BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, MAY 2, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED Today's observations: 8 A.M. EDT Weather: Overcast, light rain Temperature: 45F, Dew point: 44F, Wind: SE at 2 kts Sea-level pressure: 30.16 inches Hg, falling Visibility: 5 miles, variable 2-8 miles, fog 6-hour min temp: 44F 6-hour precip: 0.03 in. 24-hour precip: 0.03 in. BHO SA 1155 E40 OVC 5VR-F 213/45/44/E1302/016/ FEW LWR STRA VSBY 2V8 PCPN VRY LGT/ 8/72/ 53009 MANUAL 6003/ ASOS 60003 MANUAL 70003 ASOS 70003 10045 20044 11 A.M. EDT Weather: Overcast, light rain Temperature: 47F, Dew point: 46F, Wind: ENE at 6 kts Sea-level pressure: 30.15 inches Hg, falling Visibility: 6 miles, variable 5-8 miles, fog 3-hour precip: trace BHO SA 1455 E40 OVC 6VR-F 211/47/46/0706/015/ FEW LWR STRA VSBY 5V8 PCPN VRY LGT/ 8/72/ 58002 MANUAL 6000/ 2 P.M. EDT Weather: Overcast Temperature: 48F, Dew point: 46F, Wind: ENE at 8 kts Sea-level pressure: 30.14 inches Hg, falling Visibility: 3 miles, fog 6-hour max. temp: 48F 6-hour precip: trace BHO SA 1755 E10 OVC 3F 205/48/46/0608/014/ 8/7// 58006 MANUAL 6000/ 10048 20045 WEATHER SUMMARY FOR THURSDAY, MAY 1 TEMPERATURE (DEGREES F) MAX.....60 NORMAL.....62 MIN.....35 NORMAL.....42 MEAN....48 NORMAL.....52 DEPARTURE FROM 30-YEAR NORMAL............-4 TOTAL DEPARTURE FOR THE MONTH............-4 [-4.5 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............17 DEPARTURE........+4 TOTAL HEATING UNITS FOR THE MONTH............17 DEPARTURE........+4 TOTAL HEATING UNITS FOR THE SEASON.........5628 DEPARTURE......-411 TOTAL HEATING UNITS LAST SEASON TO DATE....5625 DIFFERENCE.......+3 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............30 W AT 11:43 A.M. AEROVANE.............28 W AT 11:43 A.M. ASOS.................28 W AT 11:43 A.M. DAVIS................30 W AT 11:43 A.M. FASTEST MILE FOR YESTERDAY..............16 W AT 3:12 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE...........17 WNW AT 3:13 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........19 W AT 3:13 P.M. AVERAGE.............9.0 W ASOS................8.7 DAVIS...............9.4 W [264 deg] * last of several occurrences. 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 THE MONTH..........0.03 DEPARTURE......-0.10 ASOS..............0.03 TOTAL PRECIPITATION FOR THE YEAR..........20.79 DEPARTURE......+2.71 ASOS.............23.26 # # Includes erroneous ASOS precipitation data on 2/13/08. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE......-0.1 TOTAL SNOWFALL FOR THE MONTH...............0.0 DEPARTURE......-0.1 TOTAL SNOWFALL FOR THE SEASON.............66.5 DEPARTURE......+6.4 ** ** corrected error of 0.1 in snowfall departure for the season; this error was introduced in late March or early April PRELIMINARY CLIMATE SUMMARY FOR APRIL 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available, records not finalized 4/1 59/50/55/+14/0.20/0/000/00 54 S Aero 58 MPH SSW 4/2 47/31/39/-3/0/0/745/97 52 W Aero 51 MPH W 4/3 52/27/40/-2/0/0/648/84 37 SSW 4/4 43/34/39/-3/0.71/0/000/00 35 E 4/5 51/37/44/+1/0.06/0/093/12 21 W 4/6 40/36/38/-5/0.09/0/000/00 36 NE 4/7 39/34/37/-6/0/0/172/22 35 NE Aero 36 MPH NE 4/8 47/30/39/-5/0/0/627/80 22 NE 4/9 59/33/47/+3/0/0/150/19 29 S 4/10 71/44/58/+14/T/0/624/79 34 W 4/11 54/40/47/+2/0.03/096/13 24 SE 4/12 70/43/57/+12/0.43/0/342/43 40 WNW Aero 42 WNW 4/13 47/34/41/-4/T/0/104/13 30 NW 4/14 53/30/42/-4/0/0/625/78 29 NW 4/15 57/33/45/-1/0/0/803/100 23 SSE 4/16 64/39/52/+6/0/0/806/100 24 SSE 4/17 64/14/53/+6/0/0/810/100 23 NE 4/18 70/42/56/+9/0/0/723/89 23 NW 4/19 70/46/58/+11/0/0/799/98 22 NE 4/20 67/42/55/+7/0/0/760/93 25 ESE 4/21 61/41/51/+3/0/0/615/75 17 E 4/22 74/45/60/+11/0/0/789/96 23 S 4/23 83/50/67/+18/0/0/784/95 25 SW 4/24 72/53/63/+14/0/0/802/97 38 WNW Aero 39 WNW 4/25 71/46/59/+9/0/0/557/67 25 E 4/26 55/42/49/-1/T/0/716/86 27 ENE 4/27 49/40/45/-5/0.02/0/000/00 16 ESE 4/28 57/39/48/-3/0.67/0/008/01 39 SE Aero 39 SE 4/29 60/39/50/-1/0.95/0/008/01 44 WNW Aero 44 WNW 4/30 54/35/45/-7/0/0/700/83 29 WSW PRELIMINARY CLIMATE SUMMARY FOR MAY 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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/-4/0/0/.../.. 30 W Aero 28 W 5/2 morning low temp. 44F; our normal low is now 43F 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 2 HIGH 92F IN 2001 LOW 29F IN 1903 PRECIP 1.36 INCHES IN 2006 SNOWFALL 1.0 INS IN 1888 PEAK GUST 58 MPH S IN 1983 RECORDS FOR MAY 3 HIGH 92F IN 2001 LOW 31F IN 1888 PRECIP 2.25 INS IN 1900 SNOWFALL TRACE IN 1908, 1985 PEAK GUST 71 MPH W IN 2002 TODAY'S REPORT PREPARED By: Stephanie Radner