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

DAILY DISCUSSION AND CLIMATE SUMMARY
SATURDAY, MAY 5, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

A WARM PARTLY CLOUDY DAY ON GREAT BLUE HILL...

We broke one record yesterday for high minimum temperature 
of 67F. The previous record of 66F was set during an early 
season heatwave back in 2001. Today was a bit cooler with an 
observed high of 72F by 1:00 PM which is 9F above the daily 
normal of 63F. Humidity stayed significantly lower than 
yesterday, increasing the visibility from 40 to 80 miles 
today. Winds picked up yesterday afternoon into this morning, 
so far today we had a peak gust of 58 MPH around 1:10 AM.     

PRELIMINARY STATS FOR APRIL 2018
 
TEMPERATURE, Deg. F
Avg. Max. 52.4 [-3.3]
Avg. Min. 34.9 [-2.8]
Mean      43.7 [-3.0]
24-hour corrected mean: 43.1
Max. for month:  73F on 28th
Min. for month:  24F on  9th
 
HEATING DEGREE DAYS
Total heating units:    635  [+84]
Total for the season:  5693 [-342]
Total for last season: 5333

PRECIPITATION, Inches
Total: 6.51 [+1.93]
Greatest in 24 hrs: 2.85 on the 15-16th 

SNOWFALL, Inches
Total: 2.6 [-0.4]
Greatest in 24 hrs: 1.6 in. on 2nd
 
WIND, mph
Avg. uncorrected wind speed: 12.2
Avg. corrected wind speed: 12.6
Prevailing wind direction: WNW at 16%
Peak gust and direction: 56 NW on the 4th 
 
SUNSHINE:
Campbell-Stokes card minutes:N/A
Astronomical total minutes: N/A

Today's Observations:

7 A.M.
Weather: Scattered altocumulus, broken cirrostratus, few cumulus
distant along the horizon.    
Temperature: 56F; Dew Point: 37F; Wind: SW at 14G24 kts 
Sea-level pressure: 29.96 ins. Hg, rising unsteadily    
Visibility: 80 miles
6-hr Max temp: 69F
6-hr Min temp: 54F
24-hr precip:  0.02 ins. 
24-hr snowfall: 0.0 ins.  
Snow depth: 0 ins.
BHO SA 1155 90 SCT 130 SCT E250 BKN 80 145/56/37/2914G24/996/ 
FEW CU DSNT ALNG HRZN SW-NW/ 8/268 52041 MANUAL 70002 ASOS 
70002 10069 20054 

10 A.M.
Weather: Scattered cirrostratus, few cumulus distant along
the horizon.
Temperature: 63F; Dew Point: 39F; Wind: W at 9G21 kts
Sea-level pressure: 30.02 ins. Hg, rising, then more slowly   
Visibility: 80 miles 
3-hr precip: 0.00 ins.  
3-hr snowfall: 0.0 ins.
BHO SA 1455 250 SCT 80 165/63/39/2809G21/002/ FEW CU DSNT 
ALNG HRZN SW-NNW FEW AC NE-SE/ 8/188 51020 

1 P.M.
Weather: Scattered altocumulus, broken cirrostratus. 
Temperature: 72F; Dew Point: 39F; Wind: W at 08G18 kts
Sea-level pressure: 30.03 ins. Hg, rising, then more slowly
Visibility: 80 miles 
6-hr Max temp: 72F
6-hr Min temp: 56F
6-hr precip:   0.00 ins
6-hr snowfall: 0.0 ins.   
Snow depth: 0 ins.
BHO SA 1755 150 SCT E250 BKN 80 168/72/39/2608G18/003/
8/038 51003 10072 20056
 

     
SUMMARY FOR FRIDAY, MAY 4, 2018

TEMPERATURE (DEGREES F)
MAX.....81   NORMAL.....63
MIN.....67   NORMAL.....44
MEAN....74   NORMAL.....54

DEPARTURE FROM 30-YEAR NORMAL.........................+20 
TOTAL DEPARTURE FOR THE MONTH.........................+66 [+16.3 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY..............0   DEPARTURE.........-12
TOTAL HEATING UNITS FOR THE MONTH.............13   DEPARTURE.........-36
TOTAL HEATING UNITS FOR THE SEASON..........5706   DEPARTURE........-377
TOTAL HEATING UNITS LAST SEASON TO DATE.....5386   DIFFERENCE.......+320

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY...............9   DEPARTURE...........9
TOTAL COOLING UNITS FOR THE MONTH..............32   DEPARTURE.........+31
TOTAL COOLING UNITS FOR THE SEASON.............32   DEPARTURE.........+29
TOTAL COOLING UNITS LAST SEASON TO DATE........20   DEPARTURE.........+12

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...................39 SW  AT 8:18 P.M. 
                   AERO........................37 SSW AT 6:22 P.M.* 
                   ASOS........................41 S   AT 8:18 P.M.
                   DAVIS.......................40 M   AT 8:18 P.M.** RMY N/A
FASTEST MILE FOR YESTERDAY.....................30 SSW AT 8:07 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..................31 S   AT 8:06 P.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE.................31 M   AT 8:06 P.M.**
AVERAGE WIND SPEED AND DIRECTION.............14.3 SSW
                   ASOS......................13.7 
                   DAVIS.....................13.3 M**
*  Last of multiple occurrences
** Davis direction malfunctioning 

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.02  DEPARTURE......-0.10
                         ASOS..............0.02
TOTAL PRECIPITATION FOR THE MONTH..........0.18  DEPARTURE......-0.31
                         ASOS..............0.17  
TOTAL PRECIPITATION FOR THE YEAR..........25.49  DEPARTURE......+6.60
                         ASOS.............27.09

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 APRIL 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
*   : Estimated data 

4/01 58/33/46/+5/0.00/0.0/336/44   45 SSW AERO 43 SSW RMY N/A  
4/02 38/30/34/-7/0.13/1.6/077/10   20 SSW AERO 15 SSW RMY 17
4/03 48/30/39/-3/0.54/0.0/238/31   28 SSE AERO 25 SSE RMY 25
4/04 54/36/45/+3/0.21/0.0/000/00   56 WNW AERO 56 WNW RMY 54
4/05 40/27/34/-9/0.00/0.0/760/98   53 WNW AERO 53 WNW RMY 52 
4/06 41/25/33/-10/0.25/1.0/156/20  37 S   AERO 36 S   RMY 38
4/07 46/32/35/-4/0.00/0.0/312/40   32 WNW*AERO 35 WNW RMY 34
4/08 41/29/35/-9/0.00/0.0/290/37   35 WNW*AERO 31 WNW RMY 34
4/09 45/24/35/-9/0.00/0.0/715/01   28 WNW AERO 25 WNW RMY 29
4/10 39/31/35/-10/T/T/000/00       14 SSW AERO 13 SSW RMY N/A
4/11 48/29/39/-6/T/0.0/364/46      24 SSE AERO 23 SSE RMY 25 
4/12 61/33/47/+2/0.03/0.0/500/63   39 SSW AERO 38 SSW RMY 41 
4/13 65/47/56/+10/T/0.0/096/12     37 SSW AERO 37 SSW RMY N/A
4/14 51/36/44/-2/0.00/0.0/328/41   33 ENE AERO 31 ENE RMY N/A
4/15 36/30/33/-14/0.32/T/000/00    39 ENE AERO 39 ENE RMY N/A
4/16 55/32/44/-3/2.63/000/00       41 ENE AERO 43 ENE RMY 41
4/17 48/36/42/-5/0.00/0.0/210/26   37 W   AERO 33 W   RMY 37
4/18 53/32/43/-5/0.00/0.0/633/78   35 W   AERO 31 W   RMY 34
4/19 41/34/38/-10/0.22/T/000/00    28 WNW AERO 25 WNW RMY N/A 
4/20 52/31/42/-7/0.00/0.0/522/64   34 NW  AERO 33 NW  RMY 36
4/21 60/33/47/-2/0.00/0.0/811/99   28 NW  AERO 26 NW  RMY 29
4/22 61/36/49/0/0.00/0.0/821/100   25 NW  AERO 24 NW  RMY 26 
4/23 62/40/51/+1/0.00/0.0/816/99   25 S   AERO 25 S   RMY 26
4/24 67/39/53/+3/0.00/0.0/645/78   31 S   AERO 29 S   RMY 32
4/25 57/47/52/+2/..../0.0/000/00   32 SE  AERO 32 SE  RMY 33 
4/26 66/48/57/+6/..../0.0/308/37   36 WNW AERO 35 WNW RMY 37 
4/27 60/45/53/+2/..../0.0/.../..   18 W   AERO 15 W   RMY N/A
4/28 73/47/60/+8/0.00/0.0/.../..   25 S   AERO 21 S   RMY 25
4/29 59/38/49/-3/0.04/0.0/.../..   32 SW  AERO 26 SW  RMY 31
4/30 46/36/41/-11/0.37/0.0/.../..  23 WSW AERO 16 WSW RMY N/A

DAILY RECORDS FOR APRIL 2018

4/16/18: NEW DAILY RECORD MAXIMUM PRECIPITATION OF 2.63 INS.
         PREVIOUS RECORD WAS 2.45 INS. SET IN 1929

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

5/1 65/39/52/-1/0.00/0.0/.../..    25 WNW AERO 21 WNW RMY 25
5/2 88/59/74/+21/0.00/0.0/.../..   37 WSW AERO 29 WSW RMY 35 
5/3 90/67/70/+26/..../0.0/.../..   36 SW  AERO 32 WSW RMY 36  
5/4 84/67/74/+20/..../0.0/.../..   39 SSW AERO 37 SSW RMY N/A

5/5  Low temp since midnight is 54F; normal low is now 45F

DAILY RECORDS FOR MAY 2018

5/03/17: DAILY RECORD HIGH MINIMUM TEMPERATURE OF 67F,
         BREAKS PREVIOUS RECORD OF 66F SET IN 2001

5/04/17: 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 5
HIGH 92F IN 1949
LOW 30F IN 1891
PRECIP 2.74 INCHES IN 1922
SNOWFALL 3.0 INCHES IN 1917
PEAK GUST 58 MPH S IN 1966 & 58e MPH SW IN 1976

RECORDS FOR MAY 6
HIGH 90F IN 1930
LOW 29F IN 1891
PRECIP 1.04 INCHES IN 1890
SNOWFALL TRACE IN 1917,1996
PEAK GUST 65 MPH SSE IN 1989

TODAY'S REPORT PREPARED BY: Kaitlin Geagan & Devin Richardt