Saturday, May 2, 2015

BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 2, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

CLOUDY START GIVES WAY TO CLEAR SKIES BUT BELOW NORMAL
TEMPERATURES REMAIN AS 2015 ENTERS THE TOP TEN FOR LATEST
70-DEGREE READING

As of the 1 o’clock observation, we have again reached over 60
degrees but look unlikely to reach 70.  2015 has entered the
top ten once again by tying 1916 and 1919 for the tenth latest first
70 degree temperature reading. We anticipate that 2015 will move
higher on the chart another day or two.  This is the latest first
70-degree reading since 1975.

Overcast skies have given way to generally clear conditions but a
persistent ocean fog has remained over the outer harbor.  Inland,
quiet conditions exist with very light winds and sunny skies for
the remainder of the day.

BHO Latest First 70-deg Temperature, (1885-2015)

1) 20 May, 1966
2) 19 May, 1917
3) 14 May, 1924
4) 11 May, 1975
5) 10 May, 1893
6) 7 May, 1971
7) 5 May, 1939
8) 3 May, 1937
3 May, 1904
10) 2 May, 1916
2 May, 1919
2 May, 2015

PRELIMINARY STATS FOR APRIL 2015

TEMPERATURE, Deg. F
Avg. Max. 55.9 [+0.2] Avg. Min. 38.4 [+0.7] Mean      47.2 [+0.5] Corrected mean: 46.7
Max. for month: 69 on 4/13
Min. for month: 26 on 4/1

HEATING DEGREE DAYS
Total heating units: 528 [-23] Total for the season: 6271 [+236] Total for last season: 6171

PRECIPITATION, Inches
Total: 3.33 [-1.22] Greatest in 24 hrs: N/A

SNOWFALL, Inches
Total: Trace [-3.0] Greatest in 24 hrs: Trace on 4/8

WIND, mph
Avg. uncorrected wind speed: 12.6
Avg. corrected wind speed: 13.0
Prevailing wind direction: NW @ 16%
Peak gust and direction: 54 NW on the 4th

SUNSHINE:
Astronomical total minutes:   12386 / 24083 or 51%
Campbell-Stokes card minutes: 11946 / 23250 or 51%

Today’s Observations:

7 A.M.
Weather: Overcast stratus with breaks, few stratocumulus all
quadrants
Temperature: 39F; Dew Point: 38F; Wind: NNE at an estimated 6 kts,
Wind: Light
Sea-level pressure: 30.02 ins. Hg, steady then increasing
Visibility: 9 miles, except 6 mi E, 15 mi NW, 25 mi S
6-hr Max temp: 39F
6-hr Min temp: 35F
24-hr precip: 0.00
BHO SA 1155 E5 OVC 9 169/39/38/E5003/002/ FEW SC BINOVC ALQDS
VSBY E 6 S 25 NW 15 HAZY SUN DMLY VSBL WND LGT/ 8/6// 53008
10039 20035

10 A.M.
Weather: Clear, few stratus distant ENE-ESE, few cumulus distant
E-S, few cirrus W-NW
Temperature: 52F; Dew Point: 38F; Wind: NNE at 5 kts,
Wind: Light
Sea-level pressure: 30.02 ins. Hg, steady
Visibility: 50 miles, except 10 ENE-ESE
BHO SA 1455 CLR 50 167/52/38/2005/002/ FEW CU W-NW, SE-S
FEW CI E-S FEW ST ENE-ESE VSBY 10 ENE-ESE HAZY WND LGT/ 8/605 55002

1 P.M.
Weather: Clear, few stratus NE-ESE, few cumulus S-NW, few cirrus
NWN and SE
Temperature: 61F; Dew Point: 37F; Wind: ENE at 6 kts,
Wind Light
Sea-level pressure: 30.00 ins. Hg, steady then falling
Visibility: 70 miles, except 50 mi NE-ESE light distant haze
6-hr Max temp: 61F
6-hr Min temp: 39F
BHO SA 1755 CLR 70 159/61/37/7006/000/ FEW CU S-NW FEW S NE-ESE
FEW CI WNW AND SE VSBY 50 NE-ESE HAZY WND LGT/ 8/562 58009 10061
20039

