BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, NOVEMBER 18, 2012 ALL TIMES ARE IN EASTERN STANDARD TIME VERY STRONG HIGH PRESSURE AND VERY LIGHT WINDS RESULTED IN STRONG RADIATIONAL COOLING LAST NIGHT BAROMETER RISES PAST 30.70 INCHES Clear sky and calm winds allowed for strong radiational cooling with overnight low temperatures dropping to a frosty 20 degrees at nearby Norwood Airport and 22 degrees at Taunton Airport. We had some frost here at the summit but the low temperature was only 30F. A thin undercast of fog was visible below the summit below the inversion. The barometric pressure corrected to sea level has risen over 30.70 inches this morning for our highest readings since March 2011 when the pressure rose to 30.78 inches. Today's observations: 7 A.M. Weather: Clear, lone moderate cumulus along shore ENE, altocumulus/few altocumulus lenticularis mostly distant N-E-SE and W, thin fog below inversion (thin undercast), frost Temperature: 30F; Dew Point: 27F; Wind: N at 9 kts Sea-level pressure: 30.71 ins. Hg, rising then more rapidly Visibility: 9 miles, thin fog 6-hour min. temp: 30F BHO SA 1155 CLR 9 398/30/27/3609/071/ LONE MDT CU ALGSHR ENE FEW AC/ACSL DSNT N-E-SE AND W THN F UNDRCST CDN BLO INVSN ESTMTD TOP 6 HND OVR CTY N FROST/ 8/240 53018 10035 20030 10 A.M. Weather: Clear, lone moderate cumulus along shore ENE, few stratocumulus along shore NE and distant ESE-SSE, few cirrus distant SE-SW and NW-N, hazy all quadrants Temperature: 41F; Dew Point: 32F; Wind: NNE at 7 kts, Wind: Direction variable N-ENE Sea-level pressure: 30.71 ins. Hg, rising slightly Visibility: 12 miles, hazy BHO SA 1455 CLR 12 399/41/32/0307/071/ LONE MDT CU ALGSHR ENE AND FEW SC NE AND ESE-SSE CI DSNT NW-N HAZY ALQDS WND 35V06/ 8/801 51001 WEATHER SUMMARY FOR SATURDAY, NOVEMBER 17 TEMPERATURE (DEGREES F) MAX.....47 NORMAL.....50 MIN.....32 NORMAL.....33 MEAN....40 NORMAL.....41 DEPARTURE FROM 30-YEAR NORMAL.....................-1 TOTAL DEPARTURE FOR THE MONTH....................-24 [-1.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............25 DEPARTURE........+1 TOTAL HEATING UNITS FOR THE MONTH...........383 DEPARTURE.......+24 TOTAL HEATING UNITS FOR THE SEASON..........791 DEPARTURE......-131 TOTAL HEATING UNITS LAST SEASON TO DATE.....680 DIFFERENCE.....+111 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..............20 N AT 4:53 A.M. * AERO...................19 N AT 3:43 A.M. ASOS...................20 N AT 3:43 A.M. DAVIS..................19 NNW AT 2:55 A.M. THE FASTEST MILE FOR YESTERDAY............15 NNW AT 2:56 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE.............15 N AT 3:08 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE............15 NNW AT 2:56 A.M. AVERAGE WIND SPEED AND DIRECTION.........8.2 N ASOS..................8.2 DAVIS.................7.9 NNE [020 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..........1.49 DEPARTURE..........-1.18 ASOS..............1.52 TOTAL PRECIPITATION FOR THE YEAR..........34.69 DEPARTURE.........-11.75 ASOS.............34.70 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE..........-0.1 TOTAL SNOWFALL FOR THE MONTH...............4.0 DEPARTURE..........+3.3 TOTAL SNOWFALL FOR THE SEASON..............4.0 DEPARTURE..........+3.0 PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 2012 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust RMY: RMY = R.M. Young wind gust recording system added 8/9/2011 TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 11/1 56/42/49/+3/0.00/371/60 28 SW AERO 28 MPH SW RMY 27 11/2 51/41/46/0/0.02/000/00 24 WNW AERO 22 MPH WNW RMY 22 11/3 52/37/45/-1/0.00/319/52 29 NW AERO N/A RMY 28 11/4 52/34/43/-2/0.00/587/96 27 NW AERO 25 MPH NW RMY 26 * 11/5 45/28/37/-8/0.00/292/48 25 NW AERO 25 MPH NW RMY 25 11/6 40/25/33/-12/0.00/600/99 22 ENE AERO 20 MPH ENE RMY N/A 11/7 42/29/36/-9/0.78/3.5/000/00 48 NNE AERO 52 MPH NNE RMY 51 11/8 36/29/33/-11/0.26/0.5/000/00 43 N AERO 50 MPH N RMY 44 11/9 51/34/43/-1/0.00/0.0/569/95 33 NW AERO 35 MPH NW RMY 32 11/10 53/36/45/+1/0.00/0.0/561/94 25 W AERO 23 MPH W RMY 23 11/11 62/40/51/+8/0.00/0.0/357/60 28 SSW AERO 27 MPH SSW RMY 28 11/12 66/50/58/+15/0.00/0.0/385/65 33 SSW AERO 33 MPH S RMY N/A 11/13 63/37/50/+7/0.43/0.0/000/00 45 S AERO 45 MPH S RMY N/A 11/14 44/33/39/-3/0.00/0.0/559/95 27 NNE AERO 23 MPH N RMY 24 11/15 39/32/36/-6/0.00/0.0/.../.. 23 N AERO 21 MPH N RMY 25 11/16 45/31/38/-4/0.00/0.0/.../.. 18 NNW AERO 17 MPH NNW RMY 19 11/17 47/32/40/-1/0/00/0/0/.../.. 20 N AERO 20 MPH N RMY N/A * Sunshine minutes for 4th corrected from 570 to 587 11/18 morning low temp: 30F; the normal low is now 33F DAILY RECORDS FOR NOVEMBER 2012 11/7 - NEW DAILY RECORD MAXIMUM SNOWFALL OF 3.5 INCHES; surpasses the previous record of 1.0 inch in 1967 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR NOVEMBER 18 HIGH 72 IN 1963 LOW 10 IN 1936 PRECIP 1.80 INS IN 1929 SNOWFALL 6.3 INS IN 1980 PEAK GUST 60 SW IN 1987 RECORDS FOR NOVEMBER 19 HIGH 72 IN 1941 LOW 10 IN 1936 PRECIP 1.92 INCHES IN 1926 SNOWFALL 11.0 INS IN 1986 PEAK GUST 59e E IN 1945 TODAY'S REPORT PREPARED BY: Robert Skilling/Peter Volpe