BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, JANUARY 21, 2012 ALL TIMES ARE IN EASTERN STANDARD TIME LIGHT SNOW WITH OCCASSIONAL MODERATE SNOW ON THE SUMMIT TODAY... STORM TOTAL 2.4 INCHES AT 1 PM... Snow began on the hill shorly after 6 AM this morning, and it began accumulating quickly on the cold ground. The first 0.1 inch was measured at 7 AM with a temperature of 16 degrees. Snow continued generally light into early afternoon with a 45 minute burst of moderate snow from 9:30 to 10:15 AM. The greatest hourly snow amount so far today was 0.7 inch from 9-10 AM. An additional 2.3 inches was measured in the six hours ending at 1 PM, bringing the storm total so far to 2.4 inches. The melted equivalent precipitation for the storm through 1 PM is 0.19 inch, which is a 13:1 snow to liquid ratio. Another band of moderate snow began before 2 PM and continues as of 2:30 PM. Today's observations: 7 A.M. Weather: Sky partly obscured in light snow, snow began 6:15 AM Temperature: 16F, Dew point: 11F, Wind: NE at 8 kts Sea-level pressure: 30.21 inches Hg, falling Visibility: 3 miles 24-hour precip: Trace 24-hour snowfall: 0.1 inch Snow depth: 2 inches 6-hour min. temp: 16F BHO SA 1155 –X E20 OVC 3S- 231/16/11/0408/021/ S1 S-B15 TOTAL NEW SNW PST 24 HRS 0.1 IN/ 8/6// 4/002 56020 6000/ 10018 20016 10 A.M. Weather: Sky obscured; moderate snow and fog, snow depth increasing rapidly (0.7 inch in past hour), total new snow past 3 hours 1.4 inches Temperature: 16F, Dew Point: 16F; Wind: N at 8 kts Sea-level pressure: 30.21 inches Hg, falling slightly Visibility: 1/2 mile 3-hour snowfall: 1.4 inches BHO SA 1455 W4 X 1/2SF 229/16/16/3608/021/ SNOINCR 1/3 TOTAL NEW SNW PST 3 HRS 1.4 INS STORM TOTAL 1.5 INS/ 8/6// 58002 60/// 1 P.M. Weather: Sky obscured; light snow and fog, occassional drifting snow, total new snow past 6 hours 2.3 inches Temperature: 19F, Dew Point: 18F; Wind: N at 10 kts Sea-level pressure: 30.11 inches Hg, falling Visibility: 3/4 mile 6-hour precipitation: 0.19 inch 6-hour snowfall: 2.3 inches 6-hour max. temp: 19F BHO SA 1755 W4 X 3/4S-F 197/19/18/3610/011/ OCNL DRFTG SNW TOTAL NEW SNW PST 6 HRS 2.3 INS STORM TOTAL 2.4 INS/ 8/6// 56032 6019/ 10019 20015 WEATHER SUMMARY FOR FRIDAY, JANUARY 20 TEMPERATURE (DEGREES F) MAX.....29 NORMAL.....33 MIN.....17 NORMAL.....17 MEAN....23 NORMAL.....25 DEPARTURE FROM 30-YEAR NORMAL......................-2 TOTAL DEPARTURE FOR THE MONTH.....................+99 [+4.8 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............42 DEPARTURE.........+3 TOTAL HEATING UNITS FOR THE MONTH............690 DEPARTURE........-84 TOTAL HEATING UNITS FOR THE SEASON..........2443 DEPARTURE.......-660 TOTAL HEATING UNITS LAST SEASON TO DATE.....3013 DIFFERENCE......-570 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............30 W AT 12:47 P.M. AERO..................30 W AT 12:47 P.M. ASOS..................30 W AT 12:47 P.M. DAVIS.................29 WNW AT 11:33 A.M. RMY 30 THE FASTEST MILE FOR YESTERDAY...........21 W AT 12:47 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE............21 WNW AT 11:22 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........20 WNW AT 11:22 A.M. AVERAGE WIND SPEED AND DIRECTION.......12.4 WNW ASOS................12.0 DAVIS...............10.7 W [278 deg] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...Trace DEPARTURE..........-0.14 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.90 DEPARTURE..........-0.94 ASOS..............1.90 TOTAL PRECIPITATION FOR THE YEAR...........1.90 DEPARTURE..........-0.94 ASOS...............1.90 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.1 DEPARTURE..........-0.4 TOTAL SNOWFALL FOR THE MONTH................4.2 DEPARTURE..........-5.8 TOTAL SNOWFALL FOR THE SEASON..............12.7 DEPARTURE.........-10.9 PRELIMINARY CLIMATE SUMMARY FOR JANUARY 2012 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 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 51/35/42/+16/0.01/0.0/494/90 35 S AERO 35 MPH S RMY 37 1/2 48/30/39/+12/0.02/T/346/63 36 W AERO 36 MPH W RMY 37 1/3 30/11/21/-5/0.00/0.0/446/81 39 NW AERO 38 MPH NW RMY 39 1/4 26/7/17/-9/0.00/0.0/468/85 28 NW AERO 25 MPH NW RMY N/A 1/5 35/20/28/+2/T/T/166/30 27 W AERO 25 MPH W RMY 26 1/6 47/23/35/+9/0.01/0.1/.../.. 26 S AERO 25 MPH S RMY 27 1/7 59/39/49/+23/0.00/0.0/477/86 29 WSW AERO 29 MPH SW RMY 30 1/8 43/26/35/+9/0.00/0.0/367/66 28 W AERO 27 MPH W RMY N/A 1/9 39/21/30/+4/0.00/0.0/384/69 22 S AERO 21 MPH S RMY 24 1/10 43/28/36/+11/0.05/0.5/379/68 29 WNW AERO 30 MPH WNW RMY 32 1/11 38/27/33/+8/0.00/0.0/448/80 24 E AERO 24 MPH E RMY N/A 1/12 40/31/36/+11/1.37/0.1/000/00 52 ENE AERO 52 MPH NE RMY 49 1/13 50/27/39/+14/0.06/T/174/31 63 SW AERO 67 MPH SW RMY 67 1/14 33/16/25/0/0.00/0.0/451/80 36 WSW AERO 37 MPH WSW RMY 35 1/15 16/4/10/-15/0.00/0.0/555/98 36 NW AERO 36 MPH NW RMY 37 1/16 31/5/18/-7/0.11/1.2/408/72 32 SSW AERO 32 MPH SSW RMY N/A 1/17 46/31/39/+14/0.11/0.4/000/00 35 SW AERO 36 MPH SW RMY N/A 1/18 49/18/34/+9/0.00/0.0/564/99 56 WNW AERO 55 MPH WNW RMY 56 1/19 28/12/20/-5/0.10/1.1/.../.. 27 SE AERO 28 MPH ESE RMY 28 1/20 29/17/23/-2/0.06/0.7/.../.. 30 W AERO 30 MPH W RMY 30 1/21 the morning low temp: 15F; the normal low is now 17F DAILY RECORDS FOR JANUARY 2012 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 21 HIGH 65F IN 1906 LOW -4F IN 1888,1893 PRECIP 2.49 INS. IN 1979 SNOWFALL 7.6 INS. IN 2011 PEAK GUST 78e MPH SE IN 1979 RECORDS FOR JANUARY 22 HIGH 59F IN 1916 LOW -8F IN 1888,1976 PRECIP 1.24 INS. IN 1891,1987 SNOWFALL 10.0 INS. IN 2005 PEAK GUST 67 MPH W IN 1976 TODAY'S REPORT PREPARED BY: Mike Iacono