BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JANUARY 19, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

CALM AND SEASONABLE WEATHER TODAY

Thin fog and some clouds to the east made for a brilliant red sunrise 
this morning at Blue Hill. Considerable cloud cover lingered during 
the morning, but more sunshine has been observed early this afternoon. 
A weak disturbance brought some light snow to central New England 
overnight, but no precipitation has been observed here. Temperatures 
are running close to normal for this time of year today, with a 
morning low of 17F and a high through 1PM of 32F. Winds have been 
light again today, mainly from the west at 5-10mph. Today looks on 
track to be our fifth consecutive day with a peak wind gust under 
30mph, after this only happened twice the first two weeks of the 
month. A persistent thin fog and haze layer has limited visibility 
to 10-15 miles today.

Today's Observations:

7 A.M.
Weather: Scattered stratocumulus, scattered cirrus
Temperature: 18F; Dew Point: 14F; Wind: W at 11 kts
Sea-level pressure: 29.96 ins. Hg, rising then more slowly 
Visibility: 10 miles, thin fog 
6-hr Max temp: 19F
6-hr Min temp: 17F
24-hr precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 2 ins.
BHO SA 1155 30 SCT 250 SCT 10 147/18/14/2611/996/ THN FG/ 
8/501 4/002 51010 10019 20017

10 A.M.
Weather: Broken stratocumulus, broken altocumulus
Temperature: 25F; Dew Point: 18F; Wind: W at 8 kts,
Sea-level pressure: 29.99 ins. Hg, rising then steady
Visibility: 12 miles, thin fog
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins. 
BHO SA 1455 E35 BKN 150 BKN 12 155/25/18/2608/999/ THN FG/ 
8/55/ 51008

1 P.M.
Weather: Scattered stratocumulus, scattered cirrus, few 
cirrocumulus S-SW
Temperature: 32F; Dew Point: 20F; Wind: W at 8 kts
Sea-level pressure: 29.93 ins. Hg, steady then falling
Visibility: 12 miles, hazy
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
6-hr Max temp: 32F
6-hr Min temp: 18F
Snow depth: 2 ins.
BHO SA 1755 35 SCT 250 SCT 12 134/32/20/2708/993/ FEW CC S-SW 
HAZY/ 8/509 4/002 58021 10032 20018

SUMMARY FOR THURSDAY, JANUARY 18, 2018

TEMPERATURE (DEGREES F)
MAX.....29   NORMAL.....33
MIN.....16   NORMAL.....17
MEAN....23   NORMAL.....25

DEPARTURE FROM 30-YEAR NORMAL...........................-2
TOTAL DEPARTURE FOR THE MONTH..........................-63 [-3.7 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............42  DEPARTURE..........+2
TOTAL HEATING UNITS FOR THE MONTH............772  DEPARTURE.........+64
TOTAL HEATING UNITS FOR THE SEASON..........2894  DEPARTURE........-118
TOTAL HEATING UNITS LAST SEASON TO DATE.....2645  DIFFERENCE.......+249

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................24  NW   AT 3:12 P.M.*
                   AERO........................23  NW   AT 2:28 P.M.
                   ASOS........................24  NW   AT 2:29 P.M.
                   DAVIS.......................24  M    AT 2:29 P.M.** RMY 26 
FASTEST MILE FOR YESTERDAY.....................17  NW   AT 2:15 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE..................17  WNW  AT 2:29 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................17  M    AT 2:22 P.M.**
AVERAGE WIND SPEED AND DIRECTION..............10.0 WNW
                   ASOS.......................10.1
                   DAVIS......................9.1
*Last of several occurrences
**Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.14
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........4.19  DEPARTURE......+1.62
                         ASOS..............4.63
TOTAL PRECIPITATION FOR THE YEAR...........4.19  DEPARTURE......+1.62
                         ASOS..............4.63

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.5
TOTAL SNOWFALL FOR THE MONTH...............19.3  DEPARTURE........+9.2
TOTAL SNOWFALL FOR THE SEASON..............28.6  DEPARTURE........+2.5

PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

1/01 11/-5/3/-24/0.00/0.0/.../..        30 NW  AERO 30 NW  RMY 31
1/02 15/-2/7/-20/0.00/0.0/.../..        26 W   AERO 25 W   RMY 26  
1/03 28/11/20/-6/0.00/0.0/.../..        23 WSW AERO 20 WSW RMY N/A
1/04 28/18/23/-3/1.66/16.5/000/00       54 NNW AERO 60 NNW RMY 64
1/05 18/2/10/-16/0.00/0.0/.../..        53 W   AERO 53 W   RMY 57
1/06 10/-2/4/-22/0.00/0.0/.../..        43 WSW AERO 47 WSW RMY 47
1/07 14/-8/3/-23/0.00/0.0/.../..        37 WNW AERO 35 WNW RMY N/A 
1/08 33/14/24/-2/T/T/.../..             40 S   AERO 40 S   RMY 42 
1/09 40/25/33/+7/T/T/.../..             37 W   AERO 35 W   RMY 33
1/10 36/20/28/+3/0.00/0.0/.../..        30 W   AERO 30 W   RMY N/A
1/11 50/32/41/+16/0.00/0.0/.../..       33 S   AERO 32 S   RMY 34
1/12 60/45/53/+28/..../0.0/.../..       56 S   AERO 56 S   RMY 55
1/13 60/17/39/+14/..../0.0/.../..       58 SSW AERO 60 SSW RMY 62
1/14 21/11/16/-9/0.00/0.0/.../..        30 NW  AERO 30 NW  RMY N/A
1/15 18/11/15/-10/..../.../.../..       23 NNW AERO 21 N   RMY 23
1/16 31/18/25/0/0.00/0.0/.../..         17 SSE AERO 15 SSE RMY N/A 
1/17 32/29/31/+6/0.23/2.3/.../..        20 SE  AERO 17 SE  RMY N/A
1/18 29/16/23/-2/0.00/0.0/.../..        24 NW  AERO 23 NW  RMY 26 

1/19 Low temp since midnight is 17F; normal low is now 17F

DAILY RECORDS FOR JANUARY 2018

01/04/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 16.5 INS. 
          PREVIOUS RECORD WAS 8.6 INS. SET IN 1923 AND 
          TIED IN 1942 

01/07/18: DAILY RECORD LOW MINIMUM TEMPERATURE OF -8F,
          PREVIOUS RECORD OF -7F WAS SET IN 1896

01/12/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 45F,
          PREVIOUS RECORD OF 42F WAS SET IN 2017

          DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
          PREVIOUS RECORD OF 59F WAS SET IN 2017

01/13/18: DAILY RECORD HIGH MAXIMUM TEMPERATURE OF 60F,
          PREVIOUS RECORD OF 57F WAS SET IN 1890 AND
          TIED IN 1932 

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):      

RECORDS FOR JANUARY 19
HIGH 59F IN 1973
LOW -11F IN 1887
PRECIP 2.34 INS. IN 1936
SNOWFALL 10.5 INS. IN 1936
PEAK GUST 93e MPH WNW IN 1943

RECORDS FOR JANUARY 20
HIGH 59F IN 1951
LOW -9F IN 1901
PRECIP 1.95 INS. IN 1978
SNOWFALL 19.0 INS. IN 1978 
PEAK GUST 76e MPH NE IN 1978

TODAY'S REPORT PREPARED BY: Jonathan O'Brien