Saturday, May 13, 2017

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 13, 2017
ALL TIMES ARE IN EASTERN STANDARD TIME

SKIES STAY OVERCAST ALL DAY, WINDS REMAIN LIGHT

Despite clearing fog and dissipating morning drizzle,
skies remained overcast all morning with low clouds.
By afternoon, the low clouds had broken into scattered
cumulus, but higher clouds still obscured the sky.
Temperatures were again in the upper 50s today and had
reached 56F by 1:00PM EST.  Light winds had become
easterly during the afternoon after beginning the day
out of the south.

Today’s Observations:

7 A.M.
Weather: Overcast nimbostratus
Temperature: 44F; Dew Point: 42F; Wind: ESE at 6 kts,
Wind Speed: Light
Sea-level pressure: 30.03 ins. Hg, rising then steady
Visibility: 10 miles, distant fog in all directions
6-hr Max temp: 45F
6-hr Min temp: 41F
24-hr precip: 0.01 in.
BHO SA 1155 E4 OVC 10L- 169/44/42/1206/003/ DSNT FG ALQDS
PCPN VRY LGT WND LGT/ 8/6// 51006 MANUAL 70001 ASOS 70001
10045 20041

10 A.M.
Weather: Broken stratocumulus, overcast stratus
Temperature: 51F; Dew Point: 41F; Wind: SE at 8 kts
Sea-level pressure: 30.03 ins. Hg, falling unsteadily
Visibility: 70 miles, except 35 miles WSW-NW, distant fog WSW-NW
3-hr precip: Trace
BHO SA 1455 E6 BKN 17 OVC 70 168/51/41/1308/003/ VSBY WSW-NW 35
DSNT FG WSW-NW/ 8/6// 58001 MANUAL 600//

1 P.M.
Weather: Scattered cumulus, overcast altostratus
Temperature: 55F; Dew Point: 42F; Wind: E at 8 kts
Sea-level pressure: 29.99 ins. Hg, falling, then more quickly
Visibility: 60 miles, distant fog in all directions
6-hr Max temp: 56F
6-hr Min temp: 43F
6-hr precip: Trace
BHO SA 1755 49 SCT E130 OVC 60 156/55/42/1008/999/ DSNT FG ALQDS/
8/12/ 58012 MANUAL 600// 10056 20043

SUMMARY FOR FRIDAY, MAY 12, 2017

TEMPERATURE (DEGREES F)
MAX…..57   NORMAL…..65
MIN…..41   NORMAL…..47
MEAN….49   NORMAL…..56

DEPARTURE FROM 30-YEAR NORMAL…………………….-7
TOTAL DEPARTURE FOR THE MONTH……………………-43 [-3.8 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..16   DEPARTURE……….+6
TOTAL HEATING UNITS FOR THE MONTH………….170   DEPARTURE………+37
TOTAL HEATING UNITS FOR THE SEASON………..5503   DEPARTURE……..-664
TOTAL HEATING UNITS LAST SEASON TO DATE……5160   DIFFERENCE…….+343

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….21 NE  AT 9:36 A.M.
AERO……………………20 NE  AT 9:36 A.M.
ASOS……………………20 NE  AT 9:41 A.M.
DAVIS…………………..18 ENE AT 8:03 A.M. RMY 19
FASTEST MILE FOR YESTERDAY…………………12 NE  AT 9:36 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15 ENE AT 9:37 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..13 ENE AT 9:37 A.M.
AVERAGE WIND SPEED AND DIRECTION…………..7.6 NE
ASOS…………………..8.6
DAVIS………………….6.3 NE [050 deg.]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M….0.01  DEPARTURE……-0.12
ASOS…………..0.01
TOTAL PRECIPITATION FOR THE MONTH……….1.23  DEPARTURE……-0.24
ASOS…………..1.28
TOTAL PRECIPITATION FOR THE YEAR……….22.04  DEPARTURE……+2.02
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

5/1  50/43/47/-6/T/…/..                  21 N   AERO 18 N   RMY 22
5/2  65/42/54/+1/0.26/…/..               41 W   AERO 44 W   RMY 43
5/3  52/42/53/0/0.00/…/..                37 WNW*AERO 39 WNW RMY 40
5/4  65/40/53/-1/0.00/…/..               23 S   AERO 23 S   RMY 24
5/5  51/44/48/-6/0.73/…/..               28 E   AERO 28 E   RMY N/A
5/6  65/50/58/+4/0.23/…/..               46 SSE AERO 48 SSE RMY 49
5/7  63/47/55/0/T/…/..                   35 S   AERO 38 S   RMY 39
5/8  54/38/46/-9/T/…/..                  29 WSW AERO 29 WSW RMY 32
5/9  53/36/45/-10/T/…/..                 20 ESE AERO 17 ESE RMY 19
5/10 57/42/50/-5/0.00/…/..               17 NNE AERO 16 NW  RMY N/A
5/11 58/45/52/-4/0.00/…/..               23 NE* AERO 23 NE  RMY 23
5/12 57/41/49/-7/0.01/…/..               21 NE  AERO 20 NE  RMY 19

5/13 Low temp since midnight is 41F; normal low is now 47F

DAILY RECORDS FOR MAY

None so far.

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

RECORDS FOR MAY 13
HIGH 85F IN 1947
LOW 35F IN 1914, 2005
PRECIP 2.39 INCHES IN 2006
PEAK GUST 49 MPH NNW IN 1965

RECORDS FOR MAY 14
HIGH 85F IN 1961
LOW 33F IN 1895
PRECIP 1.93 INCHES IN 2006
PEAK GUST 53 MPH S IN 2009

TODAY’S REPORT PREPARED BY: Cecilia Borries-Strigle