BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, MAY 30, 2012
ALL TIMES ARE IN EASTERN STANDARD TIME
 
VERY BRIEF DOWNPOUR AND A FEW RUMBLES OF THUNDER
LATE LAST EVENING
 
A five-minute downpour brought 0.11 inch in just
5 minutes around 10:15 P.M. last evening. A few
rumbles of thunder was all that was left of the
severe thunderstorms in western Massachusetts, New
York State, Vermont and New Hampshire yesterday
afternoon and evening. 
 
A SNAPSHOT OF MAY 2012 - THROUGH 29 DAYS....
11TH CONSECUTIVE WARMER THAN NORMAL MONTH 
19 DAYS WITH FOG, 15 OF THEM HEAVY FOG
VERY LOW AVERAGE WIND SPEED UNDER 10 MPH (UNCORRECTED)
SUNSHINE AROUND 40% IS WELL BELOW AVERAGE
PRECIPITATION NEAR 90% OF NORMAL, YEAR 58% OF NORMAL
 
May has been yet another month (making it 11 consecutive)
to average above normal in temperature. Many days with
fog and with only around 40% of the normal average sun-
shine it has been somewhat a gloomy month.  However with
three consecutive sunny weekends the gloomy weather
has been mostly on weekdays.
The average uncorrected wind speed for the month is unusually
low at 9.5 MPH for 29 days and so we will likely end up 
close to if not the calmest May on record. 
Sunshine at around 40% of possible is 12 points under the long-term
average of 52%.
Precipitation has totaled near 90% of the norm so fairly close
to the average.
 
Today's observations:
 
7 A.M.
Weather: Scattered altocumulus, overcast altocumulus of a chaotic
sky, bright spots, higher clouds (dense cirrus) visible overhead
thru northeast thru east-southeast
Temperature: 66F, Dew Point: 64F; Wind: W at 7 kts,
Sea-level pressure: 29.75 inches Hg, rising then more slowly
Visibility: 15 miles, light rain shower, very light, thin fog
and also hazy
6-hour min. temp: 62F
24-hour precip: 0.11 inch 
BHO SA 1155 85 SCT E100 OVC 15RW- 075/66/64/2607/975/ AC CHAOTIC ALQDS 
HIER CLD BRGHT SPTS DNS CI VSB OVHD-NE-ESE VSBY N 12 ENE AND WNW 20
THN F/HZY ALQDS RB55/ 8/092 51011 MANUAL 6000/ MANUAL 70011 ASOS 70011
10066 20062
 
10 A.M.
Weather: Broken altocumulus, overcast altocumulus of a chaotic sky,
few altocumulus castellanus ESE
Temperature: 70F, Dew Point: 63F; Wind: NW at 4 kts,
Sea-level pressure: 29.76 inches Hg, rising then more slowly
Visibility: 25 miles, N-E 20 miles 
3-hour precip: trace
BHO SA 1455 E80 BKN 95 OVC 25 079/70/63/3104/976/ FEW ACC ESE
VSBY N-E 20 HAZY ALQDS/ 8/09/ 51004 MANUAL 6000/ 
 
1 P.M.
Weather: Scattered altocumulus of chaotic sky, bright high overcast
of dense cirrus
Temperature: 72F, Dew Point: 61F; Wind: W at 3 kts,
Wind: Light
Sea-level pressure: 29.76 inches Hg, falling slightly
Visibility: 35 miles, except 25 miles NE-SE, WNW 40 miles distant haze
6-hour max. temp: 72F  
6-hour precip: trace 
BHO SA 1755 95 SCT E180 OVC 35 078/72/61/2603/976/ SCT AC
CHAOTIC 180 BRGHT OVC DNS CI VSBY NE-SE 25 WNW 40 DSNT HZ
WND LGT/ 8/092 58001 MANUAL 6000/ 10072 20066
 
WEATHER SUMMARY FOR TUESDAY, MAY 29
 
TEMPERATURE (DEGREES F)
MAX.....78    NORMAL.....70
MIN.....59    NORMAL.....52
MEAN....69    NORMAL.....61
 
DEPARTURE FROM 30-YEAR NORMAL........................+8
TOTAL DEPARTURE FOR THE MONTH.......................+90 [+2.9 DEGREES/DAY]
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY...............0   DEPARTURE..........-5
TOTAL HEATING UNITS FOR THE MONTH.............174   DEPARTURE.........-87
TOTAL HEATING UNITS FOR THE SEASON...........4888   DEPARTURE.......-1399
TOTAL HEATING UNITS LAST SEASON TO DATE......6153   DIFFERENCE......-1265
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............24 N   AT  7:43 P.M.
                   AERO..................24 N   AT  7:43 P.M.
                   ASOS..................24 N   AT  7:43 P.M.
                   DAVIS.................24 N   AT  7:42 P.M. RMY 25
THE FASTEST MILE FOR YESTERDAY.......... 18 N   AT  7:43 P.M. 
MAXIMUM 2-MINUTE ASOS AVERAGE............18 N   AT  7:44 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE...........18 N   AT  7:44 P.M.
AVERAGE WIND SPEED AND DIRECTION........6.9 S
                   ASOS.................6.7
                   DAVIS................6.8 SE [140 deg.]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.11   DEPARTURE..........-0.03
                         ASOS..............0.11
TOTAL PRECIPITATION FOR THE MONTH..........3.63   DEPARTURE..........-0.17
                         ASOS..............3.52
TOTAL PRECIPITATION FOR THE YEAR..........13.24   DEPARTURE..........-9.11
                         ASOS.............13.25
     
