BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY SATURDAY, MAY 4, 2019 ALL TIMES ARE IN EASTERN STANDARD TIME FOGGY MORNING WITH INTERMITTENT SHOWERS AND INCREASING VISIBILITY IN THE AFTERNOON.... This morning started with 1/8th mile visibility that  increased to a mile at 10 A.M. EST, and finally 40  miles by the 1 o'clock P.M. EST observation. Intermittent showers were experienced at the observatory, with a total rainfall amount of 0.12 inches in the past 24 hours. Fog  was present all morning, and lifted at noon, allowing for the large increase in visibility between 10 and 1. Our high so far today is 52F, 11 degrees below our normal daily maximum temperature of 63F.    PRELIMINARY STATS FOR APRIL 2019 TEMPERATURE, Deg. F Avg. Max. 57.2 [+1.5] Avg. Min. 39.3 [+1.6] Mean      48.3 [+1.6] 24-hour corrected mean: 48.5 Max. for month: 71F on the 13th, 14th, and 19th Min. for month: 27F on the 2nd and 5th HEATING DEGREE DAYS Total heating units:    496 [-55] Total for the season:  5901 [-134] Total for last season: 5693 PRECIPITATION, Inches Total: 8.14 [+3.59] Greatest in 24 hrs: N/A SNOWFALL, Inches Total: Trace [-3.0] Greatest in 24 hrs: N/A  WIND, mph Avg. uncorrected wind speed: 13.2 Avg. corrected wind speed: 13.6 Prevailing wind direction: S at 15% Peak gust and direction: 54 W on 3rd   SUNSHINE: Campbell-Stokes card minutes: N/A Astronomical total minutes:   N/A 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 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 is now 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) 2.57 on April 22, 2019 5) 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: Fog Temperature: 46F; Dew Point: 46F; Wind: NE at 3 kts Sea-level pressure: 29.92 ins. Hg, falling then rising Visibility: 1/8 mile, fog 6-hr Max temp: 51F 6-hr Min temp: 46F 24-hr Precip: 0.10 ins.  24-hr snowfall: 0.0 ins. Snow depth: 0 ins.  BHO SA 1155 W3 X 1/8F 131/46/46/0506/992/ 8//// 53002 70010  10051 20046 10 A.M. Weather: Overcast stratus, fog Temperature: 48F; Dew Point: 48F; Wind: ENE at 5 kts Wind: light Sea-level pressure: 29.92 ins. Hg, rising then falling Visibility: 1 mile, fog 3-hr Precip: 0.02 ins.  BHO SA 1455 E005 OVC 1 132/49/49/0605/992/ FOG WND LGT/ 8/6//  50001 6002/ 1 P.M. Weather: Overcast altostratus, scattered stratus Temperature: 52F; Dew Point: 48F; Wind: ENE at 6 kts Sea-level pressure: 29.90 ins. Hg, falling then more quickly Visibility: 40 miles, distant haze in all directions 6-hr Max temp: 52F 6-hr Min temp: 46F 6-hr Precip: 0.00 ins.  BHO SA 1755 E070 OVC 036 SCT 40 126/52/48/0606/990/ FEW AC S-N DSNT HZ ALQDS 8/61/ 58006 6002/ 10052 20046 SUMMARY FOR FRIDAY, MAY 3, 2019  TEMPERATURE (DEGREES F) MAX.....60   NORMAL.....63 MIN.....43   NORMAL.....44 MEAN....52   NORMAL.....53 DEPARTURE FROM 30-YEAR NORMAL........................-1 TOTAL DEPARTURE FOR THE MONTH.......................-15 [-5.2 DEGREES/DAY] HEATING DEGREE DAYS (SEASON JUL TO JUN) TOTAL HEATING UNITS FOR YESTERDAY..............13   DEPARTURE.........+1 TOTAL HEATING UNITS FOR THE MONTH..............51   DEPARTURE.........14 TOTAL HEATING UNITS FOR THE SEASON...........5952   DEPARTURE.......-120 TOTAL HEATING UNITS LAST SEASON TO DATE......5706   DIFFERENCE......+246 PEAK GUST AND AVERAGE WIND SPEED (MPH)  PEAK WIND GUST FOR YESTERDAY....................23 S  AT 3:16 P.M.                    AERO.........................23 S  AT 3:25 P.M.                    ASOS.........................22 SW AT 3:16 P.M.                     DAVIS........................29 S  AT 3:16 P.M.  RMY 22 FASTEST MILE FOR YESTERDAY......................17 S  AT 3:22 P.M.  MAXIMUM 2-MINUTE ASOS AVERAGE...................17 S  AT 3:16 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE..................17 S  AT 5:04 P.M. AVERAGE WIND SPEED AND DIRECTION...............5.8 SSE                    ASOS........................5.8                    DAVIS.......................6.3 SSE [158 deg.] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.10  DEPARTURE.......-0.03                          ASOS..............0.10 TOTAL PRECIPITATION FOR THE MONTH..........0.12  DEPARTURE.......-0.25                          ASOS..............0.12 TOTAL PRECIPITATION FOR THE YEAR..........21.30  DEPARTURE.......+2.38                          ASOS.............21.33 SNOWFALL (INCHES) THROUGH THIS MORNING (EST) TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0  DEPARTURE.........0.0 TOTAL SNOWFALL FOR THE MONTH...............0.0  DEPARTURE.........0.0 TOTAL SNOWFALL FOR THE SEASON.............47.6  DEPARTURE.......-15.1 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 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/.../..           46 W   AERO 44 W   RMY 44  04/17 62/36/49/+2/0.00/0.0/.../..           26 ESE AERO 25 S   RMY 28 04/18 63/39/51/+3/0.00/0.0/.../..           44 S   AERO 44 S   RMY 50 04/19 71/58/65/+17/..../0.0/.../..          47 SSW AERO 51 SSW RMY 52 04/20 68/60/64/+15/..../0.0/.../..          50 SSW AERO 54 SSW RMY 52 04/21 68/51/60/+11/..../0.0/.../..          35 S   AERO 35 S   RMY N/A 04/22 53/45/49/0/..../0.0/.../..            35 NNE AERO 32 NNE RMY 35 04/23 52/44/48/-2/..../0.0/.../..           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 48/40/44/-8/0.17/0.0/.../..           26 NW  AERO 23 NW  RMY 25 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 57/40/49/-4/0.00/0.0/.../..         21 S  AERO 21 SSE  RMY 21 05/02 45/41/43/-10/0.02/0.0/.../..        21 NE AERO 21 SSW  RMY 20 05/03 60/43/52/-1/..../.../.../..         23 S  AERO 23 S    RMY 22 05/04 Low temp since midnight is 46F; normal low is 44F DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR MAY 4 HIGH 90F IN 2001 LOW 27F IN 1911 (RECORD FOR MAY) PRECIP 1.92 INCHES IN 1893 SNOWFALL 0.1 INCHES IN 1920 PEAK GUST 60 MPH NW IN 1966 RECORDS FOR MAY 5 HIGH 92F IN 1949 LOW 30F IN 1891 PRECIP 2.74 INCHES IN 1922 SNOWFALL 3.0 INCHES IN 1917 PEAK GUST 58 MPH S IN 1966 & 58e MPH SW IN 1976 TODAY'S REPORT PREPARED BY: Samantha Richard