BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
  
DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, DECEMBER 22, 2007
ALL TIMES ARE IN EASTERN STANDARD TIME

PARTIAL SUNSHINE AND WARMER TODAY...
After a cold start in the low 20s, the temperature has
climbed to the mid-30s this afternoon.  It was still a
pretty scene on the summit this morning with the snow from
this week was still coating the trees due to the light
winds the last two days. There was still 17 inches of
snow on the summit this morning, but this is dropping
now in the warming temperature.   

Today's observations:

7 A.M.   
Weather: Overcast stratocumulus
Temperature: 24F, Dew point: 22F, Wind: NNW at 9 kts
Sea-level pressure: 30.61 inches Hg, rising
Visibility: 25 miles, hazy
6-hour min temp: 23F 
24-hour precip: trace 
24-hour snowfall: trace
Snow on ground: 17 inches 
BHO SA 1155 E25 OVC 25 365/24/22/3409/061/ HAZY/ 8/5// 
4/017 51007 10024 20023

10 A.M.
Weather: Overcast stratocumulus, few breaks overhead
Temperature: 28F, Dew point: 26F, Wind: NNW at 8 kts
Sea-level pressure: 30.62 inches Hg, rising
Visibility: 20 miles, hazy
BHO SA 1455 E25 OVC 20 368/28/26/3408/062/ FEW BINOVC OVHD 
HAZY WND LGT/ 8/5// 51003

1 P.M.
Weather: Broken stratocumulus, thin overcast cirrus
Temperature: 33F, Dew point: 30F, Wind: N at 6 kts
Sea-level pressure: 30.58 inches Hg, falling
Visibility: 15 miles, hazy
6-hourly max. temp: 33F  
BHO SA 1755 E35 BKN 200 –OVC 15 354/33/30/3506/058/ HAZY 
WND LGT/  8/501 56014 10033 20024


WEATHER SUMMARY FOR FRIDAY, DECEMBER 21

TEMPERATURE (DEGREES F)
MAX.....28    NORMAL.....37 
MIN.....22    NORMAL.....22
MEAN....25    NORMAL.....30
DEPARTURE FROM 30-YEAR NORMAL...........-5 
TOTAL DEPARTURE FOR THE MONTH.........-119 [-5.9 DEGREES/DAY] 

HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY............40  DEPARTURE.......+5 
TOTAL HEATING UNITS FOR THE MONTH...........800  DEPARTURE.....+124 
TOTAL HEATING UNITS FOR THE SEASON.........1880  DEPARTURE......-85
TOTAL HEATING UNITS LAST SEASON TO DATE....1582  DIFFERENCE....+298

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............25 N AT 2:46 A.M.  
                   AEROVANE.............25 N AT 2:34 A.M.   
                   ASOS................N/A  *  
                   DAVIS................21 N AT 2:46 A.M.   
FASTEST MILE FOR YESTERDAY............. 17 N AT 2:32 A.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE..........N/A  *  
MAXIMUM 2-MINUTE DAVIS AVERAGE..........15 N AT 2:47 A.M.  
AVERAGE WIND SPEED AND DIRECTION......10.1 NNW  
                   ASOS................N/A  *           
                   DAVIS...............7.1 NNW [335 deg]        
* ASOS WIND SYSTEM MALFUNCTIONED ON DEC 19.

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...trace  DEPARTURE....-0.15 
                         ASOS..............0.00 
TOTAL PRECIPITATION FOR THE MONTH..........4.69  DEPARTURE....+1.63
                         ASOS..............4.74  
TOTAL PRECIPITATION FOR THE YEAR..........43.53  DEPARTURE....-6.19
                         ASOS.............42.96   

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M........trace  DEPARTURE.....-0.4
TOTAL SNOWFALL FOR THE MONTH...............28.2  DEPARTURE....+21.5
TOTAL SNOWFALL FOR THE SEASON..............29.0  DEPARTURE....+19.4

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2007...CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available

12/1  33/15/24/-12/0/0/493/88       54 WNW 
12/2  24/15/20/-16/0.03/0.3/000/00  28 WNW 
12/3  38/23/31/-4/0.62/1.7/000/00   47 W 
12/4  27/17/22/-13/T/T/111/20       48 W       
12/5  29/17/23/-12/T/T/244/44       23 WNW
12/6  28/15/22/-12/0/0/554/100      31 WNW
12/7  34/21/28/-6/0.07/0.7/000/00   24 SSW
12/8  41/25/33/0/0/0/452/82         32 W
12/9  33/25/29/-4/0.08/T/000/00     16 NW  
12/10 30/26/28/-5/0.10/0/000/00     18 N 
12/11 36/22/29/-3/0.09/0/258/47     25 S
12/12 44/22/36/+4/T/0/88/16         39 W
12/13 29/20/25/-7/1.08/9.2/000/00   24 ENE
12/14 37/20/29/-2/0.02/0.2/038/07   28 WSW
12/15 28/15/22/-9/0/0/.../..        31 WNW  
12/16 43/23/33/+2/1.62/8.5/000/00   54 NE 
12/17 32/15/24/-7/0/0/.../..        62 W
12/18 31/10/21/-9/0/0/.../..        20 W 
12/19 38/24/31/+1/.../.../.../..    19 E
12/20 33/26/30/0/.../../000/00      24 NNW
12/21 28/22/25/-5/.../../000/00     25 N

12/22 morning low temp. 23F; our normal low is now 22F
      total snow and ice on the ground 17 inches  

NEW DAILY RECORDS FOR DECEMBER 2007: 
Dec 13: Record daily snowfall of 9.2 inches surpasses previous 
record of 9.0 inches in 1902.
Dec.16: Record daily snowfall of 8.5 inches surpasses previous
record of 7.0 inches in 1896. 

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

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