BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, JUNE 24, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME WARM AND MUGGY THIS MORNING...THUNDERSTORMS LIKELY THIS AFTERNOON Temperatures were once again well above normal on Thursday as warm, humid air continues to spread through the region. After an overnight low of 68F the air temperature reached 77F by 8:00 A.M. EDT, marking the highest temperature for the first observation since August 22, 2009. Meanwhile, the dew point has hovered around 70F making conditions quite uncomfortable on the summit. A strong cold front is expected to pass by later this afternoon bringing a significant chance of thunderstorms. Today's observations: 7 A.M. Weather: Thin overcast cirrus, patches of dense cirrus all quadrants, patches of virga break in overcast southwest, few altocumulus lenticularis distant southwest thru northwest, hazy Temperature: 77F, Dew point: 67F; Wind: SSW at 13 kts Sea-level pressure: 29.75 inches Hg, falling Visibility: 15 miles, haze 6-hour minimum temp: 68F BHO SA 1155 250 –OVC 15 073/77/67/2013/975/ PTCHS DENS CI ALQDS PTCHS VIRGA BINOVC SW FEW ACSL DSNT SW-NW HAZY/ 8/042 55015 10077 20068 10 A.M. Weather: Broken altocumulus, few altocumulus castellanus distant northeast, sun dimly visible, hazy Temperature: 83F, Dew point: 70F; Wind: SW at 13 kts, Sea-level pressure: 29.70 inches Hg, falling Visibility: 15 miles, haze BHO SA 1455 E120 BKN 15 057/83/70/2313/970/ FEW ACC DSNT NE SUN DMLY VSBL HAZY/ 8/080 56016 1 P.M. Weather: Scattered altocumulus, thin broken cirrus, cumulus forming all quadrants, moderate cumulus building west thru north, altocumulus lenticularis southwest thru north, hazy Temperature: 89F, Dew point: 69F; Wind: SW at 16G24 kts, Peak gust past hour: 26 kts WSW at 12:43 P.M. EST Wind: Direction variable S to W Sea-level pressure: 29.65 inches Hg, falling Visibility: 15 miles, haze 6-hour maximum temp: 89F BHO SA 1755 120 SCT 250 -OVC 15 039/89/69/2216G24/965/ CU FRMG ALQDS MDT CU BLDG W-N ACSL SW-N HAZY PK WND 2526/43 WND 18V28/ 8/241 58018 10089 20077 WEATHER SUMMARY FOR WEDNESDAY, JUNE 23 TEMPERATURE (DEGREES F) MAX.....84 NORMAL.....78 MIN.....65 NORMAL.....58 MEAN....75 NORMAL.....68 DEPARTURE FROM 30-YEAR AVERAGE................+7 TOTAL DEPARTURE FOR THE MONTH................+53 [+2.1 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............0 DEPARTURE........-1 TOTAL HEATING UNITS FOR THE MONTH............37 DEPARTURE.......-30 TOTAL HEATING UNITS FOR THE SEASON.........5678 DEPARTURE......-686 TOTAL HEATING UNITS LAST SEASON TO DATE....6225 DIFFERENCE.....-547 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............32 W AT 10:16 A.M. AEROVANE..............32 W AT 9:25 P.M. ASOS..................31 WSW AT 10:16 A.M. DAVIS.................32 W AT 10:31 A.M. THE FASTEST MILE FOR YESTERDAY...........24 W AT 10:17 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE............24 WSW AT 10:16 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........22 W AT 10:32 A.M. AVERAGE WIND SPEED AND DIRECTION........12.5 W ASOS.................12.2 DAVIS................11.2 SW [232 DEG] 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..........2.33 DEPARTURE........-0.69 ASOS..............2.29 TOTAL PRECIPITATION FOR THE YEAR..........35.74 DEPARTURE.......+10.98 ASOS.............35.77 PRELIMINARY CLIMATE SUMMARY FOR JUNE 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 6/1 82/57/70/+8/0.86/0/199/22 33 WNW AERO 38 MPH WNW TSTM 6/2 80/59/70/+8/0.00/752/83 22 S 6/3 80/59/70/+8/T/263/29 28 S AERO 31 MPH S TSTM 6/4 84/59/72/+9/0/499/55 23 SSW 6/5 83/63/73/+10/0.16/309/34 32 W AERO 36 MPH W TSTM 6/6 80/54/67/+4/0.07/064/07 43 S AERO 48 MPH S TSTM 6/7 72/51/62/-2/T/683/75 27 W AERO 30 MPH WNW 6/8 69/51/60/-4/T/812/89 30 WNW AERO 33 MPH WNW 6/9 70/49/60/-4/0.18/247/27 27 SSW 6/10 58/50/54/-10/0.13/0/0 22 ESE 6/11 68/53/61/-4/0/320/35 20 S 6/12 66/55/61/-4/0.22/091/10 18 SSE 6/13 64/56/60/-5/0.02/0/0 18 N 6/14 75/56/66/+1/0.01/247/27 22 NNW 6/15 77/53/65/-1/0/889/97 21 WNW 6/16 75/56/66/0/0.10/238/26 29 S AERO 31 MPH S 6/17 72/58/65/-1/0.01/128/14 29 WNW 6/18 86/58/72/+6/0/889/97 21 SW 6/19 83/63/73/+6/0/889/97 32 S 6/20 87/63/75/+8/0.50/431/47 63 SSW AERO 66 MPH SSW TSTM 6/21 86/66/76/+9/0/.../.. 21 N 6/22 79/63/71/+4/T/.../.. 21 SSE 6/23 84/65/75/+7/0.07/.../.. 32 W 6/24 our overnight low temp: 68F; the normal low is now 58F NEW DAILY RECORDS FOR JUNE 2010 6/20 - Peak wind gust of 63 MPH SSW equals record for the date of 63 MPH NE in 1967. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JUNE 24 HIGH 91F IN 1914,1976 LOW 40F IN 1932 PRECIP 2.80 INS IN 1929 PEAK GUST 46 MPH S IN 1985 RECORDS FOR JUNE 25 HIGH 93F IN 1943,1980,2005 LOW 47F IN 1903 PRECIP 1.10 INS IN 2006 PEAK GUST 51 MPH W IN 1960 TODAY'S REPORT PREPARED BY: Eli Melaas / Stephanie Radner