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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, APRIL 20, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME

0.11 INCHES OF PRECIPITATION MEASURED OVERNIGHT

Last night, 0.11 inches of precip fell from around 4:30 P.M. to 1:00 A.M. 
Despite the dry spell we have been having, we are still 1.32 inches above 
normal for precip. this month. It has been cloudy all day today with mostly 
broken and overcast layers of stratus and some stratocumulus later in the 
morning. Distant fog has been lingering in the area, bringing down the 
visibility. The clouds began to break up and the fog began to lift in the 
afternoon slightly, but the light wind began increasing. Winds shifted from 
SW in the morning to NE by the 1:00 P.M. EST observation. Temperatures warmed 
to a max of 58F by 1:00 P.M., and dew points have remained in the low 40s.


Today's Observations:

7 A.M.
Weather: Overcast stratus
Temperature: 46F; Dew Point: 45F; Wind: SW at 4 kts,
Wind Speed: Light
Sea-level pressure: 30.15 ins. Hg, falling unsteadily
Visibility: 10 miles, distant fog in all directions
6-hr Max temp: 46F
6-hr Min temp: 42F
24-hr precip: 0.11 in.
24-hr snowfall: 0.0 in.
BHO SA 1155 E8 OVC 10 209/46/45/2204/015/ DSNT FG ALQDS WND LGT/
8/6// 57002 MANUAL 70011 ASOS 70011 10046 20042

10 A.M.
Weather: Broken stratocumulus, broken stratus
Temperature: 54F; Dew Point: 46F; Wind: ENE at 5 kts,
Wind Speed: Light
Sea-level pressure: 30.14 ins. Hg, steady then falling
Visibility: 20 miles, distant fog in all directions
BHO SA 1455 E12 BKN 42 BKN 20 205/54/46/0705/014/ DSNT FG ALQDS 
WND LGT/ 8/600 58004

1 P.M.
Weather: Few cumulus in all directions, broken stratocumulus, broken stratus, 
small fire 1 mile NW with thin smoke plume drifting SW
Temperature: 56F; Dew Point: 46F; Wind: NE at 9G16 kts
Sea-level pressure: 30.11 ins. Hg, falling, then more quickly
Visibility: 50 miles, except 40 miles SW-N and 20 miles NNE-NE
6-hr Max temp: 58F
6-hr Min temp: 46F
BHO SA 1755 E19 BKN 41 BKN 50 197/56/46/0409G16/011/ FEW CU ALQDS 
DSNT FG ALQDS VSBY SW-N 40 AND NNE-NE 20 SML FIRE 1 MI NW THN K PLUME 
DRFTNG SW/ 8/600 55008 10058 20046


SUMMARY FOR WEDNESDAY, APRIL 19, 2017
 
TEMPERATURE (DEGREES F)
MAX.....54   NORMAL.....57
MIN.....34   NORMAL.....39
MEAN....44   NORMAL.....48

DEPARTURE FROM 30-YEAR NORMAL.........................-4
TOTAL DEPARTURE FOR THE MONTH........................+98 [+5.0 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............21   DEPARTURE..........+4
TOTAL HEATING UNITS FOR THE MONTH.............299   DEPARTURE.........-90
TOTAL HEATING UNITS FOR THE SEASON...........5201   DEPARTURE........-671
TOTAL HEATING UNITS LAST SEASON TO DATE......4840   DIFFERENCE.......+361

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................31 S  AT 5:54 P.M.
                   AERO........................33 S  AT 5:06 P.M.
                   ASOS........................34 S  AT 3:34 P.M.
                   DAVIS.......................36 SW AT 4:03 P.M. RMY 34
FASTEST MILE FOR YESTERDAY.....................25 S  AT 5:03 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................25 S  AT 5:05 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................22 S  AT 5:06 P.M.
AVERAGE WIND SPEED AND DIRECTION.............13.2 S
                   ASOS......................13.8
                   DAVIS.....................10.7 SSW [200 deg.]
* LAST OF MULTIPLE OCCURRENCES

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.11  DEPARTURE......-0.02
                         ASOS..............0.11
TOTAL PRECIPITATION FOR THE MONTH..........4.39  DEPARTURE......+1.32
                         ASOS..............4.40
TOTAL PRECIPITATION FOR THE YEAR..........18.51  DEPARTURE......+1.44
                         ASOS...............N/A ***
*** ASOS annual total not available due to erroneous readings

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.......-0.1
TOTAL SNOWFALL FOR THE MONTH................2.7  DEPARTURE.......+0.2
TOTAL SNOWFALL FOR THE SEASON..............66.4  DEPARTURE.......+4.2


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

4/1  35/31/33/-8/2.21/2.7/000/00           40 ENE AERO 41 ENE RMY 41
4/2  53/30/42/+1/0.00/0.0/552/72           32 NW  AERO 33 NW  RMY 34
4/3  60/35/48/+6/0.00/0.0/685/89           21 W*  AERO 20 NW  RMY N/A
4/4  42/35/39/-3/0.78/0.0/000/00           41 ESE AERO 43 ESE RMY 42
4/5  41/35/38/-5/0.00/0.0/000/00           21 NNW AERO 20 NNW RMY N/A
4/6  55/35/45/+2/1.27/0.0/000/00           35 SSE AERO 37 S   RMY 37  TSTM
4/7  53/38/46/+3/0.00/0.0/226/29           43 SSW AERO 47 SSW RMY 48
4/8  50/34/42/-2/0.00/0.0/666/85           37 WNW AERO 40 WNW RMY 39
4/9  65/34/50/+6/0.00/0.0/716/91           23 W   AERO 23 W   RMY N/A
4/10 77/45/61/+16/0.00/0.0/560/71          37 S   AERO 37 S   RMY 39
4/11 85/50/68/+23/0.00/0.0/642/81          28 S   AERO 28 S   RMY 30
4/12 68/47/58/+13/0.01/0.0/.../..          26 WNW AERO 28 WNW RMY N/A
4/13 58/39/49/+3/0.00/0.0/.../..           28 WNW AERO 31 NW  RMY 30 
4/14 62/40/51/+5/0.00/0.0/.../..           22 NNW AERO 22 NNW RMY 24
4/15 68/40/54/+7/0.01/0.0/.../..           40 SSW AERO 45 SSW RMY 45
4/16 86/55/71/+24/T/0.0/.../..             38 W*  AERO 39 SW  RMY 42
4/17 75/48/62/+15/0.00/0.0/.../..          37 W   AERO 37 W   RMY 43
4/18 52/35/44/-4/0.00/0.0/.../..           25 ENE AERO 23 ENE RMY 25
4/19 54/34/44/-4/..../0.0/.../..           31 S   AERO 33 S   RMY 34

4/20 Low temp since midnight is 41F; normal low is now 40F


DAILY RECORDS FOR APRIL 2017

4/11/17: DAILY RECORD MAXIMUM TEMPERATURE OF 85F,
         BREAKS PREVIOUS RECORD OF 78F SET IN 1945

4/11/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 50F,
         TIES WITH PREVIOUS RECORD SET IN 1955


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

RECORDS FOR APRIL 20
HIGH 88 IN 1927
LOW 18 IN 1897
PRECIP 1.14 IN 1972
SNOWFALL 2.5 IN. IN 1904, 1972
PEAK GUST 76 MPH WNW IN 1963

RECORDS FOR APRIL 21
HIGH 85 IN 1923
LOW 22 IN 1908
PRECIP 3.18 IN. IN 1991 
SNOWFALL 0.8 IN. IN 1947
PEAK GUST 76e MPH NE IN 1940

TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle and Lizzy Suzedell