Sunday, May 10, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, MAY 10, 2015 MOTHER’S DAY
ALL TIMES ARE IN EASTERN STANDARD TIME

HUMIDITY ON THE RISE AS TEMPERATURES SOAR TODAY

Temperatures were on the rise overnight from a low
of 60F, some 14 degrees above normal daily minimum.
Dew points followed suit and reached the lowers 60s
by early morning. Following another day of above
average temperatures, the first nine days of May are
now 5.5 degrees above normal.

By the 1:00 PM EST observation hazy and hot conditions
were present, with a maximum reading of 86F. Haze had
limited visibility to just 25 miles in all directions.

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: 1.41 on 4/20-4/21

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: Broken stratocumulus, broken cirrus
Temperature: 67F; Dew Point: 61F; Wind: WSW at 10 kts
Sea-level pressure: 30.20 ins. Hg, rising slightly
Visibility: 25 miles, thin fog in all directions
6-hr Max temp: 67F
6-hr Min temp: 60F
24-hr precip: none
BHO SA 1155 E15 BKN 250 BKN 25 227/67/61/2510/020/
THN FG ALQDS/ 8/501 51002 10067 20060

10 A.M.
Weather: Thin broken cirrus, few small cumulus in all directions,
few altocumulus lenticularis distant WNW-NE
Temperature: 76F; Dew Point: 61F; Wind: SW at 13G18 kts,
Sea-level pressure: 30.16 ins. Hg, falling, then more slowly
Visibility: 30 miles, hazy
BHO SA 1455 E250 -BKN 30 212/76/61/2313G18/016/
FEW SML CU ALQDS FEW ACSL DSNT WNW-NE HAZY/ 8/141 56015

1 P.M.
Weather: Thin scattered cirrus, few small cumulus in all directions
Temperature: 86F; Dew Point: 61F; Wind: WSW at 12G20 kts,
Sea-level pressure: 30.11 ins. Hg, falling, then more quickly
Visibility: 25 miles, hazy
6-Hr Max temp: 86F
6-Hr Min temp: 66F
BHO SA 1755 250 -SCT 25 196/86/61/2512G20/011/
FEW SML CU ALQDS HAZY/ 8/101 58016 10086 20066

SUMMARY FOR SATURDAY, MAY 9, 2015

TEMPERATURE (DEGREES F)
MAX…..77   NORMAL…..64
MIN…..44   NORMAL…..46
MEAN….61   NORMAL…..55

DEPARTURE FROM 30-YEAR NORMAL…………………..+6
TOTAL DEPARTURE FOR THE MONTH………………….+51 [+5.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY……………4  DEPARTURE………..-6
TOTAL HEATING UNITS FOR THE MONTH…………..53  DEPARTURE……….-50
TOTAL HEATING UNITS FOR THE SEASON………..6324  DEPARTURE………+186
TOTAL HEATING UNITS LAST SEASON TO DATE……6255  DIFFERENCE………+69

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..0   DEPARTURE……….+0
TOTAL COOLING UNITS FOR THE MONTH…………..5   DEPARTURE……….+5
TOTAL COOLING UNITS FOR THE SEASON………….5   DEPARTURE……….+5
TOTAL COOLING UNITS LAST SEASON TO DATE……..0   DIFFERENCE………+5

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………30 S     AT   2:18 P.M.
ASOS…………………..32 S     AT   2:18 P.M.
DAVIS………………….31 S     AT   2:18 P.M. RMY 32
FASTEST MILE FOR YESTERDAY………………..23 S     AT   3:41 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..23 S     AT   3:42 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….22 S     AT   3:42 P.M.
AVERAGE WIND SPEED AND DIRECTION………….9.4 S
ASOS………………….9.0
DAVIS…………………8.2 S [188 degrees] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE…..-0.11
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..0.03  DEPARTURE…..-1.07
ASOS……………0.03
TOTAL PRECIPITATION FOR THE YEAR………..17.95  DEPARTURE…..-1.57
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/-1/0.32/0.0/501/65              54 NW  RMY 64  TSTM
4/5  47/30/39/-4/T/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/-6/0.13/0.0/000/00              21 NE  RMY N/A
4/8  41/32/37/-7/0.51/T/000/00                30 ENE RMY 32
4/9  35/32/34/-10/0.38/0.0/000/00             31 ENE RMY 32
4/10 53/35/44/-1/0.07/0.0/000/00              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/+8/0.16/0.0/065/08              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/-2/1.00/0.0/000/00              36 SE  RMY 40
4/21 67/51/59/+10/0.44/0.0/417/51             30 SSE RMY N/A TSTM
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/-2/0.15/0.0/125/15              30 NW  RMY N/A
4/28 63/39/51/-1/0.10/0.0/527/63              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 63/35/49/-4/0.00/0.0/…/..               20 S   RMY 20
5/3 74/44/59/+6/0.00/0.0/…/..               22 S   RMY 22
5/4 83/47/65/+11/0.00/0.0/…/..              39 SSW RMY 45
5/5 77/56/67/+13/0.03/0.0/…/..              29 SW  RMY N/A
5/6 74/54/64/+10/0.00/0.0/…/..              24 SSW RMY 25
5/7 84/52/68/+13/0.00/0.0/…/..              29 S   RMY 32
5/8 74/44/59/+4/0.00/0.0/…/..               27 NNE RMY 26
5/9 77/44/61/+6/0.00/0.0/…/..               30 S   RMY 32

5/10 low since midnight is 60F; normal low now 46F

DAILY RECORDS FOR MAY 2015

NONE SO FAR

DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):

RECORDS FOR MAY 10
HIGH 93F IN 1896
LOW 29F IN 1900
PRE 1.85 INS IN 1998
SNOW 2.8 INS 1977 (7.8 INS TOTAL 5/9-5/10 1977)
PEAK GUST 64 MPH S IN 1990

RECORDS FOR MAY 11
HIGH 90F IN 1993
LOW 28F IN 1900
PRE 1.28 INS IN 1957
SNOW 1.0 INS IN 1907 (LATEST MEASURABLE SNOW ON RECORD)
PEAK GUST 75e MPH NW IN 1945

TODAY’S REPORT PREPARED BY: Brian Fitzgerald