BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, MAY 26, 2013 
ALL TIMES ARE IN EASTERN STANDARD TIME
 
MORNING LOW OF 37F TIES DAILY RECORD LOW TEMPERATURE
UNSETTLED STRETCH OF WEATHER COMING TO AN END
 
The morning low temperature fell to 37F at the summit today, tying the record
low for this date which was set in 1972.  This is the first time a low temperature
record has been set or tied since October 13 of last year.  Temperatures have
recovered some today, but the high temperature so far of 56F remains well below the
average of 69F.  Yesterday's average temperature was just 44F, which was 16 degrees
below normal for that date.  The month continues to run a bit above average,
however, by a little more than one degree.  Today has been characterized by mostly
cloudy skies and breezy conditions, with the wind gusting over 30mph at times.
Visibility has been fairly good, as it has generally been between 55 and 65 miles.
 
An additional 0.33 inches of rain fell between 7AM yesterday morning and 7AM
this morning.  A light rain shower between about 8:25 and 9:10 this morning left
just 0.01 inches.  The unsettled weather conditions of the past week have now left
a total of 1.58 inches of rain, which is a considerably lower total than some other
locations across the region.  Still, it has helped to decrease our year to date
precipitation deficit below three inches, and our monthly deficit to under an inch.
Drier and warmer conditions are forecast for most of this week, signaling an end
to this unsettled pattern.
 
Today's observations:
 
7 A.M.
Weather: Overcast stratocumulus, few stratus fractus all quadrants, altocumulus
and altocumulus lenticularis WSW-NW, breaks in overcast S-SW, Sun occasionally
dimly visible
Temperature: 42F; Dew Point: 39F; Wind: WNW at 14G23 kts
Sea-level pressure: 29.78 ins. Hg, rising
Visibility: 65 miles, except 45 miles N-NE
6-hr min. temp: 37F
24-hr precip: 0.33 inch
BHO SA 1155 E35 OVC 65 086/42/39/2914G23/978/ FEW STFRA ALQDS AC/ACSL WSW-NW
BINOVC S-SW SUN OCNL DMLY VSBL VSBY 45 N-NE/ 52017 ASOS 60002
MANUAL 70033 ASOS 70033 8/540 10042 20037
 
10 A.M.
Weather: Overcast stratocumulus, few small cumulus and cumulus fractus, few
altocumulus and altocumulus lenticularis distant NNE-ENE, break in overcast NW
and N
Temperature: 48F; Dew Point: 40F; Wind: WNW at 13G20 kts
Sea-level pressure: 29.84 ins. Hg, rising then rising more slowly 
Visibility: 55 miles, light distant haze
3-hourly precip: 0.01 inch
BHO SA 1455 E35 OVC 55 104/48/40/2913G20/984/ FEW SML CU/CUFRA FEW AC/ACSL DSNT
NNE-ENE BINOVC NW AND N LGT DSNT HZ/ 8/540 51018 MANUAL 6001 ASOS 60000
 
1 P.M.
Weather: Broken stratocumulus, few cumulus W-NW, few altocumulus
Temperature: 55F; Dew Point: 39F; Wind: WNW at 17G28 kts,
Wind: Direction variable WSW-N
Sea-level pressure: 29.88 ins. Hg, rising then rising more slowly
Visibility: 55 miles, except 45 miles N-NE, light distant haze
6-hour max temp: 56F
6-hour precip: 0.01 in. 
BHO SA 1755 E45 BKN 55 117/55/39/3017G28/988/ FEW CU W-NW FEW AC LGT DSNT HZ
WND 25V35 VSBY 45 N-NE/ 8/530 51013 MANUAL 6001 ASOS 60000 10056 20042
 
WEATHER SUMMARY FOR SATURDAY, MAY 25, 2013
 
TEMPERATURE (DEGREES F)
MAX.....50     NORMAL.....69
MIN.....39     NORMAL.....51
MEAN....44     NORMAL.....60
 
DEPARTURE FROM 30-YEAR NORMAL...................-16
TOTAL DEPARTURE FOR THE MONTH...................+37 [+1.3 DEGREES/DAY]
 
HEATING DEGREE DAYS 
TOTAL HEATING UNITS FOR YESTERDAY............21   DEPARTURE.........+15
TOTAL HEATING UNITS FOR THE MONTH...........187   DEPARTURE.........-47
TOTAL HEATING UNITS FOR THE SEASON.........5709   DEPARTURE........-559
TOTAL HEATING UNITS LAST SEASON TO DATE....4888   DIFFERENCE.......+821
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY...............32 NW  AT  4:39 P.M.  
                   AERO....................35 NW  AT  4:51 P.M. 
                   ASOS....................33 NW  AT  4:40 P.M. 
                   DAVIS...................30 WNW AT  4:40 P.M. RMY: 32
FASTEST MILE FOR YESTERDAY.................24 NW  AT  4:40 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..............23 NW  AT  4:41 P.M. 
MAXIMUM 2-MINUTE DAVIS AVERAGE.............23 NW  AT  4:41 P.M. 
AVERAGE WIND SPEED AND DIRECTION.......... 13.1 NW
                   ASOS....................12.6
                   DAVIS...................11.0 NW [323 deg]
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.33  DEPARTURE...........+0.17
                         ASOS..............0.33
TOTAL PRECIPITATION FOR THE MONTH..........2.53  DEPARTURE...........-0.68
TOTAL ASOS PRECIPITATION FOR MONTH.........2.46
TOTAL PRECIPITATION FOR THE YEAR..........18.91  DEPARTURE...........-2.85
                         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 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
                             
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/-3/0.04/.../..         27 WNW AERO 25 MPH WNW RMY N/A
5/23 74/53/64/+5/..../.../..         35 S   AERO 39 MPH S   RMY 40
5/24 68/49/58/-1/..../.../..         33 S   AERO 35 MPH S   RMY N/A
5/25 50/39/44/-16/..../.../..        32 NE  AERO 35 MPH NW  RMY 32
 
5/26 morning low temp: 37F; the normal low is now 51F
 
DAILY RECORDS FOR MAY 2013
5/26- TIED DAILY RECORD MINIMUM TEMPERATURE OF 37F;
ties the record of 37F in 1972.
 
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MAY 26
HIGH 94F IN 2010  (RECORD FOR MAY)
LOW 37F IN 1972, 2013
PRECIP 1.73 INS IN 2003
SNOWFALL TRACE IN 1967 (Fell as ice pellets in nor'easter)
PEAK GUST 62 MPH NE IN 1967
 
RECORDS FOR MAY 27
HIGH 92F IN 1914
LOW 36F IN 1915
PRECIP 1.40 INS IN 1898
PEAK GUST 55 S IN 1956
 
TODAY'S REPORT PREPARED BY: Jonathan O'Brien