BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, JULY 17, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME TEMPERATURE RISES ABOUT 80 DEGREES FOR THE FIRST TIME OF THE SUMMER The temperature reached 80 degrees at 11 AM EDT today for the first time this summer. This has set a new record for no 80 degree days until this date in the summer. We have also reached a new record for the latest instance of an 80 degree day in the month of July. The longest stretch for the month of July without reaching 80 prior to this year occurred in 1918 when it ended on July 16 with 85 degrees. The high temperature so far today as of 2:00 PM EDT was 86 degrees. Today's high temperatures brings to an end this extended stretch of below normal daily temperatures which began on June 28th. Today's observations: 7 A.M. Weather: Thin overcast cirrus, few altocumulus SW to NW, patches dense cirrus N to SE, thin smoke layer SE-SW Temperature: 69F, Dew point: 64F, Wind: WSW at 8 kts Sea-level pressure: 29.83 inches Hg, rising Visibility: 20 miles, hazy 6-hour minimum temp: 65F 24-hour precipitation: Trace BHO SA 1155 250 –BKN 20 103/69/64/2408/983/ FEW AC SW-NW PTCHS DENS CI N-SE THN K LYR SE-SW HAZY/ 8/032 53019 10069 20065 10 A.M. Weather: Thin broken cirrus Temperature: 80F, Dew point: 61F, Wind: W at 5 kts Sea-level pressure: 29.84 inches Hg, rising Visibility: 25 miles, hazy BHO SA 1455 250 –BKN 25 105/80/61/2705/984/ HAZY WND LGT AND VRB/ 8/001 51002 1 P.M. Weather: Scattered stratocumulus with moderate cumulus forming north, broken cirrostratus, thin broken cirrus, partial halo Temperature: 85F, Dew point: 59F, Wind: SW at 9 kts Wind: Direction variable S to W Sea-level pressure: 29.83 inches hg, falling Visibility: 40 miles, light haze 6-hourly max. temp. 86F BHO SA 1755 55 SCT 220 BKN 250 –BKN 40 103/85/59/2309/983/ MDT CU FRMG N PARTIAL HALO LGT HZ WND 17V27/ 8/207 55002 10086 20069 WEATHER SUMMARY FOR THURSDAY, JULY 16 TEMPERATURE (DEGREES F) MAX.....77 NORMAL.....82 MIN.....62 NORMAL.....62 MEAN....70 NORMAL.....72 DEPARTURE FROM 30-YEAR NORMAL...........-2 TOTAL DEPARTURE FOR THE MONTH..........-91 [-5.9 DEGREES/DAY] HEATING DEGREE DATA WILL RESUME IN SEPTEMBER PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............30 S AT 6:06 P.M. AEROVANE..............28 S AT 3:06 P.M. ASOS..................30 S AT 6:06 P.M. DAVIS.................30 SSW AT 1:13 P.M. FASTEST MILE FOR YESTERDAY...............21 S AT 1:23 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE............22 SSW AT 10:24 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........23 S AT 10:24 A.M. AVERAGE WIND SPEED AND DIRECTION.......13.4 S ASOS................13.3 DAVIS...............12.4 S [187 DEG] 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..........3.09 DEPARTURE....+1.15 ASOS..............3.15 TOTAL PRECIPITATION FOR THE YEAR..........26.73 DEPARTURE....-0.88 ASOS.............27.80 PRELIMINARY CLIMATE SUMMARY FOR JULY 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 7/1 62/57/60/-10/0.51/000/00 25 NNE TSTM 7/2 66/56/61/-9/1.00/000/00 29 SSW TSTM 7/3 75/58/67/-3/T/283/31 23 WSW 7/4 77/59/68/-2/0/838/92 43 W 7/5 78/54/66/-5/0/856/94 33 W 7/6 79/60/70/-1/0/883/97 20 SSE 7/7 66/58/62/-9/0.73/027/03 28 SE TSTM 7/8 67/56/62/-9/0.23/091/10 27 NNE TSTM 7/9 66/55/61/-10/0/689/76 23 NE 7/10 76/54/65/-6/0/896/99 21 SW 7/11 77/56/67/-5/0.29/686/76 36 S 7/12 78/60/69/-3/0.33/650/72 30 SSW TSTM 7/13 76/55/66/-6/0/802/89 32 SW 7/14 75/56/66/-6/0/567/63 25 WNW 7/15 79/55/67/-5/0/826/92 30 WSW 7/16 77/62/70/-2/T/161/18 30 S 7/17 our morning low temp: 65F; the normal low is now 62F NEW DAILY RECORDS FOR JULY 2009 TO DATE... NONE DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JULY 17 HIGH 96F IN 1999 LOW 47F IN 1892 PRECIP 1.39 INS IN 1989 WIND 46 MPH WNW IN 1971 RECORDS FOR JULY 18 HIGH 96F IN 1991, 1999 LOW 54F IN 1892, 1956, 1971 PRECIP 1.65 INS IN 2000 WIND 43e MPH SW IN 1949 TODAY'S REPORT PREPARED BY: Stephanie Radner