BLUE HILL METEOROLOGICAL OBSERVATORY MILTON, MASSACHUSETTS ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA DAILY DISCUSSION AND CLIMATE SUMMARY TUESDAY, JUNE 4, 2013 ALL TIMES ARE IN EASTERN STANDARD TIME COOLER AND MUCH DRIER A cold front swept through the region late last night, ushering in a much cooler and drier air mass for today. The day started off with a crisp morning low of 48F, and the afternoon high temperature is struggling to reach 70F. The average daily temperature for the day is running a few degrees below the 30-year normal. Dew point temperatures have been hanging in the low to mid 40s, making the air mass much drier and more comfortable compared to yesterday's muggy mid 60 degree dew points. A few preliminary spring statistics have been included below the May statistics. It was a slightly warm, dry but very snowy spring. MAY 2013 PRELIMINARY STATISTICS: (departures relative to 1981-2010 average) TEMPERATURE: Average Max Temp: 69.5F [+3.2F] Average Min Temp: 48.2F [+0.4F] Mean Temp: 58.9F [+1.8F] 24-hr. Corr. Mean Temp: 58.2F [+2.0F] Max Temp: 92F on 31st Min Temp: 37F on 5th and 26th Total heating degree day units (month): 212 [ -56] *NCDC method Total heating degree day units (season): 5,734 [-569] *start July 1 (NCDC) PRECIPITATION: Total precipitation: 3.71 inches [-0.40 inches] Greatest 24-hr precipitation: 1.17 on 29th Total snowfall: 0.0 [-0.0 inches] Total seasonal snowfall: 99.0 inches [+36.3 inches] WIND: Avg wind speed: 10.9 MPH Avg corrected wind speed: 11.3 MPH Prevailing wind direction: S [18%] Peak gust: 44 MPH NW on 26th Peak fastest mile: 33 MPH SSW on 11th SUNSHINE: Astronomical minutes: 15,304 of a possible 27,136, or 57% Campbell-Stokes card minutes: 14,850 of a possible 26,226, or 57% Long term average: 52% METEOROLOGICAL SPRING PRELIMINARY STATISTICS (March 1 - May 31): (departures relative to 1981-2010 average) TEMPERATURE: 24-hr. Corr. Mean Temp: 46.8F [+0.7F] PRECIPITATION Total precipitation: 11.70 inches [-2.54 inches] Total snowfall: 37.8 inches [+22.1 inches] *8th snowiest Spring (records 1885-2013) Today's observations: 7 A.M. Weather: Clear, few cirrus distant ENE-S, thin smoke/haze layer aloft distant SSE-SSw and distant WSW-N, light distant haze Temperature: 55F; Dew Point: 42F; Wind: WNW at 10 kts, Wind: Direction variable W-NNW Sea-level pressure: 29.91 ins. Hg, rising Visibility: 70 miles, light distant haze 24-hr precip: 0.43 inch 6-hr min. temp: 48F BHO SA 1155 CLR 70 130/55/42/3010/991/ FEW CI DSNT ENE-S THN K/HZ LYR ALF DSNT SSE-SSW AND DSNT WSW-N LGT DSNT HZ WND 27V34/ 8/001 53014 MANUAL 70043 ASOS 70044 10056 20048 10 A.M. Weather: Scattered cumulus, scattered cirrus, small cumulus forming WSW-NNE, few cirrus distant E-ESE, thin smoke layer aloft distant all quadrants, light distant haze Temperature: 64F; Dew Point: 45F; Wind: WNW at 8 kts, Wind: Direction variable W-NW Sea-level pressure: 29.93 ins. Hg, rising Visibility: 70 miles, light distant haze BHO SA 1455 50 SCT 250 SCT 70 134/64/45/2908/993/ SML CU FRMG WSW-NNE FEW CI DSNT E-ESE THN K LYR ALF DSNT ALQDS LGT DSNT HZ WND 26V32/ 8/101 53004 1 P.M. Weather: Scattered cumulus, broken stratocumulus cumulogenitus, cumulus and stratocumulus all quadrants, mostly clear sky distant ENE-SSW, light distant haze Temperature: 66F; Dew Point: 44F; Wind: WNW at 11G19 kts, Wind: Direction variable W-NNW Sea-level pressure: 29.95 ins. Hg, rising Visibility: 70 miles, light distant haze 6-hour max temp: 68F BHO SA 1755 55 SCT E60 BKN 70 141/66/44/3011G19/995/ CU/SC ALQDS MSTLY CLR SKY DSNT ENE-SSW LGT DSNT HZ WND 27V33/ 8/400 52007 10068 20055 WEATHER SUMMARY FOR MONDAY, JUNE 3, 2013 TEMPERATURE (DEGREES F) MAX.....75 NORMAL.....71 MIN.....57 NORMAL.....53 MEAN....66 NORMAL.....62 DEPARTURE FROM 30-YEAR NORMAL....................+4 TOTAL DEPARTURE FOR THE MONTH...................