BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, DECEMBER 31, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME ARCTIC AIR MASS BRINGS BELOW NORMAL TEMPS..NOR'EASTER ON THE HORIZON The year 2013 is ending on a rather chilly note in southern New England. A surge of arctic air spread across the region overnight last night, bringing the lowest recorded temperatures in two weeks. This morning's low of 11F is eight degrees below normal and was the coldest since 7F on December 17. Conditions have also dried out a bit with dew points dipping below zero throughout much of the morning. Skies have been mostly cloudy to overcast with altocumulus, keeping temperatures in the teens through the late morning. Winds are mainly out of west-northwest, averaging 4.6 MPH since 7AM this morning. Happy New Year! Today's Observations: 7 A.M. Weather: Overcast stratocumulus, higher clouds visible Temperature: 12F; Dew Point: -3F; Wind: NW at 7 kts Sea-level pressure: 30.12 ins. Hg, decreasing, then more slowly Visibility: 70 miles, light distant haze NE-W 6-hr. min temp: 11F BHO SA 1155 E45 OVC 70 199/12/-3/3207/012/ HIER CLDS VSB LGT DSNT HZ NE-W 8/5// 56005 10015 20011 10 A.M. Weather: Broken altocumulus, scattered altocumulus, lower cumulus distant ESE-SSE and SW-W, virga all quadrants, sun dimly visible Temperature: 15F; Dew Point: 0F; Wind: WNW at 4 kts Sea-level pressure: 30.11 ins. Hg, increasing, then decreasing Visibility: 50 miles, thin smoke layer NNW BHO SA 1455 160 SCT E200 BKN 50 196/15/0/2904/011/ LWR CU DSNT ESE-SSE & SW-W VIRGA ALQDS SUN DMLY VSBL THN K LYR NNW 8/140 58003 WEATHER SUMMARY FOR MONDAY, DECEMBER 30, 2013 TEMPERATURE (DEGREES F) MAX.....39 NORMAL.....35 MIN.....17 NORMAL.....19 MEAN....28 NORMAL.....27 DEPARTURE FROM 30-YEAR NORMAL.......................+1 TOTAL DEPARTURE FOR THE MONTH.......................-2 [-0.3 DEGREE/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............37 DEPARTURE.........-1 TOTAL HEATING UNITS FOR THE MONTH............1006 DEPARTURE.........+1 TOTAL HEATING UNITS FOR THE SEASON...........2230 DEPARTURE........-37 TOTAL HEATING UNITS LAST SEASON TO DATE......1987 DIFFERENCE......+243 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..................38 W AT 11:43 A.M. AERO.......................39 W AT 11:43 A.M. ASOS.......................39 W AT 11:43 A.M. DAVIS......................33 W AT 11:42 A.M. RMY 36 FASTEST MILE FOR YESTERDAY....................27 W AT 11:43 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE.................28 W AT 11:44 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE................23 W AT 11:43 A.M. AVERAGE WIND SPEED AND DIRECTION............14.5 WSW ASOS.....................14.0 DAVIS....................12.6 W [282 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE.............-0.14 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........5.27 DEPARTURE.............