BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA SATURDAY, MAY 8, 2021 ALL TIMES ARE IN EASTERN STANDARD TIME SUNRISE: 0430E SUNSET:  1850E MOSTLY CLOUDY WITH GOOD VISIBILITY ATOP GREAT BLUE HILL.... Today was overcast with surprisingly great visibility. We had a mix of low and mid-level cloud cover with an average visibility of 80 miles. Wind is northeasterly and light with a max gust of 20 mph. This provides a chilly breeze off the water, contributing to lower than normal temperatures. The high so far today is 53F, this is 11 degrees below the normal high of 64F. The low since midnight is 40F, which is 5 degrees below the daily normal low of 45F. PRELIMINARY STATS FOR APRIL 2021 TEMPERATURE, Deg. F Avg. Max. 57.2 [+1.5] Avg. Min. 37.8 [+0.1] Mean      47.5 [+0.8] 24-hour corrected mean: 47.0 Max. for month: 75F on the 10th Min. for month: 23F on the 3rd HEATING DEGREE DAYS Total heating units:    519 [-32] Total for the season:  5341 [-694] Total for last season: 5521 PRECIPITATION, Inches Total: 4.89 [+0.45] Greatest in 24 hrs: N/A SNOWFALL, Inches Total: 3.6 [+0.6] Greatest in 24 hrs: 3.6 ins. on the 16th WIND, mph Avg. uncorrected wind speed: 12.1 mph Avg. corrected wind speed:   12.5 mph Prevailing wind direction:   WNW [16%] Peak gust and direction:     58 WNW on the 30th SUNSHINE: Campbell-Stokes card minutes: N/A Astronomical total minutes: N/A Today's Observations: 7 A.M. Weather: Broken stratocumulus and overcast altocumulus Temperature: 45F; Dew Point: 34F; Relative Humidity: 65% Wind: N at 5G16 kts Sea-level pressure: 29.85 in Hg, rising, then more steadily Visibility: 65 miles 6-hr Max temp: 45F 6-hr Min temp: 40F 24-hr Precip: 0.00 ins. 24-hr Snow: 0.0 ins. Snow Depth: 0.0 ins. BHO SA 1155 40 BKN 70 OVC 65 107/45/34/0105G16/985/ 8/87/ 53004 10045 20040 10 A.M. Weather: Broken stratocumulus and overcast altocumulus Temperature: 48F; Dew Point: 37F; Relative Humidity: 65% Wind: NE @ 8 kts Sea-level pressure: 29.89 in Hg; rising steadily Visibility: 75 miles 3-hr Precip: 0.00 ins. 3-hr Snow: 0.0 ins. BHO SA 1455 40 BKN 70 OVC 75 121/48/37/0508/989/ 8/87/ 53014 1 P.M. Weather: Broken stratocumulus and overcast altocumulus Temperature: 52F, Dew point: 34F; Relative Humidity: 49% Wind: NE @ 8 kts   Sea-level pressure: 29.85 in Hg; falling, then steady Visibility: 80 miles 6-hr Max temp: 53F 6-hr Min temp: 45F 6-hr Precip: 0.00 ins. 6-hr Snow: 0.0 ins. Snow Depth: 0 ins. BHO SA 1755 40 BKN 90 OVC 80 109/52/34/0408/985/ 8/87/ 57012 10053 20045 SUMMARY FOR FRIDAY, MAY 7, 2021 TEMPERATURE (DEGREES F) MAX.......61     NORMAL.....64 MIN.......43     NORMAL.....45 MEAN......52     NORMAL.....55 DEPARTURE FROM 30-YEAR (1981-2010) NORMAL........ -3 TOTAL DEPARTURE FOR THE MONTH.....................-6 [-1.1 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL THRU JUN) TOTAL HEATING UNITS FOR YESTERDAY...............13  DEPARTURE.......+3 TOTAL HEATING UNITS FOR THE MONTH...............85  DEPARTURE.......+3 TOTAL HEATING UNITS FOR THE SEASON............5426  DEPARTURE.....-691 TOTAL HEATING UNITS LAST SEASON TO DATE.......5590  DEPARTURE.....-164 COOLING DEGREE DAYS (SEASON JAN THRU DEC) TOTAL COOLING UNITS FOR YESTERDAY............... 0  DEPARTURE....... 0 TOTAL COOLING UNITS FOR THE MONTH............... 0  DEPARTURE.......-2 TOTAL COOLING UNITS FOR THE SEASON.............. 0  DEPARTURE.......-4 TOTAL COOLING UNITS LAST SEASON TO DATE......... 2  DEPARTURE.......-2 PEAK WIND GUST (MPH):                      420C/Official..............28 ESE @ 11:18 A.M.                      AEROVANE (south tower).....22 ESE @ 11:22 A.M.                      ASOS.......................25 ESE @ 11:21 A.M.                      DAVIS #1...................26 ESE @ 11:21 A.M.                      DAVIS #2 (south tower).....25 E   @ 11:05 A.M.                      RMY........................26     @ 11:19 A.M.                      VECTOR.....................27     @ 11:20 A.M.                      MERLIN.....................24 FASTEST MILE: CONTACTING ANEMOMETER/OFFICIAL..................17 ESE @ 11:28 A.M. MAXIMUM 2-MINUTE ASOS AVERAGE...................17 E   @ 11:42 A.M. MAXIMUM 2-MINUTE DAVIS #1 AVERAGE...............19 ESE @ 11:22 A.M. MAXIMUM 2-MINUTE DAVIS #2 AVERAGE...............18 E   @ 10:50 A.M. MAXIMUM 2-MINUTE RMY AVERAGE....................18 SE  @ 11:39 A.M. MAXIMUM 2-MINUTE VECTOR AVERAGE.................19     @ 11:20 A.M. AVERAGE WIND SPEED AND DIRECTION:                      CONTACTING/OFFICIAL...... 10.1 ESE [243 total miles]                      ASOS..................... 10.2                      DAVIS #1................. 10.7 E                      DAVIS #2................. 10.4 E                      RMY...................... 10.1 ESE                      VECTOR................... 10.5 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.............1.39  DEPARTURE....+0.52                              ASOS.............1.35 TOTAL PRECIPITATION FOR THE YEAR.............16.45  DEPARTURE....-2.97                               ASOS...........16.63 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   62/38/50/-3/0.06/0.0/.../..       31 WNW  AERO 35 WNW  RMY 40 05/02   76/48/62/+9/0.01/0.0/.../..       41 SW   AERO 41 SW   RMY 46 05/03   67/48/58/+5/0.07/0.0/.../..       21 E    AERO 20 E    RMY 20 05/04   50/44/47/-7/..../0.0/.../..       36 NNE  AERO 32 NNE  RMY 37 05/05   48/44/46/-8/..../0.0/.../..       18 ESE  AERO 14 ESE  RMY 17 05/06   64/45/55/+1/0.00/0.0/.../..       33 NW   AERO 38 NNW  RMY 39 05/07   61/43/52/-3/0.00/0.0/.../..       28 ESE  AERO 22 ESE  RMY 26 05/08 The low since midnight is 40F, the daily normal low is 45F   DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated) 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 RECORDS FOR MAY 9 HIGH 93F IN 2000 LOW 31F IN 1947 PRECIP 2.72 INCHES IN 1954 SNOWFALL 5.0 INS IN 1977 (RECORD FOR MAY) PEAK GUST 70e MPH NE IN 1977 TODAY'S REPORT PREPARED BY: Benjamin Turner