BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, APRIL 24, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME Today's weather observations: 7 A.M. Weather: Clear, few cirrus NW, smoke layer SW-NW Temperature: 46F, Dew point: 35F, Wind: W at 12G19 kts, Wind: Direction variability SW to NNW Sea-level pressure: 30.22 inches Hg, rising Visibility: 30 miles, light haze 6-hour minimum temperature: 40F BHO SA 1155 CLR 30 232/46/35/2712G19/022/ FEW CI NW K LYR SW-NW LGT HZ WND 23V34/ 8/001 53029 10046 20040 10 A.M. Weather: Clear, few cirrus Temperature: 58F, Dew point: 32F, Wind: W at 10 kts, Wind: Direction variability SSW to NW Sea-level pressure: 30.23 inches Hg, rising Visibility: 60 miles BHO SA 1455 CLR 60 236/58/32/2710/023/ FEW CI ALQDS XCPT E-S WND 21V32/ 8/001 51004 1 P.M. Weather: Thin scattered cirrus Temperature: 64F, Dew point: 32F, Wind: SW at 9 kts Sea-level pressure: 30.22 inches Hg, falling Visibility: 70 miles 6-hourly max. temp: 65F BHO SA 1755 250 -SCT 70 235/64/32/2309/022/ 8/001 55001 10065 20046 WEATHER SUMMARY FOR THURSDAY, APRIL 23, 2009 TEMPERATURE (DEGREES F) MAX.....56 NORMAL......58 MIN.....40 NORMAL......39 MEAN....48 NORMAL......49 DEPARTURE FROM 30-YEAR NORMAL..................-1 TOTAL DEPARTURE FOR THE MONTH.................+17 [+0.5 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............17 DEPARTURE........+1 TOTAL HEATING UNITS FOR THE MONTH............442 DEPARTURE.......-17 TOTAL HEATING UNITS FOR THE SEASON..........5860 DEPARTURE.......-63 TOTAL HEATING UNITS LAST SEASON TO DATE.....5515 DIFFERENCE.....+345 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............43 W AT 1:36 P.M. AEROVANE.............42 W AT 1:36 P.M. ASOS.................43 WNW AT 1:36 P.M. DAVIS................45 W AT 1:13 P.M. FASTEST MILE FOR YESTERDAY..............34 WSW AT 1:19 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE...........33 W AT 1:19 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........33 W AT 1:19 P.M. AVERAGE..............19.5 WSW ASOS.................17.5 DAVIS................18.1 WSW [253 deg] * last of several occurrences... 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...........4.53 DEPARTURE.........+1.15 ASOS...............4.55 TOTAL PRECIPITATION FOR THE YEAR...........14.61 DEPARTURE.........-2.40 ASOS..............15.68 # # Includes erroneous ASOS precipitation data on 1/1/09, 1/2/09 and 2/27/09. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE.........-0.1 TOTAL SNOWFALL FOR THE MONTH................0.2 DEPARTURE.........-2.2 TOTAL SNOWFALL FOR THE SEASON..............78.9 DEPARTURE........+19.6 PRELIMINARY CLIMATE SUMMARY FOR APRIL 2009 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system gust when significant TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 4/1 43/31/38/-3/0.13/0/015/02 24 SE 4/2 52/39/46/+4/0.02/0/000/00 20 SSE 4/3 58/45/52/+10/0.70//000/00 39 SSE AERO 38 MPH SSE TSTM 4/4 51/38/45/+3/0.01/0/015/02 48 WSW AERO 48 MPH WSW 4/5 58/37/48/+5/0/0/551/71 40 W AERO 37 MPH W 4/6 55/38/47/+4/1.42/0/047/006 42 SE AERO 40 MPH SE TSTM 4/7 50/34/42/-1/T/0/109/14 36 WSW AERO 35 MPH WSW 4/8 45/32/39/-5/0/0/149/19 33 SW AERO 31 MPH SW 4/9 60/34/47/+3/0/0/692/88 36 SSW AERO 33 MPH SSW 4/10 65/41/53/+9/0.18/0/544/69 37 SSW AERO 35 MPH SSW 4/11 44/33/39/-6/0.77/0.2/000/00 35 N AERO 30 MPH N 4/12 43/29/36/-9/0/0/541/68 45 NW AERO 43 MPH WNW 4/13 52/29/41/-4/0/0/734/92 38 W AERO 35 MPH W 4/14 58/37/48/+2/0/0/696/87 25 E 4/15 49/36/43/-3/0/0/650/81 35 NE AERO 31 MPH NE 4/16 50/34/42/-4/0/0/806/100 29 NNE 4/17 69/35/52/+5/0/0/695/86 37 W AERO 33 MPH W 4/18 64/44/54/+7/0.05/0/170/21 28 W 4/19 52/38/45/-2/0.03/0/773/95 33 NNE AERO 28 MPH NNE 4/20 51/36/44/-4/0.07/0/.../... 43 E AERO 39 MPH E 4/21 58/42/50/+2/0.95/0/000/00 43 E AERO 43 MPH S 4/22 62/45/54/+5/0.16/0/.../.. 28 S AERO 24 MPH S 4/23 56/40/48/-1/0.01/0/.../.. 43 W 4/24 morning low temp: 40F, our normal low is now 40F NEW DAILY RECORDS FOR APRIL 2009... None to date.. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 24 HIGH 82 IN 2001 LOW 22 IN 1930 PRECIP 2.51 INS IN 1898 SNOWFALL 1.2 INS IN 1967 PEAK GUST 59 MPH NW IN 1962 RECORDS FOR APRIL 25 HIGH 80 IN 1942 LOW 24 IN 1892 PRECIP 1.38 IN. IN 1901 SNOWFALL 0.7 IN. IN 2002. PEAK GUST 66 MPH SE IN 1968 TODAY'S REPORT PREPARED BY: Stephanie Radner