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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, APRIL 2, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHT SNOW BEGINS BEFORE 7:00 A.M AND CONTINUES
THROUGHOUT THE DAY....

Snow began this morning around 6:40 A.M. and ended
today around 1:20 P.M. We have measured a total of 
1.6 ins. by 1:00 P.M.
Visibility decreased down to 1 mile in the middle of 
the day when humidity was the highest and snow was the 
heaviest. Once the snow began to clear visibility then 
increased back to 30 miles by 1:00 P.M. 
After an 8 degree above seasonable 58F yesterday, we 
are back to below seasonable temperatures here on 
Great Blue Hill. So far today we have a max of 34F, 
which is 16 degrees below the daily normal of 50F. 
Overnight low temperatures have returned to close to 
normal with a low of 31F since midnight. The daily 
normal is 32F. The wind has been very light and 
variable today.  

PRELIMINARY STATS FOR MARCH 2018
 
TEMPERATURE, Deg. F
Avg. Max. 41.2 [-3.1]
Avg. Min. 27.9 [+1.3]
Mean      34.6 [-0.9]
24-hour corrected mean: 33.9
Max. for month: 62F on 30th
Min. for month: 10F on 18th
 
HEATING DEGREE DAYS
Total heating units:   941  [+25]
Total for the season: 4063 [-421]
Total for last season: 4902

PRECIPITATION, Inches
Total: 8.69 [+3.29]
Greatest in 24 hrs: 3.47 on the 2nd 

SNOWFALL, Inches
Total: 45.5 [+32.8]
Greatest in 24 hrs: 23.0 in. on 13th
 
WIND, mph
Avg. uncorrected wind speed: 13.9
Avg. corrected wind speed: 14.3
Prevailing wind direction: NW at 14%
Peak gust and direction: 73 NNE on 2nd
 
SUNSHINE:
Campbell-Stokes card minutes: N/A
Astronomical total minutes: N/A

Blue Hill Observatory Greatest March Snowfall Totals, 
Inches (1885-2018)

1) 52.0 in 1956
2) 45.5 in 2018 
3) 42.2 in 1916
4) 41.4 in 2001
5) 41.0 in 1967
6) 37.8 in 2013
7) 35.5 in 1993

BHO Greatest March Monthly Precipitation, 
inches (1885-2018):

1) 18.81 in 2010
2) 13.07 in 2001
3) 10.96 in 1968
4) 10.02 in 1983
5) 9.53 in 1953
6) 9.00 in 1984
7) 8.72 in 1993
8) 8.69 in 2018
9) 8.09 in 1956
10) 7.98 in 1994

Today's Observations:

7 A.M.
Weather: Light snow, overcast stratus 
Temperature: 33F; Dew Point: 22F; Wind: E at 1 kts,
Wind: Light and variable, direction estimated 
Sea-level pressure: 30.14 ins. Hg, falling then rising     
Visibility: 30 miles, except NE-SSE 50 miles 
6-hr Max temp: 33F
6-hr Min temp: 32F
24-hr precip:  Trace
24-hr snowfall: Trace
Snow depth: 0 in.
BHO SA 1155 E35 OVC 30S- 205/33/22/E9001/014/ NEW SNW PST 
24 HRS TRACE S-B40 VSBY 50 NE-SSE DSNT FG ALQDS WND L/V/ 
8/6// 53014 10033 20032

10 A.M.
Weather: Light snow, overcast nimbostratus 
Temperature: 30F; Dew Point: 29F; Wind: W at 2 kts,
Wind: Light and variable, direction estimated 
Sea-level pressure: 30.14 ins. Hg, falling then rising 
Visibility: 1 mile 
3-hr precip: 0.10 ins. 
3-hr snowfall: 1.6 ins. 
BHO SA 1455 E5 OVC 1S-F 208/30/29/E2702/014/ NEW SNW 
PST 3 HRS 1.6 INS SUN DMLY VSBL WND L/V/ 8/6// 52003 
MANAUL 6010/ ASOS 60010
  
1 P.M.
Weather: Very light snow, broken stratus fractus,
broken stratus 
Temperature: 34F; Dew Point: 32F; Wind:  NW at 4 kts,
Wind: Light 
Sea-level pressure: 30.10 ins. Hg, falling, then more slowly
Visibility: 30 miles, distant fog in all directions 
6-hr Max temp: 34F
6-hr Min temp: 30F
6-hr precip: 0.13 ins.
6-hr snowfall: 1.6 ins. 
Snow depth: 0 ins.
BHO SA 1755 E12 BKN 18 BKN 30S- 194/34/32/3104/010/ NEW 
SNW PST 6 HRS 1.6 INS PCPN VRY LGT DSNT FG ALQDS WND LGT/ 
8/6// 56014 MANUAL 6013/ ASOS 60013 10034 20030

SUMMARY FOR SUNDAY, APRIL 1, 2018

TEMPERATURE (DEGREES F)
MAX.....58   NORMAL.....50
MIN.....33   NORMAL.....32
MEAN....46   NORMAL.....41

DEPARTURE FROM 30-YEAR NORMAL...........................+5
TOTAL DEPARTURE FOR THE MONTH...........................+5 [+4.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............19   DEPARTURE..........-5
TOTAL HEATING UNITS FOR THE MONTH.............19   DEPARTURE..........-5
TOTAL HEATING UNITS FOR THE SEASON..........5082   DEPARTURE........-426
TOTAL HEATING UNITS LAST SEASON TO DATE.....4934   DIFFERENCE.......+148

