Sunday, May 1, 2016

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, MAY 1, 2016
ALL TIMES ARE IN EASTERN STANDARD TIME

OVERCAST WITH VERY LIGHT RAIN LATE MORNING
AND LIGHT RAIN MIXED WITH SLEET OR ICE PELLETS JUST
AFTER 2 P.M. EDT

The air is extremely dry today and so most of the rain
headed our way has been drying through early afternoon.
Just after 2 P.M. ice pellets were falling mixed with
rain, a temperature of 51F, a dew point of 22F and a
relative humidity around 32%

April was 0.8 degree colder than normal and may have been
the coldest April since 2007.

ALL OF THE APRIL DATA WILL BECOME AVAILABLE EARLY THIS WEEK.

Today’s Observations:

7 A.M.
Weather: Overcast altocumulus and altostratus
Temperature: 45F; Dew Point: 33F; Wind: S at 7 kts,
Sea-level pressure: 30.26 ins. Hg, rising, then more slowly
Visibility: 60 miles
6-hr Max temp: 44F
6-hr Min temp: 41F
24-hr precip: 0.00 in.
BHO SA 1155 E120 OVC 60 247/44/33/1807/026/ BRGHT SPTS IOVC N-NE
AND BRGHT ALG HRZN DSNT NE-ESE VSBY NW 70/ 8/07/ 51009
10044 20041

10 A.M.
Weather: Overcast nimbostratus, light rain, very light
Temperature: 52F; Dew Point: 27F; Wind: SSE at 9 kts,
Wind: Direction variable ESE-SSW
Sea-level pressure: 30.25 ins. Hg, falling slightly
Visibility: 40 miles, N-SE, 50 miles, SW-NW 30 miles, light rain
3-hr precip: trace
BHO SA 1455 E65 OVC 40R- 243/52/27/1609/025/ VSBY N-SE 50
VSBY SW-NW 30 LWRG R-BXX PCPN VRY LGT WND 12V20/ 8/02/ 58004
MANUAL 6000/

1 P.M.
Weather: Overcast nimbostratus, light rain, very light
Temperature: 51F; Dew Point: 22F; Wind: SSE at 10 kts,
Sea-level Pressure: 30.24 ins. HG, falling slightly
Visibility: 35 miles
6-hr Max temp: 52F
6-hr Min temp: 44F
6-hr Precip:   trace
BHO SA 1755 E/// OVC 35R- 240/51/22/1610/024/ PCPN VRY LGT/
8//// 58003 6000/ 10052 20044

SUMMARY FOR SATURDAY APRIL 30, 2016

TEMPERATURE (DEGREES F)
MAX…..62   NORMAL…..61
MIN…..38   NORMAL…..42
MEAN….50   NORMAL…..52

DEPARTURE FROM 30-YEAR NORMAL…………………….-2
TOTAL DEPARTURE FOR THE MONTH……………………-21 [-0.8] DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..15   DEPARTURE……….+2
TOTAL HEATING UNITS FOR THE MONTH………….573   DEPARTURE………+22
TOTAL HEATING UNITS FOR THE SEASON………..4992   DEPARTURE…….-1043
TOTAL HEATING UNITS LAST SEASON TO DATE……6271   DIFFERENCE……-1279

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….24  S  AT 7:07 P.M. *
ASOS……………………24  S  AT 7:08 P.M.
DAVIS…………………..23  S  AT 6:54 P.M.  RMY 25
FASTEST MILE FOR YESTERDAY…………………21  S  AT 6:56 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………20  S  AT 6:57 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..19  S  AT 6:57 P.M.
AVERAGE WIND SPEED AND DIRECTION……………9.5 S
ASOS……………………9.6
DAVIS…………………..8.7 SSE[160 Deg.] * last of several occurrences

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.00 DEPARTURE…….-0.13
ASOS…………..0.00
TOTAL PRECIPITATION FOR THE MONTH……….4.36  DEPARTURE……-0.19
ASOS…………..4.36
TOTAL PRECIPITATION FOR THE YEAR……….16.94  DEPARTURE……-1.60
ASOS………….17.37

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE…….-0.0
TOTAL SNOWFALL FOR THE MONTH……………15.0  DEPARTURE……+12.0
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  low temp> since midnight is 41F; normal low now 43f
trace of ice pellets at 1305E!

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

RECORDS FOR MAY 1
HIGH 87F IN 1899
LOW 29F IN 1978
PRECIP 2.53 INCHES IN 1921
SNOWFALL TRACE IN 1905,1917,1921,1995.2016
PEAK GUST 57 MPH NW IN 1974

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

TODAY’S REPORT PREPARED BY: Robert Skilling