Friday, May 1, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, MAY 1, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

APRIL COOLNESS SPILLS INTO MAY, PATTERN SHIFT
AND WARM UP ON THE WAY

Yesterday’s maximum of 60F came briefly before 3:00 PM EST,
before the mercury tumbled once more overnight. This morning’s
minimum of 40F came along with mostly cloudy conditions and
a continued NE wind. Brief drizzle this morning wrapped up
before the 7:00 AM EST observation, bringing just a trace
of new precipitation.

Cool conditions mean another day without this year’s first
70 degree day. A significant warm up still does not seem
likely this week, possibly inching 2015 closer to the top
10 latest 70 degree readings.

BHO Latest First 70-deg Temperature, (1885-2014)

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
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:   N/A / N/A  or N/A%
Campbell-Stokes card minutes: N/A / N/A  or N/A%

 

Today’s Observations:

7 A.M.
Weather: Overcast stratus, showers distant NNE-NE, drizzle
ends 6:34 AM EST
Temperature: 43F; Dew Point: 39F; Wind: estimated NE at 6 kts,
Wind Speed and Direction: Light and Variable
Sea-level pressure: 30.01 ins. Hg, rising unsteadily
Visibility: 40 miles, except 15 miles NNE-NE, obscured by showers
6-hr Max temp: 43F
6-hr Min temp: 40F
24-hr precip: Trace
BHO SA 1155 E10 OVC 40 164/43/39/E0406/001/ L-E34 VSBY NNE-NE 15 MI
SHWRS DSNT NNE-NE WND LGT AND VRB/ 8/6// 51013 MANUAL 6000/ 10043
20040

10 A.M.
Weather: Broken stratocumulus, few cumulus distant WNW-NNE
Temperature: 47F; Dew Point: 38F; Wind: NE at 8 kts,
Sea-level pressure: 30.02 ins. Hg, increasing, then more quickly
Visibility: 70 miles
BHO SA 1455 E18 BKN 70 166/47/38/0408/002/ FEW CU DSNT WNW-NNE/
8/500 53002

1 P.M.
Weather: Scattered cirrus, few stratocumulus/cumulus ENE-NNE,
few altocumulus lenticularis distant SW-NNE
Temperature: 50F; Dew Point: 38F; Wind: E at 8G16 kts,
Sea-level pressure: 30.01 ins. Hg, rising then falling and lower
Visibility: 70 miles, light distant haze
6-hr Max temp: 52F
6-hr Min temp: 43F
BHO SA 1755 250 SCT 70 163/50/38/0808G16/001/ FEW SC/CU ENE-NNE
FEW ACSL DSNT SW-NNE LGT DSNT HZ ALQDS/ 8/541 58003 10052 20043
SUMMARY FOR THURSDAY, APRIL 30, 2015

TEMPERATURE (DEGREES F)
MAX…..60   NORMAL…..61
MIN…..42   NORMAL…..43
MEAN….51   NORMAL…..52

DEPARTURE FROM 30-YEAR NORMAL…………………..-1
TOTAL DEPARTURE FOR THE MONTH………………….+20 [+0.5 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..14  DEPARTURE………..+1
TOTAL HEATING UNITS FOR THE MONTH………….528  DEPARTURE……….-23
TOTAL HEATING UNITS FOR THE SEASON………..6271  DEPARTURE………+236
TOTAL HEATING UNITS LAST SEASON TO DATE……6171  DIFFERENCE……..+100

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………21 NE    AT   5:35 A.M.
ASOS…………………..20 E     AT   6:51 P.M.
DAVIS………………….18 NE    AT   5:34 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY………………..14 E     AT   6:53 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..15 E     AT   6:52 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….14 E     AT   7:05 P.M.
AVERAGE WIND SPEED AND DIRECTION………….7.8 NE
ASOS………………….8.6
DAVIS…………………6.9 ENE [063 degrees] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….TRACE  DEPARTURE…..-0.13
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..3.33  DEPARTURE…..-1.22
ASOS……………3.29
TOTAL PRECIPITATION FOR THE YEAR………..17.92  DEPARTURE…..-0.50
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……………TRACE  DEPARTURE…..-3.0
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/…/..              44 SSW RMY 52
4/23 49/34/42/-8/0.00/0/0/…/..              32 W   RMY N/A
4/24 50/32/41/-9/0.00/0.0/…/..              32 NW  RMY 36
4/25 56/30/43/-7/0.00/0.0/…/..              26 NW  RMY 29
4/26 54/39/47/-4/0.00/0.0/…/..              17 NW  RMY N/A
4/27 56/42/49/-2/…./0.0/…/..              30 NW  RMY N/A
4/28 63/39/51/-1/…./0.0/…/..              32 NW  RMY 35
4/29 58/46/52/+0/T/0.0/…/..                 24 ENE RMY 22
4/30 60/42/51/-1/0.00/0.0/…/..              21 NE  RMY N/A

5/1 Low since midnight is 40F, normal low is 43F

DAILY RECORDS FOR APRIL 2015

4/3 – NEW RECORD DAILY HIGH MINIMUM TEMPERATURE: 47F
surpasses the previous record of 46F in 1892

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

RECORDS FOR MAY 1
HIGH 87F IN 1899
LOW 29F IN 1978
PRECIP 2.53 INCHES IN 1921
SNOWFALL TRACE IN 1905,1917,1921,1995.
PEAK GUST 57 MPH NW IN 1974

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

TODAY’S REPORT PREPARED BY: Brian Fitzgerald