BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY WEDNESDAY, SEPTEMBER 11, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME TRIPLE "H" WEATHER....HOT, HAZY, AND HUMID MAXIMUM TEMP. JUST SHY OF RECORD AT 2 P.M. THEN RISES TO 93F AFTER 2 P.M. EQUALING RECORD THE DEW POINT HAD DROPPED FROM 75F EARLIER to 72F The maximum temperature was just shy of equaling today's record high maximum of 93F set in 1983 as our official thermometer had reached 92.4F just before 2 P.M. Then a bit later we equaled the 93-degree record. Dew points continue to be especially high for September ranging between 70F and 75F today. Today is extremely humid. The dew point was as high as 70 degrees at 7 am this morning and 75F later this morning. Along with high humidity our overnight low was very warm at 68 degrees. That is 12 degrees above the average low of 58. The heat and humidity will continue throughout the day. A record high maximum and record high minimum may be both broken during the next 24 hours. The high maximum and high minimum for today were both set in 1983 at 93 and 71 degrees. Tonight's low may set a new high minimum for September 12. The record currently stands at 69F in 1925. By 10 o'clock we had an observed temperature of 84.6 and a wet bulb of 77.0. This made for a dew point of 74 degrees that also agrees with ASOS. This makes it a remarkable day of for high heat and humidity for the month of September. A foggy morning turned into a hazy day. A rather thick haze at mid-morning had thinned out by early after with visibility increasing from 9 miles at mid- morning to 15 to 20 miles early this afternoon. As of 2:45 P.M. my Hingham National Weather Service cooperative station has set a new daily record of 96F breaking the old 1983 record of 94 degrees set September 11, 1983. Today’s Observations: 7 A.M. Weather: Partially obscured with 1/10, fog, scattered altocumlos castellanus dissipating past hour, heavy dew and condensation Temperature: 71F; Dew Point: 70F; Wind: SSW at 8 kts. Sea-level pressure: 30.09 ins Hg, rising slightly Visibility: 2 miles in fog 24-hr precip: 0.03 6-hr min. temp: 68F BHO SA 1155 –X 80 SCT 2F 189/71/70/2108/009/ F1 FEW ACC AND DSSPTNG PST HR HVY DEW/CONDENSATION ALL SFCS/ 8/080 51005 MANUAL 70003 ASOS 70004 10071 20068 10 A.M. Weather: Clear, few cirrus SE-SW, Haze layer above horizon SW-N Temperature: 84F; Dew Point: 74F; Wind: SW at 9 kts, Sea-level pressure: 30.09 ins. Hg, steady Visibility: 9 miles, hazy BHO SA 1455 CLR 9 189/84/74/2209/009/ FEW CI SE-SE HZ LYR ABV HRZN SW-N HAZY ALQDS/ 8/001 50000 1 P.M. Weather: Clear, small patch cirrus E-ESE Temperature: 92F; Dew Point: 72F; Wind: SW at 9 kts, Wind: Direction variable S-W Sea-level pressure: 30.05 ins. Hg, falling then more rapidly Visibility: 15 miles, except 20 miles WNW, hazy 6-hr max. temp: 92F BHO SA 1755 CLR 15 176/92/72/2209/005/ SML PTCH CI E-SE VSBY WNW 20 HAZY ALQDS WND 18V27/ 8/001 58013 10092 20071 WEATHER SUMMARY FOR TUESDAY, SEPTEMBER 10, 2013 TEMPERATURE (DEGREES F) MAX.....73 NORMAL.....74 MIN.....56 NORMAL.....57 MEAN....65 NORMAL.....65 DEPARTURE FROM 30-YEAR NORMA..............0 TOTAL DEPARTURE FOR THE MONTH...........-18 [-2.0 DEGREES/DAY] COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY..........0 DEPARTURE.....-3 TOTAL COOLING UNITS FOR THE MONTH.........23 DEPARTURE.....-9 TOTAL COOLING UNITS FOR THE SEASON.......663 DEPARTURE....+94 TOTAL COOLING UNITS LAST SEASON TO DATE..754 DIFFERENCE...-91 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...........30 S AT 11:19 A.M. AERO...................................32 S AT 11:23 A.M. * ASOS...................................33 S AT 11:20 A.M. DAVIS..................................32 S AT 11:19 A.M. RMY 33 FASTEST MILE FOR YESTERDAY.............23 S AT 11:35 A.M.* MAXIMUM 2-MINUTE ASOS AVERAGE..........23 SSW AT 11:32 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.........22 S AT 11:00 A.M. AVERAGE WIND SPEED AND DIRECTION.....15.3 SSW ASOS.......14.3 DAVIS.......14.4 SSW [200 degrees] * last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.03 DEPARTURE.....-0.10 ASOS......0.04 TOTAL PRECIPITATION FOR THE MONTH..........2.86 DEPARTURE.....+1.63 ASOS......2.95 TOTAL PRECIPITATION FOR THE YEAR..........40.87 DEPARTURE.....+4.62 ASOS......N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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 9/1 76/67/72/+4/2.32/008/01 33 S AERO 39 MPH S RMY 38 TSTM 9/2 79/67/73/+5/0.43/056/07 30 SSE AERO 33 MPH SSE RMY N/A TSTM 9/3 79/61/70/+3/0.00/219/28 28 S AERO 29 MPH S RMY 30 TSTM 9/4 78/57/68/+1/0.00/733/94 24 W AERO 25 MPH W RMY 25 9/5 66/51/59/-8/0.08/179/23 20 NNE AERO 20 MPH NNE RMY 21 9/6 68/46/57/-10/0.00/751/97 18 WSW AERO 17 MPH WSW RMY N/A 9/7 78/51/65/-1/0.00/594/77 20 WSW AERO 21 MPH WSW RMY 21 9/8 74/50/62/-4/0.00/646/84 31 NW AERO 33 MPH NW RMY 32 9/9 69/47/58/-8/T/../.../.. 23 SW AERO 23 MPH SSW RMY N/A 9/10 73/56/65/0/0.03/.../.. 30 S Aero 32 MPH S RMY 33 9/11 morning low temp: 68F; the normal low is now 56F DAILY RECORDS FOR SEPTEMBER 2013 9/1 – NEW DAILY RECORD MAXIMUM PRECIPITATION OF 2.32 INCHES; surpasses previous record of 1.60 inches set in 1927 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR SEPTEMBER 11 HIGH 93F IN 1983 LOW 37F IN 1917 PRECIP 5.23 INCHES IN 1954 (HURRICANE EDNA) PEAK GUST 101 MPH NW IN 1954 (HURRICANE EDNA) RECORDS FOR SEPTEMBER 12 HIGH 92F IN 1961 LOW 42F IN 1958,1967,1985 PRECIP 2.79 INCHES IN 1960 (HURRICANE DONNA) PEAK GUST 140 MPH SSE IN 1960 (HURRICANE DONNA) TODAY’S REPORT PREPARED BY: Robert Skilling and Kevin Pecora