Wednesday, July 29, 2015

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

DAILY DISCUSSION AND CLIMATE SUMMARY
WEDNESDAY, JULY 29, 2015
ALL TIMES ARE IN EASTERN STANDARD TIME

THUNDERSTORMS AVOID THE SUMMIT ONCE MORE,
NEAR RECORD HEAT EXPECTED TODAY

Temperatures spiked yesterday afternoon to hit 89F
on two separate occasions, while towering and
moderate cumulus quickly formed a thunderstorm that
developed SSW of the station.

Temperatures have been off to the races this morning
after an overnight low of 70F. 90F was reached by the
10:00 AM EST observation with dew points in the mid to
upper 60s. Hazy conditions have left visibility reduced
to 20 miles in all directions.

By the 1:00 PM EST observation hazy conditions had
diminished visibility further to 15 miles in all directions.
Temperatures had been hovering at or around the 90F degree
mark with a maximum temperature reading of 91F so far.
Today’s Observations:

7 A.M.
Weather: Clear, altocumulus castellanus distant NNE,
few altocumulus distant W and NNE-E, few cirrus distant SSE-NW
Temperature: 77F; Dew Point: 67F; Wind: estimated NW at 4 kts
Wind Speed: Light
Sea-level pressure: 29.98 ins. Hg, rising, then more slowly
Visibility: 20 miles, hazy
6-hr Max temp: 77F
6-hr Min temp: 70F
24-hr precip: 0.00
BHO SA 1155 CLR 20 154/77/67/E3104/998/
ACC DSNT NNE FEW AC DSNT W AND NNE-E FEW CI DSNT SSE-NW HAZY WND LGT/
8/081 51007 10077 20070

10 A.M.
Weather: Thin broken cirrus, few cumulus SSW-N
Temperature: 90F; Dew Point 66F; Wind: Calm
Sea-level pressure: 29.98 ins. Hg, the same as 3 hours ago
Visibility: 20 miles, hazy
BHO SA 1455 E250 -BKN 20 154/90/66/0000/998/
FEW CU SSW-N HAZY WND CLM/ 8/101 50000

1 P.M.
Weather: Scattered cumulus, thin broken cirrus
Temperature: 90F; Dew Point: 66F; Wind: W at 8 kts,
Sea-level pressure: 29.94 ins. Hg, falling, then more slowly
Visibility: 15 miles, hazy
6-hr Max temp: 91F
6-hr Min temp: 77F
BHO SA 1755 60 SCT E250 -BKN 15 140/90/66/2708/994/ HAZY/
8/101 56014 10091 20077
SUMMARY FOR TUESDAY, JULY 28, 2015

TEMPERATURE (DEGREES F)
MAX…..89   NORMAL…..81
MIN…..68   NORMAL…..63
MEAN….79   NORMAL…..72

DEPARTURE FROM 30-YEAR NORMAL……………………+7
TOTAL DEPARTURE FOR THE MONTH…………………..+23 [+0.6 DEGREES/DAY]

COOLING DEGREE DAYS (SEASON JAN TO DEC)
TOTAL COOLING UNITS FOR YESTERDAY…………..14   DEPARTURE……….+6
TOTAL COOLING UNITS FOR THE MONTH………….211   DEPARTURE………+11
TOTAL COOLING UNITS FOR THE SEASON…………349   DEPARTURE………+20
TOTAL COOLING UNITS LAST SEASON TO DATE…….323   DIFFERENCE……..+26

PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY……………….18  S   AT 12:07 A.M.
ASOS……………………18  SSW AT 12:06 A.M.
DAVIS…………………..17  S   AT 12:06 A.M. RMY N/A
FASTEST MILE FOR YESTERDAY…………………13  S   AT 12:04 A.M.
MAXIMUM 2-MINUTE ASOS AVERAGE………………15  SSW AT 12:08 A.M.
MAXIMUM 2-MINUTE DAVIS AVERAGE……………..13  S   AT 12:08 A.M.
AVERAGE WIND SPEED AND DIRECTION……………7.0 S
ASOS……………………7.5
DAVIS…………………..6.4 SSW [202 deg.] * 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………..2.99  DEPARTURE…..-0.57
ASOS……………3.01
TOTAL PRECIPITATION FOR THE YEAR………..27.26  DEPARTURE…..-3.27
ASOS……………N/A ***
*** ASOS annual total not available due to erroneous readings
PRELIMINARY CLIMATE SUMMARY FOR JULY 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

7/1  80/63/72/+2/0.59/466/51               30 SSE RMY 33  TSTM
7/2  78/60/69/-1/0.00/721/79               23 WNW RMY N/A
7/3  79/58/69/-2/0.00/867/95               17 SSW RMY 17
7/4  74/61/68/-3/T/109/12                  16 S   RMY N/A
7/5  82/58/70/-1/0.00/865/95               20 WSW RMY 20
7/6  85/64/75/+4/0.00/755/83               20 S   RMY 21
7/7  84/65/75/+4/0.02/445/49               35 S   RMY 40
7/8  87/68/78/+6/T/372/41                  23 NE  RMY N/A
7/9  73/61/67/-5/…./390/43               24 NE  RMY 25
7/10 80/59/70/-2/…./535/59               18 W   RMY N/A TSTM
7/11 84/61/73/+1/0.00/868/96               21 NW  RMY 19
7/12 88/67/78/+6/0.00/813/90               20 W   RMY 17
7/13 82/66/74/+2/0.00/424/47               21 E   RMY 20
7/14 81/64/73/+1/…./396/44               25 S   RMY 27
7/15 84/61/73/+1/…./…/..               24 ENE RMY 26
7/16 72/56/64/-8/0.00/…/..               25 NNE RMY 24
7/17 79/56/68/-4/0.00/…/..               21 S   RMY N/A
7/18 76/63/70/-2/0.16/…/..               29 SSW RMY 30  TSTM
7/19 89/68/79/+7/0.01/…/..               25 SSW RMY 27
7/20 90/73/82/+10/0.00/…/..              24 W   RMY 26
7/21 87/70/79/+7/T/…/..                  24 W   RMY 25
7/22 82/64/73/+1/T/…/..                  24 WNW RMY 26
7/23 81/62/72/+0/0.00/…/..               22 W   RMY 23
7/24 80/60/70/-2/T/…/..                  23 N   RMY 25
7/25 71/59/65/-7/0.00/…/..               20 ENE RMY N/A
7/26 78/59/69/-3/T/…/..                  24 SSE RMY 25  TSTM
7/27 84/67/76/+4/T/…/..                  24 S   RMY N/A TSTM
7/28 89/68/79/+7/0.00/…/..               18 S   RMY N/A

7/29 low since midnight is 70F; normal low is now 63F

DAILY RECORDS FOR JULY 2015

7/10- NEW RECORD DAILY PRECIPITATION PENDING OF X.XX in 2015
surpasses previous record of 1.68 in. in 1933

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

RECORDS FOR JULY 29
HIGH 97F IN 1949
LOW 53F IN 1888,1914
PRECIP 1.53 INS IN 1901
PEAK GUST 40e MPH E IN 1941

RECORDS FOR JULY 30
HIGH 99F IN 1949
LOW 51F IN 1956
PRECIP 1.84 INS IN 1976
PEAK GUST 70e MPH SW 1944

TODAY’S REPORT PREPARED BY: Brian Fitzgerald