BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, OCTOBER 6, 2016 ALL TIMES ARE IN EASTERN STANDARD TIME SUNNY SKIES AND WARM TEMPERATURES MAKE FOR A GREAT FALL DAY Thin ground fog caught beneath a temperature inversion was observed at the 7:00AM EST observation. Clear skies and warming temperatures allowed the fog to quickly dissipate and improve visibility to 70 miles in all directions by the late morning. Dew points remained in the 40s as temps climbed to a max. of 69F by 1:00PM. Winds were light and changed direction from NE to SW shortly before noon. PRELIMINARY STATS FOR SEPTEMBER 2016 TEMPERATURE, Deg. F Avg. Max. 74.0 [+2.4] Avg. Min. 57.9 [+3.3] Mean 66.0 [+2.9] 24-hour corrected mean: 65.2 Max. for month: 90F on 9th Min. for month: 43F on 26th HEATING DEGREE DAYS Total heating units: 65 [-52] Total for the season: 75 [-67] Total for last season: 43 COOLING DEGREE DAYS Total cooling units: 102 [+42] Total for the season: 894 [+297] Total for last season: 810 PRECIPITATION, Inches Total: 2.35 [-1.71] Greatest in 24 hrs: 1.06 on the 5-6th WIND, mph Avg. uncorrected wind speed: 10.8 Avg. corrected wind speed: 11.2 Prevailing wind direction: S at 14% Peak gust and direction: 42 NNE on 5th SUNSHINE: Campbell-Stokes card minutes: 10980 mins. of possible 21582 or 51% Astronomical total minutes: 11407 mins. of possible 22407 or 51% The 24-hour corrected mean temperature for September of 65.2 deg F is the seventh warmest on record and the warmest only since last September, which was the warmest on record. BHO Warmest Septembers, deg F (1885-2016): 1) 67.2 in 2015 2) 66.1 in 1961 3) 65.5 in 2005 4) 65.4 in 1999 65.4 in 2010 6) 65.3 in 1930 7) 65.2 in 2016 8) 65.0 in 2002 7 A.M. Weather: Few distant cumulus NE-SE, few cirrus in all directions, thin radiation fog below inversion Temperature: 50F; Dew Point: 47F; Wind: N at 4 kts, Wind Speed: Light Sea-level pressure: 30.32 ins. Hg, rising, then more quickly Visibility: 30 miles, except 70 miles SW-NNW 6-hr Max temp: 50F 6-hr Min temp: 46F 24-hr precip: 0.00 in. BHO SA 1155 CLR 30 267/50/47/3504/032/ FEW DSNT CU NE-SE FEW CI ALQDS VSBY SW-NNW 70 THN GF BLO INVSN WND LGT/ 8/101 53006 10050 20046 10 A.M. Weather:Few distant cumulus ENE-SSE Temperature: 62F; Dew Point: 46F; Wind: estimated ENE at 1 kt, Wind: Light and variable Sea-level pressure: 30.32 ins. Hg, rising, then falling Visibility: 70 miles BHO SA 1455 CLR 70 268/62/46/E0601/032/ FEW DSNT CU ENE-SSE WND L/V/ 8/100 50001 1 P.M. Weather: Clear Temperature: 68F; Dew Point: 42F; Wind: estimated SSW at 2 kts, Wind Speed: Light Sea-level pressure: 30.29 ins. Hg, falling, then more quickly Visibility: 70 miles 6-hr Max. temp: 69F 6-hr Min. temp: 50F BHO SA 1755 CLR 70 256/68/42/E2002/029/ SKC WND LGT/ 58012 10069 20050 SUMMARY FOR WEDNESDAY, OCTOBER 5, 2016 TEMPERATURE (DEGREES F) MAX.....61 NORMAL.....64 MIN.....44 NORMAL.....47 MEAN....53 NORMAL.....56 DEPARTURE FROM 30-YEAR NORMAL........................-3 TOTAL DEPARTURE FOR THE MONTH........................-1 [-0.4 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY...............0 DEPARTURE...........0 TOTAL COOLING UNITS FOR THE MONTH...............0 DEPARTURE..........-2 TOTAL COOLING UNITS FOR THE SEASON............894 DEPARTURE........+295 TOTAL COOLING UNITS LAST SEASON TO DATE.......810 DIFFERENCE........+84 HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............12 DEPARTURE..........+2 TOTAL HEATING UNITS FOR THE MONTH..............48 DEPARTURE..........+2 TOTAL HEATING UNITS FOR THE SEASON............123 DEPARTURE.........-65 TOTAL HEATING UNITS LAST SEASON TO DATE.......103 DIFFERENCE........+10 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................22 NE AT 8:27 A.M. ASOS........................22 NE AT 8:28 A.M. DAVIS.......................20 NE AT 8:27 A.M. RMY 21 FASTEST MILE FOR YESTERDAY.....................12 NE AT 8:29 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................14 ENE AT 12:10 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................13 NNE AT 8:28 A.M. AVERAGE WIND SPEED AND DIRECTION..............7.5 N ASOS.......................7.7 DAVIS......................6.8 NNE [030 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..........1.41 DEPARTURE......+0.67 ASOS..............1.43 TOTAL PRECIPITATION FOR THE YEAR..........28.73 DEPARTURE.....-11.09 ASOS.............29.07 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/+7/0.16/152/21 32 NE AERO M RMY 32 9/24 66/48/57/-3/0.03/643/89 24 NW AERO M RMY 25 9/25 65/44/55/-5/0.00/698/97 31 NW AERO M RMY 32 9/26 68/43/56/-3/0.00/624/87 25 S AERO M RMY 25 9/27 69/57/63/+4/0.31/021/03 23 S AERO M RMY N/A 9/28 59/52/56/-2/0.08/000/00 33 NNE AERO M RMY N/A 9/29 55/52/54/-4/0.00/028/04 33 NE AERO M RMY N/A 9/30 58/53/56/-2/0.30/000/00 32 ENE AERO M RMY 32 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 PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 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 10/1 57/52/55/-2/1.22/000/00 33 NNE AERO M RMY 34 10/2 55/52/54/-3/0.19/.../.. 23 N AERO M RMY N/A 10/3 69/53/61/+5/0.00/.../.. 21 ENE AERO M RMY 20 10/4 61/47/54/-2/T/.../.. 26 NE AERO M RMY 27 10/5 61/44/53/-3/0.00/.../.. 22 NE AERO M RMY 21 10/6 Low temp since midnight is 46F; normal low is now 47F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR OCTOBER 6 HIGH 83F IN 1990, 2007 LOW 26F IN 1965 PRECIP 3.78 INCHES IN 1962 PEAK GUST 60e MPH S IN 1942 RECORDS FOR OCTOBER 7 HIGH 88F IN 1963 (RECORD FOR MONTH) LOW 30F IN 1904,1986 PRECIP 1.75 INCHES IN 1972 PEAK GUST 54 W IN 2009 TODAY'S REPORT PREPARED BY: Cecilia Borries-Strigle