BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 31, 2007 ALL TIMES ARE IN EASTERN STANDARD TIME Today's observations: 7 A.M. Weather: Overcast with a rain shower Temperature: 57F, Dew point: 53F, Wind: NE at 10 kt Sea-level pressure: 30.16 inches Hg, rising Visibility: 15 miles 6-hour min temp. 57F BHO SA 1155 10 BKN 80 OVC 15RW- 215/57/53/0410/016/ RB45/ 8/4// 51013 6000/ 10062 20057 10 A.M. Weather: Overcast Temperature: 60F, Dew point: 57F, Wind: NE at 10 kt Sea-level pressure: 30.18 inches Hg, rising Visibility: 15 miles BHO SA 1455 15 BKN 80 OVC 15 220/60/57/0410/018/ 8/4// 53005 6002/ WEATHER SUMMARY FOR WEDNESDAY, MAY 30 TEMPERATURE (DEGREES F) MAX.....82 NORMAL.....71 MIN.....56 NORMAL.....51 MEAN....69 NORMAL.....61 DEPARTURE FROM 30-YEAR NORMAL..........+ 8 TOTAL DEPARTURE FOR THE MONTH..........+86 (+2.7 DEGREES/DAY) HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............0 DEPARTURE.........-5 TOTAL HEATING UNITS FOR THE MONTH..........212 DEPARTURE........-54 TOTAL HEATING UNITS FOR THE SEASON........5828 DEPARTURE.......-454 TOTAL HEATING UNITS LAST SEASON TO DATE...5714 DIFFERENCE......+114 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............21 WSW AT 4:28 P.M. AEROVANE.............17 WSW AT 4:28 P.M. ASOS.................18 W AT 4:30 P.M. DAVIS................21 SW AT 1:53 P.M. FASTEST MILE FOR YESTERDAY..............13 SW AT 9:18 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........14 W AT 4:30 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........16 SSW AT 9:17 P.M. AVERAGE WIND SPEED AND DIRECTION........8.3 NW ASOS.................8.0 DAVIS................8.3 W [263 deg] * LAST OF SEVERAL OCCURRENCES PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...TRACE DEPARTURE.....-0.13 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........3.71 DEPARTURE.....+0.05 ASOS..............3.64 TOTAL PRECIPITATION FOR THE YEAR..........24.13 DEPARTURE.....+2.52 ASOS.............23.61 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE.......0.0 TOTAL SNOWFALL FOR THE MONTH................0.0 DEPARTURE......-0.1 TOTAL SNOWFALL FOR THE SEASON..............27.6 DEPARTURE.....-32.5 PRELIMINARY CLIMATE SUMMARY FOR MAY 2007......CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available 5/1 67/44/56/+4/0/0/624/74 33 NW 5/2 64/45/55/+3/0.06/0/381/45 36 NW Aero 33 MPH WNW 5/3 67/42/55/+2/0/0/849/100 38 W Aero 37 MPH W 5/4 66/44/55/+2/0/0/842/99 39 WNW Aero 40 MPH WNW 5/5 65/45/55/+2/0/0/384/45 33 N 5/6 51/42/47/-7/T/0/514/60 36 N Aero 33 MPH N 5/7 68/39/54/0/0/0/798/93 25 S 5/8 77/43/60/+6/0/0/851/99 33 S Aero 31 MPH S 5/9 85/54/70/+15/0/0/707/92 30 S 5/10 85/60/73/+18/0/0/692/80 29 S Aero 27 MPH S 5/11 74/60/67/+12/0.02/0/355/41 23 S TSTM A.M. 5/12 63/47/55/-1/0.02/0/469/54 32 NE 5/13 65/46/56/0/T/0/775/89 33 WNW Aero 33 MPH WNW 5/14 73/43/58/+1/0/0/822/94 30 SSW 5/15 80/50/65/+8/0.01/0/210/24 30 S TSTM evening 5/16 66/44/55/-2/0.54/0/527/60 40 NW TSTM P.M. 5/17 50/42/46/-11/0.01/0/009/01 28 NE 5/18 42/39/41/-17/1.93/0/000/00 37 NNE 5/19 51/40/46/-12/0.71/0/000/00 25 NNW 5/20 59/49/54/-4/0.41/0/035/04 30 W TSTM P.M. 5/21 63/46/55/-4/0/0/693/78 29 WNW 5/22 71/46/59/0/0/0/800/90 25 SSE 5/23 74/47/61/0/0/757/85 30 SSE 5/24 86/50/68/+8/0/0/828/93 25 WSW 5/25 91/66/79/+19/0/0/769/86 24 W 5/26 85/66/76/+16/0/0/689/77 30 W 5/27 73/58/66/+5/0/0/.../.. 22 SSE 5/28 82/58/70/+9/T/0/476/53 33 WNW 5/29 76/53/65/+4/0/0/873/97 30 WNW 5/30 82/56/69/+9/0/0/.../.. 21 WSW NEW DAILY RECORDS FOR MAY: 5/18 Record low maximum temperature, 42; previous 48 in 1895 and 1956. 5/18 Record daily precipitation, 1.93; previous 1.58 inches in 2002. 5/25 Record high maximum temperature, 91; previous 89 in 1981. 5/25 Record high minimum temperature, 66; previous 65 in 1991. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 31 HIGH 92F IN 1944,1987 LOW 35F IN 1961 PRECIP 5.02 INCHES 1984 (RECORD FOR MAY) PEAK GUST 54e MPH WNW IN 1945 RECORDS FOR JUNE 1 HIGH 90F IN 1937 LOW 36F IN 1945 [Record for month] PRECIP 2.28 INCHES IN 1992 PEAK GUST 51e MPH SE IN 1952 TODAY'S REPORT PREPARED By: Andrew Hoell