FPCN39 CWLW 051429
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 7:00 AM PST SATURDAY 5 DECEMBER 1998 FOR TODAY.

VENTILATION INDICES (TEMPERATURE) AND MIXING HEIGHTS.
MIXING HEIGHTS IN METRES ABOVE SEA LEVEL.
AVERAGE WINDS IN KNOTS.

SPOT INDICES ARE DETERMINED BY THE ASPECT AND ELEVATION OF THE SITES.
COMPARE WINDS, TEMPERATURES AND ELEVATION WITH THE SITES HERE
TO DETERMINE THE INDEX IN ANY OTHER AREA.

SOUTHERN INTERIOR

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
FRSR CANYN   KEL       9    0     200   4     65    2    1300   6
KAMLOOPS     KEL      15    0     500   4     65    2    1300   8
OKANAGAN     KEL      15    0     500   4     65    2    1300   8
CASTLEGAR    SPOK     63    0    1150  11     76    2    1350  12
CRANBROOK    SPOK      9   -7     950  14     64   -3    1650  14
REVELSTOKE   KEL      14    0     550   4     44    0     850   4


*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S   11   S   30   S   70
CRANBROOK             SW  22   SW  63

TODAY'S VENTING: GENERALLY GOOD.


VENTING FOR SUNDAY: FAIR.


CENTRAL INTERIOR/NORTHEAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
WILLIAMS L   P.G.      9   -3     950  15     60   -2    1200  15
PR. GEORGE   P.G.     10   -1     700   8     40   -1     900   8
SMITHERS     P.G.     24    0     700   8     75    0    1800   8
WELLS GRAY   P.G.     25   -3     900  10     60   -2    1200  15
FT NLSN      F.N.     11  -21     500   2     13  -16     600   2
FT STJOHN    F.N.     10  -14     700   9     10  -10     700   9


*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   33   S   20
SMITHERS              W   30   NW  20

TODAY'S VENTING: FAIR TO POOR EXCEPT GOOD IN THE NORTHWEST WHERE
AN UNSTABLE AIRMASS WILL MOVE OVER THE AREA IN THE WAKE OF A FRONTAL
SYSTEM.



VENTING FOR SUNDAY: FAIR



COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     83    6     500  29    100    7     750  33
FRASER VLY   QUIL     80    6     450  29     80    6     450  29
SRN VRISL    QUIL     87    7     600  23    100    8     850  31
CNTRL VRISL  QUIL     65    6     350  23     96    7     600  28
NRN VRISL    HRDY     42    5     250  18    100    8    1050  24
TERRACE      ANT      40    0     200  12     90    2    1400  12
STEWART      ANT      40   -1     200  12     90    2    1400   4



*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  20   SW  26   W   20
PORT HARDY   NW  52   NW  63   NW  61
SANDSPIT     NW  44   NW  52   NW  50

TODAY'S VENTING: GOOD.


VENTING FOR SUNDAY: FAIR.


VENTILATION GUIDELINES:
          0-33.....POOR
          34-54.....FAIR
          55-100.....GOOD.
VENTILATION INDICES NORMALLY DROP TO POOR AFTER SUNSET.


END/GF