BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, DECEMBER 4, 2006 
 
FIRST SNOWFALL OF THE SEASON 3.2 INCHES
 
Precipitation began as some very light rain at 4:35 a.m.  
this morning but soon changed to all snow here at the 
summit by around 6 a.m. Snow fell at a rate of an inch
per hour starting about 6:30 a.m. and continuing until
around 8:30 a.m. The snow was sticky and wet and stuck 
to everything with very light winds occurring thoughout
the event. Measurements were easily made on our snow 
boards with so little wind. While 3.2 inches actually
fell here, there was even 1.5 inches or so on the pavement. 
  
The first snowflakes and first measurable snowfall 
of the season both occurred here this morning.  About
0.1 inch of snow had accumulated by 6:30 a.m. with 
precipitation all in the form of light snow at the 
summit and the temperature at 33 degrees. It dropped
from 35 degrees at 6 a.m. and 38 degrees at 2 a.m.
 
Today's observations:
 
7 A.M.
Weather: Moderate snow and dense fog
Temperature: 32F, Dew point: 32F, Wind: SSW at 02 kts 
Sea-level pressure: 29.98 inches Hg, falling 
Visibility: 1/8 mile
6-hourly min. 32F
6-hourly precip: 0.09 in. 
24-hourly precip: 0.09 in. 
6 and 24-hourly snowfall: 0.8 in. 
BHO SA 1155 W5 X 1/8SF 153/32/32/E2002/998/ SNOINC 1/1/ TOTAL 
NEW SNW PST 24 HRS 0.8 IN/ 8//// 58011 ASOS 60007 MANUAL 6009/ 
ASOS 60007 MANUAL 70009 10038 20032
 
10 A.M.    
Weather: Partial obscurement with fog and overcast stratocumulus
Temperature: 32F, Dew point: 32F, Wind: NW at 8 kt 
Sea-level pressure: 29.93 inches Hg, falling
Visibility: 1/8 mile 
3-hourly precip: 0.19 in. 
3-hourly snowfall: 2.4 ins. 
BHO SA 1455 –X 1/8F 135/32/32/3006/993/ F4 BRGHT SPTS IOVC 
SE10 TOTAL NEW SNW PST 3 HRS 2.4 INS/ 8/5// 57018 ASOS 60020
MANUAL 6019/  
 
1 P.M.     
Weather: Clear with few clouds 
Temperature: 35F, Dew point: 17F, Wind: WNW at 17G30 kts 
Sea-level pressure: 29.90 inches Hg, rising
Visibility: 70 miles
6-hourly max. temp. 35
6-hourly precip: 0.19 in. 
6-hourly snowfall: 2.4 ins. 
BHO SA 1755 CLR 70 124/35/17/2917G30/990/ FEW CU/SC ALQDS PK WND 
3032/20/ WND 26V32/ TOTAL NEW SNW PST 6 HRS 2.4 INS/ 8/400 55011 
ASOS 60020 MANUAL 6019/ 10035 20031                     
                              
WEATHER SUMMARY FOR SUNDAY, DECEMBER 3  
 
TEMPERATURE (DEGREES F)
MAX.....44   NORMAL.....43 
MIN.....29   NORMAL.....28   
MEAN....37   NORMAL.....35   
DEPARTURE FROM 30-YEAR NORMAL.......+ 2 
TOTAL DEPARTURE FOR THE MONTH.......+40 [+13.1 DEG/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..........28   DEPARTURE.....- 2
TOTAL HEATING UNITS FOR THE MONTH..........48   DEPARTURE.....-40 
TOTAL HEATING UNITS FOR THE SEASON.......1101   DEPARTURE....-276
TOTAL HEATING UNITS LAST SEASON TO DATE..1155   DIFFERENCE....-54
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...........29  S   AT 5:23 P.M.*          
                   AEROVANE............26  S   AT 5:23 P.M.*            
                   ASOS................26  S   AT 6:57 P.M.            
                   DAVIS...............28 WSW  AT 1:19 A.M.         
FASTEST MILE FOR YESTERDAY.............22  S   AT 5:24 P.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE..........22  S   AT 5:25 P.M.       
MAXIMUM 2-MINUTE DAVIS AVERAGE.........21  S   AT 7:38 P.M.             
AVERAGE WIND SPEED AND DIRECTION......12.9 S   
                   ASOS...............13.5        
                   DAVIS..............12.3 SW [220 deg.]
* last of several occurrences
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.09  DEPARTURE.....-0.06   
                         ASOS..............0.07
TOTAL PRECIPITATION FOR THE MONTH..........0.51  DEPARTURE.....+0.06 
                         ASOS..............0.52    
TOTAL PRECIPITATION FOR THE YEAR..........58.62  DEPARTURE....+11.65
                         ASOS.............58.14  
 
PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2006......CALENDAR DAY DATA
DATA REPORTED:
DATE  MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
12/1  65/59/62/+26/0.42/.../..  63 S    Aero 65 S
12/2  60/35/48/+12/0/.../..     47 W    Aero 44 W 
12/3  44/29/37/+2/0/.../../     29 S
 
12/4  morning low temp: 32 deg; normal now 28 deg. 
      morning melted precip: 0.09 in. thru 7 a.m. 
      morning snowfall 0.8 in. thru 7 a.m.        
 
      NEW DAILY RECORDS SO FAR THIS MONTH 
12/1- New daily and monthly record high minimum temperature 59;
      previous daily record 50 in 1908 and 1934, previous
      monthly record 53 on 4 and 6 December 1982 and on
      22 and 23 December 1990.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR DECEMBER 4
HIGH 67 IN 1998
LOW  -4 IN 1940
PRECIP 1.87 INCHES IN 1968
SNOWFALL 6.0 INCHES IN 1907
PEAK GUST 73 MPH WNW IN 1980
 
RECORDS FOR DECEMBER 5
HIGH 65 IN 2001
LOW  -1 IN 1926
PRECIP 2.86 INS. IN 1993
SNOWFALL 7.0 INS. IN 1907 and 1981
PEAK GUST 67 MPH WNW IN 1961, S IN 1973
 
TODAY'S REPORT By: Robert Skilling