BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, SEPTEMBER 6, 2015 ALL TIMES ARE IN EASTERN STANDARD TIME SPECTACULAR LATE SUMMER WEATHER TODAY...BRILLIANT SUNSHINE WITH SEASONABLE TEMPERATURES AND LOW HUMIDITY...AUGUST SUNSHINE WAS THE SECOND HIGHEST ON RECORD... While dew points continue to remain low after the cold front that Passed through the region a few days ago, temperatures have returned To being above average with a high temperature of 87 degrees by the 1 O’clock observation. This is more than 10 degrees above normal. With the dry air, the visibility has been excellent today in the 60-70 mile range. Only a few thin cirrus to the West have interrupted an almost completely clear sky. BHO Warmest Augusts, deg F (1885-2015) 1) 72.6 in 2012 2) 72.5 in 1988 3) 72.4 in 2015 4) 72.3 in 2005 5) 72.1 in 2002 BHO Warmest August Average Maximum Temperature, deg F (1885-2015) 1) 83.2 in 2005 2) 83.1 in 1949 3) 82.6 in 2015 4) 82.5 in 1988 82.5 in 2002 82.5 in 2012 BHO Warmest August Average Minimum Temperature, deg F (1885-2015) 1) 64.9 in 2001 2) 64.6 in 2012 3) 64.4 in 2005 64.4 in 2015 5) 64.3 in 2003 BHO Slowest August Wind Speed, mph (1885-2015) 1) 9.5 in 1996 9.5 in 2008 3) 10.0 in 1899 10.0 in 2009 10.0 in 2012 10.0 in 2015 BHO Sunniest Augusts, hours (1886-2015) 1) 303.7 in 1971 (74%) 2) 303.2 in 2015 (73%) 3) 303.0 in 1969 (73%) 4) 298.1 in 1932 (72%) 5) 296.7 in 1970 (72%) PRELIMINARY STATS FOR AUGUST 2015 TEMPERATURE, Deg. F Avg. Max. 82.6 [+3.4] Avg. Min. 64.4 [+2.6] Mean 73.5 [+3.0] Corrected mean: 72.4 Max. for month: 92 on 18th Min. for month: 58 on 8th, 10th, 28th HEATING DEGREE DAYS (JUL-JUN) Total heating units: 0 [-16] Total for the season: 1 [-24] Total for last season: 2 COOLING DEGREE DAYS (JAN-DEC) Total cooling units: 272 [+86] Total for the season: 666 [+129] Total for last season: 479 PRECIPITATION, Inches Total: 2.90 [-1.13] Greatest in 24 hrs: 1.24, 15th-16th WIND, mph Avg. uncorrected wind speed: 9.3 Avg. corrected wind speed: 10.0 Prevailing wind direction: WNW @ 15% Peak gust and direction: 45 W on the 4th [TSTM GUST] SUNSHINE: (corrected) Campbell-Stokes card minutes: 18192 mins. of possible 24780 or 73% Astronomical total minutes: 18916 mins. of possible 25773 or 73% Long-term average for August is 58% Today's Observations: 7 A.M. Weather: Clear, cloudless sky, light distant haze Temperature: 63F; Dew Point: 56F; Wind: W at 8 kts, Sea-level pressure: 30.22 ins. Hg, steady then rising Visibility: 60 miles 6-hr Max temp: 63F 6-hr Min temp: 59F 24-hr precip: 0.00 BHO SA 1155 CLR 65 236/63/56/2708/022/ SKC LGT DSNT HZ/ 8/000 53004 10063 20059 10 A.M. Weather: Clear, few altocumulus distant SW and ESE Temperature: 78F; Dew Point 53F; Wind: VRB at 4 kts, Wind: Light and Variable Sea-level pressure: 30.21 ins. Hg, rising then falling Visibility: 75 miles BHO SA 1455 CLR 75 233/78/53/VRB04/021/ FEW AC DSNT SW AND ESE WND LGT/ 8/040 58003 1 P.M. Weather: Clear, Few cirrus distant W-NNW Temperature: 87F; Dew Point: 54F; Wind: W at 5 kts Wing: Light Sea-level pressure: 30.18 ins. Hg, falling then more slowly Visibility: 60 miles BHO SA 1755 CLR 60 222/87/54/2605/018/ FEW CI DSNT W-NNW LGT DSNT HZ WND LGT/ 8/002 56011 10087 20063 SUMMARY FOR SATURDAY, SEPTEMBER 5, 2015 TEMPERATURE (DEGREES F) MAX.....77 NORMAL.....75 MIN.....55 NORMAL.....58 MEAN....66 NORMAL.....67 DEPARTURE FROM 30-YEAR NORMAL........................