BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, DECEMBER 8, 2009
ALL TIMES ARE IN EASTERN STANDARD TIME
 
SUNSHINE RETURNS TODAY AFTER THE
CLOUDY SKIES OF YESTERDAY WHILE
SLIGHTLY COLDER THAN NORMAL TEMPERATURES
CONTINUE WITH WEST WINDS   
 
Except for high clouds, which prevented bright
sunshine for the first 20 minutes or so after
sunrise, today has been completely sunny with
temperatures rising into the upper 30's or a
few degrees less cold than yesterday.  Clouds
prevailed yesterday with only about an hour of
sunshine, all of it coming during the morning.
Three consecutive days have had minimum temp-
erature readings of 25F slightly under the normal
now of 27F.
 
Today's observations:
 
7 A.M.
Weather: Clear, cirrus, dense cirrus layer along horizon to
the distant east thru south-southwest 
Temperature: 26F, Dew point: 23F, Wind: WNW at 14 kts
Sea-level pressure: 30.21 inches Hg, rising
Visibility: 15 miles, thin fog, hazy all quadrants
6-hour minimum temp: 25F
24-hour precipitation: 0.00 inches
24-hour snowfall: 0.0 inches
Total snow depth: 3 inches
BHO SA 1155 CLR 15 229/26/23/2914/021/ CI/DENS CI LYR DSNT E-SSW
THN FG HAZY/ 8/002 4/003 53025 10028 20025
 
10 A.M.
Weather: Clear, SKC  
Temperature: 33F, Dew point: 23F, Wind: WNW at 11 kts
Sea-level pressure: 30.28 inches Hg, rising
Visibility: 20 miles, hazy
BHO SA 1455 CLR 20 255/33/23/3011/028/ HAZY/ 51026
 
1 P.M.
Weather: Clear, few cumulus fractus forming east thru south thru
southwest, cirrus distant WNW-NNW  
Temperature: 37F, Dew point: 21F, Wind: W at 11 kts,
Wind Direction variable WSW to NW, gust 21 kts past hour
Sea-level pressure: 30.27 inches Hg, falling 
Visibility: 30 miles, light haze
6-hour maximum temp: 37F
BHO SA 1755 CLR 30 250/37/21/2711/027/ FEW CUFRA FRMG E-SW CI 
DSNT WNW-NNW LGT HZ WND 24V31 GST TO 21 KTS PST HR/ 8/101 58006 
10037 20026 

WEATHER SUMMARY FOR MONDAY, DECEMBER 7
 
TEMPERATURE (DEGREES F)
MAX.....36     NORMAL.....41
MIN.....25     NORMAL.....27
MEAN....31     NORMAL.....34
 
DEPARTURE FROM 30-YEAR AVERAGE.............-3
TOTAL DEPARTURE FOR THE MONTH.............+31  [+4.2 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............34    DEPARTURE........+3
TOTAL HEATING UNITS FOR THE MONTH...........179    DEPARTURE.......-31
TOTAL HEATING UNITS FOR THE SEASON.........1339    DEPARTURE......-160
TOTAL HEATING UNITS LAST SEASON TO DATE....1446    DIFFERENCE.....-107
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............22 WSW AT 12:04 A.M.   
                   AEROVANE..............20 WSW AT 12:04 A.M. 
                   ASOS..................20 W   AT 11:07 P.M.    
                   DAVIS.................20 W   AT 10:55 P.M.  
THE FASTEST MILE FOR YESTERDAY...........15 WSW AT 10:26 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE............15 WSW AT 10:27 P.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE...........15 W   AT 11:23 P.M.  
AVERAGE WIND SPEED AND DIRECTION....... 8.7 SSW  
                   ASOS.................8.3
                   DAVIS................8.0 SW [220 DEG]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00   DEPARTURE....-0.15 
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.97   DEPARTURE....+0.92
                         ASOS..............2.07
TOTAL PRECIPITATION FOR THE YEAR..........51.54   DEPARTURE....+3.83
                         ASOS.............52.83
                 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........5.3  DEPARTURE.....-0.3
TOTAL SNOWFALL FOR THE MONTH................5.3  DEPARTURE.....+3.6
TOTAL SNOWFALL FOR THE SEASON...............8.3  DEPARTURE.....+3.7
                                               
PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2009 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 when significant
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
12/1  41/28/35/-1/0/0/497/89       29 NW 
12/2  51/33/42/+6/0.08/0/345/62    30 SSE
12/3  67/47/57/+22/1.01/0/428/77   69 SSE  AERO 73 SSE *
12/4  52/40/46/+11/0/0/488/88      26 W
12/5  42/30/36/+1/0.79/4.7/000/00  36 N
12/6  33/25/29/-5/0.09/0.6/.../..  36 NW
12/7  36/25/31/-3/0/0/.../..       22 WSW
 
* highest wind gust of the year to date
 
12/8  our morning low temp: 25F, the normal low is now 26F
 
NEW DAILY RECORD FOR DECEMBER 2009
12/3 NEW RECORD HIGH MAXIMUM TEMPERATURE of 67F;
     surpasses previous record of 61F in 1932, 1950.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
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
 
RECORDS FOR DECEMBER 9
HIGH 68 IN 1966
LOW -14 IN 1902
PRECIP 1.52 INS. IN 1956
SNOWFALL 10.8 INS. IN 2005
PEAK GUST 66 SE IN 1973
 
TODAY'S REPORT PREPARED BY: Robert Skilling