BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY WEDNESDAY, SEPTEMBER 23, 2009 ALL TIMES ARE IN EASTERN STANDARD TIME 2ND WARMEST HIGH TEMPERATURE OF THE MONTH CONSIDERABLE HIGH CLOUDINESS MUCH OF IT DENSE INCREASINGLY GUSTY S-SSW WINDS TO OVER 30 MPH As of early this afternoon the maximum temperature of 77F is a three-way tie for 2nd warmest during the month. The high for the month remains safely at 81F on the 5th. Considerable high altocumulus and dense cirrus is shutting out much of the bright sunshine, but not quite as much as it did yesterday. The south to south-southwest wind is becoming busy by early afternoon with gusts of over 30 MPH at times and the 2-minute sustained average has reached 24 MPH. Today's observations: 7 A.M. Weather: Broken stratocumulus, broken altocumulus, and overcast cirrus, break in overcast NW-N and distant ESE-SE, overcast partly thin W-N Temperature: 66F, Dew point: 61F, Wind: SSW at 13 kts, Sea-level pressure: 30.17 inches Hg, falling Visibility: 35 miles, light distant haze 6-hour minimum temp: 62F 24-hour precipitation: 0.00 BHO SA 1155 E40 BKN 120 BKN 250 OVC 35 218/66/61/2113/017/ BINOVC NW-N AND DSNT ESE-SE OVC PTLY THN W-N LGT DSNT HZ/ 8/531 56005 10066 20062 10 A.M. Weather: Broken altocumulus, broken dense cirrus, overcast cirrus, breaks in overcast, overcast partly thin, light distant haze Temperature: 71F, Dew point: 64F, Wind: SSW at 10 kts, Wind: Direction variable S to WSW Sea-level pressure: 30.18 inches Hg, rising Visibility: 35 miles BHO SA 1455 E140 BKN 220 BKN 250 OVC 35 220/71/64/2110/018/ SC N-NE PTCHS DENS CI BINOVC OVC PTLY THN LGT DSNT HZ WND 17V24/ 8/572 51002 1 P.M. Weather: Scattered altocumulus, altocumulus lenticularis, and altocumulus of a chaotic sky, scattered dense cirrus, thin broken cirrus, few cirrocumulus and cirrocumulus lenticularis Temperature: 76F, Dew point: 64F, Wind: SSW at 19G26 kts, Wind: Peak wind gust 27 kts S at 12:42 p.m., Wind: Direction variable S-WSW Sea-level pressure: 30.09 inches Hg, falling Visibility: 40 miles, light distant haze 6-hourly max. temp: 77F BHO SA 1755 130 SCT 150 SCT 200 SCT 220 SCT 250 –BKN 40 188/76/64/2019G26/009/ FEW SC ALQDS FEW ACSL/AC CHAOTIC SKY DENS CI ALQDS LGT DSNT HZ PK WND 1927/42/ WND 18V24/ 8/592 58032 10077 20066 WEATHER SUMMARY FOR TUESDAY, SEPTEMBER 22 TEMPERATURE (DEGREES F) MAX.....74 NORMAL.....69 MIN.....55 NORMAL.....51 MEAN....65 NORMAL.....60 DEPARTURE FROM 30-YEAR AVERAGE...........+5 TOTAL DEPARTURE FOR THE MONTH...........-26 [-1.4 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............0 DEPARTURE.......-6 TOTAL HEATING UNITS FOR THE MONTH............76 DEPARTURE.......-4 TOTAL HEATING UNITS FOR THE SEASON..........110 DEPARTURE.......-1 TOTAL HEATING UNITS LAST SEASON TO DATE......81 DIFFERENCE.....+29 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............27 SSW AT 10:43 A.M. AEROVANE..............23 SSW AT 10:43 A.M. ASOS..................24 SSW AT 11:36 A.M. DAVIS................ 27 SSW AT 10:43 A.M. FASTEST MILE FOR YESTERDAY...............19 SSW AT 10:45 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE............18 SSW AT 11:35 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........21 SSW AT 10:41 A.M. AVERAGE WIND SPEED AND DIRECTION.......11.6 SSW ASOS................11.5 DAVIS...............11.9 SSW [210 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M... 0.00 DEPARTURE....-0.14 ASOS..............0.00 TOTAL PRECIPITATION FOR MONTH..............2.29 DEPARTURE....-0.72 ASOS..............2.33 TOTAL PRECIPITATION FOR THE YEAR..........37.06 DEPARTURE....+0.58 ASOS.............38.25 PRELIMINARY CLIMATE SUMMARY FOR SEPTEMBER 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 9/1 71/51/61/-6/0/773/98 17 NW 9/2 76/54/65/-1/0/786/100 22 S 9/3 77/56/67/+1/0/587/75 19 SW 9/4 77/60/69/+3/0/764/98 18 NE 9/5 81/59/70/+5/0/591/76 25 NNW 9/6 64/53/59/-6/0/743/96 31 NNE 9/7 70/52/61/-4/0/709/92 20 WSW 9/8 75/56/66/+1/0/369/48 18 WSW 9/9 68/55/62/-2/0/352/46 36 NNE AERO 33 MPH NNE 9/10 65/53/59/-5/0/603/79 31 ENE 9/11 61/54/58/-6/0.49/000/00 30 NE 9/12 63/60/62/-1/1.74/000/00 30 NNE 9/13 76/58/67/+4/0.06/393/52 28 NW 9/14 74/55/65/+2/0/699/93 22 WSW 9/15 75/56/66/+4/0/682/91 22 WNW 9/16 61/53/57/-5/T/060/08 31 NNE AERO 29 MPH NNE 9/17 60/49/55/-7/0/022/03 27 N 9/18 71/47/59/-2/T/571/77 35 WSW AERO 30 MPH WSW 9/19 65/45/55/-6/0/716/97 30 NW AERO 28 MPH WNW 9/20 71/45/58/-3/0/721/98 22 SW 9/21 76/50/63/+3/0/703/96 20 S 9/22 74/55/65/+5/0/124/17 27 SSW 9/23 our morning low temp: 61F; the normal low is now 51F NEW DAILY RECORDS FOR SEPTEMBER 2009 TO DATE... None. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR SEPTEMBER 23 HIGH 93F IN 1895,1914 LOW 33F IN 1904 PRECIP 2.67 INCHES IN 1994 PEAK GUST 62 MPH SSW IN 1989 RECORDS FOR SEPTEMBER 24 HIGH 87F IN 1959 LOW 33F IN 1885,1950,1963 PRECIP 1.19 INCHES IN 1955 PEAK GUST 54e MPH SW IN 1940 TODAY'S REPORT PREPARED BY: Robert Skilling