BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA   DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, AUGUST 18, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME   SUMMER OF 2009 LOSES ITS COOL TO AUGUST HEAT WAVE OF THREE DAYS INCLUDING TODAY   High temperatures reached 90F (89.5) on Sunday and 91F (90.8) yesterday and then went to 91F by early afternoon today making an official three-day heat wave.  Developing cumulus clouds may cap today's high in the lower 90's or just short of the record 93F set on August 18, 2002.  Temperatures only dropped to 72F early this morning and this will likely be the highest minimum temperature of the summer to date. The last heat wave here at Blue Hill lasted four days during early June, 2008.   Today's observations:   7 A.M.   Weather: Partial obscurement with haze  obscuring one tenth of sky  Temperature: 76F, Dew point: 68F, Wind: SW at 9 kts Sea-level pressure: 30.07 inches Hg, falling Visibility: 5 miles, haze  6-hour minimum temp: 72F BHO SA 1155 –X 5H 183/76/68/2309/007/ H1/ 58001 10076 20072      10 A.M. Weather: Clear and hazy Temperature: 86F, Dew point: 70F, Wind: SSW at 5 kts Sea-level pressure:  30.05 inches Hg, falling Visibility: 9 miles BHO SA 1455 CLR 9 178/86/70/2005/005/ HAZY WND L/V/ 56005   1 P.M. Weather: Scattered cumulus including cumulus congestus and a few towering cumulus    Temperature: 90F, Dew point: 67F, Wind: SW at 12G21 kts, Wind: direction variable S to W  Sea-level pressure: 30.02 inches Hg, falling Visibility: 12 miles, hazy 6-hourly max. temp: 91F BHO SA 1755 50 SCT 12 167/90/67/2312G21/002/ MDT CU AND FEW TCU ALQDS HAZY WND 19V27/ 8/200 56011 10091 20076    WEATHER SUMMARY FOR MONDAY, AUGUST 17   TEMPERATURE (DEGREES F) MAX.....91    NORMAL.....79 MIN.....69    NORMAL.....61 MEAN....80    NORMAL.....70   DEPARTURE FROM 30-YEAR AVERAGE..........+10 TOTAL DEPARTURE FOR THE MONTH...........+21 [+1.0 DEGREE/DAY]   HEATING DEGREE DATA WILL RESUME IN SEPTEMBER   PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............21 WSW AY  1:39 P.M.                     AEROVANE..............18 WSW AT  1:40 P.M.                    ASOS..................20 WSW AT  1:40 P.M.                           DAVIS.................20 W   AT  1:45 P.M.    FASTEST MILE FOR YESTERDAY...............13 WSW AT  3:06 P.M.  MAXIMUM 2-MINUTE ASOS AVERAGE............14 WSW AT  3:03 P.M.         MAXIMUM 2-MINUTE DAVIS AVERAGE...........14 SSW AT  2:21 A.M.     AVERAGE WIND SPEED AND DIRECTION........9.0 WSW                    ASOS.................8.7                    DAVIS................8.5 SW [220 DEG] * last of several occurrences   PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00   DEPARTURE....-0.13                          ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.84   DEPARTURE....-1.34                          ASOS..............0.84 TOTAL PRECIPITATION FOR THE YEAR..........32.10   DEPARTURE....+0.51                          ASOS.............33.22   PRELIMINARY CLIMATE SUMMARY FOR AUGUST 2009 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust when significant TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized   8/1  83/63/73/+1/0/823/95    18 SSE 8/2  77/64/71/-1/T/104/12    25 SSE 8/3  84/67/76/+4/0/638/74    17 SW 8/4  83/66/75/+3/0/714/83    23 S 8/5  86/67/77/+5/T/378/44    27 SSW  TSTM 8/6  76/61/69/-3/0/564/66    18 SSE 8/7  79/58/69/-2/0/836/98    32 W 8/8  74/55/65/-6/0/791/93    21 WNW 8/9  76/59/68/-3/T/178/21    25 SSE  8/10 87/66/77/+6/0.12/584/69 27 W    TSTM  8/11 84/66/75/+4/0.54/684/81 25 NE   TSTM  8/12 67/63/65/-6/T/000/00    18 N 8/13 66/60/63/-8/0.18/042/05 23 NNE 8/14 83/58/71/+1/0/762/91    16 S 8/15 88/66/77/+7/0/810/97    18 S 8/16 90/68/79/+9/0/749/90    22 S 8/17 91/69/80/+10/0/.../..   21 WSW   8/18 our morning low temp: 72F; the normal low is now 61F   NEW DAILY RECORDS FOR AUGUST 2009 TO DATE... NONE   DAILY EXTREMES   Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR AUGUST 18 HIGH 93F IN 2002 LOW 47F IN 1824 PRECIP 5.75 INCHES IN 1955 [DIANE] PEAK GUST 46 MPH WNW 2007   RECORDS FOR AUGUST 19 HIGH 90F IN 1906, 1966, 2002 LOW 48F IN 1958 PRECIP 7.02 INCHES IN 1955 [DIANE - RECORD FOR MONTH] PEAK GUST 78 MPH ENE 1991   TODAY'S REPORT PREPARED BY: Robert Skilling