BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, MAY 29, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME Today's observations: 7 A.M. Weather: Obscurement with fog Temperature: 51F, Dew point: 51F, Wind: NE at 8 kts Sea-level pressure: 29.81 inches Hg, falling Visibility: 1/16 mile, fog 6-hour minimum temp: 48F 24-hour precipitation: 0.04 in. BHO SA 1155 W2 X 1/16F 095/51/51/0508/981/ 8//// 58009 MANUAL 6001/ ASOS 60002 MANUAL 70004 ASOS 70005 10051 20048 10 A.M. Weather: Obscurement with fog Temperature: 54F, Dew point: 54F, Wind: ESE at 2 kts (estimated) Wind: Light and variable Sea-level pressure: 29.78 inches Hg, falling Visibility: 1/16 mile, fog 3-hourly rainfall: 0.03 in. BHO SA 1455 W2 X 1/16R-F 084/54/54/E1102/978/ WND L/V RBXX/ 8//// 56011 MANUAL 6003/ ASOS 60002 1 P.M. Weather: Overcast stratus Temperature: 56F, Dew point: 55F, Wind: W at 3 kts, Wind: Light and variable Sea-level pressure: 29.75 inches Hg, falling Visibility: 1 mile, fog 6-hour rainfall: 0.05 in. 6-hour maximum temp: 56F BHO SA 1755 E3 OVC 1F 076/56/55/2803/975/ WND L/V/ 8/6// 58008 MANUAL 6005/ ASOS 60005 10056 20051 WEATHER SUMMARY FOR THURSDAY, MAY 28 TEMPERATURE (DEGREES F) MAX.....48 NORMAL.....71 MIN.....45 NORMAL.....51 MEAN....47 NORMAL.....61 DEPARTURE FROM 30-YEAR NORMAL..........-14 TOTAL DEPARTURE FOR THE MONTH..........+42 [+1.3 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............18 DEPARTURE......+12 TOTAL HEATING UNITS FOR THE MONTH...........213 DEPARTURE......-44 TOTAL HEATING UNITS FOR THE SEASON.........6109 DEPARTURE.....-173 TOTAL HEATING UNITS LAST SEASON TO DATE....5894 DIFFERENCE....+215 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............28 NE AT 10:42 A.M. * AEROVANE..............25 NNE AT 7:14 A.M. ASOS..................25 ENE AT 10:42 A.M. DAVIS.................25 NE AT 10:42 A.M. FASTEST MILE FOR YESTERDAY...............16 N AT 2:11 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE............17 ENE AT 11:30 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........18 NE AT 11:30 A.M. AVERAGE WIND SPEED AND DIRECTION.........10.7 NNE ASOS..................10.8 DAVIS.................10.4 NE [035 DEG] * last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.04 DEPARTURE....-0.08 ASOS..............0.05 TOTAL PRECIPITATION FOR THE MONTH..........3.65 DEPARTURE....+0.24 ASOS..............3.64 TOTAL PRECIPITATION FOR THE YEAR..........18.26 DEPARTURE....-3.10 ASOS.............19.32 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/-8/0/601/67 28 NNE 5/27 52/43/48/-13/0.16/000/00 23 E AERO 19 MPH E 5/28 48/45/47/-14/0.03/000/00 28 NE AERO 25 MPH NNE 5/29 our morning low temp: 48F; 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 29 HIGH 93F IN 1919 LOW 35F IN 1902 PRECIP 1.63 INS 1990 PEAK GUST 55e MPH NNW IN 1943, WNW IN 1945 RECORDS FOR MAY 30 HIGH 93F IN 1929 LOW 39F IN 1949,1961 PRECIP 1.47 INS 1948 PEAK GUST 61e MPH NW IN 1945 TODAY'S REPORT PREPARED BY: Stephanie Radner