FPCN39 CWLW 171433
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 17 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      35   15     650  10     59   20    1250   6
KAMLOOPS     KEL      23   14     700   5     49   18    1200   6
OKANAGAN     KEL      17   12     600   3     54   19    1300   6
CASTLEGAR    SPOK     22   10     800   4     26   15     950   4
CRANBROOK    SPOK      9   10     495   5     15   15     950   5
REVELSTOKE   KEL      14   11     600  12     18   12     650   5

*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   W   19   W   28
CRANBROOK             W   13   W   37

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1600 m         22 C
SPOKANE         1000 m         16 C

TODAY'S VENTING: Poor.

VENTING FOR SATURDAY: Poor.

VENTING OUTLOOK SUNDAY THRU TUESDAY: 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.    100    9    2500  13    100   14    3950  15
PR. GEORGE   P.G.     32    8    1000   8    100   12    2650  12
SMITHERS     P.G.     10    4     600   1     80   11    2300  10
WELLS GRAY   P.G.    100    9    2650  13    100   13    4000  15
FT NLSN      F.N.     19   -2     900   2     20    0     950   2
FT STJOHN    F.N.     49    7    1450   7    100   12    3700  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
PR. GEORGE            W   26   NW  31
SMITHERS              W   22   W   31

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1150 m         11 C
FT. NELSON      1400 m         10 C

TODAY'S VENTING: Good.

VENTING FOR SATURDAY: Poor.

VENTING OUTLOOK SUNDAY THRU TUESDAY: Poor.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     51   13     350  18    100   15    1000  19
FRASER VLY   QUIL     41   13     250  18    100   15    1000  19
SRN VRISL    QUIL     24   14     550   3     94   16    1050  15
CNTRL VRISL  QUIL      9   11      50   3     70   14    1000  10
NRN VRISL    HRDY      9   10       0   9     43   12     450  10
TERRACE      ANT      10    8     250  13    100   10    1550  15
STEWART      ANT       9    9      50   0     28   10     350   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
VANCOUVER    W   19   W   20   W   31
PORT HARDY   NW  28   NW  35   NW  35
SANDSPIT     W   28   W   31   W   33

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      No inversion
PORT HARDY       100 m         11 C
ANNETTE          100 m         10 C

TODAY'S VENTING: Good..

VENTING FOR SATURDAY: Poor..

VENTING OUTLOOK SUNDAY THRU TUESDAY: Poor.

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


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