BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, JANUARY 10, 2012 ALL TIMES ARE IN EASTERN STANDARD TIME MORNING SNOW SHOWERS PROVIDE 0.5 INCH OF SNOWFALL; TEMPERATURES WARMING NICELY THIS AFTERNOON Early morning snow showers, mainly between 3 a.m. and 5 a.m., provided 0.5 inch of accumulated snow. The snow melted down to 0.05 inch of liquid precipitation. This was our second measurable snowfall of the winter season. Most of the snow on the ground was gone by this afternoon. Temperatures have risen nicely this afternoon into the lower 40s. Conditions are warm once again, with the day's average temperature running nearly 10 degrees above average. Moisture in the air has been quite abundant today, and has provided for some early morning fog and also hazy conditions this afternoon. The wind direction has slowly veered around from the south this morning to a W-WNW direction this afternoon. With this shift in wind, a drier and cooler air mass is entering the region. Today's observations: 7 A.M. Weather: Scattered stratocumulus/cumulus, scattered altocumulus (2 levels), scattered cirrostratus, scattered thin cirrus, few lower stratus fractus NE-S, stratocumulus layer distant NNE-S, lower altocumulus/altocumulus lenticularis distant WSW-NE, higher altocumulus layer distant NE-E, cirrostratus distant NE, thin fog/haze below summit all quadrants, dense ground fog distant E-SSW, thin smoke layer distant all quadrants, total new snow past 24 hours 0.5 inch Temperature: 28F, Dew point: 27F, Wind: S at 8 kts Sea-level pressure: 29.86 inches Hg, rising Visibility: 25 miles, thin fog/haze below summit in all quadrants, thin smoke layer distant all quadrants 24-hour snowfall: 0.5 inch 24-hour precip: 0.05 inch 6-hour snowfall: 0.5 inch 6-hour precip: 0.05 inch 6-hour min. temp: 28F BHO SA 1155 40 SCT 60 SCT 100 SCT 200 SCT 250 –SCT 25 112/28/27/1808/986/ FEW LWR STFRA NE-S SC LYR DSNT NNE-S LWR AC/ACSL DSNT WSW-NE HIER AC LYR DSNT NE-E CS DSNT NE THN FG/HZ BLO SMT ALQDS DNS GF DSNT E-SSW THN K LYR DSNT ALQDS TOTAL NEW SNW PST 24 HRS 0.5 IN/ 8/542 4/001 57027 MANUAL 70005 ASOS 70005 MANUAL 60005 ASOS 60005 10032 20028 10 A.M. Weather: Scattered altocumulus, broken altocumulus, broken cirrus, cumulus/stratocumulus layer distant NE-SE with a few moderate tops, few altocumulus lenticularis N-E and S-WNW, cirrus layer partly thin, thin fog/haze all quadrants, thin smoke layer distant all quadrants Temperature: 32F, Dew Point: 27F; Wind: WSW at 7 kts, Wind: Direction variable SSW-W Sea-level pressure: 29.89 inches Hg, rising then falling Visibility: 35 miles, WNW 45 miles, thin fog/haze all quadrants, thin smoke layer distant all quadrants BHO SA 1455 60 SCT E90 BKN 250 BKN 35 121/32/27/2407/989/ CU/SC LYR DSNT NE-SE FEW MDT TOPS FEW ACSL N-E AND S-WNW CI LYR PRTLY THN THN FG/HZ ALQDS THN K LYR DSNT ALQDS VSBY WNW 45 WND 20V27/ 8/551 50009 1 P.M. Weather: Scattered altocumulus, broken altocumulus, broken cirrus, lone small cumulus SW, few cumulus/moderate cumulus distant WNW and distant NNW, lower altocumulus/altocumulus lenticularis distant W-N-E, hazy Temperature: 41F, Dew Point: 29F; Wind: W at 13G19 kts, Wind: Direction variable SW-WNW Sea-level pressure: 29.81 inches Hg, falling Visibility: 40 miles, hazy 6-hour max. temp: 41F BHO SA 1755 60 SCT E90 BKN 250 BKN 40 094/41/29/2613G19/981/ LONE SML CU SW FEW CU/MDT CU DSNT WNW AND DSNT NNW LWR AC/ACSL DSNT W-N-E HAZY WND 23V29/ 8/251 56027 10041 20028 WEATHER SUMMARY FOR MONDAY, JANUARY 9 TEMPERATURE (DEGREES F) MAX.....39 NORMAL.....34 MIN.....21 NORMAL.....17 MEAN....30 NORMAL.....26 DEPARTURE FROM 30-YEAR NORMAL......................+4 TOTAL DEPARTURE FOR THE MONTH.....................+61 [+6.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............35 DEPARTURE.........-4 TOTAL HEATING UNITS FOR THE MONTH............288 DEPARTURE........-57 TOTAL HEATING UNITS FOR THE SEASON..........2041 DEPARTURE.......-633 TOTAL HEATING UNITS LAST SEASON TO DATE.....2558 DIFFERENCE......-517 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............22 S AT 6:03 P.M. * AERO..................21 S AT 6:03 P.M. ASOS..................23 S AT 6:03 P.M. DAVIS.................23 S AT 5:07 P.M. RMY 24 THE FASTEST MILE FOR YESTERDAY...........16 SW AT 9:28 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE............17 SSW AT 8:33 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........17 S AT 5:08 P.M. AVERAGE WIND SPEED AND DIRECTION........9.7 SW ASOS.................9.9 DAVIS................9.0 SW [235 deg.] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.05 DEPARTURE..........-0.09 ASOS..............0.05 TOTAL PRECIPITATION FOR THE MONTH..........0.09 DEPARTURE..........-1.19 ASOS..............0.09 TOTAL PRECIPITATION FOR THE YEAR...........0.09 DEPARTURE..........-1.19 ASOS...............0.09 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.5 DEPARTURE...........0.0 TOTAL SNOWFALL FOR THE MONTH................0.6 DEPARTURE..........-3.9 TOTAL SNOWFALL FOR THE SEASON...............9.1 DEPARTURE..........-9.0 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/.../.. 36 W AERO 36 MPH W RMY 37 1/3 30/11/21/-5/0.00/0.0/.../.. 39 NW AERO 38 MPH NW RMY 39 1/4 26/7/17/-9/0.00/0.0/.../.. 28 NW AERO 25 MPH NW N/A 1/5 35/20/28/+2/T/T/.../.. 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/.../.. 29 WSW AERO 29 MPH SW RMY 30 1/8 43/26/35/+9/0.00/0.0/.../.. 28 W AERO 27 MPH W N/A 1/9 39/21/30/+4/0.00/0.0/.../.. 22 S AERO 21 MPH S RMY 24 1/10 overnight low temp: 28F; 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 10 HIGH 54F IN 2000 LOW -7F IN 2004 PRECIP 2.16 INS. IN 1935 SNOWFALL 6.3 INS. IN 1977 PEAK GUST 73e SE IN 1977 RECORDS FOR JANUARY 11 HIGH 59F IN 1975 LOW -7F IN 1968 PRECIP 1.58 INS. IN 2008 SNOW 10.2 INS. 1927 PEAK GUST 95e MPH S IN 1980 TODAY'S REPORT PREPARED BY: Sean Fankhauser