BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 28, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME Today's observations: 7 A.M. Weather: Obscurement with fog, light drizzle Temperature: 46F, Dew point: 46F, Wind: NNE at 10G22 kts, Wind: Direction variable SW to ENE Sea-level pressure: 30.00 inches Hg, rising Visibility: 1/8 mile, variable 1/16 to 1/4 mile 6-hour minimum temp: 45F 24-hour precipitation: 0.12 in. BHO SA 1155 W3 X 1/8VL-F 160/46/46/0310G22/000/ VSBY 1/16V1/4 WND 23V07 L-B50/ 8//// 53013 MANUAL 6000/ MANUAL 70012 ASOS 70011 10047 20045 10 A.M. Weather: Overcast stratus, light drizzle Temperature: 47F, Dew point: 47F, Wind: NE at 11G19 kts, Wind: Direction variable N to ENE Sea-level pressure: 30.01 inches Hg, rising Visibility: 1 mile, variable 1/2 to 1 1/2 miles, fog 3-hourly rainfall: trace BHO SA 1455 E3 OVC 1VL-F 163/47/47/0411G19/001/ VSBY 1/2V11/2 WND 35V07/ 8/6// 51003 MANUAL 6000/ 1 P.M. Weather: Overcast stratus, light drizzle Temperature: 48F, Dew point: 47F, Wind: NNE at 13G21 kts Wind: Direction variable NNW to ENE Sea-level pressure: 30.00 inches Hg, falling Visibility: 2 miles, fog 3-hour rainfall: trace 6-hour maximum temp: 48F BHO SA 1755 E3 OVC 2L-F 160/48/47/0313G21/000/ WND 33V07/ 8/6// 58003 MANUAL 6000/ ASOS 60001 10048 20046 WEATHER SUMMARY FOR WEDNESDAY, MAY 27 TEMPERATURE (DEGREES F) MAX.....52 NORMAL.....71 MIN.....43 NORMAL.....50 MEAN....48 NORMAL.....61 DEPARTURE FROM 30-YEAR NORMAL..........-13 TOTAL DEPARTURE FOR THE MONTH..........+56 [+1.9 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............17 DEPARTURE......+11 TOTAL HEATING UNITS FOR THE MONTH...........195 DEPARTURE......-56 TOTAL HEATING UNITS FOR THE SEASON.........6091 DEPARTURE.....-185 TOTAL HEATING UNITS LAST SEASON TO DATE....5886 DIFFERENCE....+205 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............23 E AT 7:57 A.M. AEROVANE..............19 E AT 7:57 A.M. ASOS..................21 ESE AT 7:57 A.M. DAVIS.................20 E AT 7:57 A.M. FASTEST MILE FOR YESTERDAY...............14 E AT 7:56 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE............15 ESE AT 7:58 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........15 E AT 7:58 A.M. AVERAGE WIND SPEED AND DIRECTION.........6.7 NNE ASOS..................6.4 DAVIS.................6.4 E [084 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.12 DEPARTURE........0 ASOS..............0.11 TOTAL PRECIPITATION FOR THE MONTH..........3.61 DEPARTURE....+0.32 ASOS..............3.59 TOTAL PRECIPITATION FOR THE YEAR..........18.22 DEPARTURE....-3.02 ASOS.............19.27 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..............78.9 DEPARTURE.....18.8 PRELIMINARY CLIMATE SUMMARY FOR MAY 2009 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system gust when significant TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 5/1 64/53/59/+7/T/000/00 37 SSW AERO 37 MPH SSW 5/2 68/52/60/+8/0.05/263/31 32 WNW 5/3 64/48/56/+3/T/068/08 25 S 5/4 64/48/56/+3/0.01/009/01 17 SSW 5/5 52/44/48/-5/0.95/000/00 43 NNE AERO 40 MPH NNE 5/6 63/43/53/-1/0.40/189/22 24 SSE 5/7 68/49/59/+5/0.60/009/01 29 S 5/8 75/52/64/+10/0/690/80 28 S 5/9 71/55/63/+8/0.14/104/12 31 W TSTM 5/10 65/46/56/+1/0/840/97 53 W Aero 50 MPH W 5/11 63/41/52/-3/0/781/90 24 WNW 5/12 63/45/54/-2/0/696/80 22 ENE 5/13 70/45/58/+2/0/732/84 31 SSE AERO 29 MPH SSE 5/14 62/47/55/-2/0.10/166/19 53 S AERO 52 MPH S 5/15 76/54/65/+8/0/474/54 38 S AERO 38 MPH S 5/16 68/54/61/+4/T/457/52 35 S AERO 35 MPH S 5/17 61/49/55/-2/0.09/009/01 35 WNW AERO 33 MPH WNW 5/18 53/42/48/-10/0.04/168/19 27 NE 5/19 70/42/56/-2/0/813/92 28 S 5/20 82/49/66/+8/0/771/87 31 SSW 5/21 89/59/74/+15/0/870/98 37 S AERO 34 MPH S 5/22 87/59/73/+14/0/739/83 31 N 5/23 65/50/58/-1/T/428/48 28 NE 5/24 80/50/65/+5/1.07/536/60 25 WNW TSTM TRACE DIME SIZE HAIL 5/25 76/51/64/+4/0/868/97 32 N 5/26 58/46/52/-8/0/.../.. 28 NNE 5/27 52/43/48/-13/0.16/000/00 23 E AERO 19 MPH E 5/28 our morning low temp: 45F; the normal low is now 51F NEW DAILY RECORDS FOR MAY 2009... 5/14: RECORD PEAK WIND GUST 53 MPH S; surpasses previous record of 50 MPH SW in 1976 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 28 HIGH 90F IN 1929 LOW 39F IN 1917 PRECIP 2.48 INS 1906 PEAK GUST 51e MPH NE IN 1946 RECORDS FOR MAY 29 HIGH 93F IN 1919 LOW 35F IN 1902 PRECIP 1.63 INS 1990 PEAK GUST 55e MPH NNW IN 1943, WNW IN 1945 TODAY'S REPORT PREPARED BY: Stephanie Radner