FPCN39 CWLW 241404
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 WEDNESDAY 24 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       9    0     300   0     43    4    1400   5
KAMLOOPS     KEL       9   -1     400   0     36    1     600   5
OKANAGAN     KEL       9    0     450   0     38    3     750   0
CASTLEGAR    SPOK      9   -1     750   5     38    1    1150   5
CRANBROOK    SPOK      9   -8    1050   2     24   -2    1150   5
REVELSTOKE   KEL       9   -1     450   0     21    1     550   0

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   NW  13   N   33
CRANBROOK             NW  13   NW  35

TODAY'S VENTING: FAIR

VENTING FOR THURSDAY: POOR


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   -5    1050   2     24   -1    1150   8
PR. GEORGE   P.G.      9   -1     700   5     33    1     950  10
SMITHERS     P.G.     23   -1     750   6     36    2     900   8
WELLS GRAY   P.G.      9   -4    1000   8     47    0    1400   8
FT NLSN      F.N.      9  -13     550   8     21   -8     550   8
FT STJOHN    F.N.     21    1    1050  20     60    3    1400  20

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   59   W   74
SMITHERS              W   63   W   74

TODAY'S VENTING: POOR EXCEPT GOOD BC PEACE.

VENTING FOR THURSDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9    4     100   5     24    6     300   7
FRASER VLY   QUIL      9    4     100   5     18    5     250   5
SRN VRISL    QUIL      9    5     200   0     23    7     350   4
CNTRL VRISL  QUIL      9    3     150   0     21    4     300   4
NRN VRISL    HRDY      9    4       0   6     29    6     350   6
TERRACE      ANT      10    3     250   5     23    4     350   6
STEWART      ANT       9    3     100   5     21    4     250   6

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   NW  22   N   37
PORT HARDY   W   17   W   24   NW  41
SANDSPIT     W   43   W   43   W   54

TODAY'S VENTING: POOR

VENTING FOR THURSDAY: POOR

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


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