BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, JANUARY 16, 2011 ALL TIMES ARE IN EASTERN STANDARD TIME TEMPERATURES ON THE RISE LAST EVENING TO 30F BY MIDNIGHT WINDS FROM THE SOUTH AND SOUTHWEST LATE YESTERDAY INTO EARLY THIS MORNING ARE VEERING WESTERLY AS NEW COLD AIR MASS IS TO START ARRIVING TODAY After the coldest air mass of the season to date which sent the thermometer down to 8F early yesterday morning, temperatures were rising steadily late yesterday reaching 30 degrees by late last evening continuing past midnight early today. Colder air arrived by dawn with a low of 25 degrees. This is well above the normal low of 18F but falling temperatures later today will likely drop today’s minimum well down into the teens. Today's observations: 7 A.M. Weather: Clear, altocumulus, few altocumulus lenticularis northeast thru south, cirrus radiatus distant SE-S Temperature: 25F, Dew point: 17F; Wind: WSW at 12 kts, Sea-level pressure: 29.88 inches Hg, rising Visibility: 20 miles, hazy 6-hour min. temp: 25F 24-hour precip: 0.01 in. 24-hour snowfall: 0.3 in. Total snow depth on ground: 15 inches BHO SA 1155 CLR 20 117/25/17/2512/988/ AC/FEW ACSL NE-S CI DSNT SE-S HAZY TOTAL NEW SNW PST 24 HRS 0.3 IN/ 8/031 4/015 51013 ASOS 70003 MANUAL 70001 10030 20025 10 A.M. Weather: Clear, few stratocumulus distant WNW, few cirrus SE-S Temperature: 27F, Dew point: 16F; Wind: W at 15G27 kts, Wind: Peak wind from W at 28 kts at 9:42 a.m. Wind: Direction variable WSW to NW Sea-level pressure: 29.95 inches Hg, rising Visibility: 25 miles, hazy BHO SA 1455 CLR 25 142/27/16/2715G27/995/ FEW SC DSNT WNW FEW CI SE-S HAZY PK WND 2628/42 WND 24V31/ 8/501 51025 WEATHER SUMMARY FOR SATURDAY, JANUARY 15 TEMPERATURE (DEGREES F) MAX.....30 NORMAL.....34 MIN......8 NORMAL.....18 MEAN....19 NORMAL.....26 DEPARTURE FROM 30-YEAR NORMAL.................-7 TOTAL DEPARTURE FOR THE MONTH................+19 [+1.1 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............46 DEPARTURE........+7 TOTAL HEATING UNITS FOR THE MONTH...........561 DEPARTURE.......-18 TOTAL HEATING UNITS FOR THE SEASON.........2813 DEPARTURE.......-95 TOTAL HEATING UNITS LAST SEASON TO DATE....2863 DIFFERENCE......-50 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..............28 SSW AT 10:38 P.M. * AEROVANE...............23 NNW AT 2:07 A.M. ASOS...................29 SSW AT 10:38 P.M. DAVIS..................31 SSW AT 10:07 P.M. THE FASTEST MILE FOR YESTERDAY........... 22 SSW AT 10:39 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE.............22 SSW AT 10:39 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE............23 SSW AT 10:39 P.M. AVERAGE WIND SPEED AND DIRECTION..........12.1 WNW ASOS...................12.0 DAVIS..................11.6 SSW [210 DEG] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.01 DEPARTURE........-0.15 ASOS..............0.03 TOTAL PRECIPITATION FOR THE MONTH..........2.42 DEPARTURE........+0.10 ASOS..............1.79** TOTAL PRECIPITATION FOR THE YEAR...........2.42 DEPARTURE........+0.10 ASOS...............1.79** **ASOS missing precipitation due to system failure on 1/12-13 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.3 DEPARTURE........-0.2 TOTAL SNOWFALL FOR THE MONTH...............20.7 DEPARTURE.......+13.2 TOTAL SNOWFALL FOR THE SEASON..............43.7 DEPARTURE.......+22.6 PRELIMINARY CLIMATE SUMMARY FOR JANUARY 2011 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust when significant TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 1/1 57/37/47/+20/0.00/0.0/318/58 25 S 1/2 47/33/40/+13/0.21/0.0/000/00 38 WNW AERO 44 MPH WNW 1/3 33/23/28/+1/0.00/0.0/539/98 40 NW AERO 48 MPH NW 1/4 37/21/29/+2/0.00/0.0/408/74 29 SSW AERO 35 MPH SSW 1/5 37/22/30/+3/0.00/0.0/497/90 35 W AERO 38 MPH W 1/6 30/17/24/-2/0.00/0.0/421/76 16 WNW 1/7 33/20/27/+1/T/T/117/21 19 NNE 1/8 30/26/28/+2/0.14/1.7/.../.. 23 NNW 1/9 32/20/26/0/0.02/0.5/.../.. 38 W AERO 42 MPH W 1/10 33/18/26/0/0.00/0.0/.../.. 32 WNW AERO 37 MPH WNW 1/11 30/16/23/-3/0.00/0.0/.../.. 22 NNW 1/12 31/24/26/+2/2.04/18.2/000/00/ 52 NNE AERO 1/13 28/16/22/-4/0.00/0.0/.../.. 35 NW AERO 39 MPH NW 1/14 23/11/17/-9/T/T/.../.. 21 NNW 1/15 30/8/19/-7/0.01/0.3/.../.. 28 SSW AERO 33 MPH SSW 1/16/ our morning low temp: 25F; the normal low is now 18F DAILY RECORDS FOR JANUARY 2011 1/12 - NEW RECORD PRECIPITATION OF 2.04 INCHES; surpasses the previous record of 1.46 inches in 1900 1/12 - NEW RECORD SNOWFALL OF 18.2 INCHES; surpasses the previous record of 6.0 inches in 1923 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 16 HIGH 63F IN 1995 LOW -12F IN 2004 PRECIP 1.32 INS. IN 1936 SNOWFALL 14.0 INS. IN 1965 PEAK GUST 79 MPH WNW IN 1960 RECORDS FOR JANUARY 17 HIGH 55F IN 1973,1995 LOW -8F IN 1907,1982 PRECIP 1.43 INS. IN 1956 SNOWFALL 13.4 INS. IN 1956 PEAK GUST 62 MPH S IN 1994 TODAY'S REPORT PREPARED BY: Robert Skilling