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

DAILY DISCUSSION AND CLIMATE SUMMARY
TUESDAY, APRIL 9, 2013   
ALL TIMES ARE IN EASTERN STANDARD TIME
    
TEMPERATURE REACHES LOWER 70S THIS AFTERNOON;
WARMTH OF PAST 2 DAYS PUSHES APRIL DEPARTURE INTO POSITIVE TERRITORY

Yesterday's warmth all but eliminated the remaining negative temperature
departure for the month of April.  Today's warmth is picking up where
yesterday's warmth left off.  It's been a few degrees warmer today, with
an afternoon high pushing into the lower 70s.  This is the first 70+
degree temperature reading since October 20, 2012.  Today's average
temperature will likely finish close to 15 degrees above the 30-year
normal, pushing April solidly into positive temperature departure
territory.

Early this morning, a few light rain showers and even a brief thunderstorm
brought only a trace of precipitation to the summit.  The summit soon
became shrouded in fog, reducing visibility to 1/4 mile.  The fog began
dissipating rather quickly, with the first glimpse of sun just before
9 A.M. EDT.

Winds that were SSE early this morning have become W this afternoon with
the passage of a cold front shortly before 11 A.M. EDT.  Winds are gusting
in the 25-35 mph range, with a peak wind for the day so far of 35 mph.

Today's observations:

7 A.M.
Weather: Sky obscured by dense fog, stratus drifting over summit
Temperature: 47F; Dew Point: 46F; Wind: S at 10 kts.
Sea-level pressure: 29.91 ins. Hg, rising then falling
Visibility: 1/4 mile, dense fog
24-hr precip: Trace
6-hr precip: Trace
6-hour min. temp: 45F
BHO SA 1155 W3 X 1/4F 130/47/46/1910/991/ STRA DRFTNG OVR SMT/ 8////
58014 MANUAL 7000/ MANUAL 6000/ 10047 20045

10 A.M. 
Weather: Scattered altocumulus, scattered cirrostratus, few cumulus/
cumulus fractus forming distant WSW-NNE, cirrostratus distant N-NE,
thin smoke/haze layer distant all quadrants, hazy
Temperature: 62F; Dew Point: 50F; Wind: W at 10 kts,
Wind: Direction variable SW-WNW
Wind: Direction gradually veering (clockwise)
Sea-level pressure: 29.89 ins. Hg, falling
Visibility: 20 miles, lower W-N-E, higher E-S-W, hazy
BHO SA 1455 140 SCT 200 SCT 20 123/62/50/2710/989/ FEW CU/CUFRA FRMG
DSNT WSW-NNE CS DSNT N-NE THN K/HZ LYR DSNT ALQDS HAZY VSBY W-N-E LWR
E-S-W HIER WND 22V30 WND GRDLY VEERING/ 8/178 55007

1 P.M. 
Weather: Scattered cumulus/cumulus fractus/stratocumulus, scattered thin
cirrus, broken thin cirrus, cumulus/cumulus fractus/stratocumulus mostly
distant NW-ENE, few small cumulus/cumulus fractus E-S-NW, stratocumulus
distant NNW-NNE, thin smoke/haze layer distant N-E-S, distant haze
Temperature: 71F; Dew Point: 46F; Wind: W at 17G27 kts,
Wind: Peak wind 29 kts. from the W at 12:17 P.M.
Wind: Direction variable WSW-NW
Sea-level pressure: 29.89 ins. Hg, falling then rising
Visibility: 60 miles, NW 70 miles, N-E-SW lower, distant haze
6-hour max. temp: 71F
BHO SA 1755 40 SCT 250 ñSCT 300 ñBKN 60 123/71/46/2817G27/989/
CU/CUFRA/SC MSTLY DSNT NW-ENE FEW SML CU/CUFRA E-S-NW SC DSNT NNW-NNE
THN K/HZ LYR DSNT N-E-S DSNT HZ VSBY NW 70 N-E-SW LWR PK WND 2729/17
WND 25V32/ 8/501 55000 10071 20047

