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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JULY 15, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME
 
WARM, HUMID WEATHER TODAY WITH A FEW SHOWERS
COLD FRONT TO BRING RELIEF FOR TOMORROW
 
Once again today, warm and oppressively humid conditions have been in place.
We've also seen another round of localized showers and downpours today.
Numerous small cells developed from late morning into the afternoon, although
they've died down some into the mid-afternoon.  So far, just a trace of rain
has fallen at the summit.  Showers yesterday and last night produced a total
of just 0.07 inches of rain here, but 0.57 inches of rain was recorded in less
than half an hour last night in a downpour in nearby Hingham.  The morning
began foggy, but this quickly burned off and the Sun has been out
intermittently during the day, with enough breaks of sunshine to propel
temperatures into the low-mid 80s, with a high for the day so far of 84F after
a warm morning low of 69F.
 
A cold front is helping to trigger today's shower activity, and it will also
lead to significant relief from the humidity of the past few days, with
cooler and much drier air forecast for tomorrow.
 
Today's Observations:

7 A.M.
Weather: Sky obscured by dense fog, few stratus fractus below summit,
ceiling occasionally visible ENE
Temperature: 71F; Dew Point: 70F; Wind: W at 7 kts
Sea-level pressure: 29.65 ins. Hg, rising then rising more rapidly
Visibility: 1/4 mile, dense fog
6-hr Max temp: 71F
6-hr Min temp: 69F
24-hr precip: 0.07 inches
BHO SA 1155 W3 X 1/4F 040/71/70/2607/965/ FEW STFRA BLO SMT
CLG OCNLY VSBL ENE/ 8//// 53015 ASOS 70006 MANUAL 70007 10071 20069
 
10 A.M.
Weather: Broken cumulus and moderate cumulus, broken cirrus, rain showers
SW and NW moving E, light rain shower began 9:39 A.M., ended 9:53 A.M.
Temperature: 79F; Dew Point: 73F; Wind: WNW at 6 kts
Sea-level pressure: 29.66 ins. Hg, rising slightly
Visibility: 40 miles, distant haze
3-hr precip: Trace
BHO SA 1455 E20 BKN 250 BKN 40 045/79/73/2906/966/ SHRA SW AND NW MVNG E
RW-B39E54 DSNT HZ/ 8/201 53005 MANUAL 6000/
 
1 P.M.
Weather: Broken cumulus and moderate cumulus, broken cirrus, few cumulus
congestus S-NW
Temperature: 82F; Dew Point: 70F; Wind: estimated ENE at 5 kts,
Wind: Light and variable
Sea-level pressure: 29.66 ins. Hg, about steady 
Visibility: 40 miles, distant haze
6-hr Max temp: 84F
6-hr Min temp: 71F
6-hr precip: Trace
BHO SA 1755 E25 BKN 250 BKN 40 043/82/70/E0605/966/ FEW CU CNGSTS S-NW
DSNT HZ WND L/V/ 8/201 55002 MANUAL 6000/ 10084 20071
 
SUMMARY FOR TUESDAY, JULY 14, 2015
  
TEMPERATURE (DEGREES F)
MAX.....81   NORMAL.....81
MIN.....64   NORMAL.....63
MEAN....73   NORMAL.....72

DEPARTURE FROM 30-YEAR NORMAL........................+1
TOTAL DEPARTURE FOR THE MONTH.......................+12 [+0.7 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............8   DEPARTURE..........+1
TOTAL COOLING UNITS FOR THE MONTH.............101   DEPARTURE..........+8
TOTAL COOLING UNITS FOR THE SEASON............239   DEPARTURE.........+17
TOTAL COOLING UNITS LAST SEASON TO DATE.......236   DIFFERENCE.........+3

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...................25   S    AT   2:21 P.M.*              
                   ASOS........................27   S    AT   2:21 P.M.
                   DAVIS.......................25   SE   AT  10:21 A.M. RMY 27
FASTEST MILE FOR YESTERDAY.....................19   SSE  AT  10:17 A.M.*         
MAXIMUM 2-MINUTE ASOS AVERAGE..................20   S    AT   2:27 P.M.                
MAXIMUM 2-MINUTE DAVIS AVERAGE.................19   S    AT   2:27 P.M.        
AVERAGE WIND SPEED AND DIRECTION..............10.5  S
                   ASOS.......................10.0
                   DAVIS.......................9.7 SSE [164 deg.]
* Last of several occurrences...
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.07  DEPARTURE.....-0.07
                         ASOS...............0.06
TOTAL PRECIPITATION FOR THE MONTH...........2.71  DEPARTURE.....+1.05
                         ASOS...............2.75
TOTAL PRECIPITATION FOR THE YEAR.......... 26.98  DEPARTURE.....-1.65
                         ASOS...............N/A ***
 
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR JULY CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY 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
 
7/1  80/63/72/+2/0.59/.../..               30 SSE RMY 33  TSTM
7/2  78/60/69/-1/0.00/.../..               23 WNW RMY N/A
7/3  79/58/69/-2/0.00/.../..               17 SSW RMY 17
7/4  74/61/68/-3/T/.../..                  16 S   RMY N/A
7/5  82/58/70/-1/0.00/.../..               20 WSW RMY 20 
7/6  85/64/75/+4/0.00/.../..               20 S   RMY 21
7/7  84/65/75/+4/0.02/.../..               35 S   RMY 40
7/8  87/68/78/+6/T/.../..                  23 NE  RMY N/A
7/9  73/61/67/-5/..../.../..               24 NE  RMY 25
7/10 80/59/70/-2/..../.../..               18 W   RMY N/A TSTM
7/11 84/61/73/+1/0.00/.../..               21 NW  RMY 19
7/12 88/67/78/+6/0.00/.../..               20 W   RMY 17
7/13 82/66/74/+2/0.00/.../..               21 E   RMY 20
7/14 81/64/73/+1/..../.../..               25 S   RMY 27
 
7/15 low since midnight is 69F; normal low is now 63F

DAILY RECORDS FOR JULY 2015
 
7/10- NEW RECORD DAILY PRECIPITATION PENDING OF X.XX in 2015
surpasses previous record of 1.68 in. in 1933

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR JULY 15
HIGH 94F IN 1995
LOW 50F IN 1929, 1930
PRECIP 1.64 INS IN 1896
WIND 71 MPH WNW IN 2002
 
RECORDS FOR JULY 16
HIGH 94F IN 1968, 1980, 1983, 1999
LOW 50F IN 1889, 1903
PRECIP 0.97 INS IN 2014
WIND 48e MPH SW 1944
 
TODAY'S REPORT PREPARED BY: Jonathan O'Brien