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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, APRIL 24, 2020
ALL TIMES ARE IN EASTERN STANDARD TIME

AN UNSEASONABLY CHILLY DAY WITH RAIN AND FOG
FOLLOWING YESTERDAY'S BRILLIANT SUNSHINE...

After a bright and tranquil Thursday, today has
seen a return to overcast skies, fog and light rain.
Visibility has maxed out so far at 15 miles 
slipping to just a 1/2 mile by 1 PM. Overnight
precipitation totaled 0.15 ins with an additional
0.08 ins through the morning and into this afternoon.
Winds have been somewhat light with most gusts in 
the 20 MPH range.

Some interesting notes in the temperature department:
April has been below average - currently sitting at
-2.2 degrees for the month to date. Consequently, this
is the first month of 2020 to feature a below average
month. Also of interest is that the high so far today is
41F, which is the average low for this date! This (so
far) ties for the 4th lowest high temperature on
record for April 24th. We will see if we can add a few 
degrees before the stroke of midnight. Nonetheless, 
very unseasonably chilly today. 

Our high temperature so far today is 41F, which is 18 
degrees below our daily normal high temperature of 59F. 
The low since midnight is 37F, which is 4 degrees below 
the daily normal low of 41F. 


Today's Observations:

7 A.M.
Weather: Overcast Stratus, light rain
Temperature: 38F; Dew Point: 38F; Relative Humidity: 100%
Wind: NE at 10 kts
Sea-level pressure: 29.83 ins. Hg: falling, then more rapidly
Visibility: 15 miles, fog
6-hr Max temp: 38F
6-hr Min temp: 37F
24-hr Precip:  0.15 ins.
24-hr Snowfall: 0.0 ins.
BHO SA 1155 E12 OVC 15R-F 102/38/38/0410/983/ R-CTD/ 8/6//
70015 5821 10038 20037

10 A.M.
Weather: Overcast Stratus, light drizzle
Temperature: 40F; Dew Point: 40F; Relative Humidity: 100%
Wind: NE at 10G17 kts
Sea-level pressure: 29.77ins. Hg: falling, then more slowly
Visibility: 5 miles, fog 
3-hr Precip:   0.02 ins.
3-hr Snowfall: 0.0 ins.
BHO SA 1455 E10 OVC 5L-F 082/40/40/0410G17/977/ L-CTD/ 8/6//
6002 53020

1 P.M.
Weather: Vertical visibility 300 ft, sky obscured, light rain
Temperature: 39F; Dew Point: 39F; Relative Humidity: 100%
Wind: NNE at 11G27 kts
Peak Wind: 31 MPH (27 kts) NNE @ 12:45 P.M.
Sea-level pressure: 29.74 ins. Hg: falling, then more slowly
Visibility: 1/2 mile, fog
6-hr Max temp: 41F
6-hr Min temp: 37F
6-hr Precip:  0.08 ins.
6-hr Snowfall: 0.0 ins.
BHO SA 1755 X W3 1/2R-F 071/39/39/0211G27/974/
R-CTD PK WND 0327/45/ 8/// 6008 56011 10041 20038


SUMMARY FOR THURSDAY, APRIL 23, 2020 

TEMPERATURE (DEGREES F)
MAX.....55   NORMAL.....59
MIN.....29   NORMAL.....41
MEAN....42   NORMAL.....50

DEPARTURE FROM 30-YEAR NORMAL....................-8
TOTAL DEPARTURE FOR THE MONTH...................-47 [-2.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............23  DEPARTURE........+8
TOTAL HEATING UNITS FOR THE MONTH..............498  DEPARTURE.......+45
TOTAL HEATING UNITS FOR THE SEASON............5371  DEPARTURE......-565
TOTAL HEATING UNITS LAST SEASON TO DATE.......5781  DEPARTURE......-410

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................31 W   AT  12:47 A.M.  
                   AERO.........................29 W   AT   1:19 A.M  
                   ASOS.........................30 W   AT  12:02 A.M. 
                   DAVIS........................32 NWN AT  12:02 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY......................26 W   AT  12:02 A.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE...................23 W   AT  12:14 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................25 W   AT  12:03 A.M.
AVERAGE WIND SPEED AND DIRECTION................12.0 W               
                   ASOS.........................12.1
                   DAVIS........................12.3 WSW [255 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.15  DEPARTURE......+0.02
                         ASOS..............0.14
TOTAL PRECIPITATION FOR THE MONTH..........6.15  DEPARTURE......+2.53
                         ASOS..............6.33
TOTAL PRECIPITATION FOR THE YEAR..........15.48  DEPARTURE......-2.14
                         ASOS.............16.06

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.......-0.1
TOTAL SNOWFALL FOR THE MONTH................4.3  DEPARTURE.......+1.5
TOTAL SNOWFALL FOR THE SEASON..............31.9  DEPARTURE......-30.6

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/.../..         41 W   AERO 40 W   RMY N/A
04/15  52/36/44/-3/0.02/0.0/.../..         37 W   AERO 36 W   RMY 37
04/16  47/32/40/-7/T/T/.../..              33 WNW AERO 33 WNW RMY 32
04/17  49/29/39/-8/..../0.0/.../..         41 W   AERO 39 W   RMY 41
04/18  37/31/34/-14/..../4.3/.../..        29 NE  AERO 25 NE  RMY 25
04/19  60/31/46/-2/0.00/0.0/.../..         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 The low since midnight is 37F, daily normal minimum is 41F 

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

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

RECORDS FOR APRIL 24
HIGH 82 IN 2001
LOW 22 IN 1930
PRECIP 2.51 INS IN 1898
SNOWFALL 1.2 INS IN 1967
PEAK GUST 59 MPH NW IN 1962

RECORDS FOR APRIL 25
HIGH 83 IN 2009
LOW 24 IN 1892
PRECIP 1.38 IN. IN 1901
SNOWFALL 0.7 IN. IN 2002.
PEAK GUST 66 MPH SE IN 1968

TODAY'S REPORT PREPARED BY: Andrew Swanson