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

DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, FEBRUARY 19, 2018  
ALL TIMES ARE IN EASTERN STANDARD TIME

PRESSURE DROPS, CLOUDS INCREASE AND TEMPERATURES 
QUICKLY RISE AFTER A CLEAR SEASONABLE MORNING...

Pressure began dropping around 7:00 A.M. this 
morning, after this pressure drop we observed an 
increase in both cloud cover and wind speeds. The 
morning began clear and seasonable with an overnight 
low of 30F. This is only 1 degree above the daily 
normal of 29F. Wind shifted from WNW-S around 
2:00 A.M. This allowed for temperatures to quickly 
rise today with a high so far of 47F by 1:00 P.M. 
This is 9 degrees above the daily normal of 38F.
Visibility was obscured today to a max of 60 miles
due to a distant haze.   

Today's Observations:

7 A.M.
Weather: Clear, few cirrus in all directions
Temperature: 32F; Dew Point: 20F; Wind: S at 16G20 kts
Sea-level pressure: 30.56 ins. Hg, rising unsteadily      
Visibility:  55 miles, distant haze SSE-NNE
6-hr Max temp: 32F
6-hr Min temp: 30F
24-hr precip:  0.00 ins.
24-hr snowfall: 0.0 ins.
Snow depth: 3 ins.
BHO SA 1155 CLR 55 349/32/20/1816G20/056/ FEW CI ALQDS 
DSNT HZ SSE-NNE / 8/001 4/003 52013 10032 20030 

10 A.M.
Weather: Scattered cirrostratus, few cumulus E-S,
few cirrus ESE-SSW
Temperature: 40F; Dew Point: 29F; Wind: S at 17G26 kts,
Peak wind: 26 kts (30 MPH) S at 9:54 A.M.
Sea-level pressure: 30.53 ins. Hg, falling, then more quickly 
Visibility: 40 miles, distant haze SSE-NNE 
3-hr precip: 0.00
3-hr snowfall: 0.0 ins.  
BHO SA 1455 250 SCT 40 337/40/29/1917G26/053/ FEW CU E-S 
FEW CI ESE-SSW DSNT HZ SSE-NNE PK WND 2026/54/ 8/108 58012

1 P.M.
Weather: Scattered cumulus, scattered altocumulus,
broken cirrostratus 
Temperature: 46F; Dew Point: 37F; Wind: SSW at 20G33 kts,
Peak Wind: 33 kts (38 MPH) at 12:49 P.M 
Sea-level pressure: 30.43 Hg, falling, then more quickly   
Visibility: 60 miles, distant haze SSE-NNE   
6-hr Max temp: 47F
6-hr Min temp: 32F
6-hr precip: 0.00 ins.
6-hr snowfall: 0.0 ins.
Snow depth: 1 in.
BHO SA 1755 30 SCT 120 SCT E220 BKN 60 305/46/37/2120G33/043/ 
DSNT HZ SSE-NNE PK WND 2133/49/ 8/138 4/001 58032 10047 20032

SUMMARY FOR SUNDAY, FEBRUARY 18, 2018

TEMPERATURE (DEGREES F)
MAX.....41   NORMAL.....37
MIN.....29   NORMAL.....20
MEAN....35   NORMAL.....29

DEPARTURE FROM 30-YEAR NORMAL............................+6
TOTAL DEPARTURE FOR THE MONTH...........................+87 [+4.6 DEGREES/DAY]

HEATING DEGREE DAYS (SEASON JUL TO JUN)
TOTAL HEATING UNITS FOR YESTERDAY.............30   DEPARTURE..........-6
TOTAL HEATING UNITS FOR THE MONTH............596   DEPARTURE.........-88
TOTAL HEATING UNITS FOR THE SEASON..........3917   DEPARTURE........-298
TOTAL HEATING UNITS LAST SEASON TO DATE.....3684   DIFFERENCE.......+233

