BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, DECEMBER 18, 2005 ALL TIMES ARE IN EASTERN STANDARD TIME Today's observations: 7 A.M. Weather: Thin overcast cirrus Temperature: 24F, Dew point: 18F, Wind: W at 11 kt Sea-level pressure: 30.46 inches Hg, rising Visibility: 15 miles BHO SA 1155 -OVC 200 15 314/24/18/2611/046/ FEW BINOVC ALQDS DISC OF MOON VSBL/ 8/001 4/001 58004 10026 20024 10 A.M. Weather: Overcast cirrus Temperature: 26F, Dew point: 19F, Wind: WSW at 10 kt Sea-level pressure: 30.46 inches Hg, rising Visibility: 25 miles BHO SA 1455 OVC 200 25 314/26/19/2410/046/ FEW BINOVC NW-N/ 8/001 55000 WEATHER SUMMARY FOR SATURDAY, DECEMBER 17 TEMPERATURE (DEGREES F) MAX.....37 NORMAL.....38 ASOS.....36 AT 2:46 P.M. MIN.....26 NORMAL.....23 ASOS.....26 AT MIDNIGHT P.M. MEAN....32 NORMAL.....31 DEPARTURE FROM 30-YEAR NORMAL.......+1 TOTAL DEPARTURE FOR THE MONTH......-96 (-5.4 DEGREES/DAY) HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY..........33 DEPARTURE.....-1 TOTAL HEATING UNITS FOR THE MONTH.........637 DEPARTURE...+103 TOTAL HEATING UNITS FOR THE SEASON.......1702 DEPARTURE...-124 TOTAL HEATING UNITS LAST SEASON TO DATE..1712 DIFFERENCE...-10 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.........25 W AT 2:13 P.M. AEROVANE..........29 W AT 12:18 P.M. ASOS..............24 W AT 2:14 P.M. DAVIS.............27 W FASTEST MILE FOR YESTERDAY...........23 W AT 12:14 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE........21 WSW AT 12:18 P.M. AVERAGE WIND SPEED AND DIRECTION...13.8 W ASOS............13.4 PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE....+0.00 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........2.35 DEPARTURE....-0.14 ASOS..............2.27 TOTAL PRECIPITATION FOR THE YEAR..........64.62 DEPARTURE...+15.76 ASOS.............63.42* *EXCLUDES 3.19 INCHES OF ERRONEOUS PRECIPITATION RECORDED FROM 1/23-1/28. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE.....-0.4 TOTAL SNOWFALL FOR THE MONTH...............13.1 DEPARTURE.....+8.0 TOTAL SNOWFALL FOR THE SEASON..............15.2 DEPARTURE.....+7.2 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2005......CALENDAR DAY DATA DATA REPORTED: DATE MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available 12/1 43/35/39/+3/0/0/212/38 29 MPH N 12/2 41/31/36/0/0/0/217/39 46 MPH WSW Aero 51 MPH WSW 12/3 33/26/30/-5/0/0/534/96 46 MPH W Aero 50 MPH W 12/4 28/22/25/-10/0.24/2.2/000/00 22 MPH W 12/5 32/21/27/-8/0/0/061/11 23 MPH WSW 12/6 33/23/28/-6/T/0.1/160/29 31 MPH W Aero 36 MPH W 12/7 28/16/22/-12/T/T/479/87 44 MPH WNW Aero 50 MPH WNW 12/8 31/14/23/-10/0/0/545/99 25 MPH NW 12/9 32/22/27/-6/1.23/10.8/000/00 53 MPH NW Aero 63 MPH NW TSTM/SLEET/GLAZE 12/10 34/21/28/-5/0/0/367/67 30 MPH S 12/11 40/27/34/+2/0/0/493/90 27 MPH SSW 12/12 38/21/30/-2/0/0/241/44 25 MPH W 12/13 21/09/15/-17/T/T/361/66 32 MPH WNW Aero 35 MPH WNW 12/14 23/04/14/-17/0/0/513/94 24 MPH NW 12/15 32/07/20/-11/0/0/.../.. 21 MPH E 12/16 48/27/38/+7/0.88/0/000/00 55 MPH ESE Aero 61 MPH ESE SLEET/GLAZE 12/17 37/26/32/+1/0/0/.../.. 25 MPH W DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 18 HIGH 59F IN 1928 LOW -11F IN 1919 PRECIP 1.44 INCHES IN 1915 SNOWFALL 7.0 INCHES IN 1904 PEAK GUST 76e MPH W IN 1978 RECORDS FOR DECEMBER 19 HIGH 59F IN 1899 LOW -1F IN 1919 PRECIP 2.06 INCHES IN 1986 SNOWFALL 14.1 INCHES IN 1945 PEAK GUST 68 MPH NE IN 1986 TODAY'S REPORT BY: Andrew Hoell