BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, JANUARY 22, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME A LITTLE BIT OF SNOW, PLENTY OF COLD Light snow that began Monday evening, and for the most part stopped by midnight, accumulated to 0.9 inch of very light, fluffy snow. The liquid equivalent was 0.06 inch, giving a snow to water ratio of 15:1. A couple of additional very light snow showers early this morning provided only a trace of snowfall. Snowfall remains more than 7 inches below the 30-year normal, and precipitation over 2 inches below normal. As an area of low pressure developed off the coast early this morning, the wind direction became WNW, ushering in a cold, dry air mass. The low so far today is 17F, but temperatures will fall much lower than that by midnight. The high has only managed to reach 23F so far, more than 10 degrees below normal. The dew point temperature has fallen into the lower single digits this afternoon. Occasional, brief periods of gusty winds in the 25-35 mph range have pushed wind chills into the lower single digits. Today's observations: 7 A.M. Weather: Scattered cumulus/stratocumulus, scattered altocumulus (2 levels), scattered thin cirrus, cumulus/stratocumulus distant NNE-SW, moderate tops distant NE-ESE, lower altocumulus distant NNE-S, higher altocumulus/altocumulus lenticularis S-NW and N, thin fog/haze all quadrants, snow shower distant SE-S moving SE, total new snow past 24 hours 0.9 inch Temperature: 17F; Dew Point: 14F; Wind: WNW at 11 kts, Wind: Direction variable W-NW Sea-level pressure: 29.80 ins. Hg, rising Visibility: 35 miles, thin fog/haze all quadrants Snow depth: 1 inch 6-hour snowfall: Trace 6-hour precip: Trace 24-hour snowfall: 0.9 inch 24-hour precip: 0.06 inch 6-hour min temp: 17F BHO SA 1155 40 SCT 60 SCT 80 SCT 250 –SCT 35 090/17/14/2911/980/ CU/SC DSNT NNE-SW MDT TOPS DSNT NE-ESE LWR AC DSNT NNE-S HIER AC/ACSL S-NW AND N THN FG/HZ ALQDS SHSN DSNT SE-S MOVG SE WND 26V32 TOTAL NEW SNW PST 24 HRS 0.9 IN/ 8/541 4/001 51010 MANUAL 6000/ MANUAL 70006 ASOS 70005 10022 20017 10 A.M. Weather: Scattered cumulus/cumulus fractus/stratocumulus, few cumulus/ cumulus fractus all quadrants, stratocumulus along/offshore with a few moderate tops distant NNE-ESE, occasional blowing/drifting snow Temperature: 20F; Dew Point: 9F; Wind: WNW at 18G26 kts, Wind: Peak wind of 27 kts. from the WNW at 9:42 AM Wind: Direction variable WSW-NNW Sea-level pressure: 29.85 ins. Hg, rising Visibility: 60 miles, light distant haze BHO SA 1455 25 SCT 60 109/20/9/3018G26/985/ FEW CU/CUFRA ALQDS SC ALG/OFFSHR FEW MDT TOPS DSNT NNE-ESE LGT DSNT HZ OCNL BLWNG/DRFTNG SNW PK WND 3027/42 WND 25V33/ 8/500 51019 1 P.M. Weather: Scattered cumulus, scattered thin cirrus, moderate cumulus WNW-N-ESE and distant SSE-SSW, cirrus distant SSE-S, light distant haze, virga/snow shower distant ENE-E moving SE Temperature: 21F; Dew Point: 2F; Wind: W at 15G24 kts, Wind: Direction variable SW-NW Sea-level pressure: 29.85 ins. Hg, falling slightly Visibility: 70 miles, light distant haze 6-hour max temp: 23F 6-hour min temp: 17F BHO SA 1755 45 SCT 250 –SCT 70 108/21/2/2715G24/985/ MDT CU WNW-N-ESE AND DSNT SSE-SSW CI DSNT SSE-S LGT DSNT HZ VIRGA/SHSN DSNT ENE-E MOVG SE WND 23V32/ 8/201 58001 10023 20017 WEATHER SUMMARY FOR MONDAY, JANUARY 21 TEMPERATURE (DEGREES F) MAX.....26 NORMAL.....34 MIN.....18 NORMAL.....17 MEAN....22 NORMAL.....25 DEPARTURE FROM 30-YEAR NORMAL.......................-3 TOTAL DEPARTURE FOR THE MONTH.....................+156 [+7.2 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............43 DEPARTURE..........+3 TOTAL HEATING UNITS FOR THE MONTH...........673 DEPARTURE........-155 TOTAL HEATING UNITS FOR THE SEASON.........2701 DEPARTURE........-432 TOTAL HEATING UNITS LAST SEASON TO DATE....2491 DIFFERENCE.......+210 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............35 WNW AT 3:25 A.M. AERO....................32 WNW AT 3:25 A.M. * ASOS....................36 NNW AT 3:25 A.M. DAVIS...................33 NW AT 3:24 A.M. RMY N/A THE FASTEST MILE FOR YESTERDAY.............26 WNW AT 3:19 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE..............24 NW AT 3:25 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............24 WNW AT 3:25 A.M. AVERAGE WIND SPEED AND DIRECTION..........9.0 W ASOS...................8.5 DAVIS..................8.0 W [277 deg.] *last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M... 0.06 DEPARTURE..........-0.08 ASOS..............0.05 TOTAL PRECIPITATION FOR THE MONTH..........0.69 DEPARTURE..........-2.29 ASOS..............0.65 TOTAL PRECIPITATION FOR THE YEAR...........0.69 DEPARTURE..........-2.29 ASOS..............0.65 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.9 DEPARTURE............+0.4 TOTAL SNOWFALL FOR THE MONTH...............4.5 DEPARTURE............-7.2 TOTAL SNOWFALL FOR THE SEASON.............19.9 DEPARTURE............-7.8 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 morning low temp: 17F; 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 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 RECORDS FOR JANUARY 23 HIGH 62F IN 1906 LOW -10F IN 1976 PRECIP 2.40 INS. IN 1935 SNOWFALL 14.6 INS. IN 1966 PEAK GUST 85 MPH S IN 1992 TODAY'S REPORT PREPARED BY: Sean Fankhauser