FPCN39 CWLW 141347
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 SUNDAY 14 SEPTEMBER 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   15     200   1     23   18    1100   2
KAMLOOPS     KEL      15   15     900   1     35   18    1350   3
OKANAGAN     KEL      14   15     900   1     35   