BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, APRIL 30, 2019 ALL TIMES ARE IN EASTERN STANDARD TIME OVERCAST WITH SOME RAIN IN THE MORNING AND LIGHT WINDS THROUGHOUT THE DAY.... We measured 0.17 inches of precipitation from  rainfall earlier this morning. Visibility improved from a mile at 7 A.M. to 20 miles this afternoon. We observed the sun breaking out of the clouds at  the 1 P.M. observation. Wind has been relatively  calm, with an average speed of 3 mph. The high so  far today is 45F, 16 degrees below the daily normal  maximum of 61F. The low since midnight is 40F, three  degrees below the daily normal of 43F.   BHO Greatest April Precipitation, inches (1885-2019): 1) 10.37 in 1987 2)  9.38 in 2004 3)  8.71 in 1929 4)  8.68 in 2007 5)  8.53 in 1904 6)  8.14 in 2019  (through 7 AM on 4/30) 7)  7.57 in 1935     7.57 in 1983 9)  7.31 in 1901 The calendar day rainfall on Monday, 4/22, was more than two and a half inches, which made it one of the wettest calendar days ever observed in April. The finalized amount for the day will be reported when available.   BHO Greatest April Calendar Day Precipitation, inches (1885-2019): 1) 3.47 on April 1,  2004 2) 3.18 on April 21, 1991 3) 2.63 on April 16, 2018 4) 2.51 on April 24, 1898    2.51 on April 13, 2004 6) 2.45 on April 16, 1929 7) 2.41 on April 28, 1904 8) 2.40 on April 10, 1935 Today's Observations: 7 A.M. Weather: Light drizzle, partial obscuration due to fog Temperature: 40F; Dew Point: 40F; Wind: SSE at 4 kts, Wind: Light Sea-level pressure: 30.20 ins. Hg, falling steadily Visibility: 1 mile, fog 6-hr Max temp: 44F 6-hr Min temp: 40F 24-hr Precip: 0.17 ins.  24-hr snowfall: 0.0 ins. Snow depth: 0 ins.  BHO SA 1155 –X 1L-F 228/40/40/1604/020/ L-CTD WND LGT/  8//// 70017 58005 10044 20040  10 A.M. Weather: Overcast altostratus, few stratus fractus Temperature: 43F; Dew Point: 43F; Wind: W at 1 kt, Wind: Light and variable Sea-level pressure: 30.21 ins. Hg, rising steadily Visibility: 20 miles, except 8 miles W-NE 3-hr Precip: Trace BHO SA 1455 E65 OVC 20 230/43/43/E2601/021/ DSNT FG FEW  STFA ALQDS VSBY 8 W-NE WND L/V/ 8/72/ 53002  1 P.M. Weather: Overcast stratus Temperature: 45F; Dew Point: 43F; Wind: NW at 5 kts, Wind: Light Sea-level pressure: 30.24 ins. Hg, rising steadily Visibility: 20 miles, distant fog 6-hr Max temp: 45F 6-hr Min temp: 40F 6-hr Precip: Trace 6-hr snowfall: 0.0 ins.  BHO SA 1755 E15 OVC 20 238/45/43/3205/024/ DSNT FG ALQDS  WND LGT/ 8/6// 600// 53008 10045 20040 SUMMARY FOR MONDAY, APRIL 29, 2019  TEMPERATURE (DEGREES F) MAX.....60   NORMAL.....61 MIN.....34   NORMAL.....43 MEAN....47   NORMAL.....52 DEPARTURE FROM 30-YEAR NORMAL........................-5 TOTAL DEPARTURE FOR THE MONTH.......................+61 [+1.9 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............18   DEPARTURE.........+5 TOTAL HEATING UNITS FOR THE MONTH.............475   DEPARTURE........-63 TOTAL HEATING UNITS FOR THE SEASON...........5880   DEPARTURE.......-142 TOTAL HEATING UNITS LAST SEASON TO DATE......5669   DIFFERENCE......+211 PEAK GUST AND AVERAGE WIND SPEED (MPH)  PEAK WIND GUST FOR YESTERDAY....................23 NW  AT  8:58 A.M.                    AERO.........................24 WNW AT 10:38 A.M.                    ASOS.........................25 NW  AT  9:00 A.M.                     DAVIS........................25 W   AT  8:58 A.M.  RMY 24 FASTEST MILE FOR YESTERDAY......................19 W   AT  2:32 P.M.  