+35 [+11.5 DEGREES/DAY] HEATING DEGREE DAYS TOTAL HEATING UNITS FOR YESTERDAY.............0 DEPARTURE..........-4 TOTAL HEATING UNITS FOR THE MONTH.............0 DEPARTURE.........-14 TOTAL HEATING UNITS FOR THE SEASON.........5734 DEPARTURE........-583 TOTAL HEATING UNITS LAST SEASON TO DATE....4909 DIFFERENCE.......+825 PEAK GUST AND AVERAGE WIND SPEED (MPH) PEAK WIND GUST FOR YESTERDAY...............22 WNW AT 11:19 P.M. AERO....................22 SSW AT 4:54 A.M. ASOS....................22 WNW AT 11:20 P.M. DAVIS...................22 WNW AT 11:20 P.M. RMY: 22 FASTEST MILE FOR YESTERDAY.................15 WNW AT 11:18 P.M. * MAXIMUM 2-MINUTE ASOS AVERAGE..............15 WNW AT 11:21 P.M. MAXIMUM 2-MINUTE DAVIS AVERAGE.............16 S AT 3:38 A.M. AVERAGE WIND SPEED AND DIRECTION..........8.7 S ASOS...................8.4 DAVIS..................8.1 SSW [214 deg] *last of several occurrences... PRECIPITATION (INCHES) THROUGH THIS MORNING (EST) TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.43 DEPARTURE...........+0.27 ASOS..............0.44 TOTAL PRECIPITATION FOR THE MONTH..........0.47 DEPARTURE...........-0.02 ASOS..............0.47 TOTAL PRECIPITATION FOR THE YEAR..........20.56 DEPARTURE...........-2.59 ASOS..............N/A* *ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals PRELIMINARY CLIMATE SUMMARY FOR MAY & JUNE 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/-1/0.00/600/70 17 S AERO 18 MPH S RMY 20 5/7 77/50/64/+9/0.00/807/94 21 S AERO 23 MPH S RMY 25 5/8 71/55/63/+8/0.42/112/13 31 SSE AERO 35 MPH SSE RMY 35 TSTM 5/9 66/56/61/+6/0.41/078/09 16 NE AERO 16 MPH NE RMY 18 TSTM 5/10 79/54/67/+12/T/333/63 18 S AERO 21 MPH S RMY N/A 5/11 70/56/63/+7/0.06/026/03 43 SSW AERO 44 MPH SSW RMY 46 5/12 71/47/59/+3/0.05/339/39 30 W AERO 32 MPH W RMY 32 5/13 60/41/51/-5/0.00/821/94 25 WSW AERO 28 MPH WSW RMY 30 5/14 58/38/48/-9/T/385/44 22 W AERO 24 MPH W RMY 25 5/15 65/41/53/-4/0.02/456/52 35 S AERO 38 MPH S RMY 40 5/16 80/51/66/+9/0.00/844/96 40 W AERO 45 MPH W RMY 42 5/17 69/50/60/+3/0.00/872/99 24 NW AERO 28 MPH NW RMY 27 5/18 73/47/60/+2/0.00/689/78 21 SE AERO 24 MPH SE RMY 24 5/19 71/50/61/+3/0.11/407/46 21 S AERO 23 MPH S RMY 24 5/20 81/54/68/+10/0.01/496/56 21 S AERO 21 MPH S RMY N/A 5/21 81/49/65/+6/0.14/506/57 29 NE AERO 31 MPH NE RMY 32 TSTM 5/22 66/48/57/-2/0.04/009/01 27 WNW AERO 25 MPH WNW RMY N/A 5/23 74/53/64/+5/0.09/036/04 35 S AERO 39 MPH S RMY 40 5/24 68/49/59/0/0.57/000/00 33 S AERO 35 MPH S RMY N/A 5/25 50/39/45/-15/0.59/000/00 32 NW AERO 35 MPH NW RMY 32 5/26 58/37/48/-12/0.03/332/37 44 NW AERO 44 MPH NW RMY 45 5/27 70/41/56/-4/0.00/880/98 33 WNW AERO 33 MPH WNW RMY 36 5/28 74/55/65/+4/0.00/639/71 20 S AERO 20 MPH S RMY 21 5/29 71/56/64/+3/1.17/045/05 25 W AERO 27 MPH W RMY 27 TSTM 5/30 86/63/75/+14/0.00/839/93 25 W AERO 25 MPH W RMY 27 5/31 92/68/80/+19/0.00/805/89 25 SW AERO 25 MPH SW RMY 27 6/1 90/69/80/+18/0.00/.../.. 30 SW AERO 32 MPH SW RMY 33 6/2 86/64/75/+13/0.00/.../.. 42 SSW AERO 44 MPH SSW RMY 46 6/3 75/57/66/+4/0.47/.../.. 22 WNW AERO 22 MPH SSW RMY 22 6/4 morning low temp: 48F; the normal low is now 54F DAILY RECORDS FOR MAY 2013 5/26 - TIED DAILY RECORD MINIMUM TEMPERATURE OF 37F; previous record of 37F set in 1972. 5/31 - TIED DAILY RECORD MAXIMUM TEMPERATURE OF 92F; previous record of 92F set in 1937. DAILY RECORDS FOR JUNE 2013 6/1 - TIED DAILY RECORD MAXIMUM TEMPERATURE OF 90F; previous record of 90F set in 1937 6/1 - NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 69F; surpasses previous record of 68F set in 1944, 1987 DAILY EXTREMES Temperature and precipitation records back to 1885, and wind records back to 1940 (e = estimated): RECORDS FOR JUNE 4 HIGH 99F IN 1919 [Record for month] LOW 41F IN 1915,1926 PRECIP 1.52 INS IN 2007 PEAK GUST 48 MPH SSE IN 1983 RECORDS FOR JUNE 5 HIGH 95F IN 1930 LOW 41F IN 1891 PRECIP 2.83 INS IN 1982 PEAK GUST 57 MPH NNW IN 1988 TODAY'S REPORT PREPARED BY: Sean Fankhauser