BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, SEPTEMBER 27, 2016 ALL TIMES ARE IN EASTERN STANDARD TIME COLD FRONT PUSHES THROUGH THIS MORNING AND BRINGS MUCH NEEDED PRECIP. A light rain began early this morning and continued until approximately 7:45AM EST totaling 0.31 in. of precip. for today so far. The cold front is expected to stall near the coast and produce more rain showers this evening. Thick fog blanketed the observatory this morning but gradually cleared away to leave us with 70 miles visibility by the 1:00PM EST ob. Temperatures were slightly above normal today as the overnight low of 55F occurred before midnight and began slowly warming to a max. of 68F by 1:00PM. 7 A.M. Weather: Light rain, fog Temperature: 60F; Dew Point: 60F; Wind: W at 4 kts, Wind: Light and variable Sea-level pressure: 29.91 ins. Hg, falling then steady Visibility: 1/8 mile 6-hr Max temp: 61F 6-hr Min temp: 58F 24-hr precip: 0.28 in. BHO SA 1155 W2 X 1/8R-F 127/60/60/2604/991/ WND L/V/ 8//// 56005 ASOS 70029 MANUAL 70028 10061 20058 10 A.M. Weather: Few cumulus fractus in all directions, broken altocumulus, broken altostratus Temperature: 64F; Dew Point: 63F; Wind: WNW at 5 kts, Wind Speed: Light Sea-level pressure: 29.91 ins. Hg, falling then rising Visibility: 20 miles 3-hr precip: 0.03 in. BHO SA 1455 E140 BKN 200 BKN 20 129/64/63/2905/991/ FEW CUFRA ALQDS WND LGT/ 8/710 53002 MANUAL 6003/ ASOS 60003 1 P.M. Weather: Scattered cumulus, overcast altostratus Temperature: 67F; Dew Point: 59F; Wind: estimated W at 3 kts, Wind Speed: Light Sea-level pressure: 29.91 ins. Hg, falling, then more quickly Visibility: 70 miles 6-hr Max. temp: 68F 6-hr Min. temp: 58F 6-hr precip: 0.03 in. BHO SA 1755 18 SCT E140 OVC 70 127/67/59/E2703/991/ WND LGT/ 8/11/ 56002 MANUAL 6003/ ASOS 60003 10068 20058 SUMMARY FOR MONDAY, SEPTEMBER 26, 2016 TEMPERATURE (DEGREES F) MAX.....68 NORMAL.....68 MIN.....43 NORMAL.....51 MEAN....56 NORMAL.....59 DEPARTURE FROM 30-YEAR NORMAL........................-3 TOTAL DEPARTURE FOR THE MONTH.......................+96 [+3.5 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY...............0 DEPARTURE..........-1 TOTAL COOLING UNITS FOR THE MONTH.............102 DEPARTURE.........+45 TOTAL COOLING UNITS FOR THE SEASON............894 DEPARTURE........+300 TOTAL COOLING UNITS LAST SEASON TO DATE.......797 DIFFERENCE........+97 HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............9 DEPARTURE..........+2 TOTAL HEATING UNITS FOR THE MONTH..............33 DEPARTURE.........-54 TOTAL HEATING UNITS FOR THE SEASON.............43 DEPARTURE.........-69 TOTAL HEATING UNITS LAST SEASON TO DATE........36 DIFFERENCE.........+7 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................25 S AT 7:24 P.M. ASOS........................25 SSW AT 7:24 P.M. DAVIS.......................24 S AT 7:24 P.M. RMY 25 FASTEST MILE FOR YESTERDAY.....................19 S AT 7:30 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................20 SSW AT 7:24 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................18 S AT 7:23 P.M. AVERAGE WIND SPEED AND DIRECTION..............8.9 S ASOS.......................9.2 DAVIS......................8.1 SW [220 Deg.] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.28 DEPARTURE......+0.13 ASOS..............0.29 TOTAL PRECIPITATION FOR THE MONTH..........1.94 DEPARTURE......-1.53 ASOS..............1.95 TOTAL PRECIPITATION FOR THE YEAR..........26.91 DEPARTURE.....-11.58 ASOS.............27.22 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 72/56/64/-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/229/30 25 S AERO 18 S RMY 32 9/11 79/59/69/+4/0.10/365/48 39 WNW AERO 30 WNW RMY 43 9/12 76/53/65/0/0.00/749/99 18 SW* AERO 13 WNW RMY 19 9/13 81/57/69/+5/0.00/739/98 25 SSW AERO M RMY 26 9/14 87/58/73/+9/T/526/70 35 NNW AERO M RMY 35 9/15 67/52/60/-4/0.00/531/71 21 NE AERO M RMY 20 9/16 74/54/64/+1/0.00/567/76 23 SSE AERO M RMY 24 9/17 77/54/66/+3/0.00/676/91 28 S AERO M RMY 28 9/18 79/63/71/+9/T/133/18 30 SW AERO M RMY 33 9/19 73/67/70/+8/0.16/000/00 25 S AERO M RMY N/A 9/20 81/66/74/+12/0.00/316/43 16 WSW*AERO M RMY N/A 9/21 81/64/73/+12/T/541/74 20 WNW AERO M RMY 18 9/22 82/63/73/+12/0.00/700/96 23 S AERO M RMY 25 9/23 80/53/67/+7/0.16/.../.. 32 NE AERO M RMY 32 9/24 66/48/57/-3/0.03/.../.. 24 NW AERO M RMY 25 9/25 65/44/55/-5/0.00/.../.. 31 NW AERO M RMY 32 9/26 68/43/56/-3/0.00/.../.. 25 S AERO M RMY 25 9/27 Low temp since midnight is 57F; normal low is now 50F 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 27 HIGH 84F IN 1998, 2014 LOW 32F IN 1947 PRECIP 2.26 INCHES IN 1962 PEAK GUST 100 MPH SSE IN 1985 (HURRICANE GLORIA) RECORDS FOR SEPTEMBER 28 HIGH 86F IN 2014 LOW 33F IN 1897,1947 PRECIP 2.46 INCHES IN 2004 PEAK GUST 69 MPH NE IN 1962 TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle