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

DAILY DISCUSSION AND CLIMATE SUMMARY
THURSDAY, MAY 24, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

THUNDERSTORM IMPACTED BLUE HILL LAST EVENING
SUNNY AND PLEASANT TODAY

A somewhat unexpected batch of showers and thunderstorms moved through eastern
Massachusetts yesterday evening. Here at Blue Hill, 0.06 ins. of rain were
measured from this. Winds picked up and shifted as these storms passed, with a gust 
to 33mph. This followed a warmer than average day, with a high temperature 
yesterday of 82F compared to the average high of 68F. 

Today's weather has been calm and more seasonable, though still a little warmer
than average. The high temperature so far is 72F, after a morning low of 51F. The 
air has dried out today, with the dew point falling into the 40s, providing a 
pleasant feel outside. Winds have been very light today, averaging under 5mph since 
sunrise, with the direction variable. Some low clouds early this morning dissipated 
quickly by mid-morning, yielding plenty of sunshine. A visually impressive patch of 
lenticular clouds moved through the area early this afternoon, and were observed
to gradually flatten and spread out as they passed. 

Today's Observations:

7 A.M.
Weather: Broken stratocumulus/stratus fractus, thin broken cirrus, few stratus 
fractus below summit NE, thin fog
Temperature: 57F; Dew Point: 53F; Wind: estimated N at 3 kts,
Wind: Light and variable
Sea-level pressure: 30.10 ins. Hg, rising, then more slowly 
Visibility: 10 miles, except 20 miles SSW-W
6-hr Max temp: 57F
6-hr Min temp: 51F
24-HR Precip: 0.06 ins.
BHO SA 1155 E5 BKN 300 BKN 10 192/57/53/E3503/010/ FEW STFRA BLO SMT NE 
THN FG ALQDS VSBY SSW-W 20 WND L/V/ 8/501 51023 MANUAL 70006 ASOS 70005 
10057 20051

10 A.M.
Weather: Scattered cirrus, few cumulus all quadrants except NE and S-SW
Temperature: 66F; Dew Point: 51F; Wind: estimated NW at 3 kts,
Wind: Light and variable 
Sea-level pressure: 30.12 ins. Hg, rising, then more slowly
Visibility: 65 miles, light distant haze
3-hr Precip: 0.00 ins.
BHO SA 1455 250 SCT 65 197/66/51/E3203/012/FEW CU ALQDS XCPT NE AND S-SW 
LGT DSNT HZ WND L/V/ 8/101 51007

1 P.M.
Weather: Scattered cirrus (partly thin), few cumulus distant SSE and NNW-N,
few altocumulus/altocumulus lenticularis SE-NNW
Temperature: 71F; Dew Point: 45F; Wind: estimated NNW at 5 kts,
Wind: Light and variable 
Sea-level pressure: 30.10 ins. Hg, rising then falling
Visibility: 30 miles, distant haze
6-hr Max temp: 72F
6-hr Min temp: 57F
6-hr precip:  0.00 ins.
BHO SA 1755 280 SCT 30 193/71/45/E3405/010/ FEW CU DSNT SSE AND NNW-N 
FEW AC/ACSL SE-NNW CI LYR PRTLY THN DSNT HZ WND L/V/ 8/141 58006 10072 20057    

SUMMARY FOR WEDNESDAY, MAY 23, 2018

TEMPERATURE (DEGREES F)
MAX.....82   NORMAL.....68
MIN.....51   NORMAL.....50
MEAN....67   NORMAL.....59

DEPARTURE FROM 30-YEAR NORMAL.........................+8
TOTAL DEPARTURE FOR THE MONTH.......................+117 [+4.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............0   DEPARTURE..........-7
TOTAL HEATING UNITS FOR THE MONTH............129   DEPARTURE.........-93
TOTAL HEATING UNITS FOR THE SEASON..........5822   DEPARTURE........-434
TOTAL HEATING UNITS LAST SEASON TO DATE.....5587   DIFFERENCE.......+235

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............2   DEPARTURE..........+1
TOTAL COOLING UNITS FOR THE MONTH..............39   DEPARTURE.........+27
TOTAL COOLING UNITS FOR THE SEASON.............39   DEPARTURE.........+25
TOTAL COOLING UNITS LAST SEASON TO DATE........56   DEPARTURE.........-17

