BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY THURSDAY, MAY 2, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME BEAUTIFUL WARM VERY DRY DAY AHEAD OF APPROACHING BACK-DOOR COLD FRONT--TEMPS. REACH MID 70'S The temperature had reached 75 degrees F by early this afternoon ahead of an approaching back-door cold front. Although the wind had shifted to east there had only been a slight drop in temperature through 2 P.M. EDT. A FEW PRELIMINARY APRIL 2013 MONTHLY STATS Additional stats to come next few days.... Temp: Deg. F Av. Max. 58.1 Av. Min. 38.1 Mean 48.1 [+1.4] Mean temp. corr. to 24 hours: 47.0 Highest 72 on 9th,19th,24th Lowest 26 on 4th Total heating degree day units: 503 [-48 ] Total heating degree days for season: 5523 [-512 ] Precipitation in inches Total for April: 2.29 Departure from normal: -2.26 Snowfall: trace Departure from normal: -3.0 Av. wind speed: 13.3 MPH Av. corrected wind speed: 13.7 MPH Peak gust registered: 51 MPH S on 7th Prevailing direction: S 14% SUNSHINE Total astronomical minutes of bright sunshine: 14392/24094 or 60% Total Campbell-Stokes sun card minutes: 13876/23250 or 60% Today's observations: 7 A.M. Weather: Clear, perfectly clear, SKC Temperature: 54F; Dew Point: 42F; Wind: SW at 4 kts Wind: Light Sea-level pressure: 30.45 ins. Hg, rising slightly Visibility: 60 miles, except NW 70 miles thin smoke layer along horizon distant SSW and NNE, distant haze 6-hour min. temp: 48F BHO SA 1155 CLR 60 311/54/42/2204/045/ SKC VSBY NW 70 THN K LYR ALG HRZN DSNT SSW AND NNE DSNT HZ/ 53006 10054 20048 10 A.M. Weather: Clear, perfectly cleear, SKC Temperature: 68F; Dew Point: 39F; Wind: NW at 3 kts, Wind: Light Sea-level pressure: 30.43 ins. Hg, falling slightly Visibility: 50 miles, except 30 miles N, 25 miles NNE-ENE smoke layer along horizon and aloft NNE and along horizon NE-ENE, distant haze all quadrants BHO SA 1455 CLR 50 306/68/39/3103/043/ SKC VSBY N 30 NNE-ENE 25 K LYR ALG HRZN/ALF NNE AND ALG HRZN NE-ENE DSNT HZ ALQDS WND LGT/ 58005 1 P.M. Weather: Scattered altocumulus, altocumulus lenticularis, few altocumulus castellanus NW, few small cumulus distant SW-MW Temperature: 73F; Dew Point: 33F; Wind: E at 8 kts, Wind: Direction variable NNE-ESE Sea-level pressure: 30.39 ins. Hg, falling then more slowly Visibility: 50 miles, except 25 miles, hazy NE-E, distant haze all quadrants 6-hour max. temp: 75F BHO SA 1755 75 SCT 50 292/73/33/0808/039/ FEW SML CU DSNT SW-NW AC/ACSL ALQDS FEW ACC NW VSBY NE-E 25 HAZY DSNT HZ ALQDS WND 03V12/ 8/140 56014 10075 20054 WEATHER SUMMARY FOR WEDNESDAY, MAY 1, 2013 TEMPERATURE (DEGREES F) MAX.....67 NORMAL.....62 MIN.....45 NORMAL.....43 MEAN....56 NORMAL.....53 DEPARTURE FROM 30-YEAR NORMAL....................+3 TOTAL DEPARTURE FOR THE MONTH....................+3 [+3.0 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............9 DEPARTURE..........-4 TOTAL HEATING UNITS FOR THE MONTH.............9 DEPARTURE..........-4 TOTAL HEATING UNITS FOR THE SEASON.........5531 DEPARTURE........-516 TOTAL HEATING UNITS LAST SEASON TO DATE....4734 DIFFERENCE.......+797 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............18 E AT 11:48 A.M. * AERO....................16 E AT 1:20 P.M. * ASOS....................18 E AT 11:48 A.M. DAVIS...................16 ENE AT 11:15 A.M. RMY: 17 THE FASTEST MILE FOR YESTERDAY.............11 ENE AT 2:30 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE..............13 ENE AT 2:30 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............13 E AT 1:21 P.M. AVERAGE WIND SPEED AND DIRECTION..........6.8 E ASOS...................6.9 DAVIS..................6.2 ESE [120 deg] *last of several occurrences PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00 DEPARTURE...........-0.12 ASOS..............0.00 TOTAL PRECIPITATION FOR THE MONTH..........0.00 DEPARTURE...........-0.12 ASOS..............0.00 TOTAL PRECIPITATION FOR THE YEAR..........16.38 DEPARTURE...........-2.29 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 APRIL AND 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 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/+1/0.09/0.0/063/08 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 31 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/-2/0.00/0.0/514/64 21 ESE AERO 15 MPH S RMY N/A 4/16 62/38/50/+3/T/0.0/540/67 44 S AERO 40 MPH S RMY 45 4/17 67/48/58/+11/T/0.0/769/95 29 SSW AERO 25 MPH SSW RMY N/A 4/18 65/43/54/+6/0.00/0.0/503/62 30 S AERO 25 MPH S RMY N/A 4/19 72/50/61/+13/0.07/0.0/195/24 47 SSW AERO 48 MPH SSW RMY 50 4/20 62/39/51/+2/0.48/0.0/147/18 43 SSW AERO 41 MPH SSW RMY N/A 4/21 53/31/42/-7/0.00/0.0/819/100 31 WNW AERO 25 MPH WNW RMY N/A 4/22 49/35/42/-7/0.00/0.0/551/67 32 E AERO 28 MPH E RMY 33 4/23 40/38/39/-11/0.50/0.0/000/00 35 NNE AERO 30 MPH NNE RMY 35 4/24 72/40/56/+6/0.01/0.0/463/56 36 SSW AERO 33 MPH SSW RMY N/A 4/25 64/44/54/+4/0.05/0.0/581/70 38 W AERO 32 MPH W RMY N/A 4/26 58/42/50/-1/0.00/0.0/607/73 28 ENE AERO 22 MPH ENE RMY N/A 4/27 62/42/52/+1/0.00/0.0/802/96 21 S AERO 17 MPH S RMY 22 4/28 69/44/57/+5/0.00/0.0/771/92 25 S AERO 21 MPH S RMY 27 4/29 69/46/58/+6/0.00/0.0/697/83 25 S AERO 30 MPH S RMY 26 4/30 67/47/57/+5/0.00/0.0/717/85 23 ENE AERO 21 MPH ENE RMY 23 5/1 67/45/56/+3/0.00/.../.. 18 E AERO 16 MPH E RMY 17 5/2 morning low temp: 48F; the normal low is now 44F DAILY RECORDS FOR APRIL 2013 None 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 2 HIGH 92F IN 2001 LOW 29F IN 1903 PRECIP 1.36 INCHES IN 2006 SNOWFALL 1.0 INS IN 1888 PEAK GUST 58 MPH S IN 1983 RECORDS FOR MAY 3 HIGH 92F IN 2001 LOW 31F IN 1888 PRECIP 2.25 INS IN 1900 SNOWFALL TRACE IN 1908, 1985 PEAK GUST 71 MPH W IN 2002 TODAY'S REPORT PREPARED BY: Robert Skilling