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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, MAY 5, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

COOLER, BUT NICE WEATHER TODAY WITH DRY AIR AND EXCELLENT
VISIBILITY....

After 3 days in a row of temperatures getting to 70 degrees
or better, today has reverted back to cooler times with 
temperatures that are coming up a bit below normal for the 
day. Despite the cooler temperatures, there has been an 
abundance of sunshine with only scattered clouds around. 
This combined with another day of excellent visibility of
around 70 miles this afternoon, we're experiencing a
splendid day!

The high so far today is 58F, this is 5 degrees below our
daily normal high temperature of 63F. The low since 
midnight is 40F, which is 5 degrees below the daily normal
low of 45F. 


Today's Observations:

7 A.M.
Weather: Scattered altocumulus, few stratocumulus distant S-W-NW
Temperature: 45F; Dew Point: 25F; Relative Humidity: 45%
Wind: WNW at 18G26 kts, peak wind WNW 26 kts at 6:48am  
Sea-level pressure: 29.79 ins. Hg: rising, then steady
Visibility: 60 miles
6-hr Max temp: 44F
6-hr Min temp: 40F
24-hr Precip:   TRACE
24-hr Snowfall: 0.0 ins.
BHO SA 1155 100 SCT 60 088/45/25/3018G26/979/ FEW SC DSNT S-W-NW
PK WND 3126/48/ 8/570 51008 70000 10044 20040

10 A.M.
Weather: Scattered stratocumulus, scattered altocumulus
Temperature: 51F; Dew Point: 26F; Relative Humidity: 37%
Wind: WNW at 9G22 kts
Sea-level pressure: 29.81 ins. Hg: rising, then more rapidly
Visibility: 70 miles 
3-hr Precip:  0.00 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 60 SCT 100 SCT 70 095/51/26/2909G22/981/ 8/570 53007

1 P.M.
Weather: Scattered stratocumulus, thin scattered cirrus
Temperature: 57F; Dew Point: 28F; Relative Humidity: 32%
Wind: WNW at 13G26 kts, peak wind WNW 26 kts at 12:42pm
Sea-level pressure: 29.81 ins. Hg: falling, then rising
Visibility: 70 miles 
6-hr Max temp: 58F
6-hr Min temp: 45F
6-hr Precip:  0.00 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 60 SCT 250 -SCT 70 094/57/28/3013G26/981/ CI DSNT SW-W
PK WND 3026/42/ 8/501 55001 10058 20045

SUMMARY FOR MONDAY, MAY 4, 2020 

TEMPERATURE (DEGREES F)
MAX.....72   NORMAL.....63
MIN.....45   NORMAL.....44
MEAN....59   NORMAL.....54

DEPARTURE FROM 30-YEAR NORMAL.................. +5
TOTAL DEPARTURE FOR THE MONTH..................+27 [+6.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY................6  DEPARTURE....... -6
TOTAL HEATING UNITS FOR THE MONTH...............22  DEPARTURE.......-27
TOTAL HEATING UNITS FOR THE SEASON............5543  DEPARTURE......-540
TOTAL HEATING UNITS LAST SEASON TO DATE.......5966  DEPARTURE......-423

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL HEATING UNITS FOR YESTERDAY................0  DEPARTURE........ 0
TOTAL HEATING UNITS FOR THE MONTH................2  DEPARTURE........+1
TOTAL HEATING UNITS FOR THE SEASON...............2  DEPARTURE........-1
TOTAL HEATING UNITS LAST SEASON TO DATE..........0  DEPARTURE........+2

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................37 NW  AT  9:09 P.M.  
                   AERO.........................40 WNW AT  2:12 P.M.  
                   ASOS.........................38 NW  AT  9:01 P.M. 
                   DAVIS........................38 NW  AT  9:01 P.M. RMY 39
FASTEST MILE FOR YESTERDAY......................26 NW  AT  9:15 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................25 NW  AT  5:50 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................27 NW  AT  5:49 P.M.
AVERAGE WIND SPEED AND DIRECTION................14.1 WNW               
                   ASOS.........................13.5
                   DAVIS........................14.2 WNW [301 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...TRACE  DEPARTURE......-0.13
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........0.94  DEPARTURE......+0.45
                         ASOS..............0.96
TOTAL PRECIPITATION FOR THE YEAR..........17.97  DEPARTURE......-1.07
                         ASOS.............18.60

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........0.0
TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE........0.0
TOTAL SNOWFALL FOR THE SEASON..............31.9  DEPARTURE......-30.8

