BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, JUNE 1, 2007 ALL TIMES ARE IN EASTERN STANDARD TIME MAY 2007 MONTHLY STATISTICS Temps: deg. F Mean temp: 59.5 [+2.5] 24-hour corrected mean: 58.8 Av. Max. 69.9 Av. Min. 49.0 Max: 91/25th Min: 39/7th HDD: 215 [- 56] CDD: 53 [+ 32] Precip: 3.74 [-0.05 in.] Av. uncorrected wind speed: 11.5 mph Av. corr. wind speed: 11.9 mph Prevailing direction: S 15% Peak wind gust: 40 mph NW on 16th Peak gust Maximum, Inc. 46 WNW on 4th Total sunshine (astronomical minutes) 17044 OR 63% Today's observations: 7 A.M. Weather: Scattered clouds (altocumulus) Temperature: 60F, Dew point: 55F, Wind: SSW at 09 kts Sea-level pressure: 30.04 inches Hg, steady Visibility: 15 miles, hazy 6-hour min temp. 56F TSTM ended 2-3 hours ago BHO SA 1155 150 SCT 15 171/60/55/2109/004/ HAZY/ 8/030 56006 MANUAL 70003 ASOS 70003 10060 20056 10 A.M. Weather: High thin broken cirrus, hazy Temperature: 75F, Dew point: 61F, Wind: SW at 08 kts Sea-level pressure: 29.99 inches Hg, falling Visibility: 15 miles, hazy BHO SA 1455 300 –BKN 15 155/75/61/2308/999/ HAZY/ 8/001 57016 1 P.M. Weather: Scattered clouds, cumulus and cirrus, few modt. cumulus Temperature: 85F, Dew point: 65F, Wind: SSW at 08 kts Wind: direction south variable WSW Sea-level pressure: 29.93 inches Hg, falling Visibility: 10 miles, hazy 6-hour max. temp. 86 deg. BHO SA 1755 55 SCT 250 SCT 300 SCT 10 136/85/65/2108/993/ MDT CU HAZY WND 18V24 GST 20 KTS PST HR/ 8/201 10086 20060 WEATHER SUMMARY FOR THURSDAY, MAY 31 TEMPERATURE (DEGREES F) MAX.....67 NORMAL.....72 MIN.....56 NORMAL.....52 MEAN....62 NORMAL.....62 DEPARTURE FROM 30-YEAR NORMAL............0 TOTAL DEPARTURE FOR THE MONTH..........+86 (+2.5 DEGREES/DAY) HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............3 DEPARTURE.........-2 TOTAL HEATING UNITS FOR THE MONTH..........215 DEPARTURE........-56 TOTAL HEATING UNITS FOR THE SEASON........5831 DEPARTURE.......-466 TOTAL HEATING UNITS LAST SEASON TO DATE...5714 DIFFERENCE......+117 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............23 NE AT 5:22 A.M. AEROVANE.............19 NE AT 5:57 A.M. ASOS.................21 NE AT 5:22 A.M. DAVIS................N/A FASTEST MILE FOR YESTERDAY..............13 NE AT 5:59 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........15 NE AT 5:57 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........N/A AVERAGE WIND SPEED AND DIRECTION........8.0 NE ASOS.................7.8 DAVIS................N/A PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.03 DEPARTURE.....-0.10 ASOS..............0.03 TOTAL PRECIPITATION FOR MAY................3.74 DEPARTURE.....-0.05 ASOS..............3.67 TOTAL PRECIPITATION FOR THE YEAR..........24.16 DEPARTURE.....+2.42 ASOS.............23.64 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/+5/0/0/413/46 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/+9/0/0/848/94 21 WSW 5/31 67/56/62/0/0.03/0/054/06 23 NE 6/1 morning low temp. 56 deg; normal low now 52 deg. early morning TSTM with no rain 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. 5/26 Record high minimum temperature, 66; previous 63 in 1981. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): 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 RECORDS FOR JUNE 2 HIGH 91F IN 1895 LOW 41F IN 1907, 1929 PRECIP 2.36 INS IN 1982 PEAK GUST 63 MPH NW IN 2000 TODAY'S REPORT PREPARED By: Robert Skilling