BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, DECEMBER 5, 2015 ALL TIMES ARE IN EASTERN STANDARD TIME TEMPERATURE WARMS TO NEAR 50 AFTER A COOL START THIS MORNING...COMPLETELY CLOUDLESS SKY TODAY WITH HAZE LIMITING VISIBILITY...NOVEMBER MAXIMUM SEA-LEVEL PRESSURE TIES RECORD FOR MONTH... A low-level inversion this morning held the minimum temperature to 33F on the summit today, while the low temperature was 24F at nearby Norwood Airport. As temperatures have climbed through the 40s during the day, haze trapped below the inversion has reduced visibility, especially to the west through northeast. The sky has been completely free of clouds today with generally light winds. The maximum sea-level pressure for November of 30.88 inches, which occurred late on the 25th, ties the highest pressure ever measured in the month that was previously set on November 28, 1932. BHO Warmest Novembers, deg F (1885-2015): 1) 47.9 in 2011 2) 47.4 in 1975 3) 47.1 in 2006 4) 46.4 in 1948 46.4 in 1979 46.4 in 2009 7) 46.1 in 2015 8) 46.0 in 2001 9) 45.7 in 1953 45.7 in 1999 BHO Highest November Sea-Level Pressure, inches (1885-2015): 1) 30.88 in 1932 30.88 in 2015 3) 30.86 in 1887 4) 30.83 in 1896 5) 30.82 in 1891 6) 30.80 in 1996 7) 30.79 in 2013 8) 30.77 in 1914 PRELIMINARY STATS FOR NOVEMBER 2015 TEMPERATURE, Deg. F Avg. Max. 54.3 [+4.3] Avg. Min. 38.6 [+5.1] Mean 46.5 [+4.8] Corrected mean: 46.1 Max. for month: 72 on 5th Min. for month: 23 on 24th COOLING DEGREE DAYS Total cooling units: 1 [+1] Total for the season: 811 [+209] Total for last season: 595 HEATING DEGREE DAYS Total heating units: 548 [-150] Total for the season: 1002 [-259] Total for last season: 1159 PRECIPITATION, Inches Total: 2.59 [-2.18] Greatest in 24 hrs: 1.18 from 20th Snowfall: Trace [-2.3] Seasonal: Trace [-2.6] WIND, mph Avg. uncorrected wind speed: 12.4 Avg. corrected wind speed: 12.7 Prevailing wind direction: W @ 13% Peak gust and direction: 43 SSE on the 20th SUNSHINE: Campbell-Stokes card minutes: 9222/17010 or 54% Astronomical total minutes: 9562/17644 or 54% Today's Observations: 7 A.M. Weather: Clear, no clouds, hazy Temperature: 35F; Dew Point: 32F; Wind: W at 12 kts Sea-level pressure: 30.62 ins. Hg, rising Visibility: 40 miles 6-hr Max temp: 35F 6-hr Min temp: 33F 24-hr precip: 0.00 BHO SA 1155 CLR 40 369/35/32/2812/062/ SKC HAZY/ 52015 10035 20033 10 A.M. Weather: Clear, no clouds, hazy Temperature: 43F; Dew Point: 35F; Wind: W at 6 kts, Wind Speed: Light Sea-level pressure: 30.66 ins. Hg, rising, then more slowly Visibility: 35 miles BHO SA 1455 CLR 35 381/43/35/2606/066/ SKC HAZY WND LGT/ 51012 1 P.M. Weather: Clear, no clouds, hazy, visibility lower NW-NE Temperature: 49F; Dew Point: 33F; Wind: W at 5 kts, Wind Speed: Light Sea-level pressure: 30.62 ins. Hg, falling, then more slowly Visibility: 45 miles 6-hr max. temp: 49F 6-hr min. temp: 35F BHO SA 1755 CLR 45 370/49/33/2705/062/ SKC HAZY VSBY LWR NW-NE WND LGT/ 56011 10049 20035 SUMMARY FOR FRIDAY, DECEMBER 4, 2015 TEMPERATURE (DEGREES F) MAX.....47 NORMAL.....43 MIN.....32 NORMAL.....28 MEAN....40 NORMAL.....35 DEPARTURE FROM 30-YEAR NORMAL......................+5 TOTAL DEPARTURE FOR THE MONTH.....................+22 [+5.3 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............25 DEPARTURE..........-5 TOTAL HEATING UNITS FOR THE MONTH..............94 DEPARTURE.........-22 TOTAL HEATING UNITS FOR THE SEASON...........1096 DEPARTURE........-282 TOTAL HEATING UNITS LAST SEASON TO DATE......1259 DIFFERENCE.......