BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, SEPTEMBER 15, 2016 ALL TIMES ARE IN EASTERN STANDARD TIME MOSTLY CLOUDY SKIES CLEAR AS HIGH PRESSURE MOVES EAST This morning started out cool and cloudy with broken stratocumulus during the 7:00AM EST observation. The temperature measured just 57F, only 5F above the overnight low of 52F. Skies gradually cleared as high pressure over the Great Lakes continued moving east leaving us with scattered cumulus at the 1:00PM observation. Yesterday's max. temp. of 87F was 15F above normal and occurred before the passage of a cold front. The front left the observatory with just a trace of precipitation. Temperatures have been much cooler today with the max. temp. at 1:00PM measuring 67F. 7 A.M. Weather: Broken stratocumulus Temperature: 57F; Dew Point: 48F; Wind: N at 7 kts Sea-level pressure: 30.26 ins. Hg, rising, then more quickly Visibility: 70 miles 6-hr Max temp: 57F 6-hr Min temp: 52F 24-hr precip: Trace BHO SA 1155 E42 BKN 70 246/57/48/3607/026/ 8/500 51019 10057 20052 10 A.M. Weather: Scattered cumulus, broken stratocumulus Temperature: 61F; Dew Point: 49F; Wind: NE at 9G17 kts Sea-level pressure: 30.30 ins. Hg, rising, then less quickly Visibility: 70 miles BHO SA 1455 22 SCT E42 BKN 70 260/61/49/0409G17/030/ 8/500 51014 1 P.M. Weather: Scattered cumulus Temperature: 66F; Dew Point: 49F; Wind: NE at 7 kts Sea-level pressure: 30.27 ins. Hg, falling, then more quickly Visibility: 70 miles 6-hr Max. temp: 67F 6-hr Min. temp: 56F BHO SA 1755 42 SCT 70 251/66/49/0507/027/ 8/100 58009 10067 20056 SUMMARY FOR WEDNESDAY, SEPTEMBER 14, 2016 TEMPERATURE (DEGREES F) MAX.....87 NORMAL.....72 MIN.....58 NORMAL.....55 MEAN....73 NORMAL.....64 DEPARTURE FROM 30-YEAR NORMAL........................+9 TOTAL DEPARTURE FOR THE MONTH.......................+47 [+3.2 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY...............8 DEPARTURE..........+6 TOTAL COOLING UNITS FOR THE MONTH..............63 DEPARTURE.........+22 TOTAL COOLING UNITS FOR THE SEASON............855 DEPARTURE........+277 TOTAL COOLING UNITS LAST SEASON TO DATE.......758 DIFFERENCE........+97 HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............0 DEPARTURE..........-3 TOTAL HEATING UNITS FOR THE MONTH...............0 DEPARTURE.........-28 TOTAL HEATING UNITS FOR THE SEASON.............10 DEPARTURE.........-43 TOTAL HEATING UNITS LAST SEASON TO DATE.........6 DIFFERENCE.........+4 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................35 NNW AT 8:12 P.M. ASOS........................34 NW AT 8:13 P.M. DAVIS.......................32 W AT 3:05 P.M. RMY 35 FASTEST MILE FOR YESTERDAY.....................25 W AT 3:06 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................24 W AT 3:09 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................24 W AT 3:09 P.M. AVERAGE WIND SPEED AND DIRECTION.............13.8 NNW ASOS......................13.5 DAVIS.....................12.1 WSW [250 Deg.] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...TRACE DEPARTURE......-0.14 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.31 DEPARTURE......-0.44 ASOS..............1.30 TOTAL PRECIPITATION FOR THE YEAR..........26.28 DEPARTURE.....-10.49 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 81/57/69/0.00/.../.. 25 SSW AERO M RMY 26 9/14 87/58/73/T/.../.. 35 NNW AERO M RMY 35 9/15 Low temp since midnight is 52F; normal low is now 55F 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 15 HIGH 89F IN 1931 LOW 35F IN 1913 PRECIP 3.93 INCHES IN 1904 (Extra-tropical storm making landfall in New England on 9/15/1904 passing east of BHO and bringing a storm total of 4.11 inches 9/14-15/1904) PEAK GUST 65e MPH NW, WSW IN 1944 (In the wake of Great Atlantic Hurricane) RECORDS FOR SEPTEMBER 16 HIGH 91F IN 1939,1941 LOW 39F IN 1984 PRECIP 5.12 INCHES IN 1933 (Hurricane) PEAK GUST 59 MPH SSE IN 1999 TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle