BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, NOVEMBER 15, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME STRONG TEMPERATURE INVERSION THIS MORNING; TEMPERATURES MODERATING NICELY WITH VERY DRY AIR MASS A strong temperature inversion was quite apparent by taking a look at morning lows this morning: Blue Hill 38F, Hingham 28F, Plymouth 26F, and nearby Norwood 21F. It was cold enough in the lower elevations for a thin layer of ice to form and cover about 10-20% of Ponkapoag Pond. Some impressive looming of the distant mountains also occurred this morning with the temperature inversion, making the mountains look much larger than reality. Temperatures have warmed up nicely this afternoon, nearing 60F here on the summit. Today is a solid 10 degrees warmer than yesterday, and will likely finish several degrees above normal for the date. The air mass is very dry despite persistent SW winds today. Dew point temperatures have been down in the teens to near 20F, producing very low relative humidity this afternoon of 20-25%. Today's Observations: 7 A.M. Weather: Scattered altocumulus, broken thin cirrus, few cirrocumulus, inversion present, small smoke plume distant S drifting ENE, thin smoke layer distant all quadrants, distant haze Temperature: 40F; Dew Point: 15F; Wind: SW at 12 kts. Sea-level pressure: 30.20 ins. Hg, rising then rising more quickly Visibility: 65 miles, distant haze 6-hr min temp: 38F BHO SA 1155 140 SCT 250 –BKN 65 228/40/15/2212/020/ FEW CC INVSN PRSNT SML K PLUME DSNT S DRFTNG ENE THN K LYR DSNT ALQDS DSNT HZ/ 8/049 51014 10040 20038 10 A.M. Weather: Scattered altocumulus, scattered cirrostratus, broken thin cirrus, cirrostratus invading, few cirrocumulus mostly WNW-NNE, inversion present, small smoke plume distant S, smoke layer along/above horizon all quadrants, hazy Temperature: 49F; Dew Point: 20F; Wind: SW at 6 kts. Sea-level pressure: 30.22 ins. Hg, rising slightly then steady Visibility: 65 miles, hazy, smoke layer along/above horizon all quadrants BHO SA 1455 140 SCT 200 SCT 250 –BKN 233/49/20/2206/022/ CS INVADING FEW CC MSTLY WNW-NNE INVSN PRSNT SML K PLUME DSNT S K LYR ALG/ABV HRZN ALQDS HAZY/ 8/049 52005 1 P.M. Weather: Scattered cirrostratus, scattered dense cirrus, broken thin cirrus, few altocumulus all quadrants, few cirrocumulus all quadrants and overhead, parahelion, thin smoke layer distant W-N-ESE, dark smoke layer distant NNE-ENE, hazy Temperature: 57F; Dew Point: 21F; Wind: SSW at 12 kts, Wind: Direction variable S-SW Sea-level pressure: 30.16 ins. Hg, falling then falling more rapidly Visibility: 65 miles, hazy 6-hr max temp: 59F BHO SA 1755 200 SCT 220 SCT 250 –BKN 65 215/57/21/2012/016/ FEW AC ALQDS FEW CC ALQDS AND OVHD PARHELION THN K LYR DSNT W-N-ESE DRK K LYR DSNT NNE-ENE HAZY WND 17V23/ 8/049 58018 10059 20040 WEATHER SUMMARY FOR THURSDAY, NOVEMBER 14, 2013 TEMPERATURE (DEGREES F) MAX.....49 NORMAL.....51 MIN.....26 NORMAL.....34 MEAN....38 NORMAL.....42 DEPARTURE FROM 30-YEAR NORMAL......................-4 TOTAL DEPARTURE FOR THE MONTH.....................-17 [-1.4 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............27 DEPARTURE.........+4 TOTAL HEATING UNITS FOR THE MONTH.............311 DEPARTURE........+22 TOTAL HEATING UNITS FOR THE SEASON............788 DEPARTURE........-64 TOTAL HEATING UNITS LAST SEASON TO DATE.......710 DIFFERENCE.......+78 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY..................25 W AT 11:31 A.M. AERO.......................25 W AT 11:31 A.M. ASOS.......................27 WSW AT 11:22 A.M. DAVIS......................26 WSW AT 11:22 A.M. RMY 28 FASTEST MILE FOR YESTERDAY....................20 W AT 11:31 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE.................21 W AT 11:32 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE................18 WSW AT 11:22 A.M. AVERAGE WIND SPEED AND DIRECTION............14.3 SW ASOS.....................13.8 DAVIS....................13.0 SW [232 degrees] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE............-0.16 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.66 DEPARTURE............-1.54 ASOS..............0.64 TOTAL PRECIPITATION FOR THE YEAR..........43.61 DEPARTURE............-2.30 ASOS..............N/A** **ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.......0.0 DEPARTURE..............0.0 TOTAL SNOWFALL FOR THE MONTH.............0.2 DEPARTURE.............-0.3 TOTAL SNOWFALL FOR THE SEASON............0.2 DEPARTURE.............-0.6 PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 2013 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 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 11/1 68/56/62/+16/0.10/0.0/012/02 60 SSW AERO N/A N/A RMY 66 11/2 65/49/57/+11/0.00/0.0/296/48 22 WSW AERO N/A N/A RMY 23 11/3 49/30/40/-6/0.06/T/135/22 23 N AERO N/A N/A RMY N/A 11/4 42/27/35/-10/0.00/0.0/588/96 24 NNE AERO N/A N/A RMY 25 11/5 50/29/40/-5/0.00/0.0/487/80 16 SSW AERO N/A N/A RMY 17 11/6 59/40/50/+5/0.00/0.0/419/69 30 SSW AERO 31 MPH SSW RMY 33 11/7 65/37/51/+6/0.31/0.0/079/13 33 SW AERO 37 MPH SW RMY 37 11/8 48/31/40/-4/T/T/0.0/421/70 37 WNW AERO 37 MPH WNW RMY 39 11/9 44/29/37/-7/0.00/0.0/366/61 25 WNW AERO 25 MPH WNW RMY 29 11/10 52/40/46/+2/0.08/0.0/108/18 31 WNW AERO 33 MPH WNW RMY N/A 11/11 51/36/44/+1/0.00/0.0/.../.. 36 WNW AERO 37 MPH WNW RMY 37 11/12 48/24/36/-7/0.11/0.2/000/00 42 SW AERO 43 MPH SW RMY 43 11/13 35/21/28/-15/0.00/0.0/.../.. 29 NW AERO 30 MPH NW RMY 30 11/14 49/26/38/-4/0.00/0.0/.../.. 25 SW AERO 25 MPH SW RMY 28 11/15 morning low temp: 38F; the normal low is now 34F DAILY RECORDS FOR NOVEMBER 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR NOVEMBER 15 HIGH 74 IN 1993 LOW 15 IN 1933 PRECIP 1.66 INCHES IN 1981 SNOWFALL 4.0 IN 1967 PEAK GUST 65 SSE IN 2008 RECORDS FOR NOVEMBER 16 HIGH 73 IN 1927 LOW 8 IN 1933 PRECIP 2.25 INCHES IN 1981 SNOWFALL 2.0 IN 1913 PEAK GUST 78 S IN 1989 TODAY'S REPORT PREPARED BY: Sean Fankhauser