BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, JANUARY 4, 2015   
ALL TIMES ARE IN EASTERN STANDARD TIME
 
STORM TO OUR WEST BRINGS SNOW, SLEET, AND RAIN
 
Clouds thickened during the day yesterday, and light snow began to fall by
late afternoon and evening.  Snow transitioned to sleet and then rain during
the night, as the temperature rose to 41F by the predawn hours.  At the
7:00 A.M. observation, a slushy half inch of snow remained, but the storm
total is estimated to be 2.5 inches based off data from yesterday evening,
and this number will be finalized in the coming days.  0.98 inches of
melted precipitation were recorded at the 7:00 A.M. observation as well.
 
Unsettled weather has continued today, with the summit stuck in heavy fog
all day and additional light rainfall totaling 0.05 inches.  After the
temperature rose to 41F in the early morning hours, it fell back, and we
remained in the low-mid 30s for much of the morning before the temperature
started rising before noon.  By the 1:00 observation we had risen back up
to 39F.  The wind has shifted from the NW this morning to the S this
afternoon, which is helping to usher in warmer air.  The speed of the wind
has increased as well, with gusts up to 25mph.
 
The corrected mean wind speed for December 2014 of
12.2 mph was the lowest on record for the month, and
the annual mean wind speed for 2014 of 12.3 mph was
the third lowest on record.    
 
SOME OF THE DECEMBER 2014 PRELIMINARY STATS
 
TEMPERATURE:  Deg. F
Av. Max. 42.0
Av. Min. 29.3
MEAN     35.7 [+4.3]
24-hour corrected mean: 35.5
Max. temp: 63 deg. Dec.  1
Min. temp: 14 deg. Dec. 31
Total heating degree day units:   901 [-135]
Total heating degree day units
for the season beginning July 1: 2060 [-245]
 
PRECIPITATION: Ins.
Total: 7.21 [+2.32]
Greatest in 24 hours;
Snowfall:  2.3 [-11.1]
Seasonal: 11.0 [-5.0 ]
 
WIND:
Av. uncorrected wind speed: 11.8 MPH
Av.   corrected wind speed: 12.2 MPH
Prevailing wind direction: W @ 14% 
 
SUNSHINE:
Astronomical total minutes:   5880/16999 or 35%
Campbell-Stokes card minutes: 5688/16470 or 35%
 
Today's Observations:
 
7 A.M.
Weather: Sky obscured by dense fog with very light drizzle    
Temperature: 35F; Dew Point: 35F; Wind: NNW at 8 kts
Sea-level pressure: 29.93 ins. Hg, falling then steady                      
Visibility: 1/8 mile, dense fog and light drizzle
6-hr max temp: 41F
6-hr min temp: 35F
6-hr precip. (ASOS): 0.20 ins
24-hr precip.: 0.98 ins
24-hr snowfall: 2.5 ins
Snow depth: 1 inch
BHO SA 1155 W3 X 1/8L-F 137/35/35/3308/993/ PCPN VRY LGT
NEW SNW PST 24 HRS 2.5 INS/ 8//// 4/001 56011 ASOS 60020
ASOS 70097 MANUAL 70098 10041 20035

10 A.M.
Weather: Sky obscured with dense fog 
Temperature: 33F; Dew Point: 33F; Wind: W at 4 kts,
Wind: Light and variable
Sea-level pressure: 29.91 ins. Hg, steady then falling
Visibility: 1/16 mile, dense fog
3-hr precip.: 0.04 ins
BHO SA 1455 W3 X 1/16F 129/33/33/2605/991/ WND LGT AND VRB/ 8////
58008 ASOS 60004 MANUAL 60004
 
1 P.M.
Weather: Sky obscured by dense fog, stratus fractus drifting over summit
Temperature: 39F; Dew Point: 39F; Wind: S at 12 kts,
Sea-level pressure: 29.76 ins. Hg, falling then falling more slowly
Visibility: 0 miles, dense fog
6-hr max temp: 39F
6-hr min temp: 33F
6-hr precip.: 0.05 ins
BHO SA 1755 W2 X 0F 079/39/39/1812/976/ STFRA DRFTG OVR SMT/ 8////
56050 ASOS 60006 MANUAL 60005 10039 20033
 
SUMMARY FOR SATURDAY, JANUARY 3, 2015
 
TEMPERATURE (DEGREES F)
MAX.....34   NORMAL.....35
MIN.....21   NORMAL.....18
MEAN....28   NORMAL.....26
 
DEPARTURE FROM 30-YEAR NORMAL..........................+2
TOTAL DEPARTURE FOR THE MONTH..........................+5 [+1.5 DEGREES/DAY]
 
