BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, JANUARY 2, 2007 ALL TIMES ARE IN EASTERN STANDARD TIME BRILLIANT RAINBOW OBSERVED EARLY THIS MORNING VISIBILITY UP TO 90 MILES EARLY THIS AFTERNOON A brilliant rainbow was observed around 8 to 8:30 a.m. this morning to our NW as a light rain shower passed by leaving just a trace of rain. We're reporting our maximum visibility value early this afternoon but it could be closer to 100 miles if there was anything out there that far away on the horizon. The Monadnocks are standing out very clearly 60 to 70 miles to the northwest. NEW YEAR'S DAY RAINSTORM BROUGHT AN INCH OF RAINFALL HIGH TEMPERATURE OF 53 DEGREES, THE DAY 15 DEG. ABOVE NORMAL UNSTEADY BAROMETRIC PRESSURE VERY NOTICEABLE ON OUR CHARTS The New Years Day rainstorm which began as some light freezing rain before dawn became a mild light to moderate rain later in the day and the temperature soared all the way to 53 degrees by early evening. An unusually unsteady barometric trace was recorded between about 6 p.m. and 11 p.m. as a weather front separating very warm air to the south and colder air to the north was wavering north- south in the local area. Changes up and down in pressures reached 0.06 to 0.08 inch at times in very short intervals of 5 to 15 minutes throughout the period. * [correction to sunshine for December below] DECEMBER 2006 DATA WARMEST DECEMBER ON RECORD! BY ALMOST A DEGREE 1. 38.1 IN 2006 2. 37.3 IN 2001 3. 37.2 IN 1891 4. 36.9 IN 1998 5. 36.7 IN 1990 Av. Max. 45.5 Av. Min. 31.2 Mean 38.4 [+7.2] 24-hour corr. mean temp: 38.1 deg.[for our historical record] High 65/1st Low 17/8th HDD 820 [-220] HDD Season 1873 [-456] CDD 0 CDD Season 641 [+83] Precipitation: 2.24 ins. [-2.32 ] Snowfall: 3.7 ins. [-7.0 ] * Sunshine: 7767 corrected mins. or 46% [corrected from 47%] of possible or exactly normal for the month. Wind: Av. (corrected) 14.0 MPH Prevailing: W 20% Peak gust: 63 MPH S/1st Today's observations: 7 A.M. Weather: Clear with few clouds Temperature: 39F, Dew point: 34F, Wind: W at 18G29 kts Sea-level pressure: 29.75 inches Hg, rising Visibility: 50 miles 6-hourly min. temp. 37 deg. 24-hourly precip: 0.88 in. BHO SA 1155 CLR 50 073/39/34/2618G29/975/ SC DSNT SW-N AC/ACSL NNE-S AC LYR ALG NE-E HRZN PK WND 2630/33/ 8/540 MANUAL 6000/ MANUAL 70088 ASOS 70087 10040 20037 10 A.M. Weather: Scattered stratocumulus clouds Temperature: 40F, Dew point: 29F, Wind: W at 20G33 kts Wind: Peak wind 36 kts W past hour Sea-level pressure: 29.91 inches Hg, rising Visibility: 80 miles BHO SA 1455 35 SCT 80 127/40/29/2820G33/991/ PK WND 2936/32/ 8/500 53054 1 P.M. Weather: Clear, few stratocumulus clouds NNW-NE-ESE Temperature: 41F, Dew point: 20F, Wind: W at 21G34 kts Wind: Peak wind 38 kts W past hour Sea-level pressure: 29.96 inches Hg, rising Visibility: 90 miles BHO SA 1755 CLR 90 147/41/20/2821G34/996/ FEW SC NNW-NE-ESE PK WND 2738/33/ 8/500 51020 6000/ 10042 20039 WEATHER SUMMARY FOR MONDAY, JANUARY 1, NEW YEAR'S DAY TEMPERATURE (DEGREES F) MAX.....53 NORMAL.....35 MIN.....30 NORMAL.....19 MEAN....42 NORMAL.....27 DEPARTURE FROM 30-YEAR NORMAL........+15 TOTAL DEPARTURE FOR THE MONTH....... +15 HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY..........23 DEPARTURE......-15 TOTAL HEATING UNITS FOR THE MONTH......... 