BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, JANUARY 17, 2015 ALL TIMES ARE IN EASTERN STANDARD TIME ARCTIC COLD AND SUNSHINE MAKE BRIEF RETURN TODAY WITH DIMINISHING WINDS... They sky has been nearly completely cloud free today with only a few stratocumulus visible over the ocean to the east and a few occasional mid-level clouds appearing to the west this afternoon. The low temperature of 5F this morning was the coldest since January 8th, and the wind chill early this morning was in the -5 to -10F range. The strongest winds so far today occurred shortly after midnight and have been diminishing to become light and variable by early afternoon. The visibility has been excellent at 70-75 miles much of the day. Today's Observations: 7 A.M. Weather: Clear, few stratocumulus along the horizon offshore and distant NE-ESE Temperature: 6F; Dew Point: -6F; Wind: NW at 8 kts Sea-level pressure: 30.32 ins. Hg, rising steadily Visibility: 70 miles, 80 miles SE-SW 6-hr max temp: 11F 6-hr min temp: 5F 24-hr precip.: Trace 24-hr snowfall: Trace Snow Depth: Trace BHO SA 1155 CLR 70 266/6/-6/3208/032/ FEW SC ALG HRZN OFFSHR DSNT NE-ESE VSBY SE-SW 80/ 8/500 52033 10011 20005 10 A.M. Weather: Clear, few stratocumulus along horizon offshore and distant NE-ESE Temperature: 11F; Dew Point: -5F; Wind: NW at 9 kts, Sea-level pressure: 30.37 ins. Hg, rising slightly Visibility: 75 miles BHO SA 1455 CLR 75 283/11/-5/3209/037/ FEW SC ALG HRZN OFFSHR DSNT NE-ESE/ 8/500 52017 1 P.M. Weather: Clear, few stratocumulus distant ENE-ESE, few altocumulus SW-NW Temperature: 18F; Dew Point: -4F; Wind: NNW at 4 kts, Wind: Light Sea-level pressure: 30.32 ins. Hg, falling then more rapidly Visibility: 75 miles 6-hr max temp: 19F 6-hr min temp: 6F BHO SA 1755 CLR 75 266/18/-4/3404/032/ FEW SC DSNT ENE-ESE FEW AC SW-NW WND LGT/ 8/503 58017 10019 20006 SUMMARY FOR FRIDAY, JANUARY 16, 2015 TEMPERATURE (DEGREES F) MAX.....35 NORMAL.....33 MIN.....12 NORMAL.....17 MEAN....24 NORMAL.....25 DEPARTURE FROM 30-YEAR NORMAL..........................-1 TOTAL DEPARTURE FOR THE MONTH.........................-43 [-2.9 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............41 DEPARTURE...........+1 TOTAL HEATING UNITS FOR THE MONTH.............672 DEPARTURE..........+45 TOTAL HEATING UNITS FOR THE SEASON...........2732 DEPARTURE.........-200 TOTAL HEATING UNITS LAST SEASON TO DATE......2873 DIFFERENCE........-141 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..................46 W AT 4:08 P.M. ASOS.......................53 WNW AT 4:08 P.M. DAVIS......................48 WNW AT 4:07 P.M. RMY 50 FASTEST MILE FOR YESTERDAY....................39 W AT 4:11 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE.................37 W AT 4:09 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE................34 W AT 4:09 P.M. AVERAGE WIND SPEED AND DIRECTION............17.2 WSW ASOS.....................16.3 DAVIS....................14.9 W [272 degrees] * last of several occurrences.... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...Trace DEPARTURE.....-0.14 ASOS.............Trace TOTAL PRECIPITATION FOR THE MONTH..........1.58 DEPARTURE.....-0.70 ASOS..............1.60 TOTAL PRECIPITATION FOR THE YEAR...........1.58 DEPARTURE.....-0.70 ASOS..............1.60 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M........Trace DEPARTURE......-0.5 TOTAL SNOWFALL FOR THE MONTH................4.9 DEPARTURE......-4.1 TOTAL SNOWFALL FOR THE SEASON..............15.9 DEPARTURE......-9.1 PRELIMINARY CLIMATE SUMMARY FOR JANUARY CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY GUST RMY: R.M. Young wind gust recording system TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 1/1 31/18/25/-2/0.00/0.0/544/99 29 SSW RMY 30 1/2 37/26/32/+5/0.00/0.0/314/57 35 WSW RMY 38 1/3 34/21/28/+2/0.67/2.5/017/03 25 SE RMY 26 1/4 51/33/42/+16/0.48/0.0/000/00 30 SSW RMY N/A 1/5 46/13/30/+4/0.00/0.0/542/98 48 W RMY 54 1/6 15/10/13/-13/0.02/0.4/000/00 29 W RMY N/A 1/7 22/01/12/-14/0.01/0.3/394/71 43 WNW RMY 47 1/8 16/-5/6/-20/0.00/0.0/539/97 39 WNW RMY N/A 1/9 27/16/22/-4/0.08/0.9/.../.. 35 WSW RMY 38 1/10 22/11/17/-8/0.00/0.0/541/97 26 WNW RMY 27 1/11 31/9/20/-5/45/0.00/0.0/123/22 26 SSW RMY N/A 1/12 36/31/34/+9/0.23/T/000/00 29 NNW RMY N/A 1/13 33/11/22/-3/0.00/0.0/524/93 30 NNW RMY 29 1/14 22/11/17/-8/T/T/000/00 18 NNW RMY 16 1/15 27/20/24/-1/0.09/0.8/000/00 20 WSW RMY 22 1/16 35/12/24/-1/T/T/.../.. 46 WSW RMY 50 1/17 morning low temp: 5F since midnight; normal low is now 17F DAILY RECORDS FOR JANUARY 2015 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JANUARY 17 HIGH 55F IN 1973,1995 LOW -8F IN 1907,1982 PRECIP 1.43 INS. IN 1956 SNOWFALL 13.4 INS. IN 1956 PEAK GUST 62 MPH S IN 1994 RECORDS FOR JANUARY 18 HIGH 62F IN 1973,1990 LOW -10F IN 1982 PRECIP 1.68 INS. IN 1915 SNOWFALL 13.0 INS. IN 1948 PEAK GUST 85 MPH SSE IN 2006 TODAY'S REPORT PREPARED BY: Mike Iacono / Rob Millette If you do not wish to receive this Daily Discussion and Climate Summary from the Blue Hill Observatory, please send an email to bfitzgerald@bluehill.org.