-163 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................32 NW AT 4:29 P.M. ASOS........................31 NW AT 4:29 P.M. DAVIS.......................28 NW AT 4:28 P.M. RMY 32 FASTEST MILE FOR YESTERDAY.....................22 NW AT 4:29 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE..................21 WNW AT 4:30 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................19 WNW AT 4:30 P.M. AVERAGE WIND SPEED AND DIRECTION.............12.3 WNW ASOS......................11.4 DAVIS.....................10.3 WNW [302 Deg.] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.00 DEPARTURE......-0.16 ASOS...............0.00 TOTAL PRECIPITATION FOR THE MONTH...........0.37 DEPARTURE......-0.28 ASOS...............0.36 TOTAL PRECIPITATION FOR THE YEAR...........39.79 DEPARTURE......-9.40 ASOS................N/A *** *** ASOS annual total not available due to erroneous readings SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE......-0.3 TOTAL SNOWFALL FOR THE MONTH................0.0 DEPARTURE......-1.1 TOTAL SNOWFALL FOR THE SEASON.............TRACE DEPARTURE......-3.7 PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER & DECEMBER 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 11/1 59/45/52/+6/T/006/01 30 SSW RMY 31 11/2 62/47/55/+9/0.00/476/77 24 W RMY N/A 11/3 71/44/58/+12/0.00/616/100 25 W RMY 25 11/4 66/49/58/+13/0.00/601/98 22 SSW RMY N/A 11/5 72/51/62/+17/0.00/281/46 31 SW RMY 36 11/6 71/60/66/+21/0.00/109/18 35 SSW RMY 38 11/7 64/46/55/+10/0.00/029/04 33 WNW RMY 35 11/8 54/39/47/+3/0.00/591/98 26 NW RMY 30 11/9 59/38/49/+5/0.00/577/96 20 W RMY 21 11/10 53/45/49/+5/0.11/000/00 28 NE RMY N/A 11/11 48/43/46/+3/0.60/000/00 41 NE RMY N/A 11/12 55/42/49/+6/0.07/000/00 28 S RMY 30 11/13 57/41/49/+6/0.02/385/65 40 WSW RMY 47 11/14 45/31/38/-4/0.00/425/72 40 NW RMY 47 11/15 51/31/41/-1/0.00/241/41 25 W RMY 27 11/16 59/36/48/+6/0.00/416/71 25 NNW RMY 29 11/17 45/28/37/-4/0.00/572/98 18 NNE RMY N/A 11/18 50/35/43/+2/0.00/575/99 17 SSE RMY N/A 11/19 55/38/47/+6/T/000/00 29 SSE RMY N/A 11/20 58/41/50/+10/1.18/416/72 43 SSE RMY N/A 11/21 46/35/41/+1/0.00/380/66 20 ENE RMY 21 11/22 45/35/40/+0/0.40/000/00 26 NW RMY 28 11/23 40/25/33/-6/0.02/543/95 24 NW RMY 29 11/24 42/23/33/-6/0.00/564/99 20 WSW RMY 19 11/25 46/31/39/+0/0.00/568/100 18 SSE RMY N/A 11/26 58/37/48/+10/0.00/386/68 33 S RMY 35 11/27 63/48/54/+18/0.00/249/44 35 SW RMY 38 11/28 55/38/47/+9/0.19/000/00 23 SW RMY N/A 11/29 42/28/35/-2/0.00/410/73 17 NNW RMY 21 11/30 37/27/32/-5/T/T/151/27 17 S RMY 18 12/1 42/30/36/-1/..../0.0/000/00 19 NNE RMY 19 12/2 53/37/45/+9/..../0.0/000/00 25 SSE RMY 25 12/3 53/37/45/+9/..../0.0/.../.. 43 WNW RMY 42 12/4 47/32/40/+5/0.00/0.0/.../.. 32 NW RMY 32 12/5 low since midnight is 33F; normal low is now 27F DAILY RECORDS FOR NOVEMBER AND DECEMBER 2015 **11/6 DAILY RECORD MAXIMUM TEMPERATURE OF 71F TIES PREVIOUS RECORD OF 71F SET IN 1959 **11/6 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 60F BREAKS PREVIOUS RECORD OF 58F SET IN 1938 **11/6 DAILY RECORD HIGH MINIMUM TEMPERATURE OF 60F TIES PREVIOUS MONTHLY RECORD OF 60F SET ON 11/8/1996 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 5 HIGH 65 IN 2001 LOW -1 IN 1926 PRECIP 2.86 INS. IN 1993 SNOWFALL 7.0 INS. IN 1926, 1981 PEAK GUST 67 MPH WNW IN 1961, S IN 1973 RECORDS FOR DECEMBER 6 HIGH 70 IN 2001 LOW 5 IN 1901,1935 PRECIP 2.78 INS. IN 2003 SNOWFALL 17.0 INS. IN 2003 PEAK GUST 74 MPH NW IN 1981 TODAY'S REPORT PREPARED BY: Mike Iacono / Rob Millette