BLUE HILL METEOROLOGICAL OBSERVATORY
MILTON, MASSACHUSETTS 02186
ELEVATION 635 FEET, 10 MILES SSW OF BOSTON, MA
 
DAILY DISCUSSION AND CLIMATE SUMMARY
MONDAY, MARCH 5, 2007  
ALL TIMES ARE IN EASTERN STANDARD TIME
 
BITTERLY COLD ARCTIC AIRMASS LIKELY TO KNOCK  
TEMPERATURES DOWN CLOSE TO EARLY MARCH RECORDS
 
Even though it's now March the latest in the long 
series of Arctic air outbreaks continues and this  
latest one arriving later today could be close to 
the coldest of the season.
 
The low temperature for February was not unusually cold
for that month at 5 degrees on the 5th and 19th.  The 
lowest for the entire season is 1 below zero on January 26 
and December's low was a relatively balmy 17 degrees!
 
Below are our coldest daily readings for the next few days:
 
March 6:
Record low minimum: 3 deg. above zero in 1948. 
Record low maximum: 21 deg. in 1916 
 
March 7:
Record low minimum: 1 deg. below zero in 1890.
Record low maximum: 14 deg. in 1920
 
March 8: 
Record low minimum: 2 above zero in 1986
Record low maximum: 21 in 1989.
 
The lowest minimum temperature for March is 5 deg. below zero 
on March 4, 1950.  Low temperatures have reached zero or below
on nine dates in March the latest of which was 2 below zero on 
March 29, 1923. The lowest maximim temperature for the month is 
9 degrees on March 1, 1886.
 
Today's observations:
 
7 A.M.   
Weather: High dense cirrus overcast, few breaks
Temperature: 27F, Dew point: 16F, Wind: SW at 11 kts 
Sea-level pressure: 29.68 inches Hg, rising
Visibility: 55 miles 
6-hour min. temp. 25 deg. 
Snow depth: trace
BHO SA 1155 E200 OVC 55 052/27/16/2211/968/ SC/CUFRM TOPS 
DSNT NE-S-SSW AC/ACSL SSW-NW-NE DENSE CI ALQDS BINOVC SSW-WNW
AND DSNT E-ESE/ 8/542 55002 10027 20025

10 A.M.   
Weather: Scattered stratocumulus, middle dense overcast altostratus 
Temperature: 27F, Dew point: 16F, Wind: SW at 11 kts 
Sea-level pressure: 29.68 inches Hg, rising
Visibility: 40 miles, 30 miles west, flurries, 50 miles NE-SE  
BHO SA 1455 40 SCT 80 SCT E160 OVC 35 039/31/14/2314G23/965/ 
FEW THN SPTS IOVC OVHD SUN DMLY VSB VIRGA DSNT W VSBY W 35 
LWRG NE-SE 50 PK WND 2326/34/ WND 21V27/ 8/51/ 58013
 
1 P.M.   
Weather: Overcast variable broken stratocumuls, cumulus
Temperature: 34F, Dew point: 15F, Wind: SW at 17G28 kts 
Peak wind: WSW @ 32 kts @ 05 past the hour
Sea-level pressure: 29.57 inches Hg, falling
Visibility: 50 miles 
6-hour max. temp. 34 deg.
BHO SA 1755 50 SCT E55V OVC 50 013/34/15/2217G28/957/ CU/SC MDT CU 
55 OVC V BKN VIRGA ALQDS PK WND 2432/05/ WND 19V26/ 
8/200 58026 10035 20027
 
   
WEATHER SUMMARY FOR SUNDAY, MARCH 4
 
TEMPERATURE (DEGREES F)
MAX.....40    NORMAL.....41 
MIN.....26    NORMAL.....24
MEAN....33    NORMAL.....33                     
 
DEPARTURE FROM 30-YEAR NORMAL...........0
TOTAL DEPARTURE FOR THE MONTH.........+20 (+4.8 DEGREES/DAY) 
 
HEATING DEGREE DAYS
TOTAL HEATING UNITS FOR YESTERDAY..........32   DEPARTURE.......- 1
TOTAL HEATING UNITS FOR THE MONTH.........111   DEPARTURE.......-22 
TOTAL HEATING UNITS FOR THE SEASON.......4202   DEPARTURE......-501
TOTAL HEATING UNITS LAST SEASON TO DATE..4256   DIFFERENCE......-54
 
PEAK GUST AND AVERAGE WIND SPEED (MPH)
PEAK WIND GUST FOR YESTERDAY............37   W  AT 7:59 P.M. *      
                   AEROVANE.............34   W  AT 7:59 P.M. *      
                   ASOS.................33   W  AT 7:59 P.M.        
                   DAVIS................35   W  AT 2:13 P.M.        
FASTEST MILE FOR YESTERDAY..............28   W  AT 9:05 P.M.      
MAXIMUM 2-MINUTE ASOS AVERAGE...........28   W  AT 9:06 P.M.  
MAXIMUM 1-MINUTE DAVIS AVERAGE..........30   W  AT 9:05 P.M. 
AVERAGE WIND SPEED AND DIRECTION......17.3   W  
                    ASOS..............16.9      
                    DAVIS.............17.8   W [260 deg] 
* last of several occurrences...
 
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..........1.74  DEPARTURE....+0.99  
                         ASOS..............1.75    
TOTAL PRECIPITATION FOR THE YEAR...........7.46  DEPARTURE....-2.13  
                         ASOS..............7.38
 
SNOWFALL (INCHES) THROUGH THIS MORNING (EST)
TOTAL SNOWFALL 24 HRS ENDING 7 A.M..........0.0  DEPARTURE......-0.5
TOTAL SNOWFALL FOR THE MONTH................0.4  DEPARTURE......-1.6  
TOTAL SNOWFALL FOR THE SEASON..............14.3  DEPARTURE.....-33.1 
 
    
PRELIMINARY CLIMATE SUMMARY FOR MARCH 2007......CALENDAR DAY DATA
DATA REPORTED:
DATE: MAX/MIN/MEAN/DEP/PRECIP/SNOWFALL/SUN(MIN.)/SUN(%)/ PEAK GUST/AERO GUST
 
AERO: Aerovane recording wind system when significant
TSTM: Thunderstorm day
....: Data not yet available
 
3/1  40/22/31/-1/0/0/512/76          24 NW   Aero 23 MPH NW
3/2  49/28/39/+7/1.74/0.4/000/00     48 E    Aero 45 MPH E
3/3  58/33/46/+14/0/0/489/72         44 WNW  Aero 43 MPH WNW
3/4  40/26/33/0/0/0/471/69           37 W
 
3/5  morning low temp. 25 deg; normal now is also 25 deg. 
   
DAILY EXTREMES
Temperature and precipitation records back to 1885, and
wind records back to 1940 (e = estimated):
 
RECORDS FOR MARCH 5
HIGH 64 IN 1979
LOW  -2 IN 1948
PRECIP 1.76 INCHES IN 2001
SNOWFALL 13.0 INCHES IN 1891
PEAK GUST 76e MPH WNW IN 1971
 
RECORDS FOR MARCH 6
HIGH 66 IN 1894
LOW 3 IN 1948
PRECIP 1.85 INS. IN 2001
SNOWFALL 15.5 INS. IN 2001
PEAK GUST 82 MPH S IN 1959
 
TODAY'S REPORT By: Robert Skilling