BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY FRIDAY, APRIL 12, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME OVERNIGHT SHOWERS AND STEADY RAIN/SLEET BRING 0.42 INCH OF PRECIPITATION; BREEZY AT TIMES WITH TEMPERATURES HANGING IN THE MID 30S Occasional rain showers late last night into early this morning brought 0.21 inch of precipitation to the summit. Steady rain began late this morning and continued into the afternoon. Just before 12:30 P.M. EST, sleet began mixing in with the rain, transitioning to all sleet about 10-15 minutes later. A very light coating of sleet was observed on some surfaces before the sleet transitioned back to light rain shortly after 1 P.M. EST. This latest round of rain and sleet has brought an additional 0.21 inch of precipitation so far, bringing our 3-day total to 0.58 inch. It has been a chilly, raw April day; a day more reminiscent of winter rather than spring. Temperatures are hovering in the mid 30s this afternoon, with a brisk E wind of 15-25 mph with occasional higher gusts. Hard to believe it was 72F and sunny just 3 days ago! Today's observations: 7 A.M. Weather: Scattered cumulus, scattered stratocumulus lenticularis, overcast stratocumulus, cumulus all quadrants except ENE-ESE and overhead, stratocumulus lenticularis SSE-SW, distant haze/thin fog Temperature: 37F; Dew Point: 29F; Wind: E at 16G25 kts, Wind: Peak wind of 29 kts. from the E at 6:14 A.M. EST Wind: Direction variable ENE-ESE Sea-level pressure: 30.14 ins. Hg, falling then rising then falling again Visibility: 35 miles, distant haze/thin fog 24-hr precip: 0.21 inch 6-hour min. temp: 36F BHO SA 1155 25 SCT 30 SCT E40 OVC 35 208/37/29/0916G25/014/ CU ALQDS XCPT ENE-ESE AND OVHD SCSL SSE-SW DSNT HZ/TF PK WND 0829/14 WND 06V12/ 8/8// 57003 ASOS 60008 MANUAL 70021 ASOS 70019 10038 20036 10 A.M. Weather: Light rain, broken stratocumulus, overcast stratocumulus, thin fog/haze all quadrants, mostly very light rain began at 9:38 A.M. EST and continued Temperature: 37F; Dew Point: 32F; Wind: E at 17G25 kts, Wind: Peak wind 33 kts. from the E at 9:06 A.M. EST Wind: Direction variable ENE-SE Sea-level pressure: 30.07 ins. Hg, falling Visibility: 20 miles, E-SW 30 miles, W-NE 15 miles, light rain and thin fog/haze 3-hr precip: Trace BHO SA 1455 E25 BKN 40 OVC 20R- 184/37/32/1017G25/007/ TF/HZ ALQDS VSBY E-SW 30 W-NE 15 PK WND 0933/06 WND 07V13 R-B38 MSTLY VRY LGT CTD/ 8/8// 58024 MANUAL 6000/ 1 P.M. Weather: Light sleet and fog, broken stratocumulus/stratus fractus, overcast nimbostratus, light sleet accumulation on some surfaces, light rain continued from previous hour, light sleet began at 12:28 P.M. EST, light rain ended about 12:40 P.M. EST, light sleet continued Temperature: 34F; Dew Point: 34F; Wind: E at 13G20 kts, Wind: Direction variable ENE-SE Sea-level pressure: 30.01 ins. Hg, falling Visibility: 4 miles, light sleet and fog 6-hr precip: 0.21 inch 6-hr max. temp: 38F 6-hr min. temp: 34F BHO SA 1755 E10 BKN 25 OVC 4IP-F 163/34/34/1013G20/001/ LGT SLEET ACCUM SOME SFCS WND 07V13 R- IP-B28 R-E ABT40 IP- CTD/ 8/72/ 58021 MANUAL 60021 ASOS 60020 10038 20034 WEATHER SUMMARY FOR THURSDAY, APRIL 11 TEMPERATURE (DEGREES F) MAX.....52 NORMAL.....54 MIN.....40 NORMAL.....36 MEAN....46 NORMAL.....45 DEPARTURE FROM 30-YEAR NORMAL....................