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................45 SSW AT 4:58 A.M.  
                   AERO........................43 SSW AT 4:52 A.M.
                   ASOS........................45 SSW AT 4:59 A.M.
                   DAVIS.......................43 M   AT 4:58 A.M ** RMY N/A
FASTEST MILE FOR YESTERDAY.....................30 SSW AT 5:00 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................32 S   AT 5:00 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................30 M   AT 5:00 A.M.**
AVERAGE WIND SPEED AND DIRECTION.............19.7 SSW
                   ASOS......................18.7
                   DAVIS.....................17.5 

** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.17
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........0.00  DEPARTURE......-0.17
                         ASOS..............0.00  
TOTAL PRECIPITATION FOR THE YEAR..........18.80  DEPARTURE......+4.81
                         ASOS.............20.24

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.2
TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE........-0.2
TOTAL SNOWFALL FOR THE SEASON..............90.2  DEPARTURE.......+30.2

PRELIMINARY CLIMATE SUMMARY FOR MARCH 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

3/01 61/37/49/+18/0.00/0.0/378/56    39 ENE AERO 37 ENE RMY N/A 
3/02 40/32/36/+5/3.47/0.7/000/00     73 NNE AERO 70 NNE RMY N/A
3/03 40/32/26/+4/T/T/034/05          52 NNE AERO 50 NNE RMY 49
3/04 39/34/37/+5/T/T/000/00          36 NNE AERO 32 NNE RMY 32 
3/05 40/29/35/+3/0.12/1.2/261/38     40 NE  AERO 39 NE  RMY 40
3/06 34/29/32/0/0.00/0.0/062/09      20 N   AERO 16 N   RMY N/A
3/07 35/31/33/0/0.49/10.0/000/00     52 ENE AERO 53 ENE RMY 50 
3/08 34/28/31/-2/0.67/5.0/000/00     44 NNE AERO 47 NNE RMY N/A
3/09 36/24/30/-3/T/T/265/38          28 W   AERO 26 W   RMY N/A 
3/10 37/28/33/0/0.00/0.0/343/49      38 WNW AERO 38 WNW RMY 41
3/11 42/26/34/0/0.00/0.0/583/83      28 NW  AERO 26 NW  RMY 29
3/12 39/26/33/-1/T/T/155/22          36 ENE AERO 33 ENE RMY N/A
3/13 35/26/31/-3/2.20/23.0/000/00    60 N   AERO 60 N   RMY 64
3/14 36/24/30/-5/0.00/0.0/470/66     38 WSW AERO 38 WSW RMY 41
3/15 40/29/35/0/..../.../422/59      44 W   AERO 44 W   RMY 44
3/16 35/23/29/-6/0.00/0.0/308/43     41 NW  AERO 41 NW  RMY 45
3/17 40/15/28/-8/0.00/0.0/533/74     46 W   AERO 45 W   RMY 49
3/18 31/10/21/-15/0.00/0.0/694/96    39 NW  AERO 38 NW  RMY 40
3/19 35/13/24/-12/0.00/0.0/704/97    32 WNW AERO 32 WNW RMY 34
3/20 40/18/29/-8/0.00/0.0/372/51     23 NW  AERO 21 NW  RMY N/A
3/21 35/31/33/-4/..../.../000/00     43 NE  AERO 44 NE  RMY N/A
3/22 39/30/35/-2/..../.../000/00     28 NNW AERO 26 NNW RMY 30
3/23 44/28/36/-2/0.00/0.0/.../..     21 NNW AERO 18 NNW RMY 21
3/24 45/32/39/+1/T/T/.../..          23 NE  AERO 21 NE  RMY N/A
3/25 36/29/33/-5/0.18/1.8/.../..     35 NNE AERO 30 NNE RMY 33
3/26 38/27/33/-6/0.00/0.0/.../..     33 NE  AERO 26 NE  RMY 30
3/27 44/25/35/-4/0.00/0.0/.../...    24 NE  AERO 17 NE  RMY 20
3/28 55/33/44/+5/0.01/0.0/.../..     21 SSW AERO 14 SSW RMY 18 
3/29 55/39/47/+7/T/0.0/.../..        24 SSE AERO 21 SSE RMY N/A
3/30 62/42/52/+12/0.08/0.0/.../..    32 NW  AERO 30 NW  RMY N/A
3/31 56/35/46/+5/T/0.0/.../..        37 NW  AERO 36 NW  RMY N/A

DAILY RECORDS FOR MARCH 2018

3/02/18: NEW DAILY RECORD MAXIMUM PRECIPITATION OF 3.47 INS.
         PREVIOUS RECORD WAS 2.15 INS. SET IN 1983

3/13/18: NEW DAILY RECORD MAXIMUM SNOWFALL OF 23.0 INS.
         PREVIOUS RECORD WAS 10.0 INS. SET IN 1993

3/13/18: NEW MONTHLY RECORD MAXIMUM DAILY SNOWFALL OF 23.0 INS.
         PREVIOUS RECORD WAS 18.0 INS. SET ON 8 MARCH 2013

PRELIMINARY CLIMATE SUMMARY FOR APRIL 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

4/01 58/33/46/+5/..../0.0/.../..   45 SSW AERO 43 SSW RMY N/A  

4/2 Low temp since midnight is 31F; normal low is now 33F

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

RECORDS FOR APRIL 2
HIGH 77 IN 1967
LOW 14 IN 1919
PRECIP 1.83 IN. IN 1970
SNOWFALL 13.0 IN. IN 1887
PEAK GUST 76 MPH SSW IN 1970

RECORDS FOR APRIL 3
HIGH 76 IN 1892
LOW 16 IN 1894
PRECIP 2.18 IN. IN 1990
SNOWFALL 8.0 IN. IN 1915
PEAK GUST 83e MPH NW IN 1977 [RECORD FOR MONTH]

TODAY'S REPORT PREPARED BY: K.A. Geagan