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

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

THUNDERSTORM WITH HEAVY RAINFALL YESTERDAY AFTERNOON 
AND A FOGGY START TO A SO FAR DRY DAY...

We had a thunderstorm moved over the observatory yesterday
afternoon leaving 0.61 inches of rainfall, which was heavy
at times. Today has been dry so far with a dense fog to 
begin the day that dissipated before 10 A.M. A distant haze
lingered and we could see a max of 30 miles by 1:00 P.M. 
Although humidity was lower today with dew points continuing 
to be in the low 70's the air still feels sticky. The wind 
began the day coming from the SSW and shifted to coming from 
the S this afternoon. So far both high and low temperatures 
are above normal with and overnight low of 69F and a high max 
of 87F, both are 6 degrees above the daily normals of 63F and 
81F. As of now July is trending for above normal temperatures,
precipitation, and sunshine.

Today's Observations:

7 A.M.
Weather: Fog, broken stratus  
Temperature: 71F; Dew Point: 71F; Wind: S at 8G14 kts
Sea-level pressure: 30.01 ins. Hg, rising, then more rapidly  
Visibility: 5 miles prevailing, variable 1 to 3 miles   
6-hr Max temp: 71F
6-hr Min temp: 69F
24-hr Precip: 0.61 ins. 
BHO SA 1155 E5 BKN 5F 162/71/71/1808G14/001/ VSBY 1V3/ 
8/6// 53015 MANUAL 70061 ASOS 70061 10071 20069

10 A.M.
Weather: Scattered cirrostratus, few distant cumulus SSE-NNW
Temperature: 82F; Dew Point: 72F; Wind: SSW at 8G12 kts
Sea-level pressure: 30.02 ins. Hg, rising unsteadily
Visibility: 25 miles, hazy
3-hr Precip: 0.00 ins.  
BHO SA 1455 200 SCT 25 167/82/72/2108G12/002/ FEW CU DSNT 
SSE-NNW HAZY/ 8/105 51005 

1 P.M.
Weather: Scattered towering cumulus, scattered cirrostratus 
Temperature: 85F; Dew Point: 70F; Wind: S at 9G17 kts
Sea-level pressure: 29.97 ins. Hg, falling, then more slowly 
Visibility: 30 miles, hazy
6-hr Max temp: 87F
6-hr Min temp: 71F
6-hr precip: 0.00 ins. 
BHO SA 1755 45 SCT 200 SCT 30 158/85/70/1909G17/997/ 
HAZY/ 8/205 58009 10087 20071  

SUMMARY FOR THURSDAY, JULY 26, 2018 

TEMPERATURE (DEGREES F)
MAX.....83   NORMAL.....81
MIN.....69   NORMAL.....63
MEAN....76   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL.........................+4
TOTAL DEPARTURE FOR THE MONTH........................+67 [+2.4 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............11   DEPARTURE..........+3
TOTAL COOLING UNITS FOR THE MONTH.............240   DEPARTURE.........+55
TOTAL COOLING UNITS FOR THE SEASON............399   DEPARTURE.........+85
TOTAL COOLING UNITS LAST SEASON TO DATE.......403   DEPARTURE..........-4

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................41 SSW AT 5:05 A.M.
                   AERO.........................39 SSW AT 4:51 A.M.
                   ASOS.........................41 S   AT 5:05 A.M.
                   DAVIS........................40 SSW AT 5:06 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY......................32 SSW AT 4:51 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................30 S   AT 4:53 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................28 S   AT 4:53 A.M. 
AVERAGE WIND SPEED AND DIRECTION..............13.6 SSW
                   ASOS.......................13.3
                   DAVIS......................12.8 SSW [213 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.61  DEPARTURE......+0.47
                         ASOS..............0.61
TOTAL PRECIPITATION FOR THE MONTH..........3.83  DEPARTURE......+0.56
                         ASOS..............3.85 
TOTAL PRECIPITATION FOR THE YEAR..........34.00  DEPARTURE......+3.94
                         ASOS.............35.58

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

7/01 94/72/83/+13/0.00/667/73       21 ESE AERO 18 ESE RMY 19 
7/02 90/68/79/+9/0.00/858/94        21 S   AERO 21 S   RMY 22
7/03 94/69/82/+11/0.00/657/72       20 SSW AERO 18 SW  RMY 19 TSTM
7/04 89/73/81/+10/0.00/884/97       17 NE  AERO 15 NE  RMY 16
7/05 91/73/82/+11/0.00/865/95       29 SSW AERO 28 SSW RMY N/A
7/06 80/59/70/-1/0.56/018/02        37 NNW AERO 38 SW  RMY 40 TSTM
7/07 78/54/66/-5/0.00/900/99        22 N   AERO 18 N   RMY N/A 
7/08 83/57/70/-2/0.00/890/98        23 S   AERO 21 S   RMY 22  
7/09 88/60/74/+2/0.00/852/94        23 SW  AERO 23 SW  RMY 24 
7/10 91/63/77/+5/0.10/751/83        24 W   AERO 22 W   RMY N/A
7/11 73/62/68/-4/0.63/705/78        28 NE  AERO 25 NE  RMY 27 TSTM
7/12 77/56/67/-5/0.00/867/96        16 NW  AERO 15 NW  RMY N/A 
7/13 84/61/73/+1/0.00/568/63        23 SSE AERO 23 SSE RMY 24
7/14 80/61/71/-1/0.00/540/60        18 S   AERO 16 S   RMY 19
7/15 84/65/75/+3/T/521/58           16 S   AERO 15 S   RMY 14 
7/16 83/67/75/+3/0.00/682/76        23 S   AERO 23 S   RMY 23 
7/17 88/67/78/+6/1.34/430/48        31 SW  AERO 30 SW  RMY 32 TSTM 
7/18 81/63/72/0/0.02/769/86         21 NW  AERO 22 NW  RMY 23 
7/19 80/56/68/-4/0.00/.../..        21 S   AERO 17 SSE RMY 19 
7/20 83/62/73/1/0.00/.../..         21 SE  AERO 17 ESE RMY 19
7/21 76/59/68/-4/..../.../..        23 ENE AERO 20 ENE RMY N/A
7/22 76/63/69/-3/..../.../..        29 ESE AERO 28 ESE RMY N/A
7/23 82/71/77/+5/..../.../..        32 S   AERO 30 S   RMY 32 
7/24 85/72/79/+7/T/.../..           31 S   AERO 29 S   RMY 29 
7/25 82/71/77/+5/..../.../..        35 SSE AERO 32 SSE RMY N/A 
7/26 83/69/76/+5/..../.../..        41 SSW AERO 39 SSW RMY N/A TSTM

7/26 Low temp since midnight is 69F; normal low is now 63F

DAILY RECORDS FOR JULY 2018

07/01/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 72F, 
          TIES PREVIOUS RECORD OF 72F SET IN 1968

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

RECORDS FOR JULY 27
HIGH 95F IN 1949, 1963
LOW 50F IN 1920, 2001
PRE 4.01 INS IN 1979
WIND 47 MPH ENE IN 1984

RECORDS FOR JULY 28
HIGH 97F IN 1931
LOW 49F IN 1903
PRECIP 3.32 INS IN 1911
PEAK GUST 62 MPH SW IN 2006

TODAY'S REPORT PREPARED BY: Kaitlin Geagan