BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, APRIL 9, 2020 ALL TIMES ARE IN EASTERN STANDARD TIME OVERCAST WITH A THUNDERSTORM PASSING BY IN THE AFTERNOON.... Today we observed overcast skies with limited visibility and light rain in the morning hours. Pressure decreased rapidly as the day went on, and by 10 A.M. it was lightly raining. Wind rose with the pressure decrease, reaching speeds up to 40 mph from the southeast. Rainfall was 0.19 inches by 1 P.M., becoming stronger in the following hours. A thunderstorm passed by around 2 P.M., with a flash of lightning around 2:15. Visibility was 10 miles at its highest today, due to a fog that became more significant as the day went on. Our high temperature so far today is 46F, which is 7 degrees below our daily normal high temperature of 53F. The low since midnight is 39F, which is 4 degrees above the daily normal low of 35F. PRELIMINARY STATS FOR MARCH 2020 TEMPERATURE, Deg. F Avg. Max. 49.8 [+5.5] Avg. Min. 32.3 [+5.7] Mean      41.1 [+5.6] 24-hour corrected mean: 40.5 Max. for month: 72F on the 9th Min. for month: 15F on the 1st HEATING DEGREE DAYS Total heating units:    733 [-183] Total for the season:  4873 [-611] Total for last season: 5432 PRECIPITATION, Inches Total: 4.67 [-0.91] Greatest in 24 hrs: N/A SNOWFALL, Inches Total: 2.8 [-9.9] Greatest in 24 hrs: N/A WIND, mph Avg. uncorrected wind speed: 12.6 mph Avg. corrected wind speed:   12.9 mph Prevailing wind direction:   W [12%] Peak gust and direction:     56 W on the 4th SUNSHINE: Campbell-Stokes card minutes: 11298 minutes of possible 21516 or 53% Astronomical total minutes: 11708 minutes of possible 22287 or 53% Today's Observations: 7 A.M. Weather: Overcast altostratus Temperature: 42F; Dew Point: 40F; Relative Humidity: 93% Wind: S at 8 kts Sea-level pressure: 29.56 ins. Hg: falling steadily Visibility: 10 miles, thin fog 6-hr Max temp: 42F 6-hr Min temp: 39F 24-hr Precip:  0.03 ins. 24-hr Snowfall: 0.0 ins. BHO SA 1155 E160 OVC 10R- 006/42/40/1808/955/ THN FG ALQDS/ 8/02/ 70003 58015 10042 20039 10 A.M. Weather: Overcast nimbostratus, light rain Temperature: 45F; Dew Point: 43F; Relative Humidity: 93% Wind: SSE at 19G29 kts, Peak wind: 34 MPH (29 kts) S at 9:49 A.M. Sea-level pressure: 29.41 ins. Hg: falling rapidly Visibility: 10 miles, thin fog 3-hr Precip:  0.01 ins. 3-hr Snowfall: 0.0 ins. BHO SA 1455 E65 OVC 10R- 960/45/43/1619G29/941/ THN FG ALQDS R-CTD PK WND 1729/49/ 8/02/ 6001/ 58046 1 P.M. Weather: Overcast nimbostratus, light rain Temperature: 43F; Dew Point: 43F; Relative Humidity: 100% Wind: SE at 15G24 kts, Peak wind: 34 MPH (29 kts) S at 10:46 A.M. Sea-level pressure: 29.21 ins. Hg: falling rapidly Visibility: 3 miles, fog 6-hr Max temp: 46F 6-hr Min temp: 42F 6-hr Precip:  0.19 ins. 6-hr Snowfall: 0.0 ins. BHO SA 1755 E55 OVC 3R-F 892/43/43/1415G24/921/ R-CTD PRESFR PK WND 1729/1546/ 8/02/ 6019/ 56068 10046 20042 SUMMARY FOR WEDNESDAY, APRIL 8, 2020 TEMPERATURE (DEGREES F) MAX.....50   NORMAL.....53 MIN.....41   NORMAL.....35 MEAN....46   NORMAL.....44 DEPARTURE FROM 30-YEAR NORMAL....................+2 TOTAL DEPARTURE FOR THE MONTH....................+14 [+1.6 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY...............19  DEPARTURE.......-2 TOTAL HEATING UNITS FOR THE MONTH..............167  DEPARTURE.......-14 TOTAL HEATING UNITS FOR THE SEASON............5040  DEPARTURE......-625 TOTAL HEATING UNITS LAST SEASON TO DATE.......5577  DEPARTURE......-537 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY....................22 S   AT  9:36 P.M.                      AERO.........................22 S   AT  9:36 P.M                     ASOS.........................22 S   AT  9:35 P.M.                    DAVIS........................23 S   AT  9:34 P.M. RMY 22 FASTEST MILE FOR YESTERDAY......................17 S   AT 11:00 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE...................17 S   AT 11:00 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..................18 S   AT  9:34 P.M. AVERAGE WIND SPEED AND DIRECTION.............. 