BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, APRIL 16, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME TEMPERATURES MODERATING; BRISK SOUTHERLY WINDS GUSTING 30-40 MPH THIS AFTERNOON The morning low started out at the 30-year normal of 38F this morning, but temperatures have warmed nicely into the lower 60s this afternoon. Today will finish a few degrees above normal, breaking our recent 4-day cool streak. Yesterday evening, a warm front moved through the region, shifting the wind direction to southerly. Those southerly winds continue today, and have increased in speed. This afternoon, winds are frequently gusting in the 30-40 mph range. Along with a warmer air mass, the strong southerly winds are bringing a little more moisture into the region, as evidenced by not only increasing dew point temperatures but also by decreasing visibility today. Clouds have slowly been increasing from the west and northwest today. Today's observations: 7 A.M. Weather: Scattered altocumulus, scattered thin cirrus, altocumulus/ altocumulus lenticularis distant SSW-NW-NNE, cirrus distant N-ENE, thin smoke layer along horizon all quadrants, distant haze Temperature: 44F; Dew Point: 36F; Wind: S at 13G20 kts. Sea-level pressure: 30.40 ins. Hg, rising then falling Visibility: 65 miles, distant haze 6-hour min. temp: 38F BHO SA 1155 80 SCT 250 –SCT 65 293/44/36/1713G20/040/ AC/ACSL DSNT SSW-NW-NNE CI DSNT N-ENE THN K LYR ALG HRZN ALQDS DSNT HZ/ 8/041 50000 10044 20038 10 A.M. Weather: Scattered altocumulus, scattered thin cirrus, few cumulus/cumulus fractus forming distant SSE-SSW, altocumulus/altocumulus lenticularis SSW-NW-NE, cirrus W-N-E, distant haze Temperature: 57F; Dew Point: 38F; Wind: S at 13G22 kts, Wind: Direction variable SSE-SW Sea-level pressure: 30.37 ins. Hg, falling Visibility: 65 miles, distant haze BHO SA 1455 80 SCT 250 –SCT 65 283/57/38/1913G22/037/ FEW CU/CUFRA FRMG DSNT SSE-SSW AC/ACSL SSW-NW-NE CI W-N-E DSNT HZ WND 15V22/ 8/141 58010 1 P.M. Weather: Scattered altocumulus (2 levels), scattered cirrostratus, broken thin cirrus, few small cumulus fractus distant SSE-SSW, few cumulus distant WSW-NNW, lower altocumulus/altocumulus lenticularis distant W-N, higher altocumulus/altocumulus lenticularis NNE-SE, cirrostratus W-NNE invading, distant haze Temperature: 60F; Dew Point: 40F; Wind: S at 21G28 kts, Wind: Peak wind of 31 kts. from the SSW at 12:09 P.M. Wind: Direction variable SSE-SW Sea-level pressure: 30.28 ins. Hg, falling Visibility: 55 miles, distant haze 6-hour max temp: 62F BHO SA 1755 70 SCT 90 SCT 200 SCT 250 –BKN 55 253/60/40/1821G28/028/ FEW SML CUFRA DSNT SSE-SSW FEW CU DSNT WSW-NNW LWR AC/ACSL DSNT W-N HIER AC/ACSL NNE-SE CS W-NNE INVADING DSNT HZ PK WND 2031/09 WND 16V22/ 8/147 56030 10062 20044 WEATHER SUMMARY FOR MONDAY, APRIL 15 TEMPERATURE (DEGREES F) MAX.....55 NORMAL.....56 MIN.....35 NORMAL.....38 MEAN....45 NORMAL.....47 DEPARTURE FROM 30-YEAR NORMAL....................-2 TOTAL DEPARTURE FOR THE MONTH...................+10 [+0.5 DEGREE/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY............20 DEPARTURE..........+2 TOTAL HEATING UNITS FOR THE MONTH...........309 DEPARTURE.........-10 TOTAL HEATING UNITS FOR THE SEASON.........5329 DEPARTURE........-473 TOTAL HEATING UNITS LAST SEASON TO DATE....4543 DIFFERENCE.......+786 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............21 ESE AT 3:21 P.M. AERO....................15 S AT 9:12 P.M. * ASOS....................22 S AT 9:12 P.M. DAVIS...................21 SSE AT 5:31 P.M. RMY: N/A THE FASTEST MILE FOR YESTERDAY.............16 ESE AT 3:21 P.M. MAXIMUM 2-MINUTE ASOS AVERAGE..............17 S AT 9:12 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............16 S AT 9:12 P.M. AVERAGE WIND SPEED AND DIRECTION..........9.8 SSE ASOS...................9.9 DAVIS..................9.0 E [091 deg] * last of several occurrences... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE...........-0.15 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........1.18 DEPARTURE...........-1.33 ASOS..............1.13 TOTAL PRECIPITATION FOR THE YEAR..........15.27 DEPARTURE...........-1.24 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............-0.1 TOTAL SNOWFALL FOR THE MONTH.............Trace DEPARTURE............-2.2 TOTAL SNOWFALL FOR THE SEASON.............99.0 DEPARTURE...........+37.1 PRELIMINARY CLIMATE SUMMARY FOR APRIL 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 4/1 61/31/46/+5/0.34/0.0/458/60 40 W AERO 44 MPH WNW RMY 46 TSTM 4/2 40/27/34/-7/T/T/460/60 45 W AERO 42 MPH W RMY 47 4/3 45/27/36/-6/0.00/0.0/755/98 44 W AERO 43 MPH W RMY 47 4/4 55/26/41/-1/0.00/0.0/719/93 30 WSW AERO 27 MPH WSW RMY 31 4/5 59/36/48/+5/0.00/0.0/403/52 33 NNW AERO 28 MPH NNW RMY 38 4/6 47/30/39/-4/0.00/0.0/747/96 38 NW AERO 35 MPH NW RMY 40 4/7 52/31/42/-1/0.00/0.0/391/50 51 S AERO 46 MPH S RMY 50 4/8 65/43/54/+10/T/0.0/494/63 29 SSW AERO 22 MPH SSW RMY N/A 4/9 72/44/58/+14/T/0.0/456/58 35 WNW AERO 35 MPH WNW RMY 39 TSTM 4/10 64/43/54/+9/0.13/0.0/426/54 23 SE AERO 20 MPH SE RMY 25 4/11 52/40/46/+1/0.09/0.0/.../.. 18 ENE AERO 14 MPH ENE RMY N/A 4/12 40/34/37/-8/0.58/T/000/00 38 E AERO 32 MPH E RMY 41 4/13 52/34/43/-3/0.04/0.0/128/16 31 NNE AERO 27 MPH NNE RMY 21 4/14 52/36/44/-2/0.00/0.0/216/27 31 WNW AERO 27 MPH WNW RMY 32 4/15 55/35/45/-2/0.00/0.0/.../.. 21 ESE AERO 15 MPH S RMY N/A 4/16 the morning low temp: 38F; the normal low is now 38F DAILY RECORDS FOR APRIL 2013 None so far. DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR APRIL 16 HIGH 89 IN 2012 LOW 23 IN 1943 PRECIP 2.45 IN. IN 1929 SNOWFALL 2.0 IN. IN 1904, 1962 PEAK GUST 73 MPH E IN 2007 RECORDS FOR APRIL 17 HIGH 93 IN 2002 LOW 21 IN 1908 PRECIP 1.68 IN 1954 SNOWFALL 1.0 IN. IN 1899 PEAK GUST 63 MPH ESE IN 2011 TODAY'S REPORT PREPARED BY: Sean Fankhauser