23 DEPARTURE......-15 TOTAL HEATING UNITS FOR THE SEASON.......1896 DEPARTURE.....-471 TOTAL HEATING UNITS LAST SEASON TO DATE..2190 DIFFERENCE....-294 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...........38 SE AT 10:03 A.M. AEROVANE............37 SE AT 10:07 A.M. * ASOS................37 SE AT 10:52 A.M. DAVIS...............38 SE AT 10:05 A.M. FASTEST MILE FOR YESTERDAY.............29 SE AT 10:08 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..........29 SE AT 10:08 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.........29 ESE AT 11:00 A.M. AVERAGE WIND SPEED AND DIRECTION..... 15.5 SE ASOS.............. 14.6 DAVIS............. 15.7 SE [140 deg] * last of several occurrences.. PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.88 DEPARTURE.....+0.73 ASOS..............0.87 TOTAL PRECIPITATION FOR DECEMBER...........2.24 DEPARTURE.....-2.32 ASOS..............2.29 TOTAL PRECIPITATION FOR 2006..............60.35 DEPARTURE.....+9.57 ASOS.............59.91 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE..... 0.5 TOTAL SNOWFALL FOR DECEMBER.................3.7 DEPARTURE.....-7.0 TOTAL SNOWFALL FOR THE SEASON...............3.7 DEPARTURE....-10.4 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2006......CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available 12/1 65/59/62/+26/0.42/0.0/000/00 63 S Aero 65 S 12/2 60/35/48/+12/0/0/0/551/99 47 W Aero 44 W 12/3 44/29/37/+2/0/0/0/506/91 29 S 12/4 38/25/32/-3/0.28/3.2/344/62 38 WNW Aero 40 WNW 12/5 32/22/27/-8/0/0/255/46 23 W 12/6 44/21/33/-1/0/0/171/31 43 SSE Aero 41 SSE 12/7 53/33/43/+9/T/T/435/79 37 W 12/8 33/17/25/-8/T/T/215/39 45 W Aero 46 WNW 12/9 36/19/28/-5/0/0/341/62 31 SSW 12/10 51/32/42/+9/0/0/516/94 35 SSW 12/11 47/35/41/+9/T/0/071/13 25 WSW 12/12 42/30/36/+4/0/0/400/73 28 SSE 12/13 50/37/44/+12/0/0.11/005/01 31 SE 12/14 56/42/49/+18/0/0/410/75 25 S 12/15 52/42/47/+16/0/0/000/00 31 S 12/16 50/35/43/+12/0.03/0/545/100 35 W 12/17 53/33/43/+12/0/0/131/24 35 SSW 12/18 52/38/45/+15/0.01/0/000/00 29 W 12/19 41/28/35/+5/0/0/441/81 29 WNW 12/20 42/25/34/+4/0/0/534/98 35 S 12/21 48/36/42/+12/0/0/218/40 33 SSW 12/22 42/29/36/+7/0.06/0/190/35 25 NW 12/23 56/39/48/+19/0.79/0/000/00 33 SE 12/24 48/36/42/+13/0/0/262/48 54 W Aero 53 W 12/25 43/33/38/+9/0.13/0/164/30 29 W 12/26 46/36/41/+13/0.34/0/000/00 35 E 12/27 40/30/35/+7/0.02/0/093/17 37 W Aero 34 W 12/28 42/28/35/+7/0/0/197/36 30 SW Aero 32 SW 12/29 33/21/27/-1/0/0/427/78 28 NW 12/30 33/21/27/-1/0.06/0.4/000/00 35 WNW Aero 36 WNW 12/31 37/22/30/+3/0/0/532/97 25 NW 1/1 53/30/42/+15/0.88/0/000/00 38 SE 1/2 morning low temp. 37 deg; normal now 19 deg. NEW DAILY DECEMBER RECORDS 12/1- New daily and monthly record high minimum temperature 59; previous daily record 50 in 1908 and 1934, previous monthly record 53 on 4 and 6 December 1982 and on 22 and 23 December 1990. In addition: NEW HIGHEST MINIMUM TEMPERATURE SO LATE IN YEAR, 59 deg; previous record 57 deg. 11/17/1927. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 2 HIGH 62F IN 1890 LOW -7F IN 1899,1918 PRECIP 2.10 INS. IN 1987 SNOWFALL 9.0 INS. IN 1904 PEAK GUST 85e MPH S IN 1942 RECORDS FOR JANUARY 3 HIGH 64F IN 2000 LOW -4F IN 1904 PRECIP 1.93 INS. IN 1999 SNOW 11.3 INS. 1996 WIND 92 MPH S IN 1960 TODAY'S REPORT By: Robert Skilling