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..........-0.1
TOTAL SNOWFALL FOR THE SEASON..............24.2    DEPARTURE.........-35.9
 
PRELIMINARY CLIMATE SUMMARY FOR MAY 2012 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust when significant
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  47/42/45/-8/0.65/0.0/000/00    33 SE  AERO 36 MPH SE  RMY 37
5/2  50/43/47/-6/0.05/0.0/000/00    16 ENE AERO 16 MPH ENE RMY 17
5/3  51/44/48/-5/0.08/0.0/000/00    14 SSE AERO 16 MPH SSE RMY N/A
5/4  56/47/52/-2/0.01/0.0/000/00    21 SSW AERO 25 MPH SSW RMY 23
5/5  57/46/52/-2/0.04/0.0/034/04    14 NE  AERO 15 MPH NE  RMY 15
5/6  58/45/52/-2/0.00/0.0/532/62    21 ENE AERO 21 MPH ENE RMY 21
5/7  67/48/58/+3/0.00/0.0/740/86    23 S   AERO 25 MPH S   RMY 25
5/8  57/48/53/-2/0.18/0.0/000/00    40 S   AERO 46 MPH S   RMY 46
5/9  61/54/58/+3/0.36/0.0/000/00    25 S   AERO 28 MPH S   RMY N/A
5/10 65/46/56/+1/0.98/0.0/234/27    33 W   AERO 36 MPH W   RMY 37
5/11 62/42/52/-4/T/0.0/539/62       30 WNW AERO 33 MPH WNW RMY 34
5/12 77/46/62/+6/0.00/0.0/862/99    30 W   AERO 30 MPH W   RMY 29
5/13 82/57/70/+14/0.00/0.0/314/36   27 S   AERO 29 MPH S   RMY 29
5/14 71/52/62/+5/0.05/0.0/096/11    23 S   AERO 24 MPH S   RMY 23
5/15 72/57/65/+8/0.43/0.0/123/14    32 S   AERO 35 MPH S   RMY 33
5/16 71/58/65/+8/0.12/0.0/141/16    23 S   AERO 24 MPH S   RMY N/A TSTM
5/17 69/50/60/+3/0.00/0.0/784/89    31 WNW AERO 32 MPH WNW RMY 26
5/18 69/49/59/+1/0.00/0.0/857/97    17 ESE AERO 17 MPH ESE RMY 17
5/19 74/51/63/+5/0.00/0.0/876/99    15 WNW AERO 15 MPH WNW RMY 16
5/20 79/56/68/+10/0.00/0.0/727/82   17 SE  AERO 17 MPH SE  RMY 17
5/21 64/52/58/-1/0.02/0.0/009/01    17 NE  AERO 16 MPH NNE RMY 18
5/22 61/56/59/0/0.54/0.0/000/00     23 NE  AERO 23 MPH NE  RMY 23 
5/23 75/57/66/+7/0.00/0.0/366/41    15 S   AERO 16 MPH S   RMY 15
5/24 75/59/67/+8/0.00/0.0/751/84    20 SSE AERO 21 MPH SE  RMY 21
5/25 73/57/65/+5/0/01/0.0/054/06    26 S   AERO 25 MPS S   RMY 25
5/26 84/63/74/+14/0.00/0.0/350/39   24 SSW AERO 24 MPH SW  RMY 23
5/27 75/62/69/+9/0.00/0.0/817/91    27 NNE AERO 24 MPH S   RMY 24
5/28 72/58/65/+4/0.00/0.0/585/65    22 S   AERO 21 MPH S   RMY 20
5/29 78/59/69/+8/0.11/0.0/360/40    24 N   AERO 24 MPH N   RMY 25  TSTM 
 
5/30 morning low temp: 62F; the normal low is now 52F
 
DAILY RECORDS FOR MAY 2012
5/16 - TIED DAILY RECORD HIGH MINIMUM TEMP OF 58F;
ties the record of 58F in 1951 and 1961.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MAY 30
HIGH 93F IN 1929
LOW 39F IN 1949,1961
PRECIP 1.47 INS 1948
PEAK GUST 61e MPH NW IN 1945
 
RECORDS FOR MAY 31
HIGH 92F IN 1944,1987
LOW 35F IN 1961
PRECIP 5.02 INS 1984 (RECORD FOR MAY)
PEAK GUST 54e MPH WNW IN 1945
 
TODAY'S REPORT PREPARED BY: Robert Skilling