BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, SEPTEMBER 7, 2012 ALL TIMES ARE IN EASTERN STANDARD TIME WARM, HAZY, SUNNY, AND CALM Temperatures are running several degrees above normal today with a morning low of 66F and an afternoon high of at least 84F. The day began with the summit shrouded in fog and visibility reduced to 1/8 of a mile. The fog/stratus layer slowly began to lift and dissipate after the 7 AM EST observation, and the sky became mostly sunny. Mostly sunny conditions have prevailed today, with scattered moderate cumulus developing early this afternoon. Moisture has remained quite abundant in the air, with dew point temperatures nearing 70F. Consequently, visibility has been less than impressive, but none the less reaching 40 miles to the WNW this afternoon. Winds have been from the S-SW since Thursday afternoon, and the winds continue to be quite light, only reaching a peak of 20 mph late Thursday night. Today's observations: 7 A.M. Weather: Sky partially obscured by fog, stratus drifting over summit, sun disc visible, fog dissipating, heavy dew all surfaces Temperature: 68F; Dew Point: 68F; Wind: SSW at 5 kts. Sea-level pressure: 29.94 ins. Hg, rising Visibility: 2 miles, fog, fog dissipating and visibility increasing 6-hour min. temp: 66F BHO SA 1155 –X E100 BKN 2F 138/68/68/2105/994/ F7 STRA DRFTNG OVR SMT SUN DISC VSBL FG DSPTNG VSBY INCRSNG HVY DEW ALL SFCS/ 8/630 51014 10068 20066 10 A.M. Weather: Scattered cumulus, scattered altocumulus, scattered thin cirrus, cumulus/cumulus fractus distant SE-SW, lone cumulus over city to the N and to the ENE, few altocumulus castellanus WSW and NNW-N, altocumulus lenticularis ESE and S-W-N, hazy Temperature: 77F; Dew Point: 69F; Wind: estimated S at 3 kts, Wind: Light and variable Sea-level pressure: 29.95 ins. Hg, rising Visibility: 25 miles, hazy BHO SA 1455 10 SCT 100 SCT 250 –SCT 25 142/77/69/E1803/995/ CU/CUFRA DSNT SE-SW LONE CU OVR CTY N AND ENE FEW ACC WSW AND NNW-N ACSL ESE AND S-W-N HAZY WND LGT AND VRB/ 8/181 50004 1 P.M. Weather: Scattered cumulus, scattered altocumulus (2 levels), few moderate cumulus all quadrants, towering cumulus WNW and NNe, altocumulus NNW-ENE, hazy Temperature: 83F; Dew Point: 69F; Wind: SSW at 7 kts, Wind: Direction variable S-WSW Sea-level pressure: 29.94 ins. Hg, falling Visibility: 30 miles, WNW 40 miles, hazy 6-hour max. temp: 84F BHO SA 1755 30 SCT 80 SCT 100 SCT 30 138/83/69/2107/994/ FEW MDT CU ALQDS TCU WNW AND NNE AC NNW-ENE VSBY WNW 40 HAZY WND 18V24/ 8/340 56004 10084 20068 WEATHER SUMMARY FOR THURSDAY, SEPTEMBER 6 TEMPERATURE (DEGREES F) MAX.....77 NORMAL.....75 MIN.....62 NORMAL.....58 MEAN....70 NORMAL.....67 DEPARTURE FROM 30-YEAR NORMAL.....................+3 TOTAL DEPARTURE FOR THE MONTH....................+10 [+1.5 deg/day] PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............20 SSW AT 10:59 P.M. * AERO..................20 SSW AT 10:59 P.M. ASOS..................18 SSW AT 11:21 P.M. DAVIS.................19 S AT 11:21 P.M. RMY 19 THE FASTEST MILE FOR YESTERDAY...........14 SSW AT 11:01 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE............15 SSW AT 11:14 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........15 S AT 11:14 P.M. AVERAGE WIND SPEED AND DIRECTION........6.5 SW ASOS.................6.1 DAVIS................6.0 S [188 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..........0.71 DEPARTURE............0.00 ASOS..............0.69 TOTAL PRECIPITATION FOR THE YEAR..........26.06 DEPARTURE...........-9.67 ASOS.............25.95 PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 2012 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 9/1 75/60/68/0/0.00/.../.. 27 ENE AERO 25 MPH ENE RMY 23 9/2 80/60/70/+2/0.00/.../.. 21 ENE AERO 20 MPH ENE RMY 20 9/3 76/57/67/0/0.00/.../.. 20 SE AERO 20 MPH S RMY 21 9/4 72/62/67/0/0.40/000/00 25 S AERO 23 MPH S RMY N/A 9/5 79/64/72/+5/0.31/.../.. 33 SSW AERO 35 MPH SSW RMY 33 9/6 77/62/70/+3/0.00/.../.. 20 SSW AERO 20 MPH SSW RMY 19 9/7 morning low temp: 65F; the normal low is now 58F DAILY RECORDS FOR SEPTEMBER 2012 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR SEPTEMBER 7 HIGH 92F IN 2007 LOW 40F IN 1888 PRECIP 2.95 INCHES IN 1891 PEAK GUST 58e MPH W IN 1941 RECORDS FOR SEPTEMBER 8 HIGH 93F IN 2007 LOW 42F IN 1978 PRECIP 1.51 INCHES IN 2011 PEAK GUST 40e MPH NW IN 1941, WSW IN 1944 TODAY'S REPORT PREPARED BY: Sean Fankhauser