Sunday, April 19, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
SUNDAY, APRIL 19, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

VERY COOL TODAY DESPITE FULL STRONG APRIL SUNSHINE
NORTHEAST WINDS HOLDING TEMPS. IN LOW 50’S EARLY AFTERNOON

After 8 consecutive days of above normal temperatures
today will break that string. A low of 40F this morning
and a high of only 53F by early this afternoon will
likely mean a cooler than normal day.
A layer of high cirrus and cirrostratus clouds has been
slowly increasing from the southwest ahead of an
approaching rainstorm expected to arrive by noon tomorrow.

Today’s Observations:

7 A.M.
Weather:  Clear, stratocumulus layer along horizon distant NW-NNW,
cirrostratus layer along horizon distant SW, slowly invading
Temperature: 44F; Dew Point: 33F; Wind: N at 7 kts,
Wind direction variability: NW-NNE:
Sea-level pressure: 30.24 ins. Hg, increasing then more slowly
Visibility: 80 miles, mountain in cloud 70 NW
6-hr Max temp: 44F
6-hr Min temp: 40F
BHO SA 1155 CLR 80 241/44/33/3607/024/ SC LYR ALG HRZN
DSNT NW-NNW CS LYR ALG HRZN DSNT SW INVADING MTN INCLD 70 NW
WND 32V02 8/505 51027 10044 20040

10 A.M.
Weather: Scattered cumulus, except E, cirrostratus distant SSW,
layer slowly invading
Temperature: 50F; Dew Point: 33F; Wind: ENE at 11 kts,
Wind Direction: Variable NNE-E
Sea-level pressure: 30.28 ins. Hg, increasing then more slowly
Visibility: 80 miles
BHO SA 1455 // SCT 80 253/50/33/0811/028/ CU ALQDS XCPT E
CS LYR DSNT SSW-W SLWLY INVDNG WND 03V10/ 8/105 51012

1 P.M.
Weather: Scattered cirrostratus, cirrus, few small cumulus fractus,
cumulus, cirrostratus layer invading, mostly clear sky WNW-E
Temperature: 53F; Dew Point: 33F; Wind: ESE at 5 kts
Sea-level pressure: 30.26 ins. Hg, falling slightly
Visibility: 70 miles, light distant haze
6-hr Max temp: 54F
6-hr Min temp: 44F
BHO SA 1755 250 SCT 300 SCT 70 248/53/33/1205/026/ SML CUFRA AND CU
XCPT OVHD-NE-E CS LYR INVADING MSTLY CLR SKY WNW-E K LYR XTDNG
ALG HRZN NNE-ESE LGT DSNT HZ/ 8/106 58005 10054 20044

SUMMARY FOR SATURDAY, APRIL 18, 2015

TEMPERATURE (DEGREES F)
MAX…..64   NORMAL…..57
MIN…..43   NORMAL…..39
MEAN….54   NORMAL…..48

DEPARTURE FROM 30-YEAR NORMAL…………………..+6
TOTAL DEPARTURE FOR THE MONTH………………….+38 [+1.9 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..11  DEPARTURE………..-6
TOTAL HEATING UNITS FOR THE MONTH………….333  DEPARTURE……….-39
TOTAL HEATING UNITS FOR THE SEASON………..6076  DEPARTURE………+221
TOTAL HEATING UNITS LAST SEASON TO DATE……5952  DIFFERENCE……..+124

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………31 N     AT   5:44 P.M. *
ASOS…………………..34 N     AT   5:42 P.M.
DAVIS………………….35 N     AT   5:41 P.M. RMY 36
FASTEST MILE FOR YESTERDAY………………..24 N     AT   5:42 P.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..24 N     AT   5:43 P.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….24 N     AT   5:42 P.M.
AVERAGE WIND SPEED AND DIRECTION…………10.1 NNE
ASOS…………………10.2
DAVIS…………………9.1 N [360 degrees] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE…..-0.14
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..1.64  DEPARTURE…..-1.30
ASOS……………1.54
TOTAL PRECIPITATION FOR THE YEAR………..16.23  DEPARTURE…..-0.58
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…..-2.5
TOTAL SNOWFALL FOR THE SEASON…………..150.8  DEPARTURE….+88.6

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/+1/0.00/0.0/744/94              39 WNW RMY 48
4/12 68/35/52/+7/0.00/0.0/762/96              23 WNW RMY 23
4/13 69/47/58/+12/0.00/0.0/764/96             35 SSW RMY N/A
4/14 65/51/58/+12/0.05/0.0/072/09             37 SSW RMY N/A
4/15 67/45/56/+9/0.00/0.0/…/..              32 NW  RMY 33
4/16 64/42/53/+6/0.00/0.0/…/..              31 S   RMY 21
4/17 64/45/55/+8/0.05/0.0/…/..              31 SSW RMY 32
4/18 64/43/54/+6/0.00/0.0/…/..              31 N   RMY 36

4/19 low since midnight is 40F normal low is 39F

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 19
HIGH 94 IN 1976 [RECORD FOR MONTH] LOW 21 IN 1890
PRECIP 1.71 IN 1969
SNOWFALL 6.0 IN. IN 1887
PEAK GUST 66 MPH E IN 1984

RECORDS FOR APRIL 20
HIGH 88 IN 1927
LOW 18 IN 1897
PRECIP 1.14 IN 1972
SNOWFALL 2.5 IN. IN 1904, 1972
PEAK GUST 76 MPH WNW IN 1963

TODAY’S REPORT PREPARED BY:  Robert Skilling