BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 15, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED Today's observations: 8 A.M. EDT Weather: Overcast altocumulus/altostratus, break in overcast N-E, bright spots NE-SE Temperature: 52F, Dew point: 30F, Wind: SSW at 11 kts Sea-level pressure: 29.98 inches Hg, rising Visibility: 50 miles 6-hour min temp: 47F BHO SA 1155 E110 OVC 50 154/52/30/2111/998/ BINOVC N-E BRGHT SPTS NE-SE DRK K LYR N-NE/ 8/07/ 53004 10052 20047 11 A.M. EDT Weather: Overcast altocumulus/altostratus, very light rain Temperature: 59F, Dew point: 32F, Wind: S at 10 kts Sea-level pressure: 29.98 inches Hg, falling Visibility: 45 miles 3-hour precip: Trace BHO SA 1455 E90 OVC 45R- 151/59/32/1810/998/ BINOVC N RB35E55 PCPN VRY LGT/ 8/07/ 58003 MANUAL 6000/ 2 P.M. EDT Weather: Overcast altocumulus/altostratus, small breaks Temperature: 66F, Dew point: 39F, Wind: SSE at 7 kts Sea-level pressure: 29.93 inches Hg, falling Visibility: 40 miles, hazy 6-hour max temp: 66F 6-hour precip: Trace BHO SA 1755 E70 OVC 40 135/66/39/1607/993/ NMRS SML BINOVC HAZY/ 8/07/ 56016 MANUAL 6000/ 10066 20052 WEATHER SUMMARY FOR WEDNESDAY, MAY 14 TEMPERATURE (DEGREES F) MAX.....64 NORMAL.....67 MIN.....47 NORMAL.....46 MEAN....56 NORMAL.....57 DEPARTURE FROM 30-YEAR NORMAL............-1 TOTAL DEPARTURE FOR THE MONTH...........-31 [-2.4 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............9 DEPARTURE.........0 TOTAL HEATING UNITS FOR THE MONTH...........182 DEPARTURE.......+26 TOTAL HEATING UNITS FOR THE SEASON.........5793 DEPARTURE......-389 TOTAL HEATING UNITS LAST SEASON TO DATE....5725 DIFFERENCE......+68 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............23 ENE AT 1:22 P.M. AEROVANE.............21 ENE AT 1:33 P.M. * ASOS.................23 E AT 1:22 P.M. DAVIS................22 ENE AT 1:22 P.M. FASTEST MILE FOR YESTERDAY..............18 ENE AT 1:24 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........17 ENE AT 1:26 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........18 ENE AT 1:22 P.M. AVERAGE............9.2 NNE ASOS...............9.4 DAVIS..............9.2 ENE [072 deg] * last of several occurrences... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE......-0.12 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.67 DEPARTURE......-1.06 ASOS..............0.62 TOTAL PRECIPITATION FOR THE YEAR..........21.43 DEPARTURE......+1.75 ASOS.............23.85 # # 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/.../.. 23 ENE 5/15 morning low temp. 47F; our normal low is now 47F 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 15 HIGH 93F IN 1900 LOW 36F IN 1947,1985 PRECIP 1.63 INCHES IN 1978 PEAK GUST 53e MPH NE IN 1978, W 2002 RECORDS FOR MAY 16 HIGH 90F IN 1951 LOW 30F IN 1936 PRECIP 2.63 INCHES IN 1954 PEAK GUST 56e MPH NW IN 1952 TODAY'S REPORT PREPARED By: Stephanie Radner