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............37  DEPARTURE...........-2
TOTAL HEATING UNITS FOR THE MONTH.............110  DEPARTURE...........-5    
TOTAL HEATING UNITS FOR THE SEASON...........2177  DEPARTURE.........-243
TOTAL HEATING UNITS LAST SEASON TO DATE......2434  DIFFERENCE........-257
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..................25  SE  AT   8:44 P.M. 
                   ASOS.......................25  SE  AT   8:44 P.M. 
                   DAVIS......................23  SE  AT   8:43 P.M. RMY 26
FASTEST MILE FOR YESTERDAY....................17 ESE  AT  11:54 P.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE.................20 ESE  AT  11:38 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE................16 E    AT   4:39 P.M. 
AVERAGE WIND SPEED AND DIRECTION.............8.8 ESE
                   ASOS......................9.2   
                   DAVIS.....................7.5 E [080 degrees]                
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.98  DEPARTURE.....+0.83
                         ASOS..............0.97
TOTAL PRECIPITATION FOR THE MONTH..........0.98  DEPARTURE.....+0.54
                         ASOS..............0.97 
TOTAL PRECIPITATION FOR THE YEAR...........0.98  DEPARTURE.....+0.54
                         ASOS..............0.97 
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........2.5  DEPARTURE......+1.9
TOTAL SNOWFALL FOR THE MONTH................2.5  DEPARTURE......+0.8
TOTAL SNOWFALL FOR THE SEASON..............13.5  DEPARTURE......-6.1 
 
PRELIMINARY CLIMATE SUMMARY FOR DECEMBER-JANUARY CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY GUST
RMY:  R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized
 
12/1  63/37/50/+13/0.01/0.0/391/70             28 WNW RMY 31
12/2  37/30/34/-2/0.10/T/000/00                26 E   RMY 29
12/3  49/34/42/+6/0.31/0.0/000/00              40 W   RMY 43
12/4  41/27/34/-1/0.00/0.0/505/91              29 WNW RMY N/A
12/5  42/23/33/-2/0.12/0.0/382/69              21 E   RMY 22
12/6  43/36/40/+5/0.99/0.0/000/00              25 NNW RMY N/A
12/7  36/18/27/-7/0.15/0.0/193/35              31 N   RMY 34
12/8  25/16/21/-13/0.01/0.1/000/00             24 N   RMY N/A
12/9  48/25/37/+3/3.23/0.0/000/00              48 ENE RMY 52
12/10 47/35/41/+8/0.42/0.0/000/00              35 NNE RMY 37
12/11 35/29/32/-1/0.05/0.5/000/00              27 SW  RMY 27 
12/12 36/26/31/-2/0.00/0.0/230/42              23 WNW RMY 25
12/13 40/27/34/+2/0.00/0.0/191/35              28 NW  RMY 28
12/14 43/28/36/+4/0.00/0.0/377/69              20 NW  RMY 20
12/15 41/28/35/+3/0.00/0.0/535/98              17 NW  RMY 17
12/16 42/33/38/+7/T/T/011/02                   17 E   RMY N/A
12/17 45/37/41/+10/0.43/0.0/000/00             27 W   RMY N/A
12/18 41/32/37/+6/0.02/T/213/39                35 WNW RMY 38  
12/19 34/25/30/0/0.00/0.0/000/00               26 NW  RMY 29
12/20 32/24/28/-2/0.11/1.0/164/30              21 NNE RMY 23
12/21 31/29/30/+0/0.08/0.7/000/00              20 NNE RMY 22
12/22 42/29/36/+7/0.01/0.0/038/07              23 E   RMY N/A
12/23 44/39/42/+13/0.31/0.0/000/00             28 ENE RMY 30
12/24 61/40/51/+22/0.63/0.0/000/00             32 SSW RMY 41
12/25 61/41/51/+23/0.21/0.0/213/39             37 W   RMY 43
12/26 47/35/41/+13/0.00/0.0/540/99             24 WSW RMY 28
12/27 50/35/43/+15/0.00/0.0/519/95             21 SSW RMY N/A
12/28 49/35/42/+14/0.02/0.0/038/07             31 W   RMY 36
12/29 41/26/34/+7/0.00/0.0/470/86              23 WNW RMY 23
12/30 27/16/22/-5/0.00/0.0/470/86              22 NW  RMY N/A 
12/31 28/14/21/-6/0.00/0.0/400/73              23 W   RMY N/A
 
1/1   31/18/25/-2/0.00/0.0/.../..              29 SSW RMY 30
1/2   37/26/32/+5/0.00/0.0/.../..              35 WSW RMY 38
1/3   34/21/28/+2/..../.../.../..              25 SE  RMY 26  
 
1/4 morning low temp: 33F since midnight; normal low is now 18F
 
DAILY RECORDS FOR DECEMBER 2014:
     
-DAILY PRECIPITATION RECORD FOR DECEMBER 9 2014
      Old record of 1.51 inches set in 1952,
      replaced with new record of 3.23 inches.
 
-DAILY TEMPERATURE RECORD FOR DECEMBER 24 2014
        Old record of 58F set in 1996,
        replaced with new record of 61F.
 
DAILY RECORDS FOR JANUARY 2015
None so far.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):    
 
RECORDS FOR JANUARY 4
HIGH 60F IN 2000
LOW -8F IN 1904, 1981
PRECIP 1.79 INS. IN 1982
SNOW 8.6 INS. 1923, 1941
PEAK GUST 84 MPH S IN 1982
 
RECORDS FOR JANUARY 5
HIGH 61F IN 2007
LOW -9F IN 1981
PRECIP 0.98 INS. IN 1993
SNOW 4.5 INS. IN 1891
PEAK GUST 70 MPH WNW IN 1959
 
TODAY'S REPORT PREPARED BY: Jonathan O'Brien