Monday, December 21, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, DECEMBER 21, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

TEMPS DIP BELOW FREEZING BY MIDNIGHT, WARM UP COMMENCES
YET AGAIN THIS WEEK, WITH GUSTY SSW WINDS

Incredibly, yesterday’s average temperature of 34F was still 4
degrees warmer than the normal temperatures for that date.
Today’s daily normal maximum of 37F was already met by this
morning’s 7:00 AM EST observation. Sunday marks the 19th
consecutive day with above normal temperatures this month.

Gusty SSW winds have been consistently gusting between 20 and 40 MPH
for the majority of the morning as temperatures continued to
climb. By the 1:00 PM EST skies were overcast with cloud layers
expanding at all levels into the region. Winds were still gusty with
temperatures continuing to climb to a maximum so far of 49F.

So far this season, there has been no measurable snow on Blue Hill.
This season is now the fifth latest on record for the first occurrence
of measurable snowfall with no snow likely over the next week.

BHO Latest First Measurable Snowfall, (1885-2014)

1) January 13, 2000   (7.0 inches)
2) January 1, 1954    (0.8 inches)
3) December 29, 1941  (0.4 inches)
4) December 22, 1998  (0.6 inches)
5) December 16, 1973  (0.4 inches)
6) December 15, 1891  (0.3 inches)

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, broken cirrocumulus,
thin broken cirrus
Temperature: 37F; Dew Point: 29F; Wind: SSW at 22G29 kts
Peak Wind: 31 knots SSW at 6:03 AM EST
Sea-level pressure: 30.29 ins. Hg, falling, then more slowly
Visibility: 30 miles, thin fog in all directions
6-hr Max temp: 37F
6-hr Min temp: 32F
24-hr precip: 0.00 ins
BHO SA 1155 160 SCT E200 BKN 250 -BKN 30 259/37/29/2122G29/029/
THN FG ALQDS PK WND 2031/03/ 8/059 56017 10037 20032

10 A.M.
Weather: Scattered altocumulus lenticularis, thin overcast
of cirrostratus
Temperature: 45F; Dew Point: 34F; Wind: SSW at 20G28 kts
Peak Wind: 29 knots SSW at 9:02 AM EST
Sea-level pressure: 30.26 ins. Hg, falling, then more quickly
Visibility: 60 miles, except 30 miles thin fog, light distant haze
BHO SA 1455 160 SCT E250 -OVC 60 248/45/34/2120G28/026/
VSBY SE-WSW 30 MI THN FG ALQDS LGT DSNT HZ ALQDS
PK WND 2029/02/ 8/047 58011

1 P.M.
Weather: Scattered cirrostratus expanding, overcast
translucent cirrostratus, few cumulus fractus distant SSE-SW,
sun dimly visible
Temperature: 49F; Dew Point: 36F; Wind: SSW at 20G30 kts
Peak Wind: 32 knots SW at 12:27 PM EST
Sea-level pressure: 30.16 ins. Hg, falling rapidly
Visibility: 70 miles, light distant haze
6-hr Max Temp: 49F
6-hr Min Temp: 37F
BHO SA 1755 200 SCT E250 OVC 70 212/49/36/2020G30/016/
FEW CUFRA DSNT SSE-SW LGT DSNT HZ ALQDS PRESFR
SUN DMLY VSBL PK WND 2232/27/ 8/706 58036 10049 20037

SUMMARY FOR SUNDAY, DECEMBER 20, 2015

TEMPERATURE (DEGREES F)
MAX…..40   NORMAL…..38
MIN…..28   NORMAL…..22
MEAN….34   NORMAL…..30

DEPARTURE FROM 30-YEAR NORMAL………………….+4
TOTAL DEPARTURE FOR THE MONTH………………..+216  [+10.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..31   DEPARTURE……….-4
TOTAL HEATING UNITS FOR THE MONTH………….420   DEPARTURE……..-218
TOTAL HEATING UNITS FOR THE SEASON………..1422   DEPARTURE……..-478
TOTAL HEATING UNITS LAST SEASON TO DATE……1758   DIFFERENCE…….-336

