BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, APRIL 15, 2015    
ALL TIMES ARE IN EASTERN STANDARD TIME
 
RED FLAG WARNING ISSUED AS TEMPS. RISE AND RELATIVE HUMIDITY 
FALLS UNDER 20%...VISIBILITY 80 MILES FROM THE SUMMIT... 
LAST 2 DAYS AVERAGED 12 DEGREES WARMER THAN NORMAL...
AFTER COLD START THE FIRST 14 APRIL DAYS NOW AVERAGE SLIGHTLY 
ON WARM SIDE...
RELATIVE HUMIDITY DROPS INTO THE TEENS IN VERY DRY AIR MASS
 
The National Weather Service issued a red flag warning for very 
high brush fire danger today.  A small brush fire was observed 
about 4 miles to our NWXN around noon into this afternoon today. 
Temperature had reached the middle 60's but the dew point
was down to 18 degrees and relative humidity at 16% as of
2 P.M. EDT. Winds were from the NW gusting over 20 mph. 
 
-----------------------------------------------------
 
Today's Observations:
 
7 A.M.
Weather: Clear sky, cirrus, few cirrocumulus lenticularis E-SW
Temperature: 49F; Dew Point: 29F; Wind: NNW at 11 kts,
Sea-level pressure: 30.09 ins. Hg, increasing then more quickly
Visibility: 80 miles
6-hr Max temp: 51F
6-hr Min temp: 45F
24--hour precip: 0.04 inch 
BHO SA 1155 CLR 80 190/49/29/3311/009/ CI/FEW CCSL DSNT E-SW/
8/001 53010 MANUAL 70004 ASOS 70005 10051 20045  
 
10 A.M.
Weather: Clear, few cumulus cumulus fractus forming over city N 
Temperature: 61F; Dew Point: 23F; Wind: NNW at 11 kts,
Wind: Direction variable NW-N
Wind: Gust to 17 kts past hour
Sea-level pressure: 30.12 ins. Hg, rising slightly
Visibility: 80 miles light distant haze
BHO SA 1455 CLR 80 199/61/23/3311/012/ OCNL SML CUFRA/CU OVR CTY N
CI/PTCHS DNS CI SE-WSW LGT DSNT HZ WND 31V01 GST 17 KTS PST HR/ 8/102
51009               
  
1 P.M.
Weather: Clear few small cumulus and cumulus fractus,
cirrus and few dense cirrus mostly distant ESE-WSW, small
low level smoke plume/brush fire estimated 4 miles northwest
by north 
Temperature: 65F; Dew Point: 18F; Wind: NW at 14G23kts
Sea-level pressure: 30.12 ins. Hg, falling then more slowly
Visibility: 80 miles
6-hr Max temp: 66F 
6-hr Min temp: 49F
BHO SA 1755 CLR 80 195/65/18/3114G23/011/ FEW SML CU ALQDS
CI/FEW DNS CI DSNT ESE-WSW SML LOW LVL K PLUME/BRUSH FIRE ESTMD
4 MI NW-N/ 8/102 58004 10066 20049   
 
SUMMARY FOR TUESDAY, APRIL 14, 2015
 
TEMPERATURE (DEGREES F)
MAX.....65   NORMAL.....55
MIN.....51   NORMAL.....37
MEAN....58   NORMAL.....46
 
DEPARTURE FROM 30-YEAR NORMAL......................+12
TOTAL DEPARTURE FOR THE MONTH......................+ 9 [+0.4 DEGREES/DAY]
 
HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY...............7  DEPARTURE..........-12
TOTAL HEATING UNITS FOR THE MONTH.............291  DEPARTURE...........-9    
TOTAL HEATING UNITS FOR THE SEASON...........6034  DEPARTURE.........+250
TOTAL HEATING UNITS LAST SEASON TO DATE......5849  DIFFERENCE........+185
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY..................37 SSW AT  12:38 A.M.*   
                   ASOS.......................43 SSW AT  12:23 A.M.    
                   DAVIS......................40 SSW AT  12:23 A.M. N/A
FASTEST MILE FOR YESTERDAY....................31 SSW AT  12:27 A.M.  
MAXIMUM 2-MINUTE ASOS AVERAGE.................33 SSW AT  12:24 A.M.      
MAXIMUM 2-MINUTE DAVIS AVERAGE................31 SSW AT  12:24 A.M.    
AVERAGE WIND SPEED AND DIRECTION............12.9 W 
                   ASOS.....................16.0   
                   DAVIS....................12.2 SW [230 degrees]
* Last of several occurrences...

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M.....0.04  DEPARTURE.....-0.12
                         ASOS...............0.05
TOTAL PRECIPITATION FOR THE MONTH...........1.48  DEPARTURE.....-0.88 
                         ASOS...............1.43
TOTAL PRECIPITATION FOR THE YEAR...........16.07  DEPARTURE.....-0.16
                         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.....-0.1
TOTAL SNOWFALL FOR THE MONTH...............Trace  DEPARTURE.....-2.1 
TOTAL SNOWFALL FOR THE SEASON..............150.8  DEPARTURE....+89.0 
 
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/.../..              39 WNW RMY 48
4/12 68/35/52/+7/0.00/0.0/.../..              23 WNW RMY 23 
4/13 69/47/58/+12/0.00/0.0/.../..             35 SSW RMY N/A
4/14 65/51/58/+12/0.05/0.0/.../..             37 SSW RMY N/A
 
4/15 low since midnight is 45F normal low is 37F
 
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 APRIL 15
HIGH 81 IN 1896
LOW 23 IN 1943
PRECIP 1.75 IN. IN 2007
SNOWFALL 1.0 IN. IN 1916, 1962
PEAK GUST 66 MPH E IN 2007 
 
RECORDS FOR APRIL 16
HIGH 89 IN 2012
LOW 23 IN 1943
PRECIP 2.45 IN. IN 1929
SNOWFALL 2.0 IN. IN 1904, 1962
PEAK GUST 73 MPH E IN 2007
 
TODAY'S REPORT PREPARED BY:  Robert Skilling