BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, MAY 2, 2012
ALL TIMES ARE IN EASTERN STANDARD TIME
 
Low clouds linger today with overcast conditions after
an early morning obscurement with dense fog.  In addition,
light drizzle was very persistent since rain ended on
Tuesday mid-late afternoon.  A few hundredths of an inch
of precipitation was recorded in light drizzle early
this morning.  Yesterday's rainfall event brought a
very welcome 0.70 inch including the drizzle early today.
 
Temperatures continue on the cool side of normal for a
6th consecutive day below normal.  The previous run of
below normal daily temperature was four days way back
in January.
 
April 2012 finished as the 3rd warmest on record.  
See additional preliminary April 2012 stats below.
In addition, April was much sunnier than the long-term
average.  The actual sunshine percentage recorded
was 64% of possible; long-term average for 115 years
of records is 49%. 

The year to date through April is the warmest on record, 
and it is the second driest on record. 
 
BHO Warmest April Corrected Mean Temp, 1885-2012 (deg F)
1) 51.5 in 2010
2) 51.0 in 1976
3) 49.9 in 2012
4) 49.4 in 1945
5) 49.0 in 1994
 
BHO Warmest January-April Corrected Mean Temp, 1885-2012 (deg F)
1) 39.7 in 2012
2) 38.3 in 2002
3) 37.9 in 1998
4) 37.2 in 2010
5) 36.9 in 1990
 
BHO Driest January-April, 1885-2012 (inches)
1)  9.19 in 1985
2)  9.61 in 2012
3) 10.41 in 1927
4) 10.74 in 1941
5) 10.89 in 1892

APRIL 2012 PRELIMINARY STATS
 
TEMPERATURE:
Average Max Temp:  61.8F [+6.1F]
Average Min Temp:  40.1F [+2.4F]
Mean Temp:  51.0F [+4.3F]
24-hr. Corr Mean Temp:  49.9F
Max Temp:  89F on 16th
Min Temp:  31F on  3rd, 6th, 28th
Total heating degree day units (month):    429   [-133]
Total heating degree day units (season): 4,714 [-1,312] *start July 1
Total cooling degree day units (month):     11     [+8]
Total cooling degree day units (season):    15    [+11] *start Jan 1
 
PRECIPITATION:
Total precipitation:  3.52 ins. [-1.03 ins.]
Greatest 24-hr precipitation:  3.11 ins. on 22nd-23rd
Total snowfall:  Trace [-3.1 ins.]
 
WIND:
Avg wind speed: 12.8 MPH
Avg corrected wind speed:  13.2 MPH
Prevailing wind direction: NW [18%]
Peak gust:  50 MPH NE on 22nd
Peak fastest mile: 37 MPH NE on 22nd, 23rd
 
SUNSHINE:
Total Campbell-Stokes card minutes: 14982; poss. 23250 or 64%
Total astronomical minutes:         15458; poss. 24094 or 64%
 
Today's observations:
 
7 A.M.
Weather: Obscured with fog, light drizzle occurring along with the
dense fog
Temperature: 44F, Dew point: 44F, Wind: NE at 5 kts,
Sea-level pressure: 30.20 inches Hg, rising then falling slightly
Visibility: 1/4 mile variable 1/8 to 1/2 and increasing,
visibility SW 1 mile, light drizzle and fog
24-hour precip: 0.64 inch
6-hour precip: 0.02 inch
6-hour min. temp: 43F
BHO SA 1155 W3 1/4VL-F 226/44/44/0505/020/ VSBY 1/8V1/2 INCRSG
VSBY SW 1/ 8//// 50008 ASOS 60002 MANUAL 60002 ASOS 70064
MANUAL 70064 10044 20043
 
10 A.M.
Weather: Overcast stratus, ceiling ragged, bright spots in
the overcast 
Temperature: 46F, Dew Point: 45F; Wind: ENE at 5 kts,
Sea-level pressure: 30.24 inches Hg, rising then more slowly
Visibility: 10 miles, NE-E 8 miles, ESE 5 miles, S-SW 25 miles,
thin fog and some drizzle
3-hour precip: trace
BHO SA 1455 E5 OVC 10 239/46/45/0605/024/ CIG RGD
BRGHT SPTS IOVC VSBY NE-E 6 ESE 5 SW 25 THN F ALQDS/
8/6// 51013 MANUAL 6000/
 
1 P.M. 
Weather: Overcast stratocumulus, higher cloud visible
distant NE, bright spots in overcast
Temperature: 49F, Dew Point: 45F; Wind: NE at 7 kts,
Wind: Direction variable NNE-E
Sea-level pressure: 30.22 inches Hg, falling steadily 
Visibility: 50 miles, mountain in cloud 45 WNW 
6-hour precip: trace
6-hour max. temp: 50F
6-hour min. temp: 44F
BHO SA 1755 E15 OVC 50 233/49/45/0507/022/ HIER CLD VSB DSNT NE
BRGHT SPTS IOVC MTN INCLD 45 WNW WND 02V09/ 8/5// 57006 MANUAL 6000/
10050 20044
 