MAXIMUM 2-MINUTE ASOS AVERAGE...................17 WNW AT  2:28 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..................19 WSW AT  2:30 P.M. AVERAGE WIND SPEED AND DIRECTION...............9.9 W                    ASOS.......................10.2                    DAVIS......................10.2 WSW [249 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.17  DEPARTURE.......+0.04                          ASOS..............0.16 TOTAL PRECIPITATION FOR THE MONTH..........8.14  DEPARTURE.......+3.72                          ASOS..............8.06 TOTAL PRECIPITATION FOR THE YEAR..........21.18  DEPARTURE.......+2.76                          ASOS.............21.21 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0  DEPARTURE........-0.1 TOTAL SNOWFALL FOR THE MONTH.............TRACE  DEPARTURE........-3.0 TOTAL SNOWFALL FOR THE SEASON.............47.6  DEPARTURE.......-15.1 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 04/01 45/29/37/-4/0.00/0.0/748/98           40 WNW AERO 37 W   RMY 42 04/02 50/27/39/-2/..../0.0/605/79           29 S   AERO 25 S   RMY 31 04/03 62/35/49/+7/..../0.0/484/63           54 W   AERO 58 W   RMY 56 04/04 50/34/42/0/..../0.0/717/93            46 W   AERO 41 W   RMY N/A 04/05 47/27/37/-6/..../0.0/341/44           23 SSW AERO 17 SSW RMY 23 04/06 64/32/48/+5/..../0.0/536/69           24 NW  AERO 18 W   RMY 26 04/07 66/41/54/+11/0.00/0.0/320/41          24 S   AERO 18 S   RMY 25 04/08 48/34/41/-3/0.49/0.0/000/00           25 NE  AERO 20 NE  RMY 26 04/09 40/32/36/-8/0.08/0.0/000/00           23 NE  AERO 16 N   RMY 25 04/10 43/30/37/-8/T/T/000/00                32 NW  AERO 26 NW  RMY 36 04/11 51/29/40/-5/0.00/0.0/403/51           23 NW  AERO 18 NW  RMY N/A 04/12 53/38/46/+1/..../0.0/000/00           35 SSW AERO 29 SSW RMY 39 04/13 71/54/63/+17/..../0.0/167/21          38 SSW AERO 32 SSW RMY N/A 04/14 71/51/61/+15/..../0.0/224/28          25 S   AERO 18 S   RMY N/A 04/15 67/40/54/+7/..../0.0/168/21           46 W   AERO 52 W   RMY 50 04/16 58/37/48/+1/0.00/0.0/805/100          46 W   AERO 44 W   RMY 44  04/17 62/36/49/+2/0.00/0.0/807/100          26 ESE AERO 25 S   RMY 28 04/18 63/39/51/+3/0.00/0.0/000/00           44 S   AERO 44 S   RMY 50 04/19 71/58/65/+17/..../0.0/049/06          47 SSW AERO 51 SSW RMY 52 04/20 68/60/64/+15/..../0.0/000/00          50 SSW AERO 54 SSW RMY 52 04/21 68/51/60/+11/..../0.0/123/15          35 S   AERO 35 S   RMY N/A 04/22 53/45/49/0/..../0.0/000/00            35 NNE AERO 32 NNE RMY 35 04/23 52/44/48/-2/..../0.0/041/05           30 NNE AERO 26 NNE RMY N/A 04/24 65/44/55/+5/..../0.0/.../..           29 WNW AERO 29 WNW RMY 30 04/25 61/39/50/0/0.00/0.0/.../..            22 S   AERO 22 S   RMY 21  04/26 53/42/48/-3/..../0.0/.../..           35 ESE AERO 30 W   RMY 33 04/27 54/39/47/-4/..../.../.../..           41 W   AERO 44 W   RMY 47 04/28 51/38/45/-7/0.08/0.0/.../..           28 W   AERO 28 W   RMY N/A 04/29 60/34/47/-5/0.00/0.0/.../..           23 NW  AERO 24 WNW RMY 24 04/30 Low temp since midnight is 40F; normal low is 43F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 30 HIGH 86 IN 1942 LOW 30 IN 1931 PRECIP 1.41 IN 1991 SNOWFALL 0.3 IN. IN 1909 PEAK GUST 64e MPH NW IN 1978 RECORDS FOR MAY 1 HIGH 87F IN 1899 LOW 29F IN 1978 PRECIP 2.53 INCHES IN 1921 SNOWFALL TRACE IN 1905,1917,1921,1995,2016 PEAK GUST 57 MPH NW IN 1974 TODAY'S REPORT PREPARED BY: Benjamin Turner