+1 TOTAL DEPARTURE FOR THE MONTH...................+25 [+2.1 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............19 DEPARTURE..........-1 TOTAL HEATING UNITS FOR THE MONTH...........217 DEPARTURE.........-25 TOTAL HEATING UNITS FOR THE SEASON.........5237 DEPARTURE........-489 TOTAL HEATING UNITS LAST SEASON TO DATE....4501 DIFFERENCE.......+736 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............18 ENE AT 9:32 A.M. AERO....................14 ENE AT 9:32 A.M. ASOS....................20 ENE AT 9:32 A.M. DAVIS...................19 ENE AT 9:32 A.M. RMY: N/A THE FASTEST MILE FOR YESTERDAY.............11 ENE AT 9:48 A.M. * MAXIMUM 2-MINUTE ASOS AVERAGE..............13 E AT 1:01 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............12 ENE AT 11:45 A.M. AVERAGE WIND SPEED AND DIRECTION..........6.0 NE ASOS...................6.8 DAVIS..................5.7 NE [041 deg] *last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.21 DEPARTURE...........+0.04 ASOS..............0.19 TOTAL PRECIPITATION FOR THE MONTH..........0.71 DEPARTURE...........-1.16 ASOS..............0.67 TOTAL PRECIPITATION FOR THE YEAR..........14.80 DEPARTURE...........-1.07 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0 DEPARTURE............-0.2 TOTAL SNOWFALL FOR THE MONTH.............Trace DEPARTURE............-1.8 TOTAL SNOWFALL FOR THE SEASON.............99.0 DEPARTURE...........+37.5 PRELIMINARY CLIMATE SUMMARY FOR APRIL 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 4/1 61/31/46/+5/0.34/0.0/458/60 40 W AERO 44 MPH WNW RMY 46 TSTM 4/2 40/27/34/-7/T/T/460/460/60 45 W AERO 42 MPH W RMY 47 4/3 45/27/36/-6/0.00/0.0/755/98 44 W AERO 43 MPH W RMY 47 4/4 55/26/41/-1/0.00/0.0/719/93 30 WSW AERO 27 MPH WSW RMY 31 4/5 59/36/48/+5/0.00/0.0/403/52 33 NNW AERO 28 MPH NNW RMY 38 4/6 47/30/39/-4/0.00/0.0/747/96 38 NW AERO 35 MPH NW RMY 40 4/7 52/31/42/-1/0.00/0.0/.../.. 51 S AERO 46 MPH S RMY 50 4/8 65/43/54/+10/T/0.0/.../.. 29 SSW AERO 22 MPH SSW RMY N/A 4/9 72/44/58/+14/T/0.0/.../.. 35 WNW AERO 35 MPH WNW RMY 39 TSTM 4/10 64/43/54/+9/0.13/0.0/.../.. 23 SE AERO 20 MPH SE RMY 25 4/11 52/40/46/+1/..../0.0/.../.. 18 ENE AERO 14 MPH ENE RMY N/A 4/12 the morning low temp: 36F; the normal low is now 36F DAILY RECORDS FOR APRIL 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 12 HIGH 82 IN 1945 LOW 17 IN 1926 PRECIP 1.51 IN. IN 1993 SNOWFALL 12.0 IN. IN 1894 PEAK GUST 65e MPH W IN 1978 RECORDS FOR APRIL 13 HIGH 85 IN 1945 LOW 22 IN 1939 PRECIP 2.51 IN. IN 2004 SNOWFALL 6.8 IN. IN 1933 PEAK GUST 59 MPH SSW IN 1995 TODAY'S REPORT PREPARED BY: Sean Fankhauser