BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS 02186 ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, APRIL 17, 2010 ALL TIMES ARE IN EASTERN STANDARD TIME A trace of snow was observed on the summit and in lower areas between 7 and 9AM EDT Friday, but only a trace accumulated on the summit. The storm total rainfall through 1PM EST is 0.61 inch April 16 marked the first day so far this month with temperatures below average. The last below average day was back on March 28. The abundance of warmth this April has pushed temperatures more than 10 degrees above normal. Temperatures hovering in the mid to upper 30s today have provided for another rare below average day. Today's observations: 7 A.M. Weather: Overcast stratus, stratus drifting over summit, light drizzle and fog Temperature: 37F, Dew point: 37F, Wind: ENE at 13G20 kts Sea-level pressure: 29.71 inches Hg, steady Visibility: 1 1/2 miles and increasing, 6-hour minimum temp: 37F 24-hour precipitation: 0.48 inches 24-hour snowfall: Trace BHO SA 1155 –X E3 OVC 11/2L-F 062/37/37/0613G20/971/ STRA DRFTG OVR SMT VSBY INCR/ 8/6// 55003 MANUAL 60XXX/ ASOS 60007 MANUAL 70048 ASOS 70044 10038 20037 10 A.M. Weather: Overcast stratus, stratus drifting over summit, moderate drizzle and fog Temperature: 38F, Dew point: 38F, Wind: NE at 8 kts Sea-level pressure: 29.74 inches Hg, rising Visibility: 1/2 mile, varying between 1/8 and 1 mile, 3-hour precipitation: 0.03 ins. BHO SA 1455 –X E2 OVC 1/2VLF 070/38/38/0408/974/ STRA DRFTG OVR SMT VSBY 1/8V1/ 8/6// 51008 MANUAL 60003/ ASOS 60002 1 P.M. Weather: Overcast stratocumulus, few stratus fractus, higher clouds visible, rain shower north moving east-northeast, light rain shower and light drizzle, precipitation very light Temperature: 39F, Dew point: 38F, Wind: NNE at 6 kts Sea-level pressure: 29.74 inches Hg, steady Visibility: 20 miles, 12 miles northwest thru east, 6-hour maximum temp: 40F 6-hour precipitation: 0.03 ins. BHO SA 1755 E6 OVC 20RW-L- 070/39/38/0206/974/ FEW STFRA HIER CLDS VSBL VSBY NW-E 12 RW N MVNG ENE PCPN VRY LGT/ 8/72/ 55000 MANUAL 60003/ ASOS 60003 10040 20037 WEATHER SUMMARY FOR FRIDAY, APRIL 16 TEMPERATURE (DEGREES F) MAX.....43 NORMAL.....56 MIN.....34 NORMAL.....37 MEAN....39 NORMAL.....46 DEPARTURE FROM 30-YEAR AVERAGE................-7 TOTAL DEPARTURE FOR THE MONTH...............+165 (+10.1 DEGREES/DAY) HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............26 DEPARTURE........+7 TOTAL HEATING UNITS FOR THE MONTH...........177 DEPARTURE......-162 TOTAL HEATING UNITS FOR THE SEASON.........5273 DEPARTURE......-530 TOTAL HEATING UNITS LAST SEASON TO DATE....5752 DIFFERENCE.....-479 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY.............26 E AT 10:24 P.M. AEROVANE..............26 E AT 10:24 P.M. ASOS..................26 ESE AT 10:24 P.M. DAVIS.................25 E AT 10:22 P.M. THE FASTEST MILE FOR YESTERDAY...........19 E AT 10:23 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE............18 ESE AT 10:25 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE...........19 E AT 10:23 P.M. AVERAGE WIND SPEED AND DIRECTION.........8.0 E ASOS..................7.7 DAVIS.................7.6 ESE [109 DEG] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.48 DEPARTURE......+0.33 ASOS..............0.44 TOTAL PRECIPITATION FOR THE MONTH..........1.70 DEPARTURE......-0.72 ASOS..............1.66 TOTAL PRECIPITATION FOR THE YEAR..........29.61 DEPARTURE.....+13.56 ASOS.............29.76 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M........Trace DEPARTURE......-0.1 TOTAL SNOWFALL FOR THE MONTH..............Trace DEPARTURE......-1.7 TOTAL SNOWFALL FOR THE SEASON..............64.4 DEPARTURE......+5.8 PRELIMINARY CLIMATE SUMMARY FOR APRIL 2010 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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 4/1 59/43/51/+10/T/0/359/47 24 NNW AERO 30 MPH NNW 4/2 67/46/57/+15/0.00/0/728/95 21 SSE 4/3 75/45/60/+18/0.00/0/731/95 26 SSE 4/4 76/45/61/+19/0.00/0/617/80 27 W AERO 29 MPH W 4/5 72/53/63/+20/0.00/0/635/82 37 SSE AERO 40 MPH SSE 4/6 68/50/59/+16/T/0/202/26 23 W 4/7 90/45/68/+25/0.00/0/578/74 36 WSW AERO 41 MPH WSW 4/8 65/45/55/+11/0.00/0/611/78 31 ENE 4/9 56/37/47/+3/1.12/0/000/00 35 W AERO 39 MPH W 4/10 56/37/47/+3/0.00/0/663/84 45 W AERO 52 MPH W 4/11 69/47/58/+13/0.00/0/506/64 36 W AERO 40 MPH W 4/12 61/43/52/+7/0.00/0/635/80 31 W AERO 33 MPH W 4/13 56/39/48/+3/0.00/0/613/77 23 S 4/14 65/37/51/+5/0.00/0/760/95 28 WNW AERO 32 MPH WNW 4/15 60/40/50/+4/0.00/0/739/92 30 NE 4/16 43/34/39/-7/.../T/000/00 26 E 4/17 our morning low temp: 36F; the normal low is now 38F NEW DAILY RECORDS FOR APRIL 2010 4/4 - new record high maximum temperature of 76F; surpasses 71F in 1950. 4/5 - new record high minimum temperature of 53F; surpasses 52F in 1981 4/7 - new record high maximum temperature of 90F; surpasses 86F in 1929 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 17 HIGH 93 IN 2002 LOW 21 IN 1908 PRECIP 1.68 IN 1954 SNOWFALL 1.0 IN. IN 1899 PEAK GUST 58 MPH NW IN 1994 RECORDS FOR APRIL 18 HIGH 92 IN 1976 LOW 23 1887 PRECIP 1.48 IN 1954 SNOWFALL 3.7 IN. IN 1965 PEAK GUST 59 MPH S IN 1982 TODAY'S REPORT PREPARED BY: Sean Fankhauser/Mike Iacono