BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY MONDAY, MAY 18, 2020 ALL TIMES ARE IN EASTERN STANDARD TIME OVERCAST AND COOL WITH LIGHT ONSHORE WIND.... It's been a quiet day today under cloudy skies. A few very light rain showers moved through this morning, but only amounted to a trace. Otherwise a light wind that started out of the west, gradually veered to the northeast helping to keep temperatures on the cool side. Visibility has been limited to only 50 miles today. The high so far today is 58F, this is 9 degrees below the daily normal high of 67F. The low since midnight is 49F, which is a degree above the daily normal low of 48F. Today's Observations: 7 A.M. Weather: Overcast altostratus Temperature: 55F; Dew Point: 46F; Relative Humidity: 72% Wind: N at 8 kts   Sea-level pressure: 30.21 ins. Hg: rising, then more slowly Visibility: 50 miles 6-hr Max temp: 55F 6-hr Min temp: 49F 24-hr Precip:  0.00 ins. 24-hr Snowfall: 0.0 ins. BHO SA 1155 E90 OVC 50 231/55/46/3508/021/ FEW BINOVC SE-S/ 8/02/ 51009 10055 20049 10 A.M. Weather: Overcast altostratus Temperature: 53F; Dew Point: 44F; Relative Humidity: 70% Wind: NE at 8G14 kts Sea-level pressure: 30.22 ins. Hg: steady, then rising Visibility: 50 miles 3-hr Precip: Trace 3-hr Snowfall: 0.0 ins. BHO SA 1455 E85 OVC 50RW- 234/53/44/0508G14/022/ PCPN VRY LGT RB20/ 8/02/ 53003 6000 1 P.M. Weather: Broken altostratus, overcast dense cirrus, few breaks in overcast distant NNW-NE Temperature: 58F; Dew Point: 42F; Relative Humidity: 55% Wind: NE at 7 kts Sea-level pressure: 30.22 ins. Hg: rising then falling Visibility: 50 miles 6-hr Max temp: 58F 6-hr Min temp: 53F 6-hr Precip: Trace 6-hr Snowfall: 0.0 ins. BHO SA 1755 E130 BKN 180 OVC 50 234/58/42/0507/022/ FEW BINOVC DSNT NNW-NE/ 8/022 58000 10058 20053 SUMMARY FOR SUNDAY, MAY 17, 2020 TEMPERATURE (DEGREES F) MAX.....67   NORMAL.....67 MIN.....47   NORMAL.....48 MEAN....57   NORMAL.....57 DEPARTURE FROM 30-YEAR NORMAL................... 0 TOTAL DEPARTURE FOR THE MONTH..................-37 [-2.4 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY............... 8  DEPARTURE........ 0 TOTAL HEATING UNITS FOR THE MONTH..............207  DEPARTURE.......+30 TOTAL HEATING UNITS FOR THE SEASON............5728  DEPARTURE......-484 TOTAL HEATING UNITS LAST SEASON TO DATE.......6140  DEPARTURE......-412 COOLING DEGREE DAYS (SEASON JAN TO DEC) TOTAL COOLING UNITS FOR YESTERDAY................0  DEPARTURE........-1 TOTAL COOLING UNITS FOR THE MONTH................2  DEPARTURE........-5 TOTAL COOLING UNITS FOR THE SEASON...............2  DEPARTURE........-7 TOTAL COOLING UNITS LAST SEASON TO DATE..........0  DEPARTURE........+2 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY....................22 S   AT  8:27 P.M.                      AERO.........................MM MMM AT MM:MM M.M.                     ASOS.........................21 S   AT  8:46 P.M.                    DAVIS........................21 S   AT  5:41 P.M. RMY 21 FASTEST MILE FOR YESTERDAY......................15 S   AT  8:48 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...................16 S   AT  8:49 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..................15 S   AT  7:59 P.M. AVERAGE WIND SPEED AND DIRECTION................ 8.0 SSW                                  ASOS......................... 8.3                    DAVIS........................ 7.8 SSW [203 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..........2.55  DEPARTURE......+0.47                          ASOS..............2.54 TOTAL PRECIPITATION FOR THE YEAR..........19.59  DEPARTURE......-1.04                          ASOS.............20.04 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..............31.9  DEPARTURE......-30.8 PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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 M:    Missing data 05/01  64/52/58/+5/..../0.0/000/00         46 SSE  AERO 44 SSE RMY N/A 05/02  70/42/56/+3/..../0.0/729/86         41 NW   AERO 40 NW  RMY N/A 05/03  78/55/67/+14/0.00/0.0/613/72        35 SSW  AERO 35 SSW RMY 36 05/04  72/45/59/+5/T/0.0/247/29            37 NW   AERO 40 WNW RMY 39   05/05  60/40/50/-4/0.00/0.0/821/96         31 NW   AERO 32 NW  RMY N/A 05/06  57/38/48/-6/T/0.0/498/58            24 ESE  AERO 22 ENE RMY 22 05/07  63/37/50/-5/0.00/0.0/576/67         30 WSW  AERO 29 WSW RMY N/A 05/08  57/40/49/-6/..../0.0/328/38         31 W    AERO 32 W   RMY N/A 05/09  44/32/38/-17/..../T/484/56          52 W    AERO 53 W   RMY 54 05/10  59/31/45/-10/0.00/0.0/763/88        46 W    AERO 46 W   RMY 49 05/11  65/43/54/-2/0.22/0.0/.../..         39 S    AERO 43 S   RMY 41 05/12  55/37/46/-10/0.00/0.0/.../..        37 W    AERO 37 W   RMY 37 05/13  59/32/46/-10/0.00/0.0/.../..        37 WNW  AERO 37 WNW RMY 38 05/14  70/40/55/-2/0.00/0.0/.../..         29 W    AERO 26 W   RMY 27 05/15  78/50/64/+7/..../0.0/.../..         40 WSW  AERO 40 WSW RMY 43 05/16  69/47/58/+1/..../0.0/.../..         31 NW   AERO 31 NW  RMY 32 05/17  67/47/57/0/0.00/0.0/.../..          22 SSW  AERO N/A    RMY 21 05/18 The low since midnight is 49F, the daily normal low is 48F   DAILY RECORDS FOR MAY 2020 5/13/2020: NEW RECORD LOW OF 32F, REPLACING 35F SET IN 1914 AND 2005 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR MAY 18 HIGH 96F IN 2017(RECORD FOR MAY) LOW 35F IN 2002 PRECIP 1.93 INS IN 2007 SNOW TRACE IN 2002 (Ice pellets) PEAK GUST 64 MPH SSW IN 2000 RECORDS FOR MAY 19 HIGH 91F IN 1962 LOW 34F IN 2002 PRECIP 1.54 INCHES IN 1900 PEAK GUST 58 MPH NW IN 1964 TODAY'S REPORT PREPARED BY: Matt Douglas