BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SUNDAY, MAY 18, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED Today's observations: 8 A.M. EDT Weather: Scattered cirrus Temperature: 57F, Dew point: 43F, Wind: W at 16G20 kt Sea-level pressure: 29.45 inches Hg, rising Visibility: 35 miles BHO SA 1155 250 SCT 35 973/57/43/2616G20/945/ 8/001 51014 70001 10057 20053 11 A.M. EDT Weather: Scattered cirrus Temperature: 64F, Dew point: 36F, Wind: SSW at 13G18 kt Sea-level pressure: 29.43 inches Hg, falling Visibility: 40 miles BHO SA 1455 250 SCT 40 967/64/36/2013G18/943/ WND BACKING/ 8/001 58006 2 P.M. EDT Weather: Overcast Temperature: 70F, Dew point: 37F, Wind: S at 11G14 kt Sea-level pressure: 29.40 inches Hg, falling Visibility: 40 miles BHO SA 1755 150 OVC 40 956/70/34/1911G14/940/ FEW BINOVC DSNT E WND BACKING/ 8/07/ 58011 10071 20057 WEATHER SUMMARY FOR SATURDAY, MAY 17 TEMPERATURE (DEGREES F) MAX.....72 NORMAL.....68 MIN.....46 NORMAL.....47 MEAN....59 NORMAL.....57 DEPARTURE FROM 30-YEAR NORMAL............+2 TOTAL DEPARTURE FOR THE MONTH...........-34 [-1.8 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............6 DEPARTURE........-2 TOTAL HEATING UNITS FOR THE MONTH...........209 DEPARTURE.......+27 TOTAL HEATING UNITS FOR THE SEASON.........5820 DEPARTURE......-388 TOTAL HEATING UNITS LAST SEASON TO DATE....5754 DIFFERENCE......+66 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............33 W AT 2:39 P.M. AEROVANE.............32 W AT 2:40 P.M. ASOS.................32 W AT 2:40 P.M. DAVIS................33 W AT 2:41 P.M. FASTEST MILE FOR YESTERDAY..............25 WNW AT 11:13 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........33 W AT 9:42 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........25 WNW AT 11:14 A.M. AVERAGE............11.9 NW ASOS...............11.3 DAVIS..............11.9 WNW [299 deg] * Last of several occurrences.... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...TRACE DEPARTURE......-0.12 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.63 DEPARTURE......-0.46 ASOS..............1.56 TOTAL PRECIPITATION FOR THE YEAR..........22.39 DEPARTURE......+2.35 ASOS.............24.79 # # Includes erroneous ASOS precipitation data on 2/13/08. PRELIMINARY CLIMATE SUMMARY FOR MAY 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available, records not finalized 5/1 60/35/48/-4/0/786/93 30 W Aero 28 MPH W 5/2 48/42/45/-7/0.07/000/00 21 ENE 5/3 43/41/42/-11/0.09/000/00 25 E 5/4 50/42/46/-7/0.17/000/00 27 E 5/5 69/40/55/+2/0/752/88 24 ESE 5/6 74/46/60/+6/0/686/80 25 W 5/7 75/48/62/+8/0/722/84 29 S 5/8 75/54/65/+11/0.08/172/20 42 W Aero 42 MPH W 5/9 56/43/50/-5/0.26/000/00 30 NE 5/10 57/44/51/-4/T/407/47 35 NNE 5/11 58/41/50/-5/0/747/86 24 ENE 5/12 47/42/45/-11/0/017/02 43 NNE Aero 43 MPH NNE 5/13 63/43/53/-3/0/812/93 47 NNE Aero 50 MPH NNE 5/14 64/47/56/-1/0/788/90 23 ENE 5/15 67/47/57/0/T/009/01 22 S 5/16 59/45/52/-5/.../.../.. 21 ENE 5/17 72/46/59/+2/.../.../.. 33 W NEW DAILY RECORDS FOR MAY 2008 None to date. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 18 HIGH 88F IN 1906, 1936, 1986 LOW 35F IN 2002 PRECIP 1.93 INCHES IN 2007 SNOW TRACE IN 2002 (Ice pellets) PEAK GUST 64 MPH SSW IN 2000 RECORDS FOR MAY 19 HIGH 91F IN 1962 LOW 34F IN 2002 PRECIP 1.54 INCHES IN 1900 PEAK GUST 58 MPH NW IN 1964 TODAY'S REPORT PREPARED By: Andrew Hoell