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….24  W   AT 12:03 A.M.
ASOS……………………23  WSW AT 12:03 A.M.
DAVIS…………………..23  W   AT 12:22 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………17  W   AT 12:02 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………18  W   AT 12:04 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..17  W   AT 12:04 A.M.
AVERAGE WIND SPEED AND DIRECTION………….11.0 W
ASOS………………….10.9
DAVIS………………….9.9 W [265 Deg.] * Last of several occurrences…

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M…..0.00  DEPARTURE……-0.16
ASOS……………0.00
TOTAL PRECIPITATION FOR THE MONTH………..1.60  DEPARTURE……-1.64
ASOS……………1.61
TOTAL PRECIPITATION FOR THE YEAR………..41.02  DEPARTURE…..-10.76
ASOS…………….N/A ***
*** ASOS annual total not available due to erroneous readings

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M……….0.0  DEPARTURE……-0.6
TOTAL SNOWFALL FOR THE MONTH…………….0.0  DEPARTURE……-7.8
TOTAL SNOWFALL FOR THE SEASON………….TRACE  DEPARTURE…..-10.4

PRELIMINARY CLIMATE SUMMARY FOR DECEMBER CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/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

12/1  42/30/36/-1/…./0.0/000/00           19 NNE RMY 19
12/2  53/37/45/+9/…./0.0/000/00           25 SSE RMY 25
12/3  53/37/45/+9/…./0.0/162/29           43 WNW RMY 42
12/4  47/32/40/+5/0.00/0.0/444/80           32 NW  RMY 32
12/5  50/33/42/+7/0.00/0.0/548/99           21 W   RMY N/A
12/6  57/35/46/+11/0.00/0.0/531/96          22 SW  RMY N/A
12/7  54/37/46/+12/0.00/0.0/353/64          31 NE  RMY N/A
12/8  42/35/39/+5/0.01/0.0/000/00           32 NE  RMY 31
12/9  44/34/39/+5/…./0.0/044/08           28 SSE RMY N/A
12/10 57/41/49/+16/T/0.0/209/38             29 SE  RMY N/A
12/11 56/44/50/+17/0.00/0.0/049/09          28 SSW RMY 28
12/12 59/46/53/+20/0.00/0.0/367/67          23 W   RMY N/A
12/13 54/44/49/+17/0.00/0.0/000/00          18 ESE RMY 19
12/14 60/43/52/+20/…./0.0/000/00          32 S   RMY N/A
12/15 61/45/53/+21/…./0.0/371/68          48 W   RMY 51
12/16 45/34/40/+9/0.00/0.0/415/76           25 N   RMY N/A
12/17 53/36/45/+14/…./0.0/000/00          29 SE  RMY 28
12/18 50/35/43/+12/…./0.0/000/00          29 NW  RMY 30
12/19 38/30/34/+4/0.00/0.0/…/..           39 W   RMY 40
12/20 40/28/34/+4/0.00/0.0/…/..           24 W   RMY N/A

12/21 low since midnight is 31F; normal low is now 22F

DAILY RECORDS FOR DECEMBER 2015

**12/13/2015- NEW DAILY RECORD HIGH MINIMUM TEMPERATURE OF 44F,
BREAKS PREVIOUS RECORD OF 43F SET IN 1919, TIED 1983**

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

RECORDS FOR DECEMBER 21
HIGH 60 IN 1957
LOW -10 IN 1942
PRECIP 2.01 INS. IN 1946
SNOWFALL 11.4 INS. IN 1954
PEAK GUST 77 MPH SSE IN 1957

RECORDS FOR DECEMBER 22
HIGH 62 IN 1994
LOW -5 IN 1921
PRECIP 1.52 INS. IN 1975
SNOWFALL 8.8 INS. IN 1975
PEAK GUST 62 MPH WNW IN 1998

TODAY’S REPORT PREPARED BY: Brian Fitzgerald