BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA   DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, SEPTEMBER 17, 2016  ALL TIMES ARE IN EASTERN STANDARD TIME   ANOTHER COOL MID-SEPTEMBER EARLY MORNING TODAY NOT QUITE AS COOL AS 24 HOURS AGO AS HIGH PRESSURE MOVES OFF TO EAST A SOUTHWESTERLY WIND FLOW WILL BRING WARMER TEMPERATURES     Here at the summit the morning low temperature matched the 54F which we recorded 24 hours ago this morning. That is exactly the normal low for this date. Eastern Massachusetts locations subject to radiational cooling were again down in the low 40's with even a few upper 30's being recorded including nearby Norwood Airport which again dropped into the upper 30's. My Hingham station had a low of 45 yesterday morning and 46 this morning.   Patches of shallow dense ground fog could be seen dissipating well to our west and there was a patch of steam fog over Ponkapoag Pond just to our south-southeast.   7 A.M. Weather: Thin scattered cirrus and thin broken cirrus, narrow line of stratocumulus distant E-SW, thin patch of steam fog dissipating over the pond in vicinity SSE, patches of shallow dense ground fog dissipated to the distant WSW-W Temperature: 57F; Dew Point: 50F; Wind: SW at 7 kts, Sea-level pressure: 30.29 ins. Hg, rising slightly Visibility: 50 miles, except 60 miles W-NW, 20 miles S 6-hr Max temp: 57F 6-hr Min temp: 54F 24-hr precip: 0.00 in. BHO SA 1155 250 -SCT 300 -BKN 50 258/57/50/2307/029/ LONG NARROW PTCH SC LYR XTDNG DSNT E-SW FEW PTCHS LWR CI PTCH STEAM FG DSSPTG OVR POND VC SSE PTCHS DNS SHLW GF DSNT WSW-W DSSPTD PST HR VSBY W-NW 60 S 20/ 8/501 53004 10057 20054   10 A.M. Weather: Scattered cumulus fractus/cumulus, thin scattered cirrus, thin broken cirrus, few lower cirrus   Temperature: 70F; Dew Point: 55F; Wind: SSW at 11G17 kts, Wind: Direction variability SSE-WSW Sea-level pressure: 30.27 ins. Hg, falling then more slowly Visibility: 60 miles BHO SA 1455 25 SCT 250 -SCT 300 -BKN 60 252/70/55/2011G17/027/ CUFRA/CU FRMG WND 15V24/ 8/101 56006    1 P.M. Weather: Scattered cumulus, thin scattered cirrus, thin broken cirrus Temperature: 76F; Dew Point: 55F; Wind: SSW at 13G20 kts, Wind: Direction variability SSE-WSW Sea-level pressure: 30.20 ins. Hg, falling, then more quickly Visibility: 55 miles 6-hr Max. temp: 76F 6-hr Min. temp: 57F BHO SA 1755 37 SCT 250 -SCT 300 -BKN 55 227/76/55/1813G20/020/ LGT DSNT HZ WND 15V24/ 8/101 58025 10076 20057   SUMMARY FOR FRIDAY, SEPTEMBER 16, 2016 TEMPERATURE (DEGREES F) MAX.....74   NORMAL.....72 MIN.....54   NORMAL.....55 MEAN....64   NORMAL.....63   DEPARTURE FROM 30-YEAR NORMAL........................+1 TOTAL DEPARTURE FOR THE MONTH.......................+45 [+2.6 DEGREES/DAY]   COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY...............0   DEPARTURE..........-3 TOTAL COOLING UNITS FOR THE MONTH..............63   DEPARTURE.........+18 TOTAL COOLING UNITS FOR THE SEASON............855   DEPARTURE........+273 TOTAL COOLING UNITS LAST SEASON TO DATE.......770   DIFFERENCE........+85   HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............1   DEPARTURE..........+2 TOTAL HEATING UNITS FOR THE MONTH...............5   DEPARTURE.........-29 TOTAL HEATING UNITS FOR THE SEASON.............16   DEPARTURE.........-44 TOTAL HEATING UNITS LAST SEASON TO DATE.........6   DIFFERENCE........+10   PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................23 SSE AT  5:46 P.M.                      ASOS........................22 SSE AT  5:46 P.M.                     DAVIS.......................22 SSE AT  5:45 P.M. RMY 24 FASTEST MILE FOR YESTERDAY.....................14 SSW AT  9:44 P.M.     MAXIMUM 2-MINUTE ASOS AVERAGE..................15 SSW AT  9:46 P.M.  MAXIMUM 2-MINUTE DAVIS AVERAGE.................15 SSE AT  5:47 P.M.   AVERAGE WIND SPEED AND DIRECTION..............8.1 S                     ASOS........................8.5                    DAVIS.......................7.4 S [190 Deg.] * Last of several 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..........1.31  DEPARTURE......-0.71                          ASOS..............1.30 TOTAL PRECIPITATION FOR THE YEAR..........26.28  DEPARTURE.....-10.76                          ASOS.............26.57   PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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   9/1  72/64/68/0/0.09/000/00                  21 NNW AERO 16 NNW RMY 20 9/2  76/58/67/-1/0.00/738/94                 23 ENE AERO 17 NE  RMY 23 9/3  71/56/64/-3/0.00/368/47                 16 E   AERO 12 E   RMY N/A 9/4  71/58/65/-2/0.00/740/95                 28 NE  AERO 21 NE  RMY 27 9/5  73/57/65/-2/0.52/241/31                 42 NNE AER0 33 NNE RMY 43  9/6  70/61/66/-1/0.54/046/06                 32 N   AERO 23 NNE RMY N/A  9/7  78/66/72/+6/0.05/339/44                 21 NE* AERO 15 NE* RMY 21 9/8  79/65/72/+6/T/276/36                    22 S   AERO 15 S   RMY 23 9/9  90/69/80/+14/T/421/55                   23 W   AERO 24 W   RMY 25  9/10 82/71/77/+12/T/.../..                   25 S   AERO 18 S   RMY 32 9/11 79/59/69/+4/0.10/.../..                 39 WNW AERO 30 WNW RMY 43 9/12 76/53/65/0/0.00/.../..                  18 SW* AERO 13 WNW RMY 19 9/13 81/57/69/0/0.00/.../..                  25 SSW AERO  M     RMY 26 9/14 87/58/73/+5/T/.../..                    35 NNW AERO  M     RMY 35 9/15 67/52/60/+9/0.00/.../..                 21 NE  AERO  M     RMY 20 9/16 74/54/64/+1/0.00/.../..                 23 SSE AERO  M     RMY 24     9/17 Low temp since midnight is 54F; normal low is now 54F   DAILY RECORDS FOR SEPTEMBER 2016   9/10/16: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F,          BREAKS PREVIOUS RECORD OF 69F SET IN 1915, 1931, AND 1989   DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR SEPTEMBER 17 HIGH 87F IN 2015 LOW 38F IN 1959 PRECIP 2.73 INCHES IN 1933 PEAK GUST 60 MPH WNW IN 1999   RECORDS FOR SEPTEMBER 18 HIGH 88F IN 1906 LOW 36F IN 1919 PRECIP 4.25 INCHES IN 1996 PEAK GUST 77e MPH WNW IN 1948   TODAY'S REPORT PREPARED BY: Robert Skilling