16
THURSDAY, JANUARY 11, 1990
IT WAS A MUCH BRIGHTER DAY ON DECEMBER 28 BUT CLOUDY WEATHER RETURNED THE NEXT DAY FOLLOWING THE PASSAGE OF A WEAK COLD FRONT. LIGHT RAIN OCCURRED IN THE TWO MORNINGS THAT FOLLOWED AND HEAVIER RAIN SET IN DURING THE EVENING ON DECEMBER 30. RAINY AND COOL WEATHER THEN PERSISTED TILL THE END OF THE MONTH.
DURING THE MONTH OF DECEMBER, NO AIRCRAFT WAS DIVERTED DUE TO ADVERSE WEATHER. THE RED FIRE DANGER WARNING WAS IN EFFECT ON DECEMBER 1-4 AND 5. THE YELLOW FIRE DANGER WARNING WAS ISSUED FOR DECEMBER 6-9, 10 AND 14-17.
WEATHER SYSTEM
SIGNALS HOISTED DURING THE MONTH WERE AS FOLLOWS:
SIGNAL
DATE AND TIME
OF HOISTING
DATE AND TIME OF LOWERING
WINTER
MONSOON
STRONG MONSOON
DECEMBER 10 00.00 AM
DECEMBER 10 9 AM
WINTER
STRONG
MONSOON
MONSOON
DECEMBER 18 11 AM
DECEMBER 19
9 AM
WINTER
STRONG
MONSOON
MONSOON
DECEMBER 19 10.40 PM
DECEMBER 20
7 AM
THE MONTH'S FIGURES AND DEPARTURES FROM NORMAL WERE:
TOTAL BRIGHT SUNSHINE
164.1 HOURS ;
15.2 HOURS BELOW NORMAL
MEAN DAILY GLOBAL
SOLAR RADIATION
9.69 MJ/ SQUARE METRE
;
2.54 MJ/SQUARE METRE BELOW NORMAL.
TOTAL RAINFALL
40.2 MM
;
14.9 MM ABOVE NORMAL
MEAN AMOUNT OF CLOUD
45 PER CENT
;
7 PER CENT LESS THAN NORMAL
MEAN RELATIVE HUMIDITY
74 PER CENT
;
5 PER CENT HIGHER THAN NORMAL
MEAN DAILY MAXIMUM AIR TEMPERATURE
MEAN AIR TEMPERATURE
19.9 DEGREES CELSIUS
;
0.9 DEGREE CELSIUS BELOW NORMAL
17.8 DEGREES CELSIUS
;
0.1 DEGREE CELSIUS ABOVE NORMAL
MEAN DAILY MINIMUM AIR TEMPERATURE
MEAN DEW POINT
15.8 DEGREES CELSIUS
;
0.6 DEGREE CELSIUS ABOVE NORMAL
12.8 DEGREES CELSIUS
TOTAL EVAPORATION
69.0 MM
;
1.4 DEGREES CELSIUS ABOVE NORMAL
47.0 MM BELOW NORMAL
0
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