BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, AUGUST 6, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME ANOTHER INCREDIBLE MID-SUMMER DAY; COOL START, BUT WARMING NICELY THIS AFTERNOON; VERY CALM WINDS Today definitely deserved a second look at the calendar. Temperatures in several locations across the region dipped down into the 40s! Nearby Norwood airport was one of the coolest spots, with a low of 44F this morning. A sharp temperature inversion was present this morning, and with the summit of Blue Hill above it, the low temperature only managed to drop down to 56F. This afternoon, temperatures are moderating nicely, reaching the upper 70s here on the summit. The dew point temperature has been slowly creeping up through day, starting in the mid 40s early this morning and now up to the lower 50s. Today will likely finish a few degrees below the 30-year normal for the date. Including today, the recent streak of at or below normal temperatures has reached 8 days. Such a streak has not occurred since the impressive run of cool temperatures from March 14-25, 2013. With the center of a surface high pressure system over New England, winds have been very low today, with a peak wind gust so far of only 12 mph. Several periods of completely calm conditions have also occurred today. Today's Observations: 7 A.M. Weather: Scattered dense cirrus, scattered thin cirrus, patches of dense cirrus NW-NE-E, inversion present, thin smoke layer along horizon NNW-E, light distant haze, looming of mountains/hills distant NNW-N Temperature: 64F; Dew Point: 48F; Wind: Estimated W at 1 kt, Wind: Very light and variable Sea-level pressure: 30.13 ins. Hg, rising Visibility: 80 miles, light distant haze 6-hr min. temp: 56F BHO SA 1155 220 SCT 250 –SCT 80 204/64/48/E2701/013/ PTCHS DNS CI NW-NE-E INVSN PRSNT THN K LYR ALG HRZN NNW-E LGT DSNT HZ LOOMING DSNT NNW-N WND LGT AND VRB/ 8/002 52020 10064 20056 10 A.M. Weather: Scattered dense cirrus, scattered thin cirrus, few small cumulus forming distant W-N, few moderate cumulus along horizon SW, few altocumulus lenticularis distant NNW-N, patches of dense cirrus WNW-N-ENE, cirrus distant SSW and WSW-N-ESE, mostly clear sky ESE-WSW, light distant haze Temperature: 71F; Dew Point: 49F; Wind: Estimated NW at 2 kts, Wind: Very light and variable Sea-level pressure: 30.15 ins. Hg, rising Visibility: 75 miles, light distant haze BHO SA 1455 220 SCT 250 –SCT 75 209/71/49/E3102/015/ FEW SML CU FRMG DSNT W-N FEW MDT CU ALG HRZN SW FEW ACSL DSNT NNW-N PTCHS DNS CI WNW-N-ENE CI DSNT SSW AND WSW-N-ESE MSTLY CLR SKY ESE-WSW LGT DSNT HZ WND LGT AND VRB/ 8/242 50005 1 P.M. Weather: Scattered cumulus, scattered altocumulus, scattered dense cirrus, scattered thin cirrus, cumulus all quadrants except distant NNE-ESE, few moderate cumulus SE-SE-NNW, few altocumulus lenticularis distant NE, few patches of dense cirrus NW-NE, cirrus SW-N-E and distant SSE-SSW, light distant haze Temperature: 75F; Dew Point: 51F; Wind: Estimated NNW at 3 kts, Wind: Light and variable Sea-level pressure: 30.15 ins. Hg, steady Visibility: 75 miles, light distant haze 6-hr max. temp: 77F BHO SA 1755 55 SCT 120 SCT 220 SCT 250 –SCT 75 209/75/51/E3303/015/ CU ALQDS XCPT DSNT NNE-ESE FEW MDT CU SE-SW-NNW FEW ACSL DSNT NE FEW PTCHS DNS CI NW-NE CI SW-N-E AND DSNT SSE-SSW LGT DSNT HZ WND LGT AND VRB/ 8/242 54000 10077 20064 WEATHER SUMMARY FOR MONDAY, AUGUST 5, 2013 TEMPERATURE (DEGREES F) MAX.....75 NORMAL.....81 MIN.....54 NORMAL.....63 MEAN....65 NORMAL.....72 DEPARTURE FROM 30-YEAR NORMAL...................-7 TOTAL DEPARTURE FOR THE MONTH..................-12 [-2.6 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY.............0 DEPARTURE.........-7 TOTAL COOLING UNITS FOR THE MONTH............23 DEPARTURE........-13 TOTAL COOLING UNITS FOR THE SEASON..........506 DEPARTURE.......+119 TOTAL COOLING UNITS LAST SEASON TO DATE.....507 DIFFERENCE........-1 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY................26 WNW AT 9:04 A.M. AERO.....................25 WNW AT 9:04 A.M. ASOS.....................26 WNW AT 9:05 A.M. DAVIS....................27 WNW AT 9:04 A.M. RMY 27 FASTEST MILE FOR YESTERDAY..................19 WNW AT 9:04 A.M. * MAXIMUM 2-MINUTE ASOS AVERAGE...............18 NW AT 4:24 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..............19 WNW AT 9:05 A.M. AVERAGE WIND SPEED AND DIRECTION...........11.3 WNW ASOS....................10.1 DAVIS....................9.8 WNW[303 deg.] * last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE............-0.15 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.24 DEPARTURE............-0.51 ASOS..............0.23 TOTAL PRECIPITATION FOR THE YEAR..........35.53 DEPARTURE............+3.79 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals PRELIMINARY CLIMATE SUMMARY FOR AUGUST 2013 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust RMY: RMY = R.M. Young wind gust recording system added 8/9/2011 TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 8/1 81/62/72/0/0.01/.../.. 25 S AERO 26 MPH S RMY 27 8/2 81/62/72/0/0.23/.../.. 26 W AERO 26 MPH W RMY 28 8/3 77/63/70/-2/T/.../.. 22 WSW AERO 23 MPH WSW RMY 23 8/4 79/58/69/-3/T/.../.. 25 WNW AERO 21 MPH WNW RMY 26 8/5 75/54/65/-7/0.00/.../.. 26 WNW AERO 25 MPH WNW RMY 27 8/6 morning low temp: 56F; the normal low is now 63F DAILY RECORDS FOR AUGUST 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR AUGUST 6 HIGH 95F IN 1931 LOW 48F IN 1934 PRECIP 1.47 INCHES IN 1995 PEAK GUST 44e MPH SSW IN 1940 RECORDS FOR AUGUST 7 HIGH 95F IN 1924 LOW 51F IN 2004 PRECIP 3.32 INCHES IN 1926 PEAK GUST 51 MPH NE 1975 TODAY'S REPORT PREPARED BY: Sean Fankhauser