FPCN39 CWLW 101429
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 10 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      80   11     400  20    100   13    2000  16
KAMLOOPS     KEL      80   10    1800  20    100   14    2000  14
OKANAGAN     KEL      80   10    1400  20    100   13    1850  14
CASTLEGAR    SPOK     75    7    1200  15     74   12    1700   8
CRANBROOK    SPOK     49    5     900  10    100    9    2250  19
REVELSTOKE   KEL      43    8     100  10    100   11    1700  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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S    9   SW  20   SW  39
CRANBROOK             SW  13   SW  37

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         No inversion
SPOKANE         No inversion

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.     35    2     400   5    100    9    2350  14
PR. GEORGE   P.G.     54    1    1200   6     47    4    1200   9
SMITHERS     P.G.     30    1    1000   5     36    4    1100   5
WELLS GRAY   P.G.     50    5    1500  10    100    9    2450  14
FT NLSN      F.N.     42   -2    1100   5     48   -1    1300   5
FT STJOHN    F.N.      9   -5     700   8     50    2    1500   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  35   SW  44
SMITHERS              W   20   W   44

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1300 m          8 C
FT. NELSON      3000 m         17 C

TODAY'S VENTING: Fair to good.

VENTING FOR SATURDAY: Fair to good.

VENTING OUTLOOK SUNDAY THRU TUESDAY: Fair to good.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     73   10    1000  18    100   14    1600  15
FRASER VLY   QUIL     64   10    1000  15    100   14    1500  15
SRN VRISL    QUIL     45   10     800  15     97   14    1350  12
CNTRL VRISL  QUIL     55    8     900  10     99   14    1400  12
NRN VRISL    HRDY     75   10     900  15     82   12     950  13
TERRACE      ANT       9    0     315   5     66    7    1350   7
STEWART      ANT       9    2     100   5     32    7     350   8

*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    SW  24   SW  28   SW  31
PORT HARDY   NW  33   NW  44   NW  54
SANDSPIT     W   31   NW  43   NW  54

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       200 m         12 C
PORT HARDY        No inversion
ANNETTE           No inversion

TODAY'S VENTING: Good.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: Fair to good.

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


END/DB