-1 TOTAL DEPARTURE FOR THE MONTH.......................+20 [+5.1 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY...............1 DEPARTURE..........-2 TOTAL COOLING UNITS FOR THE MONTH..............32 DEPARTURE.........+14 TOTAL COOLING UNITS FOR THE SEASON............698 DEPARTURE........+143 TOTAL COOLING UNITS LAST SEASON TO DATE.......541 DIFFERENCE.......+157 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................16 SW AT 10:26 P.M. ASOS........................17 SSW AT 10:39 P.M. DAVIS.......................17 WSW AT 11:23 A.M. RMY 18 FASTEST MILE FOR YESTERDAY.....................24 NE AT 4:59 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..................14 SW AT 11:18 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................13 SW AT 11:31 P.M. AVERAGE WIND SPEED AND DIRECTION..............7.8 NNE ASOS.......................8.2 DAVIS......................7.1 ENE [77 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.00 DEPARTURE.....-0.12 ASOS...............0.00 TOTAL PRECIPITATION FOR THE MONTH..........Trace DEPARTURE.....-0.58 ASOS...............0.00 TOTAL PRECIPITATION FOR THE YEAR...........30.26 DEPARTURE.....-5.34 ASOS................N/A *** *** ASOS annual total not available due to erroneous readings PRELIMINARY CLIMATE SUMMARY FOR AUGUST & 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 8/1 88/68/78/+6/0.06/729/84 28 WNW RMY N/A 8/2 86/62/74/+2/0.00/865/100 24 SW RMY N/A 8/3 89/68/79/+7/0.00/690/80 31 S RMY N/A 8/4 86/66/76/+4/0.31/422/49 45 W RMY 50 TSTM 8/5 84/64/74/+2/0.00/765/89 28 WNW RMY 27 8/6 80/59/70/-2/0.00/685/80 22 W RMY 21 8/7 78/61/70/-2/0.00/845/99 20 ESE RMY 18 8/8 77/58/68/-4/0.00/741/87 18 E RMY N/A 8/9 72/59/66/-6/T/458/54 27 NNE RMY 26 8/10 84/58/71/0/0.00/830/98 28 S RMY N/A 8/11 70/63/67/-4/0.52/000/00 32 SSE RMY 35 8/12 83/65/74/+3/0.00/766/91 22 W RMY 20 8/13 83/62/73/+2/0.00/832/99 18 WNW RMY 18 8/14 86/63/75/+4/0.00/837/100 21 S RMY 23 8/15 91/66/79/+8/1.24/534/64 38 W RMY 41 TSTM 8/16 87/65/76/+5/T/774/93 16 W RMY N/A TSTM 8/17 90/70/80/+9/0.00/805/97 17 W RMY 18 8/18 92/70/81/+10/0.27/546/66 31 W RMY 32 TSTM 8/19 87/69/78/+8/0.00/775/94 23 S RMY 24 8/20 85/70/78/+8/0.00/723/88 22 ESE RMY 22 8/21 82/69/76/+6/0.31/328/40 21 S RMY 23 8/22 73/66/70/0/T/98/12 18 ENE RMY 16 8/23 70/66/68/-2/0.18/000/00 20 ENE RMY 18 8/24 78/67/73/+3/0.01/122/15 18 SSW RMY 19 8/25 85/68/77/+8/0.00/526/65 22 S RMY 22 8/26 82/64/73/+4/0.00/629/78 21 NW RMY 22 8/27 79/59/69/0/0.00/779/97 22 W RMY 23 8/28 80/58/69/0/0.00/753/94 15 NW RMY 15 8/29 81/60/71/+2/0.00/766/96 21 WSW RMY 21 8/30 86/65/76/+8/0.00/588/74 23 W RMY 23 8/31 87/68/78/+10/0.00/705/89 26 W RMY 28 9/1 81/65/73/+5/0.00/.../.. 20 SSW RMY 20 9/2 89/64/77/+9/0.00/.../.. 20 SW RMY 21 9/3 85/66/76/+9/trace/.../.. 17 E RMY N/A TSTM 9/4 72/58/65/0/0.00/.../.. 31 ENE RMY N/A 9/5 77/55/66/-1/0.00/.../.. 14 SW RMY 18 9/6 low since midnight is 58F; normal low is now 58F DAILY RECORDS FOR AUGUST 2015 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR SEPTEMBER 6 HIGH 92F IN 1900 LOW 39F IN 1888 PRECIP 3.19 INCHES IN 1890 PEAK GUST 78e MPH SE IN 1979 (TROPICAL STORM DAVID) RECORDS FOR SEPTEMBER 7 HIGH 92F IN 2007 LOW 40F IN 1888 PRECIP 2.95 INCHES IN 1891 PEAK GUST 58e MPH W IN 1941 TODAY'S REPORT PREPARED BY: Robert Millette