BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, MAY 7, 2016 ALL TIMES ARE IN EASTERN STANDARD TIME CLOUDY AND COOL WITH DRIZZLE AND FOG TODAY... The first sunshine of the month occurred on Friday with nearly six hours of sun in total. No sunshine on the first five days of May set a new record for the least sunshine to start May. Clouds returned today with showers overnight bringing a total of 0.13 inches of new rainfall. Light drizzle fell all morning with only a trace of precipitation for the six hours ending at 1 PM EST. A passing rain shower after 1 PM brought a few hundredths of additional rainfall this afternoon. Visibility has been poor today, rising from 1/8 mile earlier this morning to only 1/4-1/2 mile this afternoon. Today's Observations: 7 A.M. Weather: Sky obscured with light drizzle and dense fog Temperature: 44F; Dew Point: 44F; Wind: NE at 12 kts Sea-level pressure: 29.89 ins. Hg, falling, then rising Visibility: 1/8 mile 6-hr Max temp: 44F 6-hr Min temp: 43F 24-hr precip: 0.13 in. BHO SA 1155 W2 X 1/8L-F 121/44/44/0512/989/ 8//// 55004 600// 70013 10044 20043 10 A.M. Weather: Sky obscured with light drizzle and dense fog, stratus drifting over summit Temperature: 45F; Dew Point: 45F; Wind: NE at 10 kts Sea-level pressure: 29.87 ins. Hg, falling, then rising Visibility: 1/8 mile 3-hr precip: Trace BHO SA 1455 W2 X 1/8L-F 116/45/45/0510/987/ STRA DRFTG OVR SMT/ 8//// 55005 6000/ 1 P.M. Weather: Sky obscured with light drizzle and dense fog, stratus drifting over summit Temperature: 57F; Dew Point: 46F; Wind: NE at 4 kts (estimated) Sea-level Pressure: 29.84 ins. HG, falling, then more slowly Visibility: 1/4 mile, variable 1/8 to 1/2 mile 6-hr Max temp: 48F 6-hr Min temp: 44F 6-hr Precip: Trace BHO SA 1755 W3 X 1/4VL-F 104/47/46/E0404/984/ STRA DRFTG OVR SMT VSBY 1/8V1/2/ 8//// 56012 6000/ 10048 20044 SUMMARY FOR FRIDAY, MAY 6, 2016 TEMPERATURE (DEGREES F) MAX.....54 NORMAL.....63 MIN.....43 NORMAL.....45 MEAN....49 NORMAL.....54 DEPARTURE FROM 30-YEAR NORMAL..........................-5 TOTAL DEPARTURE FOR THE MONTH.........................-46 [-7.9 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............16 DEPARTURE..........+5 TOTAL HEATING UNITS FOR THE MONTH.............115 DEPARTURE.........+44 TOTAL HEATING UNITS FOR THE SEASON...........5107 DEPARTURE........-999 TOTAL HEATING UNITS LAST SEASON TO DATE......6314 DIFFERENCE......-1207 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...................28 ENE AT 11:03 A.M. * ASOS........................27 ENE AT 11:03 A.M. DAVIS.......................25 NNW AT 12:27 P.M. RMY 26 FASTEST MILE FOR YESTERDAY.....................19 E AT 12:23 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE..................21 ENE AT 12:55 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.................18 NE AT 12:55 P.M. AVERAGE WIND SPEED AND DIRECTION.............11.9 ENE ASOS......................11.6 DAVIS.....................10.1 NE [043 Deg.] * Last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.13 DEPARTURE......+0.01 ASOS..............0.12 TOTAL PRECIPITATION FOR THE MONTH..........1.45 DEPARTURE......+0.71 ASOS..............1.43 TOTAL PRECIPITATION FOR THE YEAR..........18.39 DEPARTURE......-0.90 ASOS.............18.43 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0 DEPARTURE........0.0 TOTAL SNOWFALL FOR THE MONTH..............TRACE DEPARTURE........0.0 TOTAL SNOWFALL FOR THE SEASON..............57.5 DEPARTURE.......-5.7 PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/ AERO/RMY GUST AERO: Aerovane wind recording system gust RMY: R.M. Young wind gust recording system TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 5/1 52/39/46/-7/.../T/000/00 21 S AERO 22 SE RMY 20 5/2 50/41/46/-7/.../0.0/000/00 20 NE AERO 21 NE RMY 18 5/3 48/43/46/-7/.../0.0/000/00 16 E AERO 16 E RMY 17 5/4 48/41/45/-9/.../0.0/000/00 33 NE AERO 35 NE RMY 34 5/5 44/41/43/-11/.../0.0/000/00 39 NNE AERO 41 NNE RMY 39 5/6 54/43/49/-5/.../0.0/.../.. 28 ENE AERO 29 N RMY 26 5/7 low temp since midnight is 43F; normal low now 45F DAILY RECORDS FOR MAY 2016 5/1/16: DAILY RECORD SNOWFALL OF A TRACE, TIES PREVIOUS RECORDS SET IN 1905, 1917, 1921, and 1995 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 7 HIGH 93F IN 1930 LOW 33F IN 1970 PRECIP 1.19 INCHES IN 2005 SNOWFALL TRACE IN 1967 PEAK GUST 66e MPH WNW IN 1940 RECORDS FOR MAY 8 HIGH 89F IN 2000 LOW 29F IN 1956 PRECIP 1.48 INCHES IN 1886 SNOWFALL TRACE IN 1898, 1947 PEAK GUST 68e MPH NNW IN 1943 TODAY'S REPORT PREPARED BY: Mike Iacono