+0.38 ASOS..............5.27 TOTAL PRECIPITATION FOR THE YEAR..........51.87 DEPARTURE.............-1.55 ASOS..............N/A** ** ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.......0.0 DEPARTURE.............-0.5 TOTAL SNOWFALL FOR THE MONTH............15.4 DEPARTURE.............+2.6 TOTAL SNOWFALL FOR THE SEASON...........15.6 DEPARTURE.............+0.2 PRELIMINARY CLIMATE SUMMARY FOR DECEMBER 2013 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 RMY: RMY = R.M. Young wind gust recording system added 8/9/2011 TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 12/1 45/30/38/+1/0.28/T/000/00 22 SSE AERO 23 MPH SSE RMY 23 12/2 38/34/36/0/T/0.0/000/00 15 NW AERO 15 MPH NW RMY 16 12/3 45/32/39/+3/0.00/0.0/284/51 18 NNW AERO 18 MPH NNW RMY 20 12/4 43/29/36/+1/0.00/0.0/389/70 21 WNW AERO 21 MPH WNW RMY 21 12/5 53/38/46/+11/0.02/0.0/000/00 36 S AERO 40 MPH S RMY 39 12/6 55/33/44/+9/0.38/T/000/00 25 SSW AERO 28 MPH SSW RMY N/A 12/7 40/26/33/-1/0.12/T/287/52 23 NW AERO 25 MPH NW RMY N/A 12/8 30/22/26/-8/T/T/039/07 25 NW AERO 27 MPH NW RMY N/A 12/9 41/25/33/-1/0.35/0.6/000/00 28 E AERO 28 MPH E RMY 24 12/10 33/21/27/-6/0.14/2.1/000/00 28 W AERO 28 MPH W RMY 28 12/11 28/19/24/-9/0.00/0.0/345/63 27 SW AERO 28 MPH SW RMY 27 12/12 23/14/19/-14/0.00/0.0/542/99 28 WNW AERO 31 MPH NW RMY 30 12/13 28/14/21/-11/0.00/0.0/405/74 31 W AERO 32 MPH W RMY 33 12/14 28/9/19/-13/0.45/4.8/000/00 30 E AERO 26 MPH E RMY N/A 12/15 36/21/29/-3/0.98/2.0/000/00 48 NE AERO 50 MPH NE RMY 51 12/16 27/14/21/-10/0.00/0.0/529/97 36 W AERO 37 MPH W RMY N/A 12/17 23/7/15/-16/0.53/5.5/104/19 28 N AERO 30 MPH N RMY 28 12/18 32/15/24/-7/0.00/0.0/436/80 29 WNW AERO 30 MPH NW RMY 29 12/19 42/22/32/+2/0.00/0.0/425/78 38 SW AERO 44 MPH SW RMY 42 12/20 52/34/43/+13/0.00/0.0/332/61 26 SSW AERO 29 MPH SSW RMY 29 12/21 58/42/50/+20/0.00/0.0/082/15 28 SSW AERO 29 MPH SSW RMY 30 12/22 63/35/49/+20/0.01/0.0/000/00 37 SW AERO 41 MPH SW RMY 41 12/23 37/32/35/+6/0.73/0.0/000/00 24 NW AERO 25 MPH NW RMY 25 12/24 36/25/31/+2/T/T/142/26 25 NW AERO 12/25 25/13/19/-9/0.00/0.0/480/88 29 NW AERO 30 MPH WNW RMY 30 12/26 35/19/27/-1/0.05/0.4/000/00 24 W AERO 25 MPH W RMY 25 12/27 32/22/27/-1/0.00/0.0/.../.. 25 W AERO 25 MPH W RMY 26 12/28 46/25/36/+8/0.00/0.0/.../.. 30 WSW AERO 32 MPH SW RMY 32 12/29 42/34/38/+11/1.23/0.0/000/00 36 NNE AERO 37 MPH NNE RMY 38 12/30 39/17/28/+1/0.00/0.0/000/00 38 W AERO 39 MPH W RMY 36 12/31 morning low temp: 11F; the normal low is now 19F DAILY RECORDS FOR DECEMBER 2013 12/22- NEW DAILY RECORD MAXIMUM TEMPERATURE OF 63F; surpasses previous record of 62F set in 1994 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR DECEMBER 31 HIGH 62 IN 1965 LOW -12 IN 1917 PRECIP 0.96 INS. IN 1906 SNOWFALL 7.5 INS. IN 2008 PEAK GUST 78 MPH NW IN 1990 RECORDS FOR JANUARY 1 HIGH 58F IN 1966 LOW -6F IN 1918 PRECIP 1.45 INS. IN 1982 SNOWFALL 7.2 INS. IN 1938 PEAK GUST 90e MPH S IN 1945 TODAY'S REPORT PREPARED BY: Eli Melaas