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

04/01  42/28/35/-6/0.00/0.0/008/01         28 NE  AERO 28 NE  RMY 30
04/02  46/35/41/0/.../0.0/000/00           39 NW  AER0 40 NW  RMY 41
04/03  42/38/40/-2/..../0.0/000/00         48 NE  AERO 53 NE  RMY 49
04/04  46/36/41/-1/..../0.0/278/36         38 NE  AERO 38 NE  RMY N/A
04/05  55/36/46/+3/T/0.0/039/05            22 S   AERO 21 S   RMY 21
04/06  61/40/51/+8/0.00/0.0/732/94         29 NW  AERO 30 NW  RMY 29
04/07  63/42/53/+10/0.00/0.0/649/83        29 W   AERO 30 W   RMY 28
04/08  50/41/46/+2/..../.../047/06         23 S   AERO 22 S   RMY 22 
04/09  47/37/42/-2/..../.../000/00         58 W   AERO 58 W   RMY 56
04/10  47/35/41/-4/0.02/T/324/41           48 W   AERO 50 W   RMY 53 
04/11  51/33/42/-3/0.00/0.0/730/92         38 WNW AERO 39 WNW RMY 40
04/12  60/33/47/+2/0.00/0.0/326/41         38 S   AERO 40 S   RMY N/A
04/13  59/50/55/+9/1.42/0.0/000/00         79 S   AERO 83 S   RMY 78
04/14  57/41/49/+3/0.00/0.0/641/80         41 W   AERO 40 W   RMY N/A
04/15  52/36/44/-3/0.02/0.0/450/56         37 W   AERO 36 W   RMY 37
04/16  47/32/40/-7/T/T/379/47              33 WNW AERO 33 WNW RMY 32
04/17  49/29/39/-8/..../0.0/591/73         41 W   AERO 39 W   RMY 41
04/18  37/31/34/-14/..../4.3/000/00        29 NE  AERO 25 NE  RMY 25
04/19  60/31/46/-2/0.00/0.0/693/85         40 SSW AERO 40 SSW RMY 41
04/20  49/37/43/-6/0.00/0.0/.../..         25 ENE AERO 22 W   RMY N/A
04/21  53/33/43/-6/..../.../.../..         52 S   AERO 52 S   RMY 52
04/22  43/30/37/-12/0.00/0.0/.../..        51 W   AERO 50 W   RMY 50
04/23  55/29/42/-8/0.00/0.0/.../..         31 W   AERO 29 W   RMY N/A
04/24  42/37/40/-10/..../.../.../..        31 NNE AERO 29 NNE RMY 29
04/25  60/38/49/-1/0.00/0.0/.../..         25 S   AERO 24 S   RMY 24
04/26  51/38/45/-6/..../0.0/.../..         51 NE  AERO 50 NE  RMY 50
04/27  39/35/37/-14/..../T/.../..          54 NE  AERO 52 NNE RMY 55
04/28  48/35/42/-10/..../.../.../..        28 N   AERO 27 N   RMY N/A
04/29  55/35/45/-7/0.00/0.0/.../..         24 ENE AERO 23 ENE RMY 22
04/30  52/42/47/-5/.../0.0/.../..          36 SE  AERO 32 SE  RMY N/A

DAILY RECORDS FOR APRIL 2020

4/13/2020
NEW PEAK GUST OF 79 MPH S, REPLACING THE OLD
RECORD OF 59 MPH SSW IN 1995

4/18/2020
NEW RECORD SNOWFALL OF 4.3 INS, REPLACING THE OLD
RECORD OF 3.7 INS IN 1965

4/27/2020
NEW RECORD LOW MAX TEMPERATURE OF 39F, REPLACING
THE OLD RECORD OF 40F IN 1917

PRELIMINARY CLIMATE SUMMARY FOR MAY 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

05/01  64/52/58/+5/..../0.0/.../..         46 SSE  AERO 44 SSE RMY N/A 
05/02  70/42/56/+3/..../0.0/.../..         41 NW   AERO 40 NW  RMY N/A
05/03  78/55/67/+14/0.00/0.0/.../..        35 SSW  AERO 35 SSW RMY 36
05/04  72/45/59/+5/T/0.0/.../..            37 NW   AERO 40 WNW RMY 39  

05/05 The low since midnight is 40F, the daily normal low is 45F

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

RECORDS FOR MAY 5
HIGH 92F IN 1949
LOW 30F IN 1891
PRECIP 2.74 INCHES IN 1922
SNOWFALL 3.0 INCHES IN 1917
PEAK GUST 58 MPH S IN 1966 & 58e MPH SW IN 1976

RECORDS FOR MAY 6
HIGH 90F IN 1930
LOW 29F IN 1891
PRECIP 1.04 INCHES IN 1890
SNOWFALL TRACE IN 1917,1996
PEAK GUST 65 MPH SSE IN 1989

TODAY'S REPORT PREPARED BY: Matt Douglas