BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, SEPTEMBER 19, 2015 ALL TIMES ARE IN EASTERN STANDARD TIME 64 TIES THE RECORD FOR HIGHEST MINIMUM TEMPERATURE FOR SEPTEMBER 18TH. **BLUE HILL OBSERVATORY NEEDS YOUR SUPPORT FOR A NEW AEROVANE ANEMOMETER- STILL MORE THAN $5,000 AWAY PLEASE SUPPORT OUR KICKSTARTER FUNDRAISER BY VISITING:** www.kickstarter.com/projects/1451380431/fund-the-future-of-climate-science-at-blue-hill-ob Dense but shallow fog settled over the hilltop this morning and that kept morning temperatures low, but the sun burned the fog off quickly and temperature began to climb by the 10 o'clock observation. The overnight low reached 64 degrees which ties the daily record high minimum of 64F, set back in 1992. By the 1:00 PM EST observation temperatures had reached a maximum of 79F so far as winds began to pick up out of the south, gusting as high as 20 MPH, and clouds gave way to additional sunshine. Today's Observations: 7 A.M. Weather: Fog with thin spots overhead Temperature: 62F; Dew Point: 62F; Wind: estimated SSE at 6 kts, Wind Speed: Light Sea-level pressure: 29.99 ins. Hg, falling Visibility: 1/16 miles, fog 6-hr Max temp: 63F 6-hr Min temp: 61F 24-hr precip: 0.00 in. BHO SA 1155 W1 X 1/16F 156/62/62/E1506/999/ THN SPTS IN FOG OVHD WND LGT/ 8//// 58004 10063 20061 10 A.M. Weather: Scattered Cumulus, Scattered Cirrostratus Temperature: 72F; Dew Point 63F; Wind: SSW at 11 kts, Sea-level pressure: 30.00 ins. Hg, rising, then falling but still higher Visibility: 20 miles,except 15 NNE hazy BHO SA 1455 16 SCT 250 SCT 20 159/72/63/2111/000/ HAZY VSBY 15 NNE 8/102 50003 1 P.M. Weather: Scattered Cumulus, Thin scattered Cirrostratus Temperature: 79F; Dew Point: 62F; Wind: S at 13 kts, gusts to 20 Sea-level pressure: 29.94 ins. Hg, falling, then more quickly Visibility: 60 miles, light distant haze 6-hr Max: 79F 6-hr Min: 63F BHO SA 1755 35 SCT 250 -SCT 60 139/79/62/1713G20/994/ FEW MDT CU E-ESE VSBY 40 ENE-E LGT DSNT HZ/ 8/102 58017 10079 20063 SUMMARY FOR FRIDAY, SEPTEMBER 18, 2015 TEMPERATURE (DEGREES F) MAX.....86 NORMAL.....71 MIN.....64 NORMAL.....54 MEAN....75 NORMAL.....62 DEPARTURE FROM 30-YEAR NORMAL.......................+13 TOTAL DEPARTURE FOR THE MONTH......................+114 [+5.8 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY..............10 DEPARTURE..........+8 TOTAL COOLING UNITS FOR THE MONTH.............125 DEPARTURE.........+77 TOTAL COOLING UNITS FOR THE SEASON............791 DEPARTURE........+206 TOTAL COOLING UNITS LAST SEASON TO DATE.......565 DIFFERENCE.......+226 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................21 SSW AT 5:33 P.M. ASOS........................23 S AT 5:34 P.M. DAVIS.......................19 SSW AT 5:58 P.M. RMY 21 FASTEST MILE FOR YESTERDAY.................... 15 SSW AT 5:32 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................16 S AT 5:35 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................15 SSW AT 5:35 P.M. AVERAGE WIND SPEED AND DIRECTION...............9.3 SSW ASOS........................9.4 DAVIS.......................8.4 SW [234 DEG] 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...........1.35 DEPARTURE.....-0.95 ASOS...............1.33 TOTAL PRECIPITATION FOR THE YEAR...........31.60 DEPARTURE.....-5.71 ASOS................N/A *** *** ASOS annual total not available due to erroneous readings PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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 9/1 81/65/73/+5/0.00/766/97 20 SSW RMY 20 9/2 89/64/77/+9/0.00/732/93 20 SW RMY 21 9/3 85/66/76/+9/T/612/78 17 E RMY N/A TSTM 9/4 72/58/65/0/0.00/297/38 31 ENE RMY N/A 9/5 77/55/66/-1/0.00/748/96 14 SW RMY 18 9/6 87/57/72/+5/0.00/753/97 21 SSW RMY 22 9/7 92/63/78/+12/0.00/727/94 23 WSW RMY 24 9/8 97/70/84/+18/0.00/693/90 22 WSW RMY 24 9/9 92/70/81/+15/0.00/683/89 30 SSW RMY 33 9/10 73/62/68/+3/..../000/00 29 NE RMY N/A 9/11 70/59/65/0/..../084/11 33 NE RMY N/A 9/12 75/58/67/2/..../.../.. 18 SSE RMY 25 9/13 66/60/63/-1/..../000/00 25 E RMY N/A 9/14 70/53/62/-2/0.00/.../.. 33 W RMY 35 9/15 82/56/69/+5/0.00/.../.. 23 W RMY N/A 9/16 84/62/73/+10/0.00/.../.. 17 NW RMY N/A 9/17 87/64/76/+13/0.00/.../.. 17 SW RMY 16 9/18 86/64/75/+13/0.00/.../.. 21 SSW RMY 21 9/19 low since midnight is 64F; normal low is now 54F DAILY RECORDS FOR SEPTEMBER 2015 **9/7 DAILY RECORD MAXIMUM TEMPERATURE OF 92F TIES PREVIOUS RECORD SET IN 2007** **9/8 DAILY RECORD MAXIMUM TEMPERATURE OF 97F BREAKS PREVIOUS RECORD OF 93F SET IN 2007** **9/8 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F BREAKS PREVIOUS RECORD OF 69F SET IN 1999** **9/9 DAILY RECORD MAXIMUM TEMPERATURE OF 92F BREAKS PREVIOUS RECORD OF 91F SET IN 2002** **9/9 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 70F BREAKS PREVIOUS RECORD OF 69F SET IN 1999** **9/17 DAILY RECORD MAXIMUM TEMPERATUER OF 87F BREAKS PREVIOUS RECORD OF 86F SET IN 1915, 1941, AND 1991** **9/18 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 64F TIES PREVIOUS RECORD SET IN 1992** DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR SEPTEMBER 19 HIGH 87F IN 1906,1983 LOW 37F IN 1929 PRECIP 3.69 INCHES IN 1936 PEAK GUST 55 MPH S IN 2012 RECORDS FOR SEPTEMBER 20 HIGH 90 IN 1983 LOW 34 IN 1979 PRECIP 4.57 INS IN 1899 PEAK GUST 44 MPH NE IN 1972 TODAY'S REPORT PREPARED BY: Robert Millette