FPCN39 CWLW 241345
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 PDT FRIDAY 24 OCTOBER 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      13    7     500   1     76   12    2250   5
KAMLOOPS     KEL      11    6     550   1     82   12    2450   5
OKANAGAN     KEL      11    5     500   1     61   10    2050   4
CASTLEGAR    SPOK     39    5    1000   7     72   11    1800   7
CRANBROOK    SPOK      9    2     939   1     55    8    2100   5
REVELSTOKE   KEL       9    3     443   5     59    9    2050   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          600 m          6 C
SPOKANE         1200 m          9 C

TODAY'S VENTING: Good.

VENTING FOR SATURDAY: Good.

VENTING OUTLOOK SUNDAY THRU TUESDAY: Good.

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    0     950   3     33    5    1950   3
PR. GEORGE   P.G.     12    0     850   2     18    5    1150   2
SMITHERS     P.G.     13    3     850   1     14    5     950   1
WELLS GRAY   P.G.     14    2    1150   3     59    6    2700   4
FT NLSN      F.N.     31    0     550  15     44    3     650  15
FT STJOHN    F.N.      9    0     700  13     29    3     850  13

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   33   SW  37
SMITHERS              S   54   SW  37

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       600 m          5 C
FT. NELSON      1000 m         10 C

TODAY'S VENTING: Poor to fair.

VENTING FOR SATURDAY: Good.

VENTING OUTLOOK SUNDAY THRU TUESDAY: Good.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     16    7     200   8     51   11     650   9
FRASER VLY   QUIL     16    6     150   8     62   12     850   9
SRN VRISL    QUIL     20    9     200   6     61   13     900   8
CNTRL VRISL  QUIL     14    7     150   4     55   12     750   8
NRN VRISL    HRDY     29    8     200  11     65   11     550  14
TERRACE      ANT       9    6     200  17     55    8     550  17
STEWART      ANT       9    6       0  10      9    8       0  10

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   VR   5   W   13
PORT HARDY   S   54   S   46   SW  43
SANDSPIT     SW  83   SW  78   SW  80

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       250 m         11 C
PORT HARDY       700 m         15 C
ANNETTE             No inversion

TODAY'S VENTING: Good.

VENTING FOR SATURDAY: Good.

VENTING OUTLOOK SUNDAY THRU TUESDAY: Good.

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


END/DB