BLUE HILL OBSERVATORY MILTON, MA MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, OCTOBER 30, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME TEMPERATURES RETURN TO NEAR AVERAGE THIS WEEKEND... OCTOBER LIKELY TO FINISH WARMER THAN AVERAGE... The morning low was a chilly 35 degrees with a steady breeze picking up after sunrise. This is four degrees cooler than normal for the date. There still has not been a freeze on the summit this season more than a week after the average date. A slightly cool finish to the month this weekend will not be below average enough to prevent October from finishing warmer than normal with a cumuluative temperature departure of +31 degrees through the 29th. Today's observations: 7 A.M. Weather: Scattered altocumulus, scattered dense cirrus, thin overcast cirrus, few stratocumulus distant offshore ESE, few altocumulus lenticularis all quadrants Temperature: 36F, Dew point: 27F; Wind: WSW at 12 kts Sea-level pressure: 30.02 inches Hg, rising Visibility: 75 miles 6-hour minimum temp: 35F 24-hour precipitation: Trace BHO SA 1155 120 SCT 150 SCT 220 SCT 250 –OVC 75 165/36/27/ 2512/002/ FEW SC DSNT OFFSHR ESE FEW ACSL ALQDS/ 8/531 51010 10039 20035 10 A.M. Weather: Scattered dense cirrus, thin overcast cirrus, few cumulus distant WNW-NNE and SE-S Temperature: 48F, Dew point: 30F; Wind: SW at 17G24 kts, Wind: Peak gust 29 kts SW at 9:16 AM EST Wind: Direction variable S-WSW Sea-level pressure: 29.96 inches Hg, falling Visibility: 70 miles BHO SA 1455 180 SCT 250 –OVC 70 147/48/30/2217G24/996/ FEW CU DSNT WNW-NNE AND SE-S PK WND 2229/16 WND 19V25/ 8/101 58018 WEATHER SUMMARY FOR FRIDAY, OCTOBER 29 TEMPERATURE (DEGREES F) MAX.....56 NORMAL.....56 MIN.....39 NORMAL.....39 MEAN....48 NORMAL.....47 DEPARTURE FROM 30-YEAR NORMAL...............+1 TOTAL DEPARTURE FOR THE MONTH..............+31 [+0.9 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............17 DEPARTURE........-1 TOTAL HEATING UNITS FOR THE MONTH...........357 DEPARTURE.......-29 TOTAL HEATING UNITS FOR THE SEASON..........436 DEPARTURE......-119 TOTAL HEATING UNITS LAST SEASON TO DATE.....598 DIFFERENCE.....-162 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............30 WNW AT 10:48 P.M. * AEROVANE..............32 WNW AT 10:48 P.M. * ASOS..................31 NNW AT 10:48 P.M. DAVIS.................33 WNW AT 10:48 P.M. THE FASTEST MILE FOR YESTERDAY...........23 WNW AT 7:59 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE............23 WNW AT 7:03 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........25 W AT 7:03 P.M. AVERAGE WIND SPEED AND DIRECTION.......12.8 WNW ASOS................11.9 DAVIS...............13.2 W [281 DEG] * last of several occurrences... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...Trace DEPARTURE........-0.15 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........5.70 DEPARTURE........+1.58 ASOS..............5.71 TOTAL PRECIPITATION FOR THE YEAR..........53.72 DEPARTURE.......+12.00 ASOS.............53.55** ** ASOS missing rainfall due to system failure on 6/24-25 PRELIMINARY CLIMATE SUMMARY FOR OCTOBER 2010 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 10/1 80/55/68/+11/0.56/035/05 55 SSE AERO 63 MPH SSE 10/2 65/46/56/0/0.00/688/98 28 WNW AERO 31 MPH WNW 10/3 55/43/49/-7/T/133/19 35 NNE AERO 39 MPH NNE 10/4 54/48/51/-5/0.78/000/00 39 NNE AERO 43 MPH NNE 10/5 57/51/54/-1/0.40/000/00 37 NE AERO 39 MPH NNE 10/6 57/49/53/-2/1.63/000/00 47 NE AERO 51 MPH NE 10/7 62/47/55/0/0.00/275/40 37 W AERO 40 MPH W 10/8 70/47/59/+5/0.00/610/89 35 WSW AERO 37 MPH WSW 10/9 62/43/53/-1/0.00/675/99 33 WNW AERO 37 MPH WNW 10/10 64/38/51/-3/0.00/679/100 25 SW AERO 29 MPH SSW 10/11 68/47/58/+5/0.00/542/80 28 W 10/12 61/43/52/-1/0.01/297/44 24 ENE 10/13 61/38/50/-2/0.00/663/99 18 NW 10/14 59/45/52/0/0.41/294/44 29 ENE 10/15 51/39/45/-7/1.71/033/05 48 WSW AERO 50 MPH WSW TSTM 10/16 55/39/47/-4/0.00/544/82 47 WNW AERO 54 MPH WNW 10/17 63/38/51/0/0.00/581/88 43 W AERO 47 MPH W 10/18 57/41/49/-2/0.00/519/79 32 W AERO 35 MPH W 10/19 57/38/48/-3/0.00/497/76 21 W 10/20 61/44/53/+3/T/221/34 21 S 10/21 56/39/48/-2/0.07/084/13 55 W AERO 62 MPH W 10/22 47/34/41/-9/T/T/497/77 51 W AERO 56 MPH W trace snow 10/23 56/35/46/-3/0.00/470/73 32 W AERO 37 MPH W 10/24 51/39/45/-4/0.01/013/02 17 SSE 10/25 65/47/56/+7/T/013/02 36 S AERO 38 MPH S 10/26 77/62/70/+22/0.00/452/71 32 S AERO 36 MPH S 10/27 68/63/66/+18/0.11/000/00 35 S AERO 37 MPH S 10/28 75/50/63/+15/0.00/461/73 39 WSW AERO 42 MPH WSW 10/29 56/39/48/+1/T/.../.. 30 WNW 10/30 morning low temp: 35F; the normal low is 39F NEW DAILY RECORDS FOR OCTOBER 2010 10/22: Daily snowfall: Trace; equals record set in 1969. 10/26: NEW RECORD HIGH MINIMUM TEMP. OF 62F; the previous record was 57F in 1991 10/26: NEW LATE SEASON RECORD HIGH MINIMUM TEMP. 62F; the previous record was 62F on 10/22/1979 10/27: NEW RECORD HIGH MINIMUM TEMP. OF 63F; the previous record was 59F in xxxx. 10/27: NEW LATE SEASON RECORD HIGH MINIMUM TEMP: 63F; the previous record was 62F set on 10/26/2010. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR OCTOBER 30 HIGH 75 IN 1946,1989 LOW 21 IN 1928 PRECIP 1.85 INCHES IN 1917 SNOWFALL 0.6 INCHES IN 2000 PEAK GUST 66 NW IN 1963 RECORDS FOR OCTOBER 31 HIGH 79 IN 1946 LOW 22 IN 1904 PRECIP 3.74 INCHES IN 1991 SNOWFALL TRACE IN 1906 PEAK GUST 70e S IN 1945 TODAY'S REPORT PREPARED BY: Mike Iacono