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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, JULY 24, 2018 
ALL TIMES ARE IN EASTERN STANDARD TIME

ANOTHER HUMID DAY WITH SCATTERED SHOWERS... 

The day began with cloudy skies, humid air and
fog that obscured visibility down to 20 miles.
We observed a couple showers between 8:00 A.M. and 
10:00 A.M. The showers were quick moving only leaving 
a trace of precipitation on top of Great Blue Hill. 
After another humid morning dew points began to drop 
and we had 59% humidity at 1:00 P.M. A distant haze 
lingered after the fog for 40 miles of visibility at 
1:00 P.M. 
With a warm southerly wind temperatures have been 
above normal today with a max so far of 85F degrees. 
This is 4 degrees above the daily normal of 81F. We 
had another breezy afternoon with frequent gust over 
22 kts (25 MPH). 

Today's Observations:

7 A.M.
Weather: Broken stratocumulus, broken stratus
Temperature: 74F; Dew Point: 71F; Wind: SSE at 8G18 kts
Sea-level pressure: 30.31 ins. Hg, rising, then more slowly
Visibility: 20 miles, distant fog in all directions 
6-hr Max temp: 74F
6-hr Min temp: 72F
24-hr Precip: 0.06 ins.
BHO SA 1155 E13 BKN E20 BKN 20 263/74/71/1509G18/031/ DSNT 
FG ALQDS/ 8/600 51004 MANUAL 70006 ASOS 70005 10074 20072 

10 A.M.
Weather: Light drizzle, scattered nimbostratus, 
broken stratocumulus, broken stratus
Temperature: 80F; Dew Point: 72F; Wind: S at 11G22 kts
Sea-level pressure: 30.29 ins. Hg, falling unsteadily 
Visibility: 35 miles, distant fog in all directions
3-hr Precip: Trace 
BHO SA 1455 34 SCT E40 BKN E50 BKN 35L- 258/80/72/1911G22/029/ 
L-B45E59 DSNT FG ALQDS/ 8/620 58005 MANUAL 600//  

1 P.M.
Weather: Scattered cumulus, broken stratocumulus,
few towering cumulus S,W,WNW and ENE
Temperature: 85F; Dew Point: 69F; Wind: S at 17G24 kts
Sea-level pressure: 30.27 ins. Hg, falling steadily 
Visibility: 40 miles, distant haze in all directions
6-hr Max temp: 85F
6-hr Min temp: 73F
6-hr precip: Trace
BHO SA 1755 40 SCT E60 BKN 40 249/85/69/1817G24/027/ FEW 
TCU S,W,WNW AND ENE DSNT HZ ALQDS/ 8/800 58009 MANUAL 600//  
10085 20073

SUMMARY FOR MONDAY, JULY 23, 2018 

TEMPERATURE (DEGREES F)
MAX.....82   NORMAL.....81
MIN.....71   NORMAL.....63
MEAN....77   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL.........................+5
TOTAL DEPARTURE FOR THE MONTH........................+51 [+2.0 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............12   DEPARTURE..........+4
TOTAL COOLING UNITS FOR THE MONTH.............203   DEPARTURE.........+42
TOTAL COOLING UNITS FOR THE SEASON............362   DEPARTURE.........+72
TOTAL COOLING UNITS LAST SEASON TO DATE.......401   DEPARTURE.........-39

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................32 S   AT  9:03 A.M.
                   AERO.........................30 S   AT  9:01 A.M.
                   ASOS.........................33 S   AT  4:42 P.M.
                   DAVIS........................34 S   AT 10:28 A.M. RMY 32
FASTEST MILE FOR YESTERDAY......................22 SSE AT 12:14 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE...................22 S   AT  1:41 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE..................22 SSE AT  8 :00 A.M. 
AVERAGE WIND SPEED AND DIRECTION..............15.8 SSE
                   ASOS.......................14.2
                   DAVIS......................15.0 S  [178 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.06  DEPARTURE......-0.08
                         ASOS..............0.05
TOTAL PRECIPITATION FOR THE MONTH..........3.03  DEPARTURE......+0.17
                         ASOS..............3.06 
TOTAL PRECIPITATION FOR THE YEAR..........33.20  DEPARTURE......+3.55
                         ASOS.............34.79

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 Low temp since midnight is 72F; 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 24
HIGH 96F IN 1987
LOW 49F IN 1893,1912
PRECIP 2.27 INS IN 2008
PEAK GUST 46 MPH NE IN 2009

RECORDS FOR JULY 25
HIGH 96F IN 2016
LOW 51F IN 1901,1953
PRECIP 2.25 INS IN 1990
PEAK GUST 88 MPH NW IN 1972

TODAY'S REPORT PREPARED BY: Kaitlin Geagan