WEATHER SUMMARY FOR MONDAY, APRIL 8

TEMPERATURE (DEGREES F)
MAX.....65     NORMAL.....53
MIN.....43     NORMAL.....35					
MEAN....54     NORMAL.....44   
 
DEPARTURE FROM 30-YEAR NORMAL...................+10
TOTAL DEPARTURE FOR THE MONTH....................+1 [-0.1 DEGREE/DAY]
 
HEATING DEGREE DAYS  
TOTAL HEATING UNITS FOR YESTERDAY............11	  DEPARTURE.........-10
TOTAL HEATING UNITS FOR THE MONTH...........180   DEPARTURE..........-1
TOTAL HEATING UNITS FOR THE SEASON.........5200   DEPARTURE........-465
TOTAL HEATING UNITS LAST SEASON TO DATE....4456   DIFFERENCE.......+744

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY...............29 SSW AT 12:09 A.M.
                   AERO....................22 SSW AT 12:09 A.M.
                   ASOS....................28 SSW AT 12.09 A.M.
                   DAVIS...................28 SSW AT  12-1 A.M. RMY: N/A
THE FASTEST MILE FOR YESTERDAY.............21 SSW AT 12:08 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE..............21 SSW AT  1:33 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE.............20 SSW AT  12-1 A.M.
AVERAGE WIND SPEED AND DIRECTION.........11.3 SE
                   ASOS..................10.3
                   DAVIS.................10.7 SSW [202 deg]

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M...Trace  DEPARTURE...........-0.16
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........0.34  DEPARTURE...........-1.01
                         ASOS..............0.35
TOTAL PRECIPITATION FOR THE YEAR..........14.43  DEPARTURE...........-0.92
                         ASOS..............N/A*
*ASOS malfunctioned during storm on 2/8-9, leading to erroneous totals
				
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M.........0.0   DEPARTURE............-0.2
TOTAL SNOWFALL FOR THE MONTH.............Trace   DEPARTURE............-1.4
TOTAL SNOWFALL FOR THE SEASON.............99.0   DEPARTURE...........+37.9

PRELIMINARY CLIMATE SUMMARY FOR APRIL 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
AERO: Aerovane wind recording system gust
RMY:  RMY = R.M. Young wind gust recording system added 8/9/2011 
TSTM: Thunderstorm day (thunder heard some time during day)
....: Data not yet available, records not finalized

4/1  61/31/46/+5/0.34/0.0/458/60     40 W   AERO 44 MPH WNW RMY 46
4/2  40/27/34/-7/T/T/460/460/60      45 W   AERO 42 MPH W   RMY 47
4/3  45/27/36/-6/0.00/0.0/755/98     44 W   AERO 43 MPH W   RMY 47
4/4  55/26/41/-1/0.00/0.0/719/93     30 WSW AERO 27 MPH WSW RMY 31
4/5  59/36/48/+5/0.00/0.0/403/52     33 NNW AERO 28 MPH NNW RMY 38
4/6  47/30/39/-4/0.00/0.0/747/96     38 NW  AERO 35 MPH NW  RMY 40  
4/7  52/31/42/-1/0.00/0.0/.../..     51 S   AERO 46 MPH S   RMY 50
4/8  65/43/54/+10/T/0.0/.../..       29 SSW AERO 22 MPH SSW RMY N/A

4/9  the morning low temp: 45F; the normal low is now 35F

DAILY RECORDS FOR APRIL 2013
None so far.

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

RECORDS FOR APRIL 9
HIGH 83 IN 1991
LOW 18 IN 1888
PRECIP 2.38 IN. IN 1935
SNOWFALL 11.0 IN. IN 1917
PEAK GUST 72 MPH WNW IN 1962

RECORDS FOR APRIL 10
HIGH 83 IN 1922
LOW 20 IN 1985
PRECIP 2.40 IN. IN 1935
SNOWFALL 10.1 IN. IN 1996
PEAK GUST 66 MPH WNW IN 1967

TODAY'S REPORT PREPARED BY: Sean Fankhauser