SUMMARY FOR FRIDAY, MAY 1, 2015

TEMPERATURE (DEGREES F)
MAX…..52   NORMAL…..62
MIN…..37   NORMAL…..43
MEAN….45   NORMAL…..53

DEPARTURE FROM 30-YEAR NORMAL…………………..-8
TOTAL DEPARTURE FOR THE MONTH…………………..-8 [-8.2 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..20  DEPARTURE………..+7
TOTAL HEATING UNITS FOR THE MONTH…………..20  DEPARTURE………..+7
TOTAL HEATING UNITS FOR THE SEASON………..6291  DEPARTURE………+244
TOTAL HEATING UNITS LAST SEASON TO DATE……6182  DIFFERENCE……..+109

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………21 NE    AT   3:47 P.M. *
ASOS…………………..20 ENE   AT   3:46 P.M.
DAVIS………………….19 NE    AT   3:46 P.M. RMY 20
FASTEST MILE FOR YESTERDAY………………..12 NE    AT   3:53 P.M. *
MAXIMUM 2-MINUTE ASOS AVERAGE……………..14 E     AT   4:08 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….14 E     AT   8:36 A.M.
AVERAGE WIND SPEED AND DIRECTION………….7.4 NE
ASOS………………….7.8
DAVIS…………………6.6 NE [059 degrees] * 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………..17.92  DEPARTURE…..-0.62
ASOS…………….N/A ***
*** ASOS annual totals not available due to erroneous readings

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…………..150.8  DEPARTURE….+88.1

PRELIMINARY CLIMATE SUMMARY FOR APRIL CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY GUST
RMY:  R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized

4/1  44/26/35/-6/0.00/0.0/748/98              30 WNW RMY 31
4/2  59/29/44/+3/T/0.0/375/49                 39 SSW RMY 43
4/3  56/47/52/+10/0.02/0.0/000/00             36 SW  RMY N/A
4/4  49/32/41/-1/…./0.0/501/65              54 NW  RMY 64
4/5  47/30/39/-4/…./0.0/464/60              40 W   RMY 45
4/6  48/33/41/-2/0/00/0.0/544/70              18 NE  RMY N/A
4/7  39/34/37/-6/…./0.0/000/00              21 NE  RMY N/A
4/8  41/32/37/-7/…./T/000/00                30 ENE RMY 32
4/9  35/32/34/-10/…./0.0/000/00             31 ENE RMY 32
4/10 53/35/44/-1/…./0.0/000/00              31 SW  RMY N/A
4/11 56/38/46/+1/0.00/0.0/744/94              39 WNW RMY 48
4/12 68/35/52/+7/0.00/0.0/762/96              23 WNW RMY 23
4/13 69/47/58/+12/0.00/0.0/764/96             35 SSW RMY N/A
4/14 65/51/58/+12/0.05/0.0/072/09             37 SSW RMY N/A
4/15 67/45/56/+9/0.00/0.0/786/98              32 NW  RMY 33
4/16 64/42/53/+6/0.00/0.0/765/95              31 S   RMY 21
4/17 64/45/55/+8/0.05/0.0/065/08              31 SSW RMY 32
4/18 64/43/54/+6/0.00/0.0/770/95              31 N   RMY 36
4/19 55/39/47/-1/0.00/0.0/724/89              25 NNW RMY N/A
4/20 55/38/47/-2/…./0.0/000/00              36 SE  RMY 40
4/21 67/51/59/+10/…./0.0/417/51             30 SSE RMY N/A
4/22 67/45/56/+7/0.03/0.0/632/77              44 SSW RMY 52
4/23 49/34/42/-8/0.00/0/0/362/44              32 W   RMY N/A
4/24 50/32/41/-9/0.00/0.0/562/68              32 NW  RMY 36
4/25 56/30/43/-7/0.00/0.0/638/77              26 NW  RMY 29
4/26 54/39/47/-4/0.00/0.0/258/31              17 NW  RMY N/A
4/27 56/42/49/-2/…./0.0/125/15              30 NW  RMY N/A
4/28 63/39/51/-1/…./0.0/527/63              32 NW  RMY 35
4/29 58/46/52/+0/T/0.0/461/55                 24 ENE RMY 22
4/30 60/42/51/-1/0.00/0.0/320/38              21 NE  RMY N/A

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/RMY GUST
RMY:  R.M. Young wind gust recording system
TSTM: Thunderstorm day (thunder heard some time during day)
….: Data not yet available, records not finalized

5/1 52/37/45/-8/0.00/0.0/…/..               21 NE RMY 20

5/2  low since midnight is 35

DAILY RECORDS FOR MAY 2015

NONE

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 Millette/Mike Iacono