE 
BHO SA 1455 E220 OVC 75 282/32/21/3308/036/ SC LYR DSNT OFFSHR NE-ESE
FEW CC DSNT SE-SW DNS CI ALQDS THN SPTS IOVC/SML BINOVC DSNT SE-SW
LGE BINOVC/CLR SKY BND XTDNG DSNT W-VC NW-N-DSNT NE WND 29V01
THN K LYR ALG/ABV HRZN W-NE LGT DSNT HZ/ 8/502 51022 
 
1 P.M.
Weather: Scattered dense cirrus/cirrostratus layer and
broken dense cirrus/cirrostratus layer, halo, large clear
sky band extending distant WSW thru vicinity WNW-N thru
distant NNE, stratocumulus layer offshore distant ENE-E     
Temperature: 35F; Dew Point: 20F; Wind: WNW at 3 kts
Sea-level pressure: 30.34 ins Hg, falling slowly
Visibility: 60 miles, except 70 miles NW, thin distant smoke
layer along/above horizon W-NE, light distant haze
6-hour max. temp: 36F
6-hour min. temp: 27F
BHO SA 1755 200 SCT E220 BKN 60 274/35/20/2903/034/ SC LYR DSNT ENE-E 
OFFSHR ACSL DSNT ESE-SSW DNS CI LYR LGE CLR SKY BND XTDNG DSNT WSW-VC 
WNW-N-DSNT NNE HALO THN DSNT K LYR ALG/ABV HRZN W-NE LGT DSNT HZ 
VSBY NW 70/8/542 57008 10036 20027
 
WEATHER SUMMARY FOR TUESDAY, DECEMBER 11
 
TEMPERATURE (DEGREES F)
MAX.....54      NORMAL.....41
MIN.....30      NORMAL.....25
MEAN....42      NORMAL.....33
 
DEPARTURE FROM 30-YEAR NORMAL.....................+9
TOTAL DEPARTURE FOR THE MONTH....................+76 [+6.7 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............23    DEPARTURE.........-9
TOTAL HEATING UNITS FOR THE MONTH...........257    DEPARTURE........-76 
TOTAL HEATING UNITS FOR THE SEASON.........1407    DEPARTURE.......-188
TOTAL HEATING UNITS LAST SEASON TO DATE....1161    DIFFERENCE......+246
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...............25 W   AT 12:42 P.M. *
                   AERO....................25 W   AT 12:42 P.M.
                   ASOS....................24 W   AT 12:42 P.M.
                   DAVIS...................23 NW  AT  1:33 A.M. RMY N/A
THE FASTEST MILE FOR YESTERDAY.............18 WNW AT 12:44 P.M. *  
MAXIMUM 2-MINUTE ASOS AVERAGE..............17 WNW AT 12:43 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.............17 NW  AT  1:55 A.M.
AVERAGE WIND SPEED AND DIRECTION.........11.2 WNW
                   ASOS..................10.7
                   DAVIS..................9.7 WNW [290 deg]
* last of several occurrences....
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.01   DEPARTURE..........-0.15
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.11   DEPARTURE..........-0.70
                         ASOS..............1.13
TOTAL PRECIPITATION FOR THE YEAR..........35.98   DEPARTURE.........-14.35
                         ASOS.............36.02
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0    DEPARTURE..........-0.4
TOTAL SNOWFALL FOR THE MONTH...............0.8    DEPARTURE..........-2.8
TOTAL SNOWFALL FOR THE SEASON..............6.8    DEPARTURE..........+0.6    
 
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/.../..     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/.../..     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/.../..     25 W   AERO 25 MPH W   RMY 23
 
12/12 morning low temp: 26F; the normal low is now 25F
 
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 12
HIGH 67 IN 1979
LOW -3 IN 1988
PRECIP 3.94 INS. IN 1992
SNOWFALL 20.3 INS. IN 1960
PEAK GUST 75 MPH SSE IN 2008
 
RECORDS FOR DECEMBER 13
HIGH 60 IN 1984
LOW 0 IN 1893
PRECIP 1.45 INS. IN 1983
SNOWFALL 9.2 INS. IN 2007
PEAK GUST 81e WNW IN 1976
 
TODAY'S REPORT PREPARED BY: Robert Skilling