BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, JANUARY 24, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME FIRST ZERO DEGREE READING SINCE JAN. 24, 2011 NEARBY PONDS NOW NEARLY COMPLETELY FROZEN OVER This morning's low temperature of 0.0F in the Hazen shelter was our first zero or below reading since -7F on January 24, 2011. That reading was the coldest since a reading of also -7F on January 22, 2005. Windchill temperatures were in the range of 15 to 22 below zero F early this morning. The nearby ponds, Ponkapoag and Houghtons, now have 8-9/10 ice cover and may freeze over completely tonight. Winds have prevented complete ice formation during the past couple of days. Today's observations: 7 A.M. Weather: Clear, cumulus/stratocumulus layer distant offshore NE-SE, few cirrus NW-N Temperature: 0F; Dew Point: -9F; Wind: WNW at 13 kts, Windchill: -17F Sea-level pressure: 30.10 ins. Hg, rising then more rapidly Visibility: 50 miles, NW 60 miles, light distant haze Snow depth: 1 inch 24-hour precip: 0.00 inch 6-hour min temp: 0F 10 A.M. Weather: Clear, cumulus fractus, cumulus, stratocumulus distant offshore NE-SE, few cirrus SSE-SW Temperature: 8F; Dew Point: -9F; Wind: NW at 12 kts, Wind: Direction variable WSW-NNW Sea-level pressure: 30.12 ins. Hg, rising slightly BHO SA 1455 CLR 60 199/8/-9/3112/012/ CU/SC DSNT OFFSHR NE-SE FEW CI SSE-SW VSBY NW 70 LGT DSNT HZ/ 8/801 51003 1 P.M. Weather: Clear, cumulus fractus, cumulus, stratocumulus distant offshore NE-SE, few cirrus mostly distant W-NW Temperature: 16F; Dew Point: -5F; Wind: WNW at 16G25 kts, Wind: Peak wind 27 kts from W @ 12:26 P.M. Wind: Direction variable WSW-NW Sea-level pressure: 30.07 ins. Hg, falling then more rapdily Visibility: 60 miles, except 70 miles NW, light distant haze 6-hour max temp: 16F BHO SA 1755 CLR 60 184/16/-5/3016G25/007/ CUFRA/CU/SC DSNT OFFSHR NE-ESE FEW CI DSNT W-NW VSBY NW 70 LGT DSNT HZ PK WND 2827/26/ WND 25V33/ 8/801 58015 10016 20000 WEATHER SUMMARY FOR WEDNESDAY, JANUARY 23 TEMPERATURE (DEGREES F) MAX.....15 NORMAL.....34 MIN......4 NORMAL.....17 MEAN....10 NORMAL.....25 DEPARTURE FROM 30-YEAR NORMAL......................-15 TOTAL DEPARTURE FOR THE MONTH.....................+133 [+5.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............55 DEPARTURE.........+15 TOTAL HEATING UNITS FOR THE MONTH...........776 DEPARTURE........-133 TOTAL HEATING UNITS FOR THE SEASON.........2804 DEPARTURE........-409 TOTAL HEATING UNITS LAST SEASON TO DATE....2563 DIFFERENCE.......+241 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............39 W AT 12:16 P.M. AERO....................35 W AT 12:16 P.M. ASOS....................38 W AT 12:17 P.M. DAVIS...................36 N AT 11:48 A.M. RMY 37 THE FASTEST MILE FOR YESTERDAY.............29 WNW AT 12:16 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..............28 WNW AT 12:17 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............26 WNW AT 11:37 A.M. AVERAGE WIND SPEED AND DIRECTION.........15.1 WNW ASOS..................13.8 DAVIS.................13.2 W [280 deg.] * last of several occurrences 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..........0.69 DEPARTURE..........-2.57 ASOS..............0.66 TOTAL PRECIPITATION FOR THE YEAR...........0.69 DEPARTURE..........-2.57 ASOS..............0.66 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE............-0.5 TOTAL SNOWFALL FOR THE MONTH...............4.5 DEPARTURE............-8.3 TOTAL SNOWFALL FOR THE SEASON.............19.9 DEPARTURE............-8.9 PRELIMINARY CLIMATE SUMMARY FOR JANUARY 2013 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/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 1/1 35/18/27/0/0.00/0.0/313/57 44 WNW AERO 44 MPH WNW RMY 45 1/2 29/11/20/-7/0.00/0.0/457/83 35 WNW AERO 35 MPH WNW RMY 33 1/3 23/2/13/-13/0.00/0.0/529/96 24 WNW AERO 23 MPH WNW RMY 23 1/4 38/19/29/+3/0.00/0.0/320/58 35 W AERO 36 MPH W RMY 36 1/5 40/27/34/+8/0.00/0.0/536/97 36 WNW AERO 37 MPH WNW RMY 38 1/6 42/27/35/+9/T/0.1/471/85 29 SW AERO 29 MPH SW RMY 29 1/7 38/27/33/+7/0.00/0.0/538/97 29 NW AERO 27 MPH NW RMY N/A 1/8 45/27/36/+10/0.00/0.0/428/77 39 SW AERO 42 MPH SW RMY 41 1/9 42/31/37/+11/T/0.0/033/06 40 W AERO 39 MPH W RMY N/A 1/10 45/32/39/+14/0.00/0.0/548/98 47 WNW AERO 48 MPH WNW RMY 50 1/11 38/29/34/+9/0.15/0.0/050/09 23 SE AERO 21 MPH SE RMY 23 1/12 43/35/40/+15/0.02/0.0/000/00 21 SE AERO 18 MPH SE RMY 15 1/13 50/41/46/+21/0.01/0.0/000/00 30 SW AERO 30 MPH SW RMY N/A 1/14 59/40/50/+25/T/0.0/175/31 36 S AERO 37 MPH S RMY 39 1/15 40/33/37/+12/T/0.0/045/08 17 N AERO 16 MPH NNW RMY 17 1/16 33/29/31/+6/0.45/3.5/000/00 16 NNE AERO 14 MPH N RMY 15 1/17 39/28/34/+9/0.00/0.0/.../.. 36 WNW AERO 35 MPH WNW RMY 32 1/18 28/16/22/-3/0.00/0.0/.../.. 39 NW AERO 39 MPH NW RMY 43 1/19 47/21/34/+9/0.00/0.0/350/61 46 SSW AERO 45 MPH SSW RMY 48 1/20 52/26/39/+14/0.00/0.0/408/71 48 SW AERO 52 MPH SW RMY 51 1/21 26/18/22/-3/0.06/0.9/.../.. 35 WNW AERO 32 MPH WNW RMY N/A 1/22 23/10/17/-8/T/T/.../.. 35 WNW AERO 30 MPH WNW RMY 35 1/23 15/4/10/-15/0.00/0.0/.../.. 39 W AERO 35 MPH W RMY 37 1/24 morning low temp: 0F; the normal low is now 17F DAILY RECORDS FOR JANUARY 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 24 HIGH 60F IN 1967 LOW -12F IN 1907 PRECIP 2.04 INS. IN 1998 SNOWFALL 11.3 INS. IN 1935 PEAK GUST 82 MPH S IN 1996 RECORDS FOR JANUARY 25 HIGH 56F IN 2010 LOW -10F IN 1935 PRECIP 2.24 INS. IN 1979 SNOWFALL 12.5 INS. IN 1941 PEAK GUST 81 MPH WNW IN 1972 TODAY'S REPORT PREPARED BY: Robert Skilling