FPCN39 CWLW 221457
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 MONDAY 22 DECEMBER 1997 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      40    2    1100   4     75    4    1550   20
KAMLOOPS     KEL      19   -2     650   4     50    0    1000   10
OKANAGAN     KEL      11   -5     500   1     45   -1     700   7
CASTLEGAR    SPOK     28   -4     800   7     33    0     850   7
CRANBROOK    SPOK      9   -7     950   8      9   -4     950   8
REVELSTOKE   KEL      10   -5     550   1     17   -2     650   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S   11   SW  28   W   57
CRANBROOK             W   17   W   57

TODAY'S VENTING: POOR EXCEPT GOOD IN THE FRASER CANYON.


VENTING FOR TUESDAY: 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.     82   -4    1200  43     97   -2    1300  43
PR. GEORGE   P.G.     89   -3    1150  31    100   -1    1250  35
SMITHERS     P.G.     99   -1    1150  27    100    0    1200  27
WELLS GRAY   P.G.     86   -3    1300  43    100   -1    1600  41
FT NLSN      F.N.     17  -16     500   6     19  -14     550   6
FT STJOHN    F.N.     23   -1     800  14     63    2    1200  14

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  72   W   98
SMITHERS              SW  57   SW  98

TODAY'S VENTING: GOOD EXCEPT POOR IN THE FORT NELSON AREA.


VENTING FOR TUESDAY: FAIR.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     32    5     200  20     57    7     400  20
FRASER VLY   QUIL      9    4      50  20     58    7     350  20
SRN VRISL    QUIL     20    6     250   5     44    7     350  10
CNTRL VRISL  QUIL     13    4     100   5     43    4     100  10
NRN VRISL    HRDY     77    5     350  30    100    6     600  30
TERRACE      ANT       9    0     200  30    100    1    2000  30
STEWART      ANT       9    2       0  26    100    1    2000  26

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   61   SW  80   SW  80
PORT HARDY   W   48   W   57   SW  72
SANDSPIT     SW  78   W   80   W   76

TODAY'S VENTING: GOOD


VENTING FOR TUESDAY: GOOD.


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


END/GF