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................33 NNW  AT  8:10 P.M.
                   AERO........................33 NNW  AT  8:10 P.M. 
                   ASOS........................33 NW   AT  8:10 P.M.
                   DAVIS.......................34 M    AT  8:10 P.M.** RMY 34
FASTEST MILE FOR YESTERDAY.....................22 NNW  AT  8:11 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................23 NNW  AT  8:11 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................24 M    AT  8:10 P.M.**
AVERAGE WIND SPEED AND DIRECTION..............9.5 NW
                   ASOS.......................9.6
                   DAVIS......................9.4 M**
** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.06  DEPARTURE......-0.09
                         ASOS..............0.05
TOTAL PRECIPITATION FOR THE MONTH..........1.88  DEPARTURE......-1.02
                         ASOS..............1.85  
TOTAL PRECIPITATION FOR THE YEAR..........27.19  DEPARTURE......+5.92
                         ASOS.............28.77

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..............92.8  DEPARTURE.......+30.0

PRELIMINARY CLIMATE SUMMARY FOR MAY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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

5/01 65/39/52/-1/0.00/0.0/625/74    25 WNW AERO 21 WNW RMY 25
5/02 88/59/74/+21/0.00/0.0/584/69   37 WSW AERO 29 WSW RMY 35 
5/03 90/67/79/+26/..../0.0/433/51   36 SW  AERO 32 WSW RMY 36  
5/04 84/67/74/+20/..../0.0/102/12   39 SSW AERO 37 SSW RMY N/A
5/05 73/54/64/+10/0.00/0.0/615/72   56 W   AERO 55 W   RMY N/A
5/06 65/48/57/+3/0.21/0.0/000/00    24 NE  AERO 18 NE  RMY 21
5/07 62/49/56/+1/0.00/0.0/713/83    26 ENE AERO 22 NE  RMY 24
5/08 73/46/60/+5/0.00/0.0/852/99    25 SSE AERO 21 ESE RMY 23 
5/09 74/48/61/+6/..../0.0/768/89    23 ESE AERO 18 ESE RMY 21 
5/10 73/48/61/+6/..../0.0/.../..    33 S   AERO 30 S   RMY 32 
5/11 70/51/61/+5/..../0.0/.../..    26 WNW AERO 24 NW  RMY 28
5/12 51/47/49/-7/0.19/0.0/.../..    25 E   AERO 23 E   RMY N/A
5/13 58/46/52/-4/T/0.0/.../..       20 S   AERO 17 S   RMY 16 
5/14 73/47/60/+3/0.00/0.0/.../..    23 S   AERO 18 S   RMY 21
5/15 83/54/69/+12/..../0.0/.../..   51 NW  AERO 50 NW  RMY 54 TSTM
5/16 56/49/53/-4/T/0.0/.../..       32 ENE AERO 28 ENE RMY 30
5/17 72/51/62/+5/0.02/0.0/.../..    17 SW  AERO 14 SW  RMY N/A
5/18 62/43/53/-5/0.00/0.0/.../..    35 ENE AERO 33 ENE RMY N/A
5/19 57/43/50/-8/.../0.0/.../..     22 E   AERO 17 E   RMY N/A
5/20 77/54/66/+8/.../0.0/.../..     33 SW  AERO 31 SW  RMY 33 TSTM
5/21 77/52/65/+6/0.00/0.0/.../..    22 W   AERO 18 W   RMY 20
5/22 68/51/60/+1/0.04/0.0/.../..    23 SSW AERO 21 S   RMY 22
5/23 82/51/67/+8/0.06/0.0/.../..    33 NNW AERO 33 NNW RMY 34 TSTM

5/24 Low temp since midnight is 51F; normal low is now 50F

DAILY RECORDS FOR MAY 2018

5/03/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

5/04/18: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

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

RECORDS FOR MAY 24
HIGH 92F IN 1964
LOW 35F IN 1956
PRECIP 2.13 INS IN 1951
PEAK GUST 54 MPH NNE IN 2005

RECORDS FOR MAY 25
HIGH 91F IN 2007
LOW 37F IN 1967
PRECIP 3.73 INS IN 1967
PEAK GUST 83 MPH NE IN 1967 (RECORD FOR MAY)

TODAY'S REPORT PREPARED BY: Jonathan O'Brien