WEATHER SUMMARY FOR TUESDAY, MAY 1
 
TEMPERATURE (DEGREES F)
MAX.....47    NORMAL.....62
MIN.....42    NORMAL.....43
MEAN....45    NORMAL.....53
 
DEPARTURE FROM 30-YEAR NORMAL.......................-8
TOTAL DEPARTURE FOR THE MONTH.......................-8 DEGREES
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..............20   DEPARTURE..........+7
TOTAL HEATING UNITS FOR THE MONTH..............20   DEPARTURE..........+7
TOTAL HEATING UNITS FOR THE SEASON...........4734   DEPARTURE.......-1305
TOTAL HEATING UNITS LAST SEASON TO DATE......5911   DIFFERENCE......-1177
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY.............33 SE  AT 10:30 A.M.
                   AERO..................36 SE  AT 10:30 A.M.
                   ASOS..................33 SE  AT 10:30 A.M.
                   DAVIS.................35 SE  AT 10:29 A.M. RMY 37
THE FASTEST MILE FOR YESTERDAY...........26 SE  AT 10:31 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE............24 SE  AT 10:31 A.M.
DAVIS MAXIMUM 2-MINUTE AVERAGE...........25 SE  AT 10:31 A.M.
AVERAGE WIND SPEED AND DIRECTION.......12.3 NE 
                   ASOS................11.4
                   DAVIS...............11.5 ESE [120 deg.]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.64   DEPARTURE..........+0.52
                         ASOS..............0.64
TOTAL PRECIPITATION FOR MAY................0.70   DEPARTURE..........+0.58
                         ASOS..............0.69
TOTAL PRECIPITATION FOR APRIL..............3.52   DEPARTURE..........-1.03
                         ASOS..............3.58
TOTAL PRECIPITATION FOR THE YEAR..........10.42   DEPARTURE..........-8.36                                    
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0    DEPARTURE..........-0.1
TOTAL SNOWFALL FOR MAY......................0.0    DEPARTURE...........N/A
TOTAL SNOWFALL FOR APRIL....................0.0    DEPARTURE..........-3.1
TOTAL SNOWFALL FOR THE SEASON..............24.2    DEPARTURE.........-35.9
 
PRELIMINARY CLIMATE SUMMARY FOR APRIL & 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
 
4/1  50/34/42/+1/0.14/0.0/360/47    20 SSW AERO 20 MPH SSW RMY N/A
4/2  51/35/43/+2/0.04/T/353/46      35 NNW AERO 33 MPH NNW RMY 35
4/3  57/31/44/+2/0.00/0.0/724/94    36 NW  AERO 37 MPH NW  RMY 40
4/4  62/38/50/+8/T/0.0/688/89       40 NW  AERO 39 MPH NW  RMY 43
4/5  51/33/42/-1/0.00/0.0/660/85    29 NW  AERO 27 MPH NW  RMY 30
4/6  51/31/41/-2/0.00/0.0/623/80    26 NNW AERO 26 MPH NNW RMY 28
4/7  54/32/43/0/0.00/0.0/305/39     31 NW  AERO 32 MPH NW  RMY 32
4/8  51/37/44/0/0.00/0.0/086/11     32 NW  AERO 31 MPH NW  RMY 33
4/9  57/43/50/+6/T/0.0/323/41       44 W   AERO 42 MPH W   RMY 44
4/10 61/40/51/+6/0.00/0.0/600/76    32 W   AERO 31 MPH W   RMY 34
4/11 57/40/49/+4/0.00/0.0/397/50    21 NE  AERO 20 MPH NE  RMY 22
4/12 54/39/47/+2/0.16/0.0/127/16    25 NNW AERO 24 MPH NNW RMY 28
4/13 63/36/50/+4/0.00/0.0/782/98    24 W   AERO 23 MPH W   RMY 25
4/14 70/44/57/+11/0.00/0.0/617/77   25 SSW AERO 27 MPH SSW RMY 28
4/15 75/52/64/+17/T/0.0/426/53      23 W   AERO 23 MPH W   RMY 25
4/16 89/57/73/+26/0.01/0.0/678/84   28 SSW AERO 30 MPH SSW RMY 32
4/17 83/53/68/+21/0.00/0.0/777/96   28 W   AERO 28 MPH W   RMY 32
4/18 61/45/53/+5/0.00/0.0/487/60    27 NNW AERO 27 MPH NNW RMY N/A
4/19 70/44/57/+9/0.00/0.0/676/83    23 S   AERO 22 MPH S   RMY 25
4/20 75/46/61/+12/0.00/0.0/768/94   30 S   AERO 31 MPH S   RMY 33
4/21 75/51/63/+14/T/0.0/508/62      32 S   AERO 37 MPH SSW RMY 38
4/22 59/41/50/+1/1.16/0.0/000/00    50 NE  AERO 51 MPH NE  RMY 52
4/23 61/42/52/+2/1.99/0.0/000/00    46 NE  AERO 47 MPH NE  RMY 48
4/24 57/43/50/0/0.00/0.0/737/89     37 SSW AERO 42 MPH S   MMY N/A
4/25 61/41/51/+1/T/0.0/548/66       32 W   AERO 33 MPH W   RMY 32
4/26 66/36/51/0/0.01/0.0/417/50     29 SSW AERO 31 MPH SSW RMY N/A
4/27 56/36/46/-5/0.01/0.0/568/68    39 W   AERO 41 MPH W   RMY 42
4/28 58/31/45/-7/0.00/0.0/821/98    30 WNW AERO 35 MPH WNW RMY 31
4/29 58/36/47/-5/0.00/0.0/807/96    38 NW  AERO 42 MPH NW  RMY 42
4/30 61/35/48/-4/0.00/0.0/641/76    23 S   AERO 25 MPH S   RMY 26
 
5/1  47/42/45/-8/..../0.0/000/00    33 SE  AERO 36 MPH SE  RMY 37
 
5/2  our morning low temp: 43F; the normal low is now 44F
 
DAILY RECORDS FOR MAY 2012
None so far.
 
DAILY RECORDS FOR APRIL 2012
4/16 - NEW DAILY RECORD HIGH MAXIMUM TEMP OF 89F;
surpasses the previous record of 87F in 1896.
4/23 - NEW DAILY RECORD PRECIPITATION OF 1.99 INCHES;
surpasses the previous record of 1.51 inches in 1998.
 
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