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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JULY 18, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME

AFTERNOON RAIN SHOWER PASSES BHO

Morning fog prevented visibility to be greater than 10
miles during the 7:00AM EST observation.  It quickly
cleared away to show hazy conditions which kept visibility
at 20-30 miles for the rest of the day.  A brief rain shower
fell between 11:50AM and 12:15PM EST which left 0.02 inches
of rain and caused the winds to shift north-northwest during
that time.  Warm temperatures continue, but dew points have
been slightly higher today as warm, moist air from the tropics
enters the region.


Today's Observations:

7 A.M.
Weather: Broken cumulus fractus, broken altocumulus
Temperature: 72F; Dew Point: 69F; Wind: S at 5 kts,
Wind speed: Light
Sea-level pressure: 30.13 ins. Hg, falling then rising
Visibility: 10 miles, distant fog in all directions
6-hr Max temp: 72F
6-hr Min temp: 68F
24-hr precip: 0.00 in. 
BHO SA 1155 E5 BKN 140 BKN 10 204/72/69/1905/013/ DSNT FG ALQDS 
WND LGT/ 8/710 53003 10072 20068

10 A.M.
Weather: Two layers of broken cumulus
Temperature: 78F; Dew Point: 68F; Wind: SSW at 4 kts,
Wind speed: Light
Sea-level pressure: 30.13 ins. Hg, rising then falling
Visibility: 20 miles, hazy
BHO SA 1455 E20 BKN 27 BKN 20 202/78/68/2104/013/ HAZY WND LGT/ 
8/100 58002

1 P.M. 
Weather: Scattered cumulus, broken altocumulus, light rain ending at
12:15PM EST
Temperature: 79F; Dew Point: 69F; Wind: SSW at 7 kts
Sea-level pressure: 30.09 ins. Hg, falling, then more quickly
Visibility: 30 miles, except 40 miles S, hazy
6-hr Max temp: 85F
6-hr Min temp: 72F
6-hour precip: 0.02 in.
BHO SA 1755 27 SCT E110 BKN 30 188/79/69/2107/009/ VSBY S 40 HAZY 
R-E15/ 8/280 58014 MANUAL 6002/ ASOS 60003 10085 20072


SUMMARY FOR MONDAY, JULY 17, 2017
 
TEMPERATURE (DEGREES F)
MAX.....84   NORMAL.....81
MIN.....68   NORMAL.....63
MEAN....76   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL.........................+4
TOTAL DEPARTURE FOR THE MONTH........................+10 [+1.5 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............11   DEPARTURE..........+4
TOTAL COOLING UNITS FOR THE MONTH.............128   DEPARTURE.........+14
TOTAL COOLING UNITS FOR THE SEASON............329   DEPARTURE.........+86
TOTAL COOLING UNITS LAST SEASON TO DATE.......291   DEPARTURE.........+38

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................24  S  AT 5:22 P.M.
                   AERO........................24  S  AT 5:25 P.M.*
                   ASOS........................25  S  AT 5:22 P.M.
                   DAVIS.......................26 SSW AT 5:20 P.M. RMY 25
FASTEST MILE FOR YESTERDAY.....................17  S  AT 5:21 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................18  S  AT 5:23 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................16  S  AT 5:23 P.M.
AVERAGE WIND SPEED AND DIRECTION..............9.5  S
                   ASOS.......................9.7
                   DAVIS......................7.6 S [192 DEG.]
*last of multiple occurrences

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..........1.51  DEPARTURE......-0.56
                         ASOS..............1.48
TOTAL PRECIPITATION FOR THE YEAR..........32.88  DEPARTURE......+3.84
                         ASOS...............N/A ***
*** ASOS annual total not available due to erroneous readings


PRELIMINARY CLIMATE SUMMARY FOR JULY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

7/1  85/67/76/+6/T/439/48                  35 S   AERO 37 S   RMY 38
7/2  87/69/78/+8/T/785/86                  25 W*  AERO 28 W*  RMY 27
7/3  85/67/76/+5/0.00/894/98               28 W*  AERO 29 W   RMY 30
7/4  84/62/73/+2/0.00/783/86               17 W   AERO 17 W   RMY 18
7/5  82/62/72/+1/0.00/855/94               20 S   AERO 20 ENE RMY 20
7/6  82/60/71/+0/0.00/664/73               21 SSW AERO 22 SSW RMY 21
7/7  71/60/66/-5/0.63/000/00               28 ENE AERO 28 ENE RMY 27
7/8  84/61/73/+1/0.15/463/51               30 SW* AERO 32 SSW RMY 33 TSTM
7/9  81/60/71/-1/0.00/897/99               26 W   AERO 26 W   RMY 26
7/10 85/63/74/+2/T/751/83                  25 SW  AERO 25 S   RMY 26
7/11 82/66/74/+2/0.25/253/28               24 S   AERO 24 S   RMY N/A
7/12 85/68/77/+5/0.43/325/36               23 NE  AERO 22 NE  RMY 23 TSTM
7/13 68/55/62/-10/0.03/000/00              28 NNE AERO 28 NE  RMY 29
7/14 63/56/60/-12/0.02/.../..              15 E   AERO 14 E   RMY 14
7/15 80/60/70/-2/0.00/.../..               18 S   AERO 16 S   RMY 18
7/16 87/64/76/+4/0.00/.../..               18 SSE AERO 16 E   RMY 17
7/17 84/68/76/+4/0.00/.../..               25 S   AERO 25 S*  RMY 25

7/18 Low temp since midnight is 68F; normal low is now 63F


DAILY RECORDS FOR JULY

None so far.


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

RECORDS FOR JULY 18
HIGH 96F IN 1991, 1999
LOW 54F IN 1892, 1956, 1971
PRECIP 1.65 INS IN 2000
WIND 43e MPH SW IN 1949

RECORDS FOR JULY 19
HIGH 96F IN 1977, 1991
LOW 50F IN 1890
PRECIP 1.10 INS IN 1951
WIND 63 MPH SSW IN 1982

TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle