Friday, November 15, 2013

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

DAILY DISCUSSION AND CLIMATE SUMMARY
FRIDAY, NOVEMBER 15, 2013
ALL TIMES ARE IN EASTERN STANDARD TIME

STRONG TEMPERATURE INVERSION THIS MORNING;
TEMPERATURES MODERATING NICELY WITH VERY DRY AIR MASS

A strong temperature inversion was quite apparent by taking a look at
morning lows this morning: Blue Hill 38F, Hingham 28F, Plymouth 26F, and
nearby Norwood 21F. It was cold enough in the lower elevations for a thin
layer of ice to form and cover about 10-20% of Ponkapoag Pond. Some
impressive looming of the distant mountains also occurred this morning
with the temperature inversion, making the mountains look much larger than
reality.

Temperatures have warmed up nicely this afternoon, nearing 60F here on the
summit. Today is a solid 10 degrees warmer than yesterday, and will likely
finish several degrees above normal for the date.

The air mass is very dry despite persistent SW winds today. Dew point
temperatures have been down in the teens to near 20F, producing very low
relative humidity this afternoon of 20-25%.

Today’s Observations:

7 A.M.
Weather: Scattered altocumulus, broken thin cirrus, few cirrocumulus,
inversion present, small smoke plume distant S drifting ENE, thin smoke
layer distant all quadrants, distant haze
Temperature: 40F; Dew Point: 15F; Wind: SW at 12 kts.
Sea-level pressure: 30.20 ins. Hg, rising then rising more quickly
Visibility: 65 miles, distant haze
6-hr min temp: 38F
BHO SA 1155 140 SCT 250 –BKN 65 228/40/15/2212/020/ FEW CC INVSN PRSNT
SML K PLUME DSNT S DRFTNG ENE THN K LYR DSNT ALQDS DSNT HZ/ 8/049 51014
10040 20038

10 A.M.
Weather: Scattered altocumulus, scattered cirrostratus, broken thin cirrus,
cirrostratus invading, few cirrocumulus mostly WNW-NNE, inversion present,
small smoke plume distant S, smoke layer along/above horizon all quadrants,
hazy
Temperature: 49F; Dew Point: 20F; Wind: SW at 6 kts.
Sea-level pressure: 30.22 ins. Hg, rising slightly then steady
Visibility: 65 miles, hazy, smoke layer along/above horizon all quadrants
BHO SA 1455 140 SCT 200 SCT 250 –BKN 233/49/20/2206/022/ CS INVADING FEW
CC MSTLY WNW-NNE INVSN PRSNT SML K PLUME DSNT S K LYR ALG/ABV HRZN ALQDS
HAZY/ 8/049 52005

1 P.M.
Weather: Scattered cirrostratus, scattered dense cirrus, broken thin
cirrus, few altocumulus all quadrants, few cirrocumulus all quadrants and
overhead, parahelion, thin smoke layer distant W-N-ESE, dark smoke layer
distant NNE-ENE, hazy
Temperature: 57F; Dew Point: 21F; Wind: SSW at 12 kts,
Wind: Direction variable S-SW
Sea-level pressure: 30.16 ins. Hg, falling then falling more rapidly
Visibility: 65 miles, hazy
6-hr max temp: 59F
BHO SA 1755 200 SCT 220 SCT 250 –BKN 65 215/57/21/2012/016/ FEW AC ALQDS
FEW CC ALQDS AND OVHD PARHELION THN K LYR DSNT W-N-ESE DRK K LYR DSNT
NNE-ENE HAZY WND 17V23/ 8/049 58018 10059 20040

WEATHER SUMMARY FOR THURSDAY, NOVEMBER 14, 2013

TEMPERATURE (DEGREES F)
MAX…..49 NORMAL…..51
MIN…..26 NORMAL…..34
MEAN….38 NORMAL…..42

DEPARTURE FROM 30-YEAR NORMAL………………….-4
TOTAL DEPARTURE FOR THE MONTH…………………-17 [-1.4 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY…………..27 DEPARTURE………+4
TOTAL HEATING UNITS FOR THE MONTH………….311 DEPARTURE……..+22
TOTAL HEATING UNITS FOR THE SEASON…………788 DEPARTURE……..-64
TOTAL HEATING UNITS LAST SEASON TO DATE…….710 DIFFERENCE…….+78

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY………………25 W AT 11:31 A.M.
AERO…………………..25 W AT 11:31 A.M.
ASOS…………………..27 WSW AT 11:22 A.M.
DAVIS………………….26 WSW AT 11:22 A.M. RMY 28
FASTEST MILE FOR YESTERDAY………………..20 W AT 11:31 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE……………..21 W AT 11:32 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE…………….18 WSW AT 11:22 A.M.
AVERAGE WIND SPEED AND DIRECTION…………14.3 SW
ASOS…………………13.8
DAVIS………………..13.0 SW [232 degrees]

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……….0.66 DEPARTURE…………-1.54
ASOS…………..0.64
TOTAL PRECIPITATION FOR THE YEAR……….43.61 DEPARTURE…………-2.30
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…………..0.0
TOTAL SNOWFALL FOR THE MONTH………….0.2 DEPARTURE………….-0.3
TOTAL SNOWFALL FOR THE SEASON…………0.2 DEPARTURE………….-0.6

PRELIMINARY CLIMATE SUMMARY FOR NOVEMBER 2013 CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/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

11/1 68/56/62/+16/0.10/0.0/012/02 60 SSW AERO N/A N/A RMY 66
11/2 65/49/57/+11/0.00/0.0/296/48 22 WSW AERO N/A N/A RMY 23
11/3 49/30/40/-6/0.06/T/135/22 23 N AERO N/A N/A RMY N/A
11/4 42/27/35/-10/0.00/0.0/588/96 24 NNE AERO N/A N/A RMY 25
11/5 50/29/40/-5/0.00/0.0/487/80 16 SSW AERO N/A N/A RMY 17
11/6 59/40/50/+5/0.00/0.0/419/69 30 SSW AERO 31 MPH SSW RMY 33
11/7 65/37/51/+6/0.31/0.0/079/13 33 SW AERO 37 MPH SW RMY 37
11/8 48/31/40/-4/T/T/0.0/421/70 37 WNW AERO 37 MPH WNW RMY 39
11/9 44/29/37/-7/0.00/0.0/366/61 25 WNW AERO 25 MPH WNW RMY 29
11/10 52/40/46/+2/0.08/0.0/108/18 31 WNW AERO 33 MPH WNW RMY N/A
11/11 51/36/44/+1/0.00/0.0/…/.. 36 WNW AERO 37 MPH WNW RMY 37
11/12 48/24/36/-7/0.11/0.2/000/00 42 SW AERO 43 MPH SW RMY 43
11/13 35/21/28/-15/0.00/0.0/…/.. 29 NW AERO 30 MPH NW RMY 30
11/14 49/26/38/-4/0.00/0.0/…/.. 25 SW AERO 25 MPH SW RMY 28

11/15 morning low temp: 38F; the normal low is now 34F

DAILY RECORDS FOR NOVEMBER 2013
None so far.

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

RECORDS FOR NOVEMBER 15
HIGH 74 IN 1993
LOW 15 IN 1933
PRECIP 1.66 INCHES IN 1981
SNOWFALL 4.0 IN 1967
PEAK GUST 65 SSE IN 2008

RECORDS FOR NOVEMBER 16
HIGH 73 IN 1927
LOW 8 IN 1933
PRECIP 2.25 INCHES IN 1981
SNOWFALL 2.0 IN 1913
PEAK GUST 78 S IN 1989

TODAY’S REPORT PREPARED BY: Sean Fankhauser