BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, APRIL 19, 2008 ALL TIMES ARE IN EASTERN STANDARD TIME UNLESS NOTED WARM AND DRY CONDITIONS CONTINUE WITH FULL SUNSHINE... VERY STRONG TEMPERATURE INVERSION FORMED THIS MORNING... It will be another dry day with close to full sunshine and warm temperatures. The low temperature on the summit of 60 this morning was 24 degrees warmer than the low of 36 recorded at the nearby, low-lying Norwood Airport about 3.5 miles to the SW and roughly 500 feet below the summit. The low of 60 is slightly higher than the present record high minimum for this date of 58 set in 1976, though it may get cooler than this by midnight. The dew point has climbed to the upper 30s today, though the relative humidity remains low also in the 30s. The fire danger is begining to rise due to the dry conditions this week, which are expected to continue into next week. Friday sunshine was about 88 percent after three straight days of 100 percent. Today's observations: 8 A.M. EDT Weather: Clear, few cirrus and altocumulus Temperature: 63F, Dew point: 31F Wind: ENE at 5 kts Sea-level pressure: 30.08 inches Hg, rising Visibility: 40 miles 6-hour min temp: 60F 24-hour precipitation: none BHO SA 1155 CLR 40 185/63/31/0705/008/ FEW CI NNE FEW AC DSNT SSW K LYR BLO INVSN SW-NNE HAZY WND LGT/ 8/031 51017 10063 20060 11 A.M. EDT Weather: Clear Temperature: 67F, Dew point: 37F, Wind: NE at 6 kts Wind: Light and variable Sea-level pressure: 30.11 inches Hg, rising Visibility: 35 miles, hazy BHO SA 1455 CLR 35 195/67/37/0406/011/ HAZY WND LGT AND VRB/ 51010 2 P.M. EDT Weather: Clear Temperature: 63F, Dew point: 39F, Wind: NE at 12 kts Sea-level pressure: 30.11 inches Hg, steady Visibility: 35 miles, hazy 6-hourly max.temp: 70F BHO SA 1755 CLR 35 195/63/39/0412/011/ HAZY/ 50000 10070 20062 WEATHER SUMMARY FOR FRIDAY, APRIL 18 TEMPERATURE (DEGREES F) MAX.....72 NORMAL.....56 MIN.....40 NORMAL.....38 MEAN....56 NORMAL.....47 DEPARTURE FROM 30-YEAR NORMAL...........+9 TOTAL DEPARTURE FOR THE MONTH..........+33 [+1.6 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............9 DEPARTURE....... -9 TOTAL HEATING UNITS FOR THE MONTH...........342 DEPARTURE.......-33 TOTAL HEATING UNITS FOR THE SEASON.........5479 DEPARTURE......-360 TOTAL HEATING UNITS LAST SEASON TO DATE....5481 DIFFERENCE.......-2 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY............23 NW AT 6:21 A.M. AEROVANE.............21 NNW AT 7:07 A.M. * ASOS.................21 ENE AT 11:56 A.M. DAVIS................21 NNW AT 3:01 A.M. FASTEST MILE FOR YESTERDAY..............18 NW AT 6:24 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...........17 N AT 6:59 A.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..........19 NW AT 3:03 A.M. AVERAGE WIND SPEED AND DIRECTION......10.5 NE ASOS................9.6 DAVIS..............10.3 N [003 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 THE MONTH..........1.52 DEPARTURE......-1.16 ASOS..............1.66 TOTAL PRECIPITATION FOR THE YEAR..........19.12 DEPARTURE......+2.81 ASOS.............21.54 # # Includes erroneous ASOS precipitation data on 2/13/08. SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE......-0.1 TOTAL SNOWFALL FOR APRIL...................0.0 DEPARTURE......-1.9 TOTAL SNOWFALL FOR THE SEASON.............66.5 DEPARTURE......+7.6 PRELIMINARY CLIMATE SUMMARY FOR APRIL 2008 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane recording wind system when significant TSTM: Thunderstorm day ....: Data not yet available, records not finalized 4/1 59/50/55/+14/0.20/0/000/00 54 S Aero 58 MPH SSW 4/2 47/31/39/-3/0/0/745/97 52 W Aero 51 MPH W 4/3 52/27/40/-2/0/0/648/84 37 SSW 4/4 43/34/39/-3/0.71/0/000/00 35 E 4/5 51/37/44/+1/0.06/0/093/12 21 W 4/6 40/36/38/-5/0.09/0/000/00 36 NE 4/7 39/34/37/-6/0/0/172/22 35 NE Aero 36 MPH NE 4/8 47/30/39/-5/0/0/627/80 22 NE 4/9 59/33/47/+3/0/0/150/19 29 S 4/10 71/44/58/+14/T/0/624/79 34 W 4/11 54/40/47/+2/0.03/096/13 24 SE 4/12 70/43/57/+12/0.43/0/342/43 40 WNW Aero 42 WNW 4/13 47/34/41/-4/T/0/104/13 30 NW 4/14 53/30/42/-4/0/0/625/78 29 NW 4/15 57/33/45/-1/0/0/803/100 23 SSE 4/16 64/39/52/+6/0/0/806/100 24 SSE 4/17 64/14/53/+6/0/0/810/100 23 NE 4/18 70/42/56/+9/0/0/.../.. 23 NW 4/19 morning low temp. 60F; our normal low is now 38F NEW DAILY RECORDS FOR APRIL 2008 None to date. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 19 HIGH 94 IN 1976 [RECORD FOR MONTH] LOW 21 IN 1890 PRECIP 1.71 IN 1969 SNOWFALL 6.0 IN. IN 1887 PEAK GUST 66 MPH E IN 1984 RECORDS FOR APRIL 20 HIGH 88 IN 1927 LOW 18 IN 1897 PRECIP 1.14 IN 1972 SNOWFALL 2.5 IN. IN 1904, 1972 PEAK GUST 76 MPH WNW IN 1963 TODAY'S REPORT PREPARED By: Mike Iacono