BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, JULY 26, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME 2-DAY RAINFALL TOTAL REACHES 1.05 INCHES; CONTINUED FOGGY, DAMP, AND COOL WITH NNE-NW WIND Intermittent light rain began yesterday morning and became steady by afternoon with some periods of moderate rain. The 2-day rainfall total through 2 P.M. EDT this afternoon has reached 1.05 inches. The rain was needed as it had been a relatively dry July prior to the rain. The rainfall deficit for the month has been pushed back to only about one third of an inch. With a persistent NNE wind for much of yesterday and a gradually backing wind (counterclockwise) that is now out of the NW, temperatures have been quite cool, straying only a few degrees to either side of 60F. Overcast conditions have also helped keep temperatures on the cool side. The summit had been shrouded in dense fog for much of the day, but the low stratus finally began lifting shortly after 1 P.M. EDT today. Visibility has improved to 30-35 miles this afternoon. BHO Greatest Number of 90-Degree Days per Month, (1885-2013) 1) 14 in July 1952 2) 13 in August 2002 3) 10 in August 1944 10 in July 1949 10 in July 1963 10 in July 2010 10 in July 2013 (through 7/24) 8) 9 in July 1911 9 in August 1928 10) 8 in August 1949 8 in July 1963 8 in July 1988 Today's Observations: 7 A.M. Weather: Sky obscured by dense fog and light rain, stratus drifting over summit, light rain continued Temperature: 60F; Dew Point: 60F; Wind: N at 10 kts, Wind: Direction variable NNW-NNE Sea-level pressure: 29.99 ins. Hg, falling then steady Visibility: 1/2 mile, variable 1/4 to 1 1/2 miles, NW-E 1/4 mile, ESE 1/2 mile, SSE 1 1/2 miles, SSW 1 mile, SW-NW 1/2 mile, dense fog and light rain 24-hr precip: 0.89 inch 6-hr precip: 0.46 inch (ASOS) 6-hr min. temp: 59F BHO SA 1155 W3 X 1/2VR-F 156/60/60/3610/999/ STRA DRFTNG OVR SMT VSBY 1/4V11/2 NW-E 1/4 ESE 1/2 SSE 11/2 SSW 1 SW-NW 1/2 WND 33V03 R-CTD/ 8//// 56007 ASOS 70087 MANUAL 70089 ASOS 60046 10060 20059 10 A.M. Weather: Sky obscured by dense fog and light rain, stratus drifting over summit, light rain and occasional light drizzle continued Temperature: 61F; Dew Point: 61F; Wind: NNW at 11 kts, Wind: Direction variable WNW-N Sea-level pressure: 29.98 ins. Hg, falling Visibility: 1/2 mile, variable 1/4 to 1 1/2 miles, ESE 1/2 mile, SSE 1 1/2 miles, SSW-W-NE 1/4 mile, dense fog and light rain 3-hr precip: 0.09 inch BHO SA 1455 W3 X 1/2VR-F 151/61/61/3311/998/ STRA DRFTNG OVR SMT VSBY 1/4V11/2 ESE 1/2 SSE 11/2 SSW-W-NE 1/4 WND 29V01 WND GRDLY BACKING R- OCNL L- CTD/ 8//// 56005 ASOS 60008 MANUAL 60009 1 P.M. Weather: Scattered stratus fractus, broken stratocumulus (2 levels), overcast altocumulus, few stratus fractus drifting below summit, hazy, very light and intermittent drizzle ended about 12:10 P.M. EST Temperature: 65F; Dew Point: 64F; Wind: NW at 10 kts. Wind: Direction variable WNW-N Sea-level pressure: 29.95 ins. Hg, falling Visibility: 30 miles, NNW-ENE 35 miles, ESE-SSE lower, WNW 30 miles, hazy 6-hr precip: 0.14 inch 6-hr max. temp: 65F BHO SA 1755 5 SCT E10 BKN 50 BKN 80 OVC 30 143/65/64/3210/995/ FEW STFRA DRFTNG BLO SMT HAZY VSBY NNW-ENE 35 ESE-SSE LWR WNW 30 WND 29V35 WND GRDLY BACKING L- E ABT 10 PCPN VRY LGT AND INTMT/ 8/87/ 58008 ASOS 60014 MANUAL 60014 10065 20060 WEATHER SUMMARY FOR THURSDAY, JULY 25, 2013 TEMPERATURE (DEGREES F) MAX.....64 NORMAL.....81 MIN.....57 NORMAL.....63 MEAN....61 NORMAL.....72 DEPARTURE FROM 30-YEAR NORMAL.....................-11 TOTAL DEPARTURE FOR THE MONTH....................