BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY MONDAY, DECEMBER 3, 2007 ALL TIMES ARE IN EASTERN STANDARD TIME UNSEASONABLY COLD TEMPERATURES AND THEN LIGHT SNOW TO RAIN TO BEGIN THE WINTER SEASON (DECEMBER THROUGH FEBRUARY) Low temperatures reached 15 degrees late Saturday evening and also very early on Sunday and Sunday's high of only 24 degrees resulted in a mean of 20 degrees, 16 degrees colder than normal. Light snow began late Sunday and changed to freezing rain and then rain early today after just 1.5 inches of accumulation. It was the first snow accumulation of the new winter season which began on December 1st. The melted precipitation totaled 0.59 inch for this event through 1 p.m. today. This could have been 5 inches of snow if there had not been a changeover to rain. The storm responsible for the precipitation was still intensifying to our northeast this afternoon. Our barometer continued falling and was down to to 29.35 inches by 1 p.m. Today's observations: 7 A.M. Weather: Obscurement with heavy fog, light rain occurring, thin glaze on surfaces Temperature: 34F, Dew point: 34F, Wind: ENE at 14 kts Sea-level pressure: 29.52 inches Hg, falling rapidly Visibility: 1/16 variable to 1/8 mile 6-hour min temp: 26F 24-hour rain and melted snow: 0.52 in. 24-hour snowfall: 1.5 ins. Snow on ground: 1 inch BHO SA 1155 W2 X 1/16VR-F 996/34/34/0714/952/ VSBY 1/16V1/8 PRESFR SFCS THN GLZ TOTAL NEW SNW PST 24 HRS 1.5 INS/ 8//// 4/001 58054 ASOS 60045 MANUAL 6XXX/ ASOS 70050 MANUAL 70052 10034 20026 10 A.M. Weather: Obscurement with heavy fog and very light drizzle occurring, intermittent light rain ended past hour Temperature: 38F, Dew point: 38F, Wind: N at 06 kts Wind: gradually backing Sea-level pressure: 29.43 inches Hg, falling Visibility: 1/16 mile mile BHO SA 1455 W2 X 1/16L-F 966/38/38/3506/943/ WND GRDLY BACKING PCPN VRY LGT REUKN/ 8//// 56030 ASOS 60005 MANUAL 6003/ 1 P.M. Weather: Obscurement with heavy fog and light rain & drizzle Temperature: 34F, Dew point: 34F, Wind: WNW at 10 kts Sea-level pressure: 29.35 inches Hg, falling Visibility: 1/16 mile mile 6-hour max. temp: 38F 6-hour precip: 0.07 in. BHO SA 1755 W1 X 1/16R-L-F 939/34/34/2910/935/ 8//// 56027 ASOS 60010 MANUAL 6007/ 10038 20034 WEATHER SUMMARY FOR SUNDAY, DECEMBER 2 TEMPERATURE (DEGREES F) MAX.....24 NORMAL.....43 MIN.....15 NORMAL.....28 MEAN....20 NORMAL.....36 DEPARTURE FROM 30-YEAR NORMAL..........-16 TOTAL DEPARTURE FOR THE MONTH..........-28 [-14 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............45 DEPARTURE......+16 TOTAL HEATING UNITS FOR THE MONTH............86 DEPARTURE......+28 TOTAL HEATING UNITS FOR THE SEASON.........1166 DEPARTURE.....-181 TOTAL HEATING UNITS LAST SEASON TO DATE....1073 DIFFERENCE.....+93 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............28 WNW AT 12:07 A.M. AEROVANE.............27 WNW AT 12:07 A.M. ASOS.................26 WNW AT 12:07 A.M. DAVIS................28 W AT 12:07 A.M. FASTEST MILE FOR YESTERDAY..............21 WNW AT 12:08 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........20 WNW AT 12:08 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........21 WNW AT 12:07 A.M. AVERAGE WIND SPEED AND DIRECTION...... 7.8 WNW ASOS............... 7.5 DAVIS.............. 7.8 W [270 deg] * Last of several occurrences. PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.52 DEPARTURE....+0.37 ASOS..............0.50 TOTAL PRECIPITATION FOR THE MONTH..........0.52 DEPARTURE....+0.22 ASOS..............0.50 TOTAL PRECIPITATION FOR THE YEAR..........39.36 DEPARTURE....-7.60 ASOS.............38.72 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........1.5 DEPARTURE.....+1.3 TOTAL SNOWFALL FOR THE MONTH................1.5 DEPARTURE.....+1.1 TOTAL SNOWFALL FOR THE SEASON...............2.3 DEPARTURE.....-1.0 PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER/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 11/1 66/42/54/+7/0/050/08 37 S 11/2 50/37/44/-2/0/446/73 29 NE 11/3 46/40/43/-3/0.95/000/00 51 N Aero 50 MPH NNW 11/4 54/37/46/0/0/503/82 33 W Aero 33 MPH W 11/5 56/40/48/+3/0/483/79 29 SE 11/6 53/37/45/0/0.75/000/00 35 SSE Aero 35 MPH SSE 11/7 50/32/41/-4/0/551/91 30 W 11/8 43/28/36/-8/0/494/82 22 W 11/9 44/32/38/-6/0.09/331/55 21 NNE 11/10 39/28/34/-10/0.05/383/64 32 N 11/11 42/24/33/-10/0/590/99 23 WNW 11/12 42/27/35/-8/0.02/024/04 25 SSE 11/13 55/42/49/+6/0.33/308/52 28 S 11/14 58/41/50/+8/0/507/86 37 S 11/15 64/40/52/+10/0.41/035/06 44 SSE Aero 46 MPH SSE 11/16 44/30/37/-5/0.31/158/27 51 W Aero 54 MPH W 11/17 40/28/34/-7/0/350/60 37 W 11/18 41/29/35/-6/0/495/85 25 ENE 11/19 36/30/33/-8/0.01/0.1/030/05 29 N 11/20 37/29/33/-7/0.09/0.7/000/00 22 SE 11/21 48/32/40/0/0.01/0/000/00 21 N 11/22 64/40/52/+12/0.01/0/212/37 36 W 11/23 40/23/32/-7/0/0/503/88 36 W 11/24 32/16/24/-15/0/0/468/82 26 WNW 11/25 48/28/38/-1/0/0/0/557/98 28 S 11/26 58/35/47/+9/0.23/0/000/00 44 S Aero 46 MPH S 11/27 61/38/50/+12/0.04/0/328/58 45 S Aero 49 MPH S 11/28 43/30/37/0/T/0/502/89 37 W 11/29 48/34/41/+4/T/0/022/04 38 S 11/30 40/30/35/-2/0/0/410/73 38 W NEW DAILY RECORDS FOR NOVEMBER 2007: NONE 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/.../.. 54 WNW 12/2 24/15/20/-16/N/A/0.3/.../.. 28 WNW 12/3 morning low temp. 23F; normal low now 28F 24 hr. precip: 0.52; snowfall 1.5 NEW DAILY RECORDS FOR DECEMBER 2007: NONE DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 3 HIGH 61 IN 1932,1950 LOW -1 IN 1890 PRECIP 2.10 INCHES IN 1986 SNOWFALL 6.0 INCHES IN 1963 PEAK GUST 73e MPH W IN 1942 RECORDS FOR DECEMBER 4 HIGH 67 IN 1998 LOW -4 IN 1940 PRECIP 1.87 INS. IN 1968 SNOWFALL 6.0 INS. IN 1907 PEAK GUST 73 MPH WNW IN 1980 TODAY'S REPORT PREPARED By: Robert Skilling