BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, DECEMBER 21, 2007 ALL TIMES ARE IN EASTERN STANDARD TIME DECEMBER SNOWFALL UP TO SIXTH HIGHEST ON RECORD... The total snowfall for the storm was 7.6 inches, which brings December to 28.2 inches total snowfall. Although we are almost 22 inches above normal for December, we are still not in the top 5 snowiest Decembers on record, listed below. We only need 0.8 inches to tie the 5th snowiest December with 29.0 inches in 1886. Snowiest Decembers (inches) 1) 45.2 in 1945 2) 39.5 in 1947 3) 32.0 in 1902 4) 29.7 in 2003 5) 29.0 in 1886 6) 28.2 in 2007 Today's observations: 7 A.M. Weather: Overcast stratus Temperature: 23F, Dew point: 22F, Wind: N at 7 kts Sea-level pressure: 30.47 inches Hg, rising Visibility: 3 miles, fog 6-hour min temp: 23F 24-hour precip: 0.76 ins. 24-hour snowfall: 7.1 ins. Storm total snowfall: 7.6 ins. Snow on ground: 18 inches BHO SA 1155 E4 OVC 3F 318/23/22/3507/047/ TOTAL NEW SNW PST 24 HRS 7.1 INS STORM TOTAL 7.6 INS/ 8/6// 4/018 53016 MANUAL 600X/ ASOS 60001 MANUAL 70076 ASOS 70071 10028 20023 10 A.M. Weather: Overcast stratus Temperature: 22F, Dew point: 21F, Wind: NNW at 9 kts Sea-level pressure: 30.53 inches Hg, rising Visibility: 3 miles, fog 3-hour precip: trace 3-hour snowfall: trace BHO SA 1455 E4 0VC 3F 338/22/21/3309/053/ SGBEUKN/ 8/6// 51020 MANUAL 6000/ 1 P.M. Weather: Overcast stratus, light snow Temperature: 23F, Dew point: 20F, Wind: NW at 8 kts Sea-level pressure: 30.51 inches Hg, falling Visibility: 5 miles, light snow 6-hourly max. temp: 24F 6-hour snowfall: trace BHO SA 1755 E5 OVC 5S- 333/23/20/3208/051/ THN RIME ICE SBUKN THN F/ 8/6// 56005 MANUAL 6000/ 10024 20022 WEATHER SUMMARY FOR THURSDAY, DECEMBER 20 TEMPERATURE (DEGREES F) MAX.....33 NORMAL.....37 MIN.....26 NORMAL.....22 MEAN....30 NORMAL.....30 DEPARTURE FROM 30-YEAR NORMAL............0 TOTAL DEPARTURE FOR THE MONTH.........-114 [-5.9 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............35 DEPARTURE........0 TOTAL HEATING UNITS FOR THE MONTH...........760 DEPARTURE.....+119 TOTAL HEATING UNITS FOR THE SEASON.........1840 DEPARTURE..... -90 TOTAL HEATING UNITS LAST SEASON TO DATE....1559 DIFFERENCE....+281 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............24 NNW AT 12:47 P.M. AEROVANE.............24 NNW AT 1:36 A.M. ASOS.................UNKNOWN * DAVIS................19 NW AT 12:15 P.M. FASTEST MILE FOR YESTERDAY............. 16 NW AT 8:34 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........UNKNOWN * MAXIMUM 2-MINUTE DAVIS AVERAGE..........15 NNW AT 1:49 A.M. AVERAGE WIND SPEED AND DIRECTION.......12.5 NW ASOS................UNKNOWN * DAVIS...............11.0 NW [324 deg] * ASOS WIND SYSTEM MALFUNCTION PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.76 DEPARTURE....+0.62 ASOS..............0.71 TOTAL PRECIPITATION FOR THE MONTH..........4.69 DEPARTURE....+1.78 ASOS..............4.74 TOTAL PRECIPITATION FOR THE YEAR..........43.53 DEPARTURE....-6.04 ASOS.............42.96 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........7.1 DEPARTURE.....+6.7 TOTAL SNOWFALL FOR THE MONTH...............28.2 DEPARTURE....+21.9 TOTAL SNOWFALL FOR THE SEASON..............29.0 DEPARTURE....+19.8 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2007...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 33/15/24/-12/0/0/493/88 54 WNW 12/2 24/15/20/-16/0.03/0.3/000/00 28 WNW 12/3 38/23/31/-4/0.62/1.7/000/00 47 W 12/4 27/17/22/-13/T/T/111/20 48 W 12/5 29/17/23/-12/T/T/244/44 23 WNW 12/6 28/15/22/-12/0/0/554/100 31 WNW 12/7 34/21/28/-6/0.07/0.7/000/00 24 SSW 12/8 41/25/33/0/0/0/452/82 32 W 12/9 33/25/29/-4/0.08/T/000/00 16 NW 12/10 30/26/28/-5/0.10/0/000/00 18 N 12/11 36/22/29/-3/0.09/0/258/47 25 S 12/12 44/22/36/+4/T/0/88/16 39 W 12/13 29/20/25/-7/1.08/9.2/000/00 24 ENE 12/14 37/20/29/-2/0.02/0.2/038/07 28 WSW 12/15 28/15/22/-9/0/0/.../.. 31 WNW 12/16 43/23/33/+2/1.62/8.5/000/00 54 NE 12/17 32/15/24/-7/0/0/.../.. 62 W 12/18 31/10/21/-9/0/0/.../.. 20 W 12/19 38/24/31/+1/.../.../.../.. 19 E 12/20 33/26/30/0/.../../000/00 24 NNW 12/21 morning low temp. 23F; our normal low is now 22F total snow and ice on the ground 18 inches NEW DAILY RECORDS FOR DECEMBER 2007: Dec 13: Record daily snowfall of 9.2 inches surpasses previous record of 9.0 inches in 1902. Dec.16: Record daily snowfall of 8.5 inches surpasses previousE record of 7.0 inches in 1896. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 21 HIGH 60 IN 1957 LOW -10 IN 1942 PRECIP 2.01 INS. IN 1946 SNOWFALL 11.4 INS. IN 1954 PEAK GUST 77 MPH SSE IN 1957 RECORDS FOR DECEMBER 22 HIGH 62 IN 1994 LOW -5 IN 1921 PRECIP 1.52 INS. IN 1975 SNOWFALL 8.8 INS. IN 1975 PEAK GUST 62 MPH WNW IN 1998 TODAY'S REPORT PREPARED By: Stephanie Radner