+122 [+4.7 DEGREES/DAY] PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY................24 NNE AT 12:08 P.M. AERO.....................24 NNE AT 12:08 P.M. ASOS.....................25 NNE AT 12:09 P.M. DAVIS....................24 NNE AT 12:08 P.M. RMY 25 FASTEST MILE FOR YESTERDAY..................17 NNE AT 12:08 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...............16 NE AT 12:10 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..............16 NNE AT 11:39 A.M. AVERAGE WIND SPEED AND DIRECTION..........10.7 NNE ASOS....................9.9 DAVIS...................9.5 NNE [018 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.89 DEPARTURE............+0.75 ASOS..............0.87 TOTAL PRECIPITATION FOR THE MONTH..........2.74 DEPARTURE............-0.39 ASOS..............2.72 TOTAL PRECIPITATION FOR THE YEAR..........34.94 DEPARTURE............+4.84 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals PRELIMINARY CLIMATE SUMMARY FOR JULY 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 7/1 82/69/76/+6/0.05/247/27 29 S AERO 31 MPH SSW RMY 32 7/2 82/61/72/+2/T/100/11 23 SSW AERO 23 MPH SSW RMY 25 7/3 87/62/75/+4/T/556/61 28 SW AERO 30 MPH SW RMY 30 7/4 90/71/81/+10/0.00/811/89 25 WSW AERO 26 MPH SW RMY 28 7/5 92/73/83/+12/0.00/874/96 24 W AERO 25 MPH WSW RMY 25 7/6 90/73/82/+11/0.00/836/92 25 WNW AERO 25 MPH WNW RMY 26 7/7 91/72/82/+11/0.21/508/56 38 SSW AERO 43 MPH SSW RMY 44 TSTM 7/8 82/64/73/+1/0.04/617/68 18 NE AERO 20 MPH NE RMY 20 TSTM 7/9 72/63/68/-4/0.01/054/06 14 ENE AERO 14 MPH ENE RMY 14 7/10 84/65/75/+3/T/335/37 32 S AERO 36 MPH S RMY 35 7/11 79/69/74/+2/0.62/009/01 23 W AERO 23 MPH W RMY N/A TSTM 7/12 70/62/66/-6/0.00/162/18 29 NE AERO 29 MPH NE RMY 30 7/13 75/62/69/-3/0.08/009/01 21 ENE AERO 20 MPH ENE RMY N/A 7/14 89/71/80/+8/0.00/477/53 16 W AERO 16 MPH W RMY 16 7/15 91/72/82/+10/0.00/665/74 17 NW AERO 16 MPH NW RMY 18 7/16 91/71/81/+9/0.00/843/94 18 NNW AERO 16 MPH NNW RMY 16 7/17 93/74/84/+12/0.00/841/94 22 SW AERO 23 MPH SW RMY 25 7/18 90/75/83/+11/0.00/724/81 20 S AERO 21 MPH S RMY 22 7/19 95/76/86/+14/0.00/723/81 36 WSW AERO 38 MPH WSW RMY 38 7/20 93/72/82/+10/0.00/570/64 29 W AERO 30 MPH W RMY 31 TSTM 7/21 82/68/75/+3/0.00/.../.. 16 NE AERO 16 MPH NE RMY 17 7/22 80/67/74/+2/T/.../.. 17 NE AERO 17 MPH NE RMY 19 TSTM 7/23 82/68/75/+3/0.82/.../.. 35 WSW AERO 36 MPH WSW RMY 39 TSTM 7/24 84/64/74/+2/0.00/.../.. 23 N AERO 23 MPH N RMY 23 7/25 64/57/61/-11/..../000/00 24 NNE AERO 24 MPH NNE RMY 25 7/26 morning low temp: 59F; the normal low is now 63F DAILY RECORDS FOR JULY 2013 7/14 - TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F; ties previous record of 71F set in 1997 7/15 - NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 72F; surpasses previous record of 70F set in 1901, 1934, 1995 7/16 - TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 71F; ties previous record of 71F set in 1901, 1958, 1968 7/17 - TIED DAILY RECORD HIGH MINIMUM TEMPERATURE OF 74F; ties previous record of 74F set in 1900 7/18 - NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 75F; surpasses previous record of 73F set in 1900, 1999 7/19 - NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 76F; surpasses previous record of 72F set in 1949, 1991, 2005 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JULY 26 HIGH 97F IN 1963 LOW 47F IN 1920 PRE 2.05 INS IN 1899 WIND 74e MPH NNW IN 1940 RECORDS FOR JULY 27 HIGH 95F IN 1949, 1963 LOW 50F IN 1920, 2001 PRE 4.01 INS IN 1979 WIND 47 MPH ENE IN 1984 TODAY'S REPORT PREPARED BY: Sean Fankhauser