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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, MAY 2, 2016 
ALL TIMES ARE IN EASTERN STANDARD TIME

COOL TEMPS, FOG, AND LIGHT DRIZZLE AS LOW PRESSURE MOVES
THROUGH AREA

Temperatures reached a minimum of 39F just before midnight
last night as fog moved in.  They were slow to warm, reaching
a maximum of only 48F by the 1:00 PM EST observation, 15F 
below average.  Visibility was poor all day due to thick fog.
Light drizzle increased to rain showers in the early afternoon
giving 0.29 in. of precipitation by 1:00 PM.

Yesterday's trace of frozen precipitation (sleet) which occurred after 
1:00 PM ties the record for May 1 snowfall.  Previous records were 
made in 1905, 1917, 1921, and 1995.

The 15.0 inches of snowfall for April 2016 was the seventh 
snowiest on record.  April 2016 also saw a new daily record 
of snowfall with 7.3 in. on April 4.  This broke the previous
record of 3.7 in. set in 1975.

BHO Snowiest April, inches (1886-2016):
 
1) 24.2 in 1996
2) 21.5 in 1894
3) 19.0 in 1887
4) 16.2 in 1916
5) 15.4 in 1907
6) 15.1 in 1997
7) 15.0 in 2016
8) 14.0 in 1982
9) 13.5 in 1987
10) 12.2 in 1917

PRELIMINARY STATS FOR APRIL 2016 

TEMPERATURE, Deg. F
Avg. Max. 55.4 [-0.3]
Avg. Min. 36.3 [-1.4]
Mean      45.9 [-0.8]
24-hour corrected mean: 45.5
Max. for month: 80 on 22nd
Min. for month: 19 on 5th

HEATING DEGREE DAYS
Total heating units: 573 [+22]  
Total for the season: 4992 [-1043]
Total for last season: 6271

PRECIPITATION, Inches
Total: 4.36 [-0.19]
Greatest in 24 hrs: N/A
 
SNOWFALL, Inches
Total: 15.0 [+12.0]
Greatest in 24 hrs: N/A

WIND, mph
Avg. uncorrected wind speed: 11.9
Avg. corrected wind speed: 12.4
Prevailing wind direction: S at 17%
Peak gust and direction: 53 SSE on the 7th, 53 S on the 12th

SUNSHINE:
Campbell-Stokes card minutes: 13902 mins. of possible 23250 or 60%
Astronomical total minutes:   14436 mins. of possible 24145 or 60%

Today's Observations:

7 A.M.
Weather: Light drizzle, thick fog
Temperature: 45F; Dew Point: 45F; Wind: NE at 9G16 kts,
Sea-level pressure: 30.05 ins. Hg, rising, then falling
Visibility: 1/8 mile, thick fog 
6-hr Max temp: 45F 
6-hr Min temp: 41F
24-hr precip: 0.10 in.
BHO SA 1155 W3 X 1/8L-F 176/45/45/0509G16/005/ 
8//// 58001 ASOS 60001 70008 MANUAL 70010 10045 20041

10 A.M.
Weather: Light drizzle, thick fog
Temperature: 46F; Dew Point: 46F; Wind: NNE at 7 kts,
Sea-level pressure: 30.02 ins. Hg, falling, then more quickly
Visibility: 1/8 mile, thick fog 
3-hr precip: Trace
BHO SA 1455 W3 X 1/8L-F 167/46/46/0207/002/ 
8//// 58009 MANUAL 6000/

1 P.M.
Weather: Light drizzle, thick fog
Temperature: 48F; Dew Point: 48F; Wind: E at 8 kts,
Sea-level Pressure: 29.93 ins. HG, falling, then more quickly
Visibility: 1 1/2 miles   
6-hr Max temp: 48F 
6-hr Min temp: 45F  
6-hr Precip: 0.29 in.
BHO SA 1755 W4 X 1 1/2L-F 134/48/48/0808/993/ 
8//// 58033 ASOS 60029 MANUAL 60029 10048 20045
 
SUMMARY FOR SUNDAY, MAY 1, 2016 
  
TEMPERATURE (DEGREES F)
MAX.....52   NORMAL.....62
MIN.....39   NORMAL.....43 
MEAN....46   NORMAL.....53

DEPARTURE FROM 30-YEAR NORMAL.........................-7
TOTAL DEPARTURE FOR THE MONTH.........................-7 [-7.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............19   DEPARTURE..........+6
TOTAL HEATING UNITS FOR THE MONTH..............19   DEPARTURE..........+6
TOTAL HEATING UNITS FOR THE SEASON...........5011   DEPARTURE.......-1036
TOTAL HEATING UNITS LAST SEASON TO DATE......6291   DIFFERENCE......-1280   

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................21  S  AT 11:44 A.M.   
                   ASOS........................19 SSE AT  3:53 P.M. 
                   DAVIS.......................19 SE  AT  3:55 P.M.  RMY 20
FASTEST MILE FOR YESTERDAY.....................14 SE  AT  3:53 P.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE..................14 SSE AT  3:56 P.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE.................14 SE  AT  3:54 P.M. 
AVERAGE WIND SPEED AND DIRECTION...............7.9 SSE 
                   ASOS........................8.7
                   DAVIS.......................7.3 S [170 Deg.]
* last of several occurrences 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.10  DEPARTURE......-0.02
                         ASOS..............0.08
TOTAL PRECIPITATION FOR THE MONTH..........0.10  DEPARTURE......-0.02  
                         ASOS..............0.08
TOTAL PRECIPITATION FOR THE YEAR..........17.04  DEPARTURE......-1.63
                         ASOS.............17.45

