BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, DECEMBER 22, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME NEW RECORD MAX TEMP REACHED DESPITE LACK OF SUN, CHASED OUT BY BACK DOOR COLD FRONT This morning was accompanied by strong S-SW winds and record breaking warmth, with a high of 63.4F occurring before noon eclipsing the previous record of 62F set in 1994. A back door cold front swept in just after noon, bringing NW winds and causing temperatures to plummet close to 20 F in the hour before our 1:00 P.M. observation. Low clouds and thin fog have persisted throughout the day, thickening with the passing front and reducing visibility to 1/8 mile early in the afternoon. Today's Observations: 7 A.M. Weather: Overcast stratocumulus and cumulus fractus with thin fog Temperature: 57F; Dew Point: 57F; Wind: SSW at 12 kts, Sea-level pressure: 29.85 ins. Hg, decreasing then steady Visibility: 10 miles, thin fog Visibility: 5 miles N-ENE 6-hr. min temp: 51 24-hr rainfall: Trace Snow on ground: Trace BHO SA 1155 30 OVC 10 108/57/57/2112/985/ VSBY 5 N-ENE F/ 8/1// 56013 10057 20051 10 A.M. Weather: Overcast stratocumulus with fog of varying density Temperature: 62F; Dew Point: 58F; Wind: SW at 21G30 kts, Wind: Peak Gust: 30 kts SW @ 9:56 A.M. Sea-level pressure: 29.85 ins. Hg, rising then falling Visibility: 20 miles, fog BHO SA 1455 50 OVC 20 108/62/58/2221G30/985/ PK GUST 2330/56 VSBY 10 NW-E F 20 ESE-SSW F- 30 SW-WNW F-/ 8/4// 50005 1 P.M. Weather: Dense fog with strata drifting over the summit Temperature: 40F; Dew Point: 39F; Wind: NE at 12 kts, Sea-level pressure: 29.98 ins. Hg, increasing Visibility: 1/8 mile 6-hr max temp: 63F 6-hr min temp: 40F BHO SA 1755 W3 X 1/8F 120/40/39/0612/988/ DNS F W/ STRA DFTNG OVR SMT/ 8//// 51012 10063 20040 WEATHER SUMMARY FOR SATURDAY, DECEMBER 21, 2013 TEMPERATURE (DEGREES F) MAX.....58 NORMAL.....37 MIN.....42 NORMAL.....22 MEAN....50 NORMAL.....30 DEPARTURE FROM 30-YEAR NORMAL.....................+20 TOTAL DEPARTURE FOR THE MONTH.....................-39 [-1.9 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............15 DEPARTURE........-20 TOTAL HEATING UNITS FOR THE MONTH.............710 DEPARTURE........+36 TOTAL HEATING UNITS FOR THE SEASON...........1934 DEPARTURE........-1 TOTAL HEATING UNITS LAST SEASON TO DATE......1676 DIFFERENCE......+258 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..................28 SSW AT 10:18 A.M. AERO.......................29 SSW AT 10:20 A.M. ASOS.......................30 SSW AT 10:23 A.M. DAVIS......................28 S AT 10:23 A.M. RMY 30 FASTEST MILE FOR YESTERDAY....................23 SSW AT 5:13 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE.................23 S AT 5:14 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE................22 SSW AT 10:19 A.M. AVERAGE WIND SPEED AND DIRECTION............17.4 SSW ASOS.....................17.0 DAVIS....................16.4 SSW [202 degrees] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....Trace DEPARTURE.............-0.15 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........3.25 DEPARTURE.............-0.14 ASOS..............3.27 TOTAL PRECIPITATION FOR THE YEAR..........49.85 DEPARTURE.............-2.07 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.............-0.4 TOTAL SNOWFALL FOR THE MONTH............15.0 DEPARTURE.............+6.8 TOTAL SNOWFALL FOR THE SEASON...........15.2 DEPARTURE.............+4.4 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/.../.. 26 SSW AERO 29 MPH SSW RMY 29 12/21 58/42/50/+20/0.00/0.0/.../.. 28 SSW AERO 29 MPH SSW RMY 30 12/22 morning low temp: 50F; the normal low is now 22F DAILY RECORDS FOR DECEMBER 2013 12/22 HIGH TEMP: 63F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): 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 RECORDS FOR DECEMBER 23 HIGH 62 IN 1990 LOW -1 IN 1989 PRECIP 1.70 INS. IN 1947 SNOWFALL 11.9 INS. IN 1947 PEAK GUST 67 SSE IN 2004 TODAY'S REPORT PREPARED BY: Forrest Iwanik