BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 9, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME FIRST RAINFALL SINCE APRIL 25 TOTALS 0.62 INCH The showers which began yesterday morning included a thunder storm late last night with about a quarteer inch of rain in one hour. Rain ended at 1:30 P.M. early this afternoon and the total rainfall for the two days was 0.62 inch. Today's observations: 7 A.M. Weather: Obscurement with fog, very light drizzle occurring Temperature: 58F; Dew Point: 58F; Wind: ENE at 2 kts, estimated, Wind: Light Sea-level pressure: 30.01 ins. Hg, rising slightly Visibility: 1/16 variable to 1/8 mile in very light drizzle and dense fog 6-hour min. temp: 57F 24-hour precip: 0.44 inch BHO SA 1155 W3 X 1/16VL-F 161/58/58/E0702/001/ VSBY 1/16V1/8 PCPN VRY LGT WND LGT/ 8//// 51003 MANUAL 6000/ MANUAL 70044 ASOS 70042 10059 20057 10 A.M. Weather: Obscurement with heavy fog Temperature: 59F; Dew Point: 59F; Wind: ENE at 2 kts, estimated, Wind: Light Sea-level pressure: 30.00 ins. Hg, falling slightly Visibility: 1/8 mile in dense fog 3-hourly precip: 0.04 in. BHO SA 1455 W3 X 1/8F 159/59/59/E0702/000/ WND LGT/ 8//// 58002 MANUAL 6004/ ASOS 60004 1 P.M. Weather: Scattered cumulonibus, scattered stratus fractus, scattered altocumulus lenticularis, scattered dense cirrus anvil top from cumulonimbus, broken cirrus, dark sky distant N-ESE cumulonimbus N-ESE moving moving NNE Temperature: 63F; Dew Point: 60F; Wind: NE at 4 kts, Wind: Light Sea-level pressure: 29.96 ins. Hg, falling then more rapidly Visibility: 6 miles, fog, visbility 25 miles SSE-SW 6-hour max. temp: 63F 6-hour precip: 0.18 in. BHO SA 1755 5 SCT 150 SCT 200 SCT E220 BKN 6F 146/63/60/0505/996/ CB AND DRK XTDNG DSNT N-ESE MOVG NNE STRA DRFTG AT/BLO SMT LVL ALQDS FEW ACSL DARK N-ESE VSBY SSE-SW 25 WNW-E 5 RE35/ 8/943 58013 ASOS 60017 MANUAL 6018/ 10063 20058 WEATHER SUMMARY FOR WEDNESDAY, MAY 8, 2013 TEMPERATURE (DEGREES F) MAX.....71 NORMAL.....64 MIN.....55 NORMAL.....45 MEAN....63 NORMAL.....55 DEPARTURE FROM 30-YEAR NORMAL....................+8 TOTAL DEPARTURE FOR THE MONTH....................+8 [+0.8 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............2 DEPARTURE..........-9 TOTAL HEATING UNITS FOR THE MONTH............81 DEPARTURE.........-12 TOTAL HEATING UNITS FOR THE SEASON.........5603 DEPARTURE........-524 TOTAL HEATING UNITS LAST SEASON TO DATE....4827 DIFFERENCE.......+776 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............31 SSE AT 1:20 P.M. AERO....................35 SSE AT 1:20 P.M. ASOS....................33 SSE AT 1:20 P.M. DAVIS...................34 SSE AT 1:22 P.M. RMY: 35 THE FASTEST MILE FOR YESTERDAY.............26 SSE AT 1:21 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..............25 SSE AT 1:22 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............26 SE AT 1:21 P.M. AVERAGE WIND SPEED AND DIRECTION.........10.1 SE ASOS...................9.6 DAVIS..................9.6 SE [140 deg] PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.44 DEPARTURE...........+0.32 ASOS..............0.42 TOTAL PRECIPITATION FOR THE MONTH..........0.44 DEPARTURE...........-0.55 ASOS..............0.00 TOTAL PRECIPITATION FOR THE YEAR..........16.82 DEPARTURE...........-2.72 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals 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.............99.0 DEPARTURE...........+36.3 PRELIMINARY CLIMATE SUMMARY FOR MAY 2013 CALENDAR DAY DATA DATA REPORTED: DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST AERO: Aerovane wind recording system gust RMY: RMY = R.M. Young wind gust recording system added 8/9/2011 TSTM: Thunderstorm day (thunder heard some time during day) ....: Data not yet available, records not finalized 5/1 67/45/56/+3/0.00/845/100 18 E AERO 16 MPH E RMY 17 5/2 75/43/59/+6/T/669/79 29 NE AERO 26 MPH NE RMY 29 5/3 54/42/48/-5/0.00/706/83 24 NE AERO 25 MPH NE RMY 28 5/4 55/40/48/-6/0.00/843/99 21 NE AERO 23 MPH NE RMY 23 5/5 58/37/48/-6/0.00/752/88 17 ENE AERO 17 MPH ENE RMY 20 5/6 66/40/53/-1/0.00/.../.. 17 S AERO 18 MPH S RMY 20 5/7 77/50/64/+9/0.00/.../.. 21 S AERO 23 MPH S RMY 25 5/8 71/55/63/+8/..../.../.. 31 SSE AERO MPH SSE RMY 35 TSTM 5/9 morning low temp: 57F; the normal low is now 46F DAILY RECORDS FOR MAY 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): 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 RECORDS FOR MAY 10 HIGH 93F IN 1896 LOW 29F IN 1900 PRE 1.85 INS IN 1998 SNOW 2.8 INS 1977 (7.8 INS TOTAL 5/9-5/10 1977) PEAK GUST 64 MPH S IN 1990 TODAY'S REPORT PREPARED BY: Robert Skilling