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)  
TOTAL SNOWFALL 24 HRS ENDING 7 A.M........Trace  DEPARTURE........0.0
TOTAL SNOWFALL FOR THE MONTH..............Trace  DEPARTURE........0.0
TOTAL SNOWFALL FOR THE SEASON..............57.5  DEPARTURE.......-5.7

PRELIMINARY CLIMATE SUMMARY FOR APRIL CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

4/1  66/54/60/+19/0.06/0.0/092/12          39 SSW AERO N/A    RMY 43
4/2  54/40/47/+6/0.47/0.0/023/03           23 SSW AERO N/A    RMY N/A        
4/3  40/23/32/-10/0.85/7.7/354/46          46 W   AERO N/A    RMY 55
4/4  28/21/25/-17/0.63/7.3/000/00          29 NNE AERO N/A    RMY 25
4/5  35/19/27/-16/0.00/0.0/660/85          25 NW  AERO N/A    RMY 27
4/6  41/21/31/-12/T/0.0/483/62             44 S   AERO N/A    RMY N/A   
4/7  56/41/49/+6/1.41/0.0/000/00           53 SSE AERO 59 SSE RMY 55
4/8  52/32/42/-2/T/0.0/353/45              41 WSW AERO 45 WSW RMY 42
4/9  47/29/38/-6/0.00/0.0/417/53           33 NW  AERO 39 NW  RMY 32
4/10 49/26/38/-7/0.00/0.0/735/93           30 NW  AERO 32 NW  RMY 31
4/11 58/40/49/+4/0.01/T/182/23             47 S   AERO 52 S   RMY N/A
4/12 59/37/48/+3/0.30/0.0/040/05           53 S   AERO 60 S   RMY 54 
4/13 53/33/43/-3/0.00/0.0/798/100          21 NNW AERO 25 NNW RMY 21
4/14 48/33/41/-5/0.00/0.0/793/99           28 ENE AERO 28 NNE RMY 26
4/15 54/35/45/-2/0.00/0.0/804/100          26 NNE AERO 28 NNE RMY N/A
4/16 52/39/46/-1/0.00/0.0/783/97           36 NNE AERO 31 NNE RMY 34
4/17 62/36/49/+2/0.00/0.0/809/100          20 NNE AERO 20 NNE RMY 19
4/18 67/45/56/+8/0.00/0.0/715/88           28 ENE AERO 29 NE  RMY 28
4/19 55/41/48/0/0.05/0.0/440/54            25 NW  AERO 30 NW  RMY N/A
4/20 57/41/49/0/0.00/0.0/801/98            29 NNW AERO 30 NNW RMY 29
4/21 76/38/57/+8/0.00/0.0/795/97           28 W   AERO 29 WSW RMY 28
4/22 80/56/68/+19/0.03/0.0/313/38          36 S   AERO 37 S   RMY 36
4/23 60/46/53/+3/0.19/0.0/289/35           26 NNW AERO 60 NNW RMY 24
4/24 59/38/49/-1/0.00/0.0/770/93           23 NW  AERO 25 NW  RMY 24
4/25 63/41/52/+2/0.00/0.0/158/19           23 W   AERO 24 W   RMY N/A
4/26 52/35/44/-7/0.36/0.0/000/00           33 E   AERO 35 E   RMY 31
4/27 61/33/47/-4/0.00/0.0/761/91           28 S   AERO 39 S   RMY 29 
4/28 60/37/49/-3/0.00/0.0/670/80           26 S   AERO 30 S   RMY 27
4/29 56/40/48/-4/0.00/0.0/563/67           20 ESE AERO 22 SE  RMY 20
4/30 62/38/50/-2/0.00/0/0/835/99          24 S   AERO 24 S   RMY 25 

5/1 52/39/46/-7/.../T/.../..               21 S   AERO 22 SE  RMY 20

5/2  low temp since midnight is 41F; normal low now 44F
     
DAILY RECORDS FOR APRIL 2016

4/1/16: NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 54F,
BREAKS PREVIOUS RECORD OF 51F SET IN 1948

4/4/16: NEW DAILY RECORD SNOWFALL OF 7.3 INS, 
BREAKS PREVIOUS RECORD OF 3.7 INS SET IN 1975

4/4/16: NEW DAILY RECORD LOW MAXIMUM TEMPERATURE OF 28F,
BREAKS PREVIOUS RECORD OF 32F SET AND TIED IN 1896, 1908, 1975

4/22/16: NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 56F, 
BREAKS PREVIOUS RECORD OF 55F IN 1977 AND 1992

DAILY RECORDS FOR MAY 2016

5/1/16: DAILY RECORD SNOWFALL OF A TRACE,
TIES PREVIOUS RECORDS SET IN 1905, 1917, 1921, and 1995

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

RECORDS FOR MAY 2
HIGH 92F IN 2001
LOW 29F IN 1903
PRECIP 1.36 INCHES IN 2006
SNOWFALL 1.0 INS IN 1888
PEAK GUST 58 MPH S IN 1983

RECORDS FOR MAY 3
HIGH 92F IN 2001
LOW 31F IN 1888
PRECIP 2.25 INS IN 1900
SNOWFALL TRACE IN 1908, 1985
PEAK GUST 71 MPH W IN 2002

TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle