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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, MAY 11, 2015 
ALL TIMES ARE IN EASTERN STANDARD TIME

TEMPS HIT 88F ON SUNDAY, MONTHLY DEPARTURE NOW
6.8 DEGREES ABOVE NORMAL

A maximum of 88F was recorded at approximately 3:00 PM
EST, just 5 degrees shy of yesterday's daily record. Heat
and humidity lingered into the evening hours, with 70F
recorded by 11:00 PM EST. With a daily average yesterday
of 74F, this adds a daily departure of +19, bringing the
monthly departure 6.8 above normal. 

Another back door cold front moved in from the coast today, 
causing a wind shift from SW to NE just after the 10:00
AM EST observation. Temperatures tumbled as well, dropping
from 84F at the mid morning observation to 65F just one
hour later.

By the 1:00 PM EST observation fog had begun, limiting 
visibility to 3/4 of a mile in all directions. Temperatures
had fallen as low as 57F following the passage of the front. 

  
Today's Observations:

7 A.M.
Weather: Clear, few altocumulus W-E
Temperature: 72F; Dew Point: 65F; Wind: WSW at 9 kts
Sea-level pressure: 30.12 ins. Hg, rising, then more slowly 
Visibility: 15 miles, thin fog in all directions, hazy
6-hr Max temp: 72F
6-hr Min temp: 65F
24-hr precip: none
BHO SA 1155 CLR 15 201/72/65/2409/012/ FEW AC W-E THN FG ALQDS 
HAZY/ 8/030 51008 10072 20065
  
10 A.M. 
Weather: Scattered cumulus, few stratus fractus distant NE-ENE
Temperature: 83F; Dew Point: 62F; Wind: SW at 7 kts,
Sea-level pressure: 30.18 ins. Hg, falling, rising but still lower 
Visibility: 15 miles, except 10 mile NNW-ESE, thin fog, hazy
BHO SA 1455 40 SCT 15 199/83/62/2307/018/ VSBY NNW-ESE 10 MI FEW 
STFRA DSNT NE-ENE THN FG ALQDS HAZY/ 8/100 55002

1 P.M. 
Weather: Fog
Temperature: 58F; Dew Point: 53F; Wind: NE at 15G24 kts,
Sea-level pressure: 30.11 ins. Hg, falling, then more quickly 
Visibility: 3/4 of a mile, fog
6-Hr Max temp: 84F
6-Hr Min temp: 57F
BHO SA 1755 E2 OVC 3/4F 197/58/53/0515G24/011/ PK WND 0526/19/ 
8//// 58002 10084 20057


SUMMARY FOR SUNDAY, MAY 10, 2015 
  
TEMPERATURE (DEGREES F)
MAX.....88   NORMAL.....65
MIN.....60   NORMAL.....46
MEAN....74   NORMAL.....55

DEPARTURE FROM 30-YEAR NORMAL......................+19
TOTAL DEPARTURE FOR THE MONTH......................+70 [+6.8 DEGREES/DAY] 
 
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............0  DEPARTURE..........-10
TOTAL HEATING UNITS FOR THE MONTH..............53  DEPARTURE..........-60    
TOTAL HEATING UNITS FOR THE SEASON...........6324  DEPARTURE.........+176
TOTAL HEATING UNITS LAST SEASON TO DATE......6255  DIFFERENCE.........+69

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY..............9   DEPARTURE..........+9
TOTAL COOLING UNITS FOR THE MONTH.............14   DEPARTURE.........+11
TOTAL COOLING UNITS FOR THE SEASON............14   DEPARTURE..........+9
TOTAL COOLING UNITS LAST SEASON TO DATE........3   DIFFERENCE........+11

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY..................28 SSW   AT   8:10 P.M.*       
                   ASOS.......................30 SSW   AT   8:11 P.M.         
                   DAVIS......................29 SW    AT   5:01 P.M. RMY 30 
FASTEST MILE FOR YESTERDAY....................22 SSW   AT   5:04 P.M.*  
MAXIMUM 2-MINUTE ASOS AVERAGE.................23 SSW   AT   5:03 P.M.          
MAXIMUM 2-MINUTE DAVIS AVERAGE................23 SSW   AT   5:02 P.M.    
AVERAGE WIND SPEED AND DIRECTION.............14.3 SW  
                   ASOS......................13.8     
                   DAVIS.....................12.9 SW [223 degrees] 
* Last of several occurrences...
 
PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.00  DEPARTURE.....-0.12
                         ASOS...............0.00
TOTAL PRECIPITATION FOR THE MONTH...........0.03  DEPARTURE.....-1.19  
                         ASOS...............0.03 
TOTAL PRECIPITATION FOR THE YEAR...........17.95  DEPARTURE.....-1.69
                         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 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 88/60/74/+19/0.0/0.0/.../..               28 SSW RMY 30

5/11 low since midnight is 65F; 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 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

RECORDS FOR MAY 12
HIGH 88F IN 2001
LOW 29F IN 1907
PRECIP 1.49 INCHES IN 1968
PEAK GUST 76 MPH S IN 1974

TODAY'S REPORT PREPARED BY: Brian Fitzgerald