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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, JANUARY 26, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

CLEAR AND COOL WEATHER WITH HIGH PRESSURE TODAY

Temperatures are continuing to run a little below normal today, making for
another chilly winter day. The morning low was 15F, our coldest reading since
1/15. The afternoon high so far is 30F. Clear skies and excellent visibility
have accompanied the cool temperatures, with visibility around 85 miles for
most of the day. Winds have been out of the WNW to NW and a bit breezy at times,
averaging 10-15mph with a couple gusts over 25mph this morning, though they
have calmed some this afternoon. The northwest flow has helped keep the air dry,
with dew points only slightly above zero and relative humidity values falling
near 30% this afternoon. A large high pressure center is passing over the region
today, contributing to high barometer readings. Our calculated sea level 
pressures approached 1040mb this morning, or near 30.70 ins. Hg, which are 
unusually high levels.

Today's Observations:

7 A.M.
Weather: Clear, few stratocumulus distant offshore NE-ESE, few
altocumulus S-SW, few cirrus mostly distant E
Temperature: 15F; Dew Point: 3F; Wind: WNW at 12 kts
Sea-level pressure: 30.61 ins. Hg, rising
Visibility: 70 miles
6-hr Max temp: 18F
6-hr Min temp: 15F
24-hr precip: 0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 0 ins.
BHO SA 1155 CLR 70 367/15/3/3012/061/ FEW SC DSNT OFFSHR NE-ESE 
FEW AC S-SW FEW CI MSTLY DSNT E/ 8/531 52025 10018 20015

10 A.M.
Weather: Clear, few stratocumulus distant offshore E-ESE
Temperature: 22F; Dew Point: 4F; Wind: NW at 11 kts
Sea-level pressure: 30.67 ins. Hg, rising, then more slowly 
Visibility: 85 miles 
3-hr precip: 0.00 ins.
3-hr snowfall: 0.0 ins. 
BHO SA 1455 CLR 85 386/22/4/3111/067/ FEW SC DSNT OFFSHR E-ESE/ 8/500 51019

1 P.M.
Weather: Clear, few cirrus ESE and distant WNW-NW
Temperature: 30F; Dew Point: 4F; Wind: W at 7 kts,
Wind: Direction variable WSW-NNW
Sea-level pressure: 30.64 ins. Hg, rising then falling
Visibility: 85 miles 
6-hr Max temp: 30F
6-hr Min temp: 15F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 0 ins. 
BHO SA 1755 CLR 85 376/30/4/2807/064/ FEW CI ESE AND DSNT WNW-NW 
WND 24V34/ 8/001 58010 10030 20015

SUMMARY FOR THURSDAY, JANUARY 25, 2018

TEMPERATURE (DEGREES F)
MAX.....29   NORMAL.....34
MIN.....17   NORMAL.....17
MEAN....23   NORMAL.....25

DEPARTURE FROM 30-YEAR NORMAL...........................-2
TOTAL DEPARTURE FOR THE MONTH...........................-2 [-0.1 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............42  DEPARTURE..........+2
TOTAL HEATING UNITS FOR THE MONTH............991  DEPARTURE..........+2
TOTAL HEATING UNITS FOR THE SEASON..........3113  DEPARTURE........-180
TOTAL HEATING UNITS LAST SEASON TO DATE.....2834  DIFFERENCE.......+279

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................35  WNW  AT  3:45 P.M. *
                   AERO.........................36  WNW  AT  1:15 P.M.
                   ASOS.........................37  NW   AT 10:35 A.M.
                   DAVIS........................36  M    AT  3:45 P.M.** RMY 41 
FASTEST MILE FOR YESTERDAY......................26  WNW  AT 10:35 A.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................26  NW   AT  3:34 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................26  M    AT  3:34 P.M.**
AVERAGE WIND SPEED AND DIRECTION..............13.4  WNW
                   ASOS.......................12.7 
                   DAVIS......................12.4
*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..........5.52  DEPARTURE......+1.98
                         ASOS..............6.07
TOTAL PRECIPITATION FOR THE YEAR...........5.52  DEPARTURE......+1.98
                         ASOS..............6.07

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.6
TOTAL SNOWFALL FOR THE MONTH...............19.3  DEPARTURE........+5.3
TOTAL SNOWFALL FOR THE SEASON..............28.6  DEPARTURE........-1.4

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/-24/0.00/0.0/538/98        30 NW  AERO 30 NW  RMY 31
1/02 15/-2/7/-20/0.00/0.0/402/73        26 W   AERO 25 W   RMY 26  
1/03 28/11/20/-6/0.00/0.0/430/78        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/-16/0.00/0.0/431/78        53 W   AERO 53 W   RMY 57
1/06 10/-2/4/-22/0.00/0.0/554/100       43 WSW AERO 47 WSW RMY 47
1/07 14/-8/3/-23/0.00/0.0/549/99        37 WNW AERO 35 WNW RMY N/A 
1/08 33/14/24/-2/0.02/T/006/01          40 S   AERO 40 S   RMY 42 
1/09 40/25/33/+7/T/T/356/64             37 W   AERO 35 W   RMY 33
1/10 36/20/28/+3/0.00/0.0/553/99        30 W   AERO 30 W   RMY N/A
1/11 50/32/41/+16/0.00/0.0/056/10       33 S   AERO 32 S   RMY 34
1/12 60/45/53/+28/..../0.0/011/02       56 S   AERO 56 S   RMY 55
1/13 60/17/39/+14/..../0.0/265/47       58 SSW AERO 60 SSW RMY 62
1/14 21/11/16/-9/0.00/0.0/350/62        30 NW  AERO 30 NW  RMY N/A
1/15 18/11/15/-10/0.02/0.5/000/00       23 NNW AERO 21 N   RMY 23
1/16 31/18/25/0/0.00/0.0/153/27         17 SSE AERO 15 SSE RMY N/A 
1/17 32/29/31/+6/0.23/2.3/.../00        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 34/17/26/+1/0.00/0.0/.../..        22 SSW AERO 20 SSW RMY N/A
1/20 45/27/36/+11/0.00/0.0/.../..       38 WSW AERO 37 WSW RMY 39 
1/21 47/34/41/+16/0.00/0.0/.../..       22 W   AERO 21 W   RMY N/A
1/22 37/34/36/+11/..../0.0/000/00       21 E   AERO 16 E   RMY N/A
1/23 55/33/44/+19/..../0.0/000/00       53 S   AERO 58 S   RMY 57 
1/24 37/22/30/+5/0.00/0.0/.../..        36 WNW AERO 35 WNW RMY 36 
1/25 29/17/23/-2/0.00/0.0/.../..        35 WNW AERO 36 WNW RMY 41 

1/26 Low temp since midnight is 15F; 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 26
HIGH 68F IN 1950 [RECORD FOR MONTH]
LOW -5F IN 1920
PRECIP 1.60 INS. IN 1958
SNOW 9.0 INS. IN 1898
WIND 90e MPH SE IN 1978

RECORDS FOR JANUARY 27
HIGH 63F IN 1974
LOW -12F IN 1924
PRECIP 1.59 INS. IN 1996
SNOWFALL 25.2 INS. IN 2015 [RECORD FOR MONTH]
PEAK GUST 91 MPH SSE IN 1996

TODAY'S REPORT PREPARED BY: Jonathan O'Brien