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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 19, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

LIGHTER WINDS WITH RAIN BEGINNING IN THE AFTERNOON

Winds were lighter today out of the east. A peak gust of 22 MPH was measured at 8:56 A.M. EST, and since the morning, winds have decreased. Yesterday, the peak gust was much higher at 35 MPH out of the ENE, occurring at 9:35 A.M. Temperatures have continued to be cool, as the average temperature was yesterday was 53F, which is 5F below normal. A higher daytime maximum of 57F was reached today, but this is still 5F below the normal high temperature of 62F. Around 11:15 A.M., light rain began to fall at Great Blue Hill. 0.01 ins. fell by the 1:00 P.M observation, which now puts us 0.83 ins. below the normal amount of precipitation for the month of May. However, Blue Hill is well above the normal amount of precipitation for the entire year so far, as 6.11 ins. more than normal has fallen.


Today's Observations:

7 A.M.
Weather: Scattered stratus, few altocumulus NW-E, broken cirrus
Temperature: 51F; Dew Point: 39F; Wind: E at 8G16 kts
Sea-level pressure: 30.43 ins. Hg, falling, then rising    
Visibility: 60 miles, except 30 miles E-SW, distant fog E-SW
6-hr Max temp: 50F
6-hr Min temp: 43F
BHO SA 1155 16 SCT E250 BKN 60 305/51/39/0808G16/043/ FEW AC NW-E 
VSBY E-SW 30 DSNT FG E-SW/ 8/532 53005 10050 20043

10 A.M.
Weather: Few cumulus in all directions, scattered stratocumulus, 
broken cirrostratus
Temperature: 56F; Dew Point: 45F; Wind: E at 6 kts
Sea-level pressure: 30.40 ins. Hg, steady, then falling
Visibility: 60 miles, except 30 miles E-S, distant fog in all directions
BHO SA 1455 18 SCT E250 BKN 60 294/56/45/0906/040/ FEW CU ALQDS 
VSBY E-S 30 DSNT FG ALQDS/ 8/507 58001

1 P.M.
Weather: Light rain, overcast stratus
Temperature: 51F; Dew Point: 49F; Wind: E at 6 kts 
Sea-level pressure: 30.34 ins. Hg, falling unsteadily
Visibility: 5 miles, fog
6-hr Max temp: 57F
6-hr Min temp: 51F
6-hr precip:   0.01 ins.
BHO SA 1755 E9 OVC 5R-F 274/51/49/0906/034/ 8/6// MANUAL 
60001 ASOS 60001 57020 10057 20051


SUMMARY FOR FRIDAY, MAY 18, 2018

TEMPERATURE (DEGREES F)
MAX.....62   NORMAL.....67
MIN.....43   NORMAL.....48
MEAN....53   NORMAL.....58

DEPARTURE FROM 30-YEAR NORMAL..........................-5
TOTAL DEPARTURE FOR THE MONTH........................+102 [+5.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............12   DEPARTURE..........+4
TOTAL HEATING UNITS FOR THE MONTH............109   DEPARTURE.........-76
TOTAL HEATING UNITS FOR THE SEASON..........5802   DEPARTURE........-418
TOTAL HEATING UNITS LAST SEASON TO DATE.....5553   DIFFERENCE.......+249

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE..........-1
TOTAL COOLING UNITS FOR THE MONTH..............36   DEPARTURE.........+29
TOTAL COOLING UNITS FOR THE SEASON.............36   DEPARTURE.........+27
TOTAL COOLING UNITS LAST SEASON TO DATE........48   DEPARTURE.........-12

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................35 ENE AT 9:35 A.M.
                   AERO........................33 ENE AT 9:32 A.M. 
                   ASOS........................35 NE  AT 2:17 A.M.
                   DAVIS.......................33 M   AT 1:36 A.M.** RMY N/A
FASTEST MILE FOR YESTERDAY.....................26 ENE AT 9:35 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................25 ENE AT 9:44 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................25 M   AT 9:38 A.M.**
AVERAGE WIND SPEED AND DIRECTION.............13.6 E
                   ASOS......................13.7
                   DAVIS.....................12.8 M**

** 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..........1.37  DEPARTURE......-0.84
                         ASOS..............1.32  
TOTAL PRECIPITATION FOR THE YEAR..........26.68  DEPARTURE......+6.10
                         ASOS.............28.24

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..............92.8  DEPARTURE.......+30.0

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

5/01 65/39/52/-1/0.00/0.0/625/74    25 WNW AERO 21 WNW RMY 25
5/02 88/59/74/+21/0.00/0.0/584/69   37 WSW AERO 29 WSW RMY 35 
5/03 90/67/70/+26/..../0.0/433/51   36 SW  AERO 32 WSW RMY 36  
5/04 84/67/74/+20/..../0.0/102/12   39 SSW AERO 37 SSW RMY N/A
5/05 73/54/64/+10/0.00/0.0/615/72   56 W   AERO 55 W   RMY N/A
5/06 65/48/57/+3/0.21/0.0/000/00    24 NE  AERO 18 NE  RMY 21
5/07 62/49/56/+1/0.00/0.0/713/83    26 ENE AERO 22 NE  RMY 24
5/08 73/46/60/+5/0.00/0.0/852/99    25 SSE AERO 21 ESE RMY 23 
5/09 74/48/61/+6/..../0.0/768/89    23 ESE AERO 18 ESE RMY 21 
5/10 73/48/61/+6/..../0.0/.../..    33 S   AERO 30 S   RMY 32 
5/11 70/51/61/+5/..../0.0/.../..    26 WNW AERO 24 NW  RMY 28
5/12 51/47/49/-7/0.19/0.0/.../..    25 E   AERO 23 E   RMY N/A
5/13 58/46/52/-4/T/0.0/.../..       20 S   AERO 17 S   RMY 16 
5/14 73/47/60/+3/0.00/0.0/.../..    23 S   AERO 18 S   RMY 21
5/15 83/54/69/+12/..../0.0/.../..   51 NW  AERO 50 NW  RMY 54 TSTM
5/16 56/49/53/-4/T/0.0/.../..       32 ENE AERO 28 ENE RMY 30
5/17 72/51/62/+5/0.02/0.0/.../..    17 SW  AERO 14 SW  RMY N/A
5/18 62/43/53/-5/0.00/0.0/.../..    35 ENE AERO 33 ENE RMY N/A

5/19 Low temp since midnight is 43F; normal low is now 49F


DAILY RECORDS FOR MAY 2018

5/03/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

5/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001


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

RECORDS FOR MAY 19
HIGH 91F IN 1962
LOW 34F IN 2002
PRECIP 1.54 INCHES IN 1900
PEAK GUST 58 MPH NW IN 1964

RECORDS FOR MAY 20
HIGH 91F IN 1975,1996
LOW 37F IN 1948, 2002
PRECIP 1.65 INCHES IN 1969
PEAK GUST 57 MPH S IN 1963, WNW IN 1982

TODAY'S REPORT PREPARED BY: Lizzy Suzedell