PEAK GUST AND AVERAGE WIND SPEED (MPH) 
PEAK WIND GUST FOR YESTERDAY....................33 WNW AT 10:13 A.M. 
                   AERO.........................29 WNW AT 11:18 A.M.* 
                   ASOS.........................33 NW  AT 11:18 A.M.
                   DAVIS........................30 M   AT 10:03 A.M.** RMY 34
FASTEST MILE FOR YESTERDAY......................23 WNW AT 11:03 A.M.   
MAXIMUM 2-MINUTE ASOS AVERAGE...................23 WNW AT 11:03 A.M.  
MAXIMUM 2-MINUTE DAVIS AVERAGE..................21 M   AT 11:03 A.M.**
AVERAGE WIND SPEED AND DIRECTION................10.4   NW
                   ASOS.........................10.5 
                   DAVIS.........................9.5 ** 
* Last of multiple occurrences
** Davis direction malfunctioning

PRECIPITATION (INCHES) THROUGH THIS MORNING (EST)
TOTAL PRECIPITATION 24 HRS ENDING 7 A.M....0.00  DEPARTURE......-0.15
                         ASOS..............0.00
TOTAL PRECIPITATION FOR THE MONTH..........3.15  DEPARTURE......+0.64
                         ASOS..............3.28  
TOTAL PRECIPITATION FOR THE YEAR...........9.15  DEPARTURE......+2.29
                         ASOS..............9.85

SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE........+0.0
TOTAL SNOWFALL FOR THE MONTH................9.4  DEPARTURE........+0.5
TOTAL SNOWFALL FOR THE SEASON..............43.9  DEPARTURE........+1.8

PRELIMINARY CLIMATE SUMMARY FOR FEBRUARY CALENDAR DAY DATA
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOW/SUN(MIN.)/SUN(%)/PEAK GUST/AERO/RMY GUST
AERO: Aerovane wind recording system 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
M:    Missing data

2/1  45/27/36/+10/..../0.0/120/20      36 SSW AERO 35 SSW RMY N/A 
2/2  34/08/21/-5/..../2.5/223/37       43 WNW AERO 46 WNW RMY 46 
2/3  25/04/15/-11/0.00/0.0/557/92      26 S   AERO 24 S   RMY 30 
2/4  45/23/34/+8/.../T/000/00          31 SSE AERO 29 S   RMY 30
2/5  46/19/33/+7/0.00/0.0/464/76       47 WNW AERO 47 WNW RMY 44
2/6  31/17/24/+2/T/T/025/04            26 SSW AERO 23 SSW RMY 23 
2/7  42/21/32/+5/0.62/1.1/000/00       45 SW  AERO 46 SW  RMY 47
2/8  30/20/25/-2/0.00/0.0/501/81       38 WNW AERO 38 WNW RMY N/A
2/9  30/16/23/-4/0.00/0.0/384/62       28 S   AERO 25 S   RMY N/A
2/10 51/28/40/+13/..../0.0/.../..      31 S   AERO 30 S   RMY 31
2/11 46/36/41/+14/..../0.0/000/00      24 SW  AERO 21 SW  RMY N/A
2/12 53/27/40/+13/..../0.0/.../..      33 WNW AERO 33 WNW RMY N/A
2/13 31/21/26/-2/0.00/0.0/.../..       22 S   AERO 18 WNW RMY 21
2/14 46/25/36/+8/0.00/0.0/.../..       30 S   AERO 26 SSW RMY 29 
2/15 47/35/41/+13/..../0.0/000/00      23 SSW AERO 20 SSW RMY N/A
2/16 50/31/41/+13/..../0.0/.../..      45 W   AERO 44 W   RMY 42
2/17 38/23/31/+3/..../.../.../..       33 SSW AERO 29 SSE RMY 33
2/18 42/29/35/+6/..../.../.../..       32 WNW AERO 29 WNW RMY 34 

2/19 Low temp since midnight is 30F; normal low is now 29F

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

RECORDS FOR FEBRUARY 19
HIGH 66F IN 1981
LOW -5F IN 1923
PRECIP 2.73 INCHES IN 1972
SNOWFALL 12.0 INCHES IN 1893
PEAK GUST 76 MPH ENE IN 1972

RECORDS FOR FEBRUARY 20
HIGH 66F IN 1930
LOW -4F IN 1966
PRECIP 1.90 INCHES IN 1934
SNOWFALL 15.0 INCHES IN 1921,1934
PEAK GUST 78 MPH NW IN 1972

TODAY'S REPORT PREPARED BY: Kaitlin Geagan