8.5 S                                  ASOS....................... 9.0                    DAVIS.......................8.8 ESE [106 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.03  DEPARTURE......-0.13                          ASOS..............0.03 TOTAL PRECIPITATION FOR THE MONTH..........2.80  DEPARTURE......+1.45                          ASOS..............2.88 TOTAL PRECIPITATION FOR THE YEAR..........12.13  DEPARTURE......-3.22                          ASOS.............12.62 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE.......-0.2 TOTAL SNOWFALL FOR THE MONTH................0.0  DEPARTURE.......-1.4 TOTAL SNOWFALL FOR THE SEASON..............27.6  DEPARTURE......-33.5 PRELIMINARY CLIMATE SUMMARY FOR MARCH 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 03/01  33/15/24/-7/0.00/0.0/676/100        28 WNW AERO 28 WNW RMY 27 03/02  52/24/38/+7/T/T/482/71              40 S   AERO 39 S   RMY 41 03/03  64/45/55/+23/..../0.0/361/53        30 S   AERO 30 S   RMY N/A 03/04  50/38/44/+12/..../0.0/561/82        56 W   AERO 56 W   RMY 58 03/05  51/32/42/+10/0.00/0.0/666/97        31 W   AERO 31 NW  RMY 32 03/06  47/30/39/+7/..../.../283/41         46 NE  AERO 45 NE  RMY 46 03/07  43/26/35/+2/..../.../534/77         42 N   AERO 43 N   RMY 44 03/08  53/26/40/+7/0.00/0.0/508/73         31 W   AERO 30 W   RMY 28 03/09  72/40/56/+23/0.00/0.0/685/98        32 SW  AERO 32 SW  RMY 31 03/10  68/49/59/+26/0.00/0.0/246/35        48 WSW AERO 46 WSW RMY 49 03/11  56/37/47/+13/0.00/0.0/501/71        31 WNW AERO M  M   RMY 21 03/12  46/31/39/+5/..../0.0/156/22         21 SE  AERO 18 SE  RMY N/A 03/13  59/38/49/+15/..../0.0/000/00        46 WNW AERO 44 WNW RMY 46 03/14  51/35/43/+8/0.00/0.0/613/86         37 W   AERO 36 W   RMY 35 03/15  47/28/38/+3/0.00/0.0/680/95         28 NW  AERO 28 NW  RMY N/A 03/16  36/22/29/-6/0.00/0.0/618/86         21 NE  AERO 21 ESE RMY 21 03/17  43/28/36/0/..../0.4/000/00          29 W   AERO 30 W   RMY 29 03/18  54/31/43/+7/..../0.0/609/84         26 S   AERO 26 S   RMY 26 03/19  43/37/40/+4/..../0.0/000/00         36 E   AERO 35 E   RMY 34 03/20  66/37/52/+15/..../0.0/000/00        48 W   AERO 48 W   RMY 46 03/21  55/29/42/+5/0.00/0.0/535/73         45 W   AERO 48 W   RMY N/A 03/22  36/23/30/-7/0.00/0.0/692/94         23 NE  AERO 24 NE  RMY 23 03/23  40/25/33/-5/..../1.6/037/05         38 NNE AERO 39 NNE RMY 38 03/24  48/33/41/+3/..../.../148/20         37 NNW AERO 37 NNW RMY N/A 03/25  41/35/38/0/0.03/0.0/000/00          28 ENE AERO 28 ENE RMY 27 03/26  51/30/41/+2/..../0.0/613/82         25 SSE AERO 26 SSW RMY N/A 03/27  61/41/51/+12/..../0.0/.../..        32 NW  AERO M  M   RMY 33 03/28  56/36/46/+7/..../0.0/.../..         22 S   AERO 21 E   RMY N/A 03/29  43/37/40/0/..../0.0/.../..          32 NE  AERO 33 NE  RMY 33 03/30  40/34/37/-3/..../0.0/.../..         33 NE  AERO 33 NE  RMY 33 03/31  40/29/35/-6/..../0.0/.../..         28 ENE AERO 26 ENE RMY N/A PRELIMINARY CLIMATE SUMMARY FOR APRIL 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 04/01  42/28/35/-6/0.00/0.0/.../..         28 NE  AERO 28 NE  RMY 30 04/02  46/35/41/0/.../0.0/.../..           39 NW  AER0 40 NW  RMY 41 04/03  42/38/40/-2/..../0.0/.../..         48 NE  AERO 53 NE  RMY 49 04/04  46/36/41/-1/..../0.0/.../..         38 NE  AERO 38 NE  RMY N/A 04/05  55/36/46/+3/T/0.0/.../..            22 S   AERO 21 S   RMY 21 04/06  61/40/51/+8/0.00/0.0/.../..         29 NW  AERO 30 NW  RMY 29 04/07  63/42/53/+10/0.00/0.0/.../..        29 W   AERO 30 W   RMY 28 04/08  50/41/46/+2/..../.../.../..         23 S   AERO 22 S   RMY 22 04/09 The low since midnight is 39F, daily normal minimum is 36F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated):   RECORDS FOR APRIL 9 HIGH 83 IN 1991 LOW 18 IN 1888 PRECIP 2.38 IN. IN 1935 SNOWFALL 11.0 IN. IN 1917 PEAK GUST 72 MPH WNW IN 1962 RECORDS FOR APRIL 10 HIGH 83 IN 1922 LOW 20 IN 1985 PRECIP 2.40 IN. IN 1935 SNOWFALL 10.1 IN. IN 1996 PEAK GUST 66 MPH WNW IN 1967 TODAY'S REPORT PREPARED BY: Benjamin Turner