BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, APRIL 23, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME Today's weather observations: 7 A.M. Weather: Broken altocumulus, distant stratocumulus all quadrants except N-NE, few altocumulus lenticularis N-NE, virga E-S Temperature: 43F, Dew point: 34F, Wind: WSW at 14G22 kts, Wind: Direction variability S-W Sea-level pressure: 29.69 inches Hg, rising Visibility: 60 miles 6-hour minimum temperature: 40F 24-hour rainfall: 0.17 inch 6-hour rainfall: trace BHO SA 1155 E90 BKN 60 053/43/34/2414G22/969/ DSNT SC ALQDS XCPT N-NE FEW ACSL NW VIRGA E-S WND 18V28/ 8/540 51025 MANUAL 6000/ MANUAL 70017 ASOS 70014 10044 20040 10 A.M. Weather: Broken stratocumuls, broken altocumulus Temperature: 49F, Dew point: 33F, Wind: WSW at 18G32 kts, Wind: Peak gust 34 kts W at 9:27 A.M. Wind: Direction variable SSW to WNW Sea-level pressure: 29.73 inches Hg, rising Visibility: 75 miles BHO SA 1455 E40 BKN 100 BKN 75 069/49/33/2418G32/973/ PK WND 2634/27 WND 21V29/ 8/530 51016 1 P.M. Weather: Broken stratocumulus, broken altocumulus, virga NW-NE Temperature: 54F, Dew point: 34F, Wind: WSW at 18G28 kts, Wind: Peak gust 32 kts WSW at 12:00 noon Sea-level pressure: 29.75 inches Hg, rising Visibility: 80 miles 6-hourly max. temp: 55F BHO SA 1755 E55 BKN 70 BKN 140 BKN 80 074/54/34/2518G28/975/ VIRGA NW-NE PK WND 2432/1700 WND 19V31/ 8/830 53007 10055 20042 WEATHER SUMMARY FOR WEDNESDAY, APRIL 22, 2009 TEMPERATURE (DEGREES F) MAX.....62 NORMAL......58 MIN.....45 NORMAL......39 MEAN....54 NORMAL......49 DEPARTURE FROM 30-YEAR NORMAL..................+5 TOTAL DEPARTURE FOR THE MONTH.................+18 [+0.6 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............11 DEPARTURE........-5 TOTAL HEATING UNITS FOR THE MONTH............425 DEPARTURE.......-18 TOTAL HEATING UNITS FOR THE SEASON..........5843 DEPARTURE.......-64 TOTAL HEATING UNITS LAST SEASON TO DATE.....5515 DIFFERENCE.....+328 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............28 S AT 1:53 A.M. * AEROVANE.............24 S AT 1:20 A.M. ASOS.................28 SSW AT 1:53 A.M. DAVIS................29 S AT 1:38 A.M. FASTEST MILE FOR YESTERDAY..............21 S AT 1:40 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........22 SSW AT 1:40 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........22 S AT 1:39 A.M. AVERAGE..............11.2 S ASOS.................10.7 DAVIS................10.6 SSW [207 deg] * last of several occurrences... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.17 DEPARTURE.........+0.03 ASOS...............0.14 TOTAL PRECIPITATION FOR THE MONTH...........4.53 DEPARTURE.........+1.29 ASOS...............4.55 TOTAL PRECIPITATION FOR THE YEAR...........14.61 DEPARTURE.........-2.26 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.........-2.1 TOTAL SNOWFALL FOR THE SEASON..............78.9 DEPARTURE........+19.7 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 morning low temp: 40F, our normal low is now 39F 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 23 HIGH 85 IN 1908, 2007 LOW 25 IN 1933,1989 PRECIP 1.51 IN. IN 1998 SNOWFALL 0.5 IN. IN 1911, 1956 PEAK GUST 64 MPH WNW IN 1962 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 TODAY'S REPORT PREPARED BY: Stephanie Radner