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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, APRIL 27, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

CLOUDS INCREASE AND RAIN MOVES IN AS PRESSURE DROPS...

The morning began with a partly cloudy sky but as 
pressure decreased, the clouds increased we had 
overcast skies by 10:00 A.M. Light rain began around 
11:30 EST and continued through the 1:00 P.M. 
observation. So far today we measured 0.04 ins. of 
precipitation. The wind remained light and variable
today finally settling from the SE in the afternoon.
Temperatures returned to more seasonable with a max
of 60F by 1:00 P.M. This is the also the daily normal.
Temperatures fell once the rain began and we observed
a temperature of 55F at 1:00 P.M.

Today's Observations:

7 A.M.
Weather: Scattered altocumulus, Scattered cirrocumulus,
thin smoke layer along the horizon SSE-NNE
Temperature: 50F; Dew Point: 41F; Wind: W at 4 kts,
Wind: Light  
Sea-level pressure: 29.92 ins. Hg, rising, then more slowly    
Visibility: 80 miles
6-hr Max temp: 50F
6-hr Min temp: 46F
24-hr precip: Trace 
24-hr snowfall: 0.0 ins.  
Snow depth: 0 ins. 
BHO SA 1155 160 SCT 250 SCT 80 133/50/41/2804/992/ THN 
K LYR ALNG HRZN SSE-NNE WND LGT/ 8/069 51013 10050 20046  

10 A.M.
Weather: Broken altocumulus, overcast cirrostratus,
small brush fire to the SSW plume drifting East
Temperature: 59F; Dew Point: 40F; Wind: SE at 5 kts,
Wind: Light
Sea-level pressure: 29.92 ins. Hg, rising then falling
Visibility: 80 miles
3-hr precip: 0.00 ins.  
3-hr snowfall: 0.0 ins. 
BHO SA 1455 E150 BKN E250 OVC 80 131/59/40/1405/992/ 
SML BRUSH FIRE ESTMTD 5 MI SSW K PLUME DRFTNG E WND 
LGT/ 8/036 55002 

1 P.M.
Weather: Light rain, scattered stratus, overcast altostratus 
Temperature: 55F; Dew Point: 49F; Wind: SSE at 6 kts,
Wind: Light
Sea-level pressure: 29.88 ins. Hg, falling, then more rapidly  
Visibility: 20 miles, distant fog in all directions 
6-hr Max temp: 60F
6-hr Min temp: 50F
6-hr precip: 0.04 ins
6-hr snowfall: 0.00 ins.   
Snow depth: 0 ins.
BHO SA 1755 60 SCT E85 BKN 20R- 117/55/49/1606/988/ 
DSNT FG ALQDS WND LGT/ 8/620 58014 MANUAL 6004/ ASOS 
60004 10060 20050   
    
SUMMARY FOR THURSDAY, APRIL 26, 2018

TEMPERATURE (DEGREES F)
MAX.....66   NORMAL.....60
MIN.....48   NORMAL.....42
MEAN....57   NORMAL.....51

DEPARTURE FROM 30-YEAR NORMAL...........................+6
TOTAL DEPARTURE FOR THE MONTH..........................-83 [-3.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............8   DEPARTURE..........-6
TOTAL HEATING UNITS FOR THE MONTH............578   DEPARTURE.........+81
TOTAL HEATING UNITS FOR THE SEASON..........5636   DEPARTURE........-345
TOTAL HEATING UNITS LAST SEASON TO DATE.....5313   DIFFERENCE.......+323

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................36 WNW AT  5:09 P.M.* 
                   AERO........................35 WNW AT  4:17 P.M. 
                   ASOS........................38 W   AT  4:21 P.M.
                   DAVIS.......................38 M   AT  4:19 P.M.** RMY 37
FASTEST MILE FOR YESTERDAY.....................28 SE  AT  5:11 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................28 SE  AT  5:11 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................27 M   AT 12:39 P.M.**
AVERAGE WIND SPEED AND DIRECTION.............13.9 W
                   ASOS......................13.9
                   DAVIS.....................12.8 M **
*  Last of multiple occurrences
** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.14
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........5.54  DEPARTURE......+1.51
                         ASOS..............5.73  
TOTAL PRECIPITATION FOR THE YEAR..........24.34  DEPARTURE......+6.49
                         ASOS.............25.97

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.........0.0
TOTAL SNOWFALL FOR THE MONTH................2.6  DEPARTURE........-0.3
TOTAL SNOWFALL FOR THE SEASON..............92.8  DEPARTURE.......+30.1

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
*   : Estimated data 

4/01 58/33/46/+5/0.00/0.0/336/44   45 SSW AERO 43 SSW RMY N/A  
4/02 38/30/34/-7/0.13/1.6/077/10   20 SSW AERO 15 SSW RMY 17
4/03 48/30/39/-3/..../0.0/238/31   28 SSE AERO 25 SSE RMY 25
4/04 54/36/45/+3/..../0.0/000/00   56 WNW AERO 56 WNW RMY 54
4/05 40/27/34/-9/0.00/0.0/760/98   53 WNW AERO 53 WNW RMY 52 
4/06 41/25/33/-10/0.25/1.0/156/20  37 S   AERO 36 S   RMY 38
4/07 46/32/35/-4/0.00/0.0/312/40   32 WNW AERO 35 WNW RMY 34
4/08 41/29/35/-9/0.00/0.0/290/37   35 WNW*AERO 31 WNW RMY 34
4/09 45/24/35/-9/0.00/0.0/715/01   28 WNW*AERO 25 WNW RMY 29
4/10 39/31/35/-10/T/T/000/00       14 SSW AERO 13 SSW RMY N/A
4/11 48/29/39/-6/T/0.0/364/46      24 SSE AERO 23 SSE RMY 25 
4/12 61/33/47/+2/0.03/0.0/.../..   39 SSW AERO 38 SSW RMY 41 
4/13 65/47/56/+10/T/0.0/.../..     37 SSW AERO 37 SSW RMY N/A
4/14 51/36/44/-2/0.00/0.0/.../..   33 ENE AERO 31 ENE RMY N/A
4/15 36/30/33/-14/..../T/.../..    39 ENE AERO 39 ENE RMY N/A
4/16 55/32/44/-3/..../.../..       41 ENE AERO 43 ENE RMY 41
4/17 48/36/42/-5/0.00/0.0/.../..   37 W   AERO 33 W   RMY 37
4/18 53/32/43/-5/..../0.0/.../..   35 W   AERO 31 W   RMY 34
4/19 41/34/38/-10/0.22/T/.../..    28 WNW AERO 25 WNW RMY N/A 
4/20 52/31/42/-7/0.00/0.0/.../..   34 NW  AERO 33 NW  RMY 36
4/21 60/33/47/-2/0.00/0.0/.../..   28 NW  AERO 26 NW  RMY 29
4/22 61/36/49/0/0.00/0.0/.../..    25 NW  AERO 24 NW  RMY 26 
4/23 62/40/51/+1/0.00/0.0/.../..   25 S   AERO 25 S   RMY 26
4/24 67/39/53/+3/0.00/0.0/.../..   31 S   AERO 29 S   RMY 32
4/25 57/47/52/+2/..../0.0/.../..   32 SE  AERO 32 SE  RMY 33 
4/26 66/48/57/+6/..../0.0/.../..   36 WNW AERO 35 WNW RMY 37 

4/27 Low temp since midnight is 46F; normal low is now 42F

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

RECORDS FOR APRIL 27
HIGH 93 IN 1990
LOW 28 IN 1919
PRECIP 1.89 IN 1979
SNOWFALL 2.7 IN. IN 1993
PEAK GUST 65e MPH N IN 1941

RECORDS FOR APRIL 28
HIGH 92 IN 1990, 2009
LOW 26 IN 1947
PRECIP 2.41 IN 1904
SNOWFALL 10.0 IN. IN 1987
PEAK GUST 69 MPH NE 1967

TODAY'S REPORT PREPARED BY: K.Geagan