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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, MARCH 21, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

OVERCAST AND WINDY WITH TEMPERATURES STAYING 
AROUND FREEZING ON GREAT BLUE HILL...

Today we observed overcast skies and a visibility increase
from 70 to 80 miles throughout the day. Moderate winds from 
the NE could be seen at all observation times, with gusts 
exceeding 30 miles per hour. The highest gust observed so 
far was 31 kts (36 MPH) just before 9:00 A.M.
The low temperature since midnight was 31F, which is
3 degrees above the normal of 28F. Temperatures stayed in 
the lower thirties between 7 A.M. and 1 P.M., only varying
a couple degrees. So far today we have reached a max of 33F, 
which is 13 degrees below the normal of 46F. 
Pressure has been showing a fairly steady decrease since 
10:00 A.M.

Today's Observations:

7 A.M.
Weather: Overcast altostratus
Temperature: 32F; Dew Point: 28F; Wind: NNE at 14G27 kts,
Peak Wind: 28 kts (32 MPH) NNE at 6:02 A.M. 
Sea-level pressure: 29.77 ins. Hg, falling steadily           
Visibility: 70 miles
6-hr Max temp: 33F
6-hr Min temp: 31F
24-hr precip:  0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 9 ins.
BHO SA 1155 E100 OVC 70 082/32/28/0414G27/977/ PK WND 0328/02/ 8/02/ 
4/009 57011 10033 20031 

10 A.M.
Weather: Overcast stratus
Temperature: 32F; Dew Point: 29F; Wind: NE at 14G27 kts,
Peak Wind: 29 kts (33 MPH) NNE at 9:18 A.M.  
Sea-level pressure: 29.79 ins. Hg, rising, then more slowly 
Visibility: 70 miles
3-hr precip:  0.00 ins.
3-hr snowfall: 0.0 ins.    
BHO SA 1455 E20 OVC 70 089/32/29/0414G27/979/ PK WND 0429/18/ 8/6// 
52007

1 P.M.
Weather: Overcast altostratus, few stratus fractus NE-SW
Temperature: 31F; Dew Point: 24F; Wind: NNE at 12G26 kts,
Peak Wind: 27 kts (31 MPH) NNE at 12:30 P.M.   
Sea-level pressure: 29.73 ins. Hg, falling, then more rapidly
Visibility: 80 miles
6-hr Max temp: 32F
6-hr Min temp: 31F
6-hr precip:   0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 9 ins.
BHO SA 1755 E100 OVC 80 069/31/24/0312G26/973/ FEW STFA NE-SW PK WND 
0327/30/ 8/62/ 4/009 58020 10032 20031
 
SUMMARY FOR TUESDAY, MARCH 20, 2018

TEMPERATURE (DEGREES F)
MAX.....40   NORMAL.....45
MIN.....18   NORMAL.....28
MEAN....29   NORMAL.....37

DEPARTURE FROM 30-YEAR NORMAL............................-8
TOTAL DEPARTURE FOR THE MONTH...........................-28 [-1.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............36   DEPARTURE..........+8
TOTAL HEATING UNITS FOR THE MONTH............659   DEPARTURE.........+33
TOTAL HEATING UNITS FOR THE SEASON..........4781   DEPARTURE........-413
TOTAL HEATING UNITS LAST SEASON TO DATE.....4581   DIFFERENCE.......+200

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................23 NW  AT 6:16  A.M.  
                   AERO........................21 NW  AT 12:04 A.M.
                   ASOS........................24 NW  AT 6:16  A.M.
                   DAVIS.......................22 M   AT 12:04 A.M ** RMY N/A
FASTEST MILE FOR YESTERDAY.....................19 NW  AT 12:14 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................17 NW  AT  5:51 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................17 M   AT 12:09 A.M.**
AVERAGE WIND SPEED AND DIRECTION..............8.5 NW
                   ASOS.......................8.3 
                   DAVIS......................7.8 ** 
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.19
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........7.97  DEPARTURE......+4.63
                         ASOS..............8.68  
TOTAL PRECIPITATION FOR THE YEAR..........18.08  DEPARTURE......+6.32
                         ASOS.............19.53

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........-0.4
TOTAL SNOWFALL FOR THE MONTH...............40.1  DEPARTURE.......+30.7
TOTAL SNOWFALL FOR THE SEASON..............84.8  DEPARTURE.......+28.3

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/.../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/..../.../000/00      52 ENE AERO 53 ENE RMY 50 
3/08 34/28/31/-2/..../.../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/.../..      28 NW  AERO 26 NW  RMY 29
3/12 39/26/33/-1/T/T/.../..          36 ENE AERO 33 ENE RMY N/A
3/13 35/26/31/-3/..../23.0/000/00    60 N   AERO 60 N   RMY 64
3/14 36/24/30/-5/..../.../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/.../...    46 W   AERO 45 W   RMY 49
3/18 31/10/21/-15/0.00/0.0/.../..    39 NW  AERO 38 NW  RMY 40
3/19 35/13/24/-12/0.00/0.0/.../..    32 WNW AERO 32 WNW RMY 34
3/20 40/18/29/-8/0.00/0.0/.../..     23 NW  AERO 21 NW  RMY N/A

3/21 Low temp since midnight is 31F; normal low is now 28F

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

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

RECORDS FOR MARCH 21
HIGH 81 IN 1921
LOW 2 IN 1885
PRECIP 2.67 INS. IN 1974
SNOWFALL 10.6 INS. IN 1958
PEAK GUST 72 MPH NE IN 1958

RECORDS FOR MARCH 22
HIGH 81 IN 2012
LOW 3 IN 1885
PRE 3.48 INS. IN 2001
SNOW 8.7 INS. 1967
WIND 84e MPH E IN 1977

TODAY'S REPORT PREPARED BY: Benjamin Turner and Kaitlin A. Geagan