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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, JULY 22, 2017  
ALL TIMES ARE IN EASTERN STANDARD TIME

SLIGHTLY COOLER TEMPERATURES AND HAZY CONDITIONS

The temperatures at Great Blue Hill today did not rise quite as high 
as they have been. The last 3 days all had a maximum temperature of 
90F, which means there was a heatwave. If the maximum temperature today 
does not reach 90F, then the heatwave will not continue. A maximum 
temperature of just 85F was reached by the 1:00 P.M. EST observation 
today. The maximum temperatures by 1:00 P.M. for every day of the 
heatwave were 88F-90F, so it is not as likely that the temperature 
will increase to 90 today. Last night, the temperature got down to a 
low of 70F. The heat has put the cumulative departure at 38F above 
normal (almost 2F per day) for the month of July. Temperatures are 
expected to finally cool down tomorrow.

Despite the hot temperatures, it has been pleasant due to relatively 
dry conditions. Dew points have stayed around 60F, with the relative 
humidity at 43% at 1:00 P.M. Broken altocumulus and few altostratus 
were present all day, and few cumulus moved in by the afternoon. 
Visibility was only at 30 miles in the afternoon due to haze. Winds 
have been fairly light. Before 7:00 A.M., winds were out of the WNW. 
From then until to 11:00 A.M., the wind was very calm. After 11:00 A.M., 
winds began to pick up and shift to the SW. The peak gust measured 
since 7:00 A.M. was 16 MPH out of the SW at 1:17 P.M.


Today's Observations:

7 A.M.
Weather: Broken altocumulus, few altostratus in all directions
Temperature: 71F; Dew Point: 60F; Wind: WNW at 7 kts
Sea-level pressure: 29.89 ins. Hg, rising, then more quickly
Visibility: 40 miles, distant haze in all directions
6-hr Max temp: 73F
6-hr Min temp: 70F
24-hr precip: 0.00 in. 
BHO SA 1155 E180 BKN 40 122/71/60/3007/989/ FEW AS ALQDS DSNT HZ 
ALQDS/  8/070 53015 10073 20070

10 A.M.
Weather: Broken altocumulus, few altostratus in all directions
Temperature: 79F; Dew Point: 61F; Wind: Estimated NNW at 2 kts,
Wind Speed: Light
Sea-level pressure: 29.88 ins. Hg, rising, then falling
Visibility: 30 miles, hazy
BHO SA 1455 E180 BKN 30 119/79/61/E3402/988/ FEW AS ALQDS HAZY 
WND LGT/ 8/07 58003

1 P.M. 
Weather: Broken altocumulus, few cumulus in all directions, few 
altostratus  in all directions
Temperature: 85F; Dew Point: 60F; Wind: SW at 7 kts
Sea-level pressure: 29.86 ins. Hg, falling, then more quickly
Visibility: 30 miles, hazy
6-hr Max temp: 85F
6-hr Min temp: 71F
BHO SA 1755 E180 BKN 30 111/85/60/2107/986/ FEW CU ALQDS FEW AS 
ALQDS HAZY/ 8/070 58008 10085 20071


SUMMARY FOR FRIDAY, JULY 21, 2017
 
TEMPERATURE (DEGREES F)
MAX.....90   NORMAL.....81
MIN.....68   NORMAL.....63
MEAN....79   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL.........................+7
TOTAL DEPARTURE FOR THE MONTH........................+38 [+1.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............14   DEPARTURE..........+6
TOTAL COOLING UNITS FOR THE MONTH.............184   DEPARTURE.........+39
TOTAL COOLING UNITS FOR THE SEASON............385   DEPARTURE........+111
TOTAL COOLING UNITS LAST SEASON TO DATE.......334   DEPARTURE.........+51

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................26 W AT  4:52 P.M.
                   AERO........................26 W AT  4:52 P.M.
                   ASOS........................27 W AT  4:56 P.M.
                   DAVIS.......................26 W AT  4:55 P.M. RMY XX
FASTEST MILE FOR YESTERDAY.....................20 W AT  4:50 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................20 W AT 10:02 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.................19 W AT  4:53 P.M.
AVERAGE WIND SPEED AND DIRECTION.............10.1 W
                   ASOS......................10.3
                   DAVIS......................8.8 W [279 DEG.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.13
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........1.58  DEPARTURE......-1.01
                         ASOS..............1.55
TOTAL PRECIPITATION FOR THE YEAR..........32.95  DEPARTURE......+3.39
                         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 85/68/77/+5/0.07/.../..               23 S   AERO 23 S   RMY 23
7/19 90/70/80/+8/0.00/.../..               22 SW  AERO 22 SW* RMY 22
7/20 90/70/80/+8/0.00/.../..               21 WSW AERO 22 WSW RMY 21
7/21 90/68/79/+7/0.00/.../..               26 W   AERO 26 W   RMY 27

7/22 Low temp since midnight is 70F; 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 22
HIGH 99F IN 1926, 2011
LOW 52F IN 1890
PRECIP 1.73 INS IN 1900 
PEAK GUST 55 MPH IN 1983

RECORDS FOR JULY 23
HIGH 99F IN 1952
LOW 51F IN 1923,1977
PRECIP 1.82 INS IN 1953
PEAK GUST 54e MPH S IN 1946

TODAY'S REPORT PREPARED BY: Lizzy Suzedell