BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, APRIL 18, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED Today's observations: 8 A.M. EDT Weather: Scattered altocumulus, cirrus Temperature: 48F, Dew point: 20F Wind: NW at 13 kts Sea-level pressure: 30.00 inches Hg, rising Visibility: 55 miles 6-hour min temp: 40F 24-hour precipitation: none BHO SA 1155 130 SCT 250 SCT 55 160/48/20/3213/000/ 8/031 53009 10048 20040 11 A.M. EDT Weather: Thin scattered cirrus Temperature: 66F, Dew point: 21F, Wind: NNE at 6 kts Wind: Light and variable Sea-level pressure: 30.01 inches Hg, rising Visibility: 35 miles, light haze BHO SA 1455 250 -SCT 35 163/66/21/0206/001/ FEW CI VERTBRTS LGT HZ WND L/V/ 8/001 50003 2 P.M. EDT Weather: Clear, few cirrus E-S Temperature: 67F, Dew point: 20F, Wind: NNE at 10 kts Sea-level pressure: 29.99 inches Hg, falling Visibility: 40 miles, light haze 6-hourly max.temp: 69F BHO SA 1755 CLR 40 157/67/20/0310/999/ FEW CI E-S LGT HZ/ 8/001 56006 10069 20048 WEATHER SUMMARY FOR THURSDAY, APRIL 17 TEMPERATURE (DEGREES F) MAX.....64 NORMAL.....56 MIN.....41 NORMAL.....38 MEAN....53 NORMAL.....47 DEPARTURE FROM 30-YEAR NORMAL...........+6 TOTAL DEPARTURE FOR THE MONTH..........+24 [+1.2 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............12 DEPARTURE....... -6 TOTAL HEATING UNITS FOR THE MONTH...........333 DEPARTURE.......-24 TOTAL HEATING UNITS FOR THE SEASON.........5470 DEPARTURE......-351 TOTAL HEATING UNITS LAST SEASON TO DATE....5454 DIFFERENCE......+16 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............23 NE AT 1:13 P.M. AEROVANE.............23 NE AT 1:19 P.M. ASOS.................23 E AT 1:15 P.M. DAVIS................22 ENE AT 1:13 P.M. FASTEST MILE FOR YESTERDAY............. 17 NE AT 1:13 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........18 ENE AT 1:14 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........18 NE AT 1:14 P.M. AVERAGE WIND SPEED AND DIRECTION.......8.9 NNE ASOS................8.9 DAVIS...............8.9 NNE [029 deg] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE......-0.14 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.52 DEPARTURE......-1.02 ASOS..............1.66 TOTAL PRECIPITATION FOR THE YEAR..........19.12 DEPARTURE......+2.95 ASOS.............21.54 # # Includes erroneous ASOS precipitation data on 2/13/08. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE......-0.1 TOTAL SNOWFALL FOR APRIL...................0.0 DEPARTURE......-1.8 TOTAL SNOWFALL FOR THE SEASON.............66.5 DEPARTURE......+7.7 PRELIMINARY CLIMATE SUMMARY FOR APRIL 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available, records not finalized 4/1 59/50/55/+14/0.20/0/000/00 54 S Aero 58 MPH SSW 4/2 47/31/39/-3/0/0/745/97 52 W Aero 51 MPH W 4/3 52/27/40/-2/0/0/648/84 37 SSW 4/4 43/34/39/-3/0.71/0/000/00 35 E 4/5 51/37/44/+1/0.06/0/093/12 21 W 4/6 40/36/38/-5/0.09/0/000/00 36 NE 4/7 39/34/37/-6/0/0/172/22 35 NE Aero 36 MPH NE 4/8 47/30/39/-5/0/0/627/80 22 NE 4/9 59/33/47/+3/0/0/150/19 29 S 4/10 71/44/58/+14/T/0/624/79 34 W 4/11 54/40/47/+2/0.03/096/13 24 SE 4/12 70/43/57/+12/0.43/0/342/43 40 WNW Aero 42 WNW 4/13 47/34/41/-4/T/0/104/13 30 NW 4/14 53/30/42/-4/0/0/625/78 29 NW 4/15 57/33/45/-1/0/0/803/100 23 SSE 4/16 64/39/52/+6/0/0/806/100 24 SSE 4/17 64/14/53/+6/0/0/810/100 23 NE 4/18 morning low temp. 40F; our normal low is now 38F NEW DAILY RECORDS FOR APRIL 2008 None to date. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 18 HIGH 92 IN 1976 LOW 23 1887 PRECIP 1.48 IN 1954 SNOWFALL 3.7 IN. IN 1965 PEAK GUST 59 MPH S IN 1982 RECORDS FOR APRIL 19 HIGH 94 IN 1976 [RECORD FOR MONTH] LOW 21 IN 1890 PRECIP 1.71 IN 1969 SNOWFALL 6.0 IN. IN 1887 PEAK GUST 66 MPH E IN 1984 TODAY'S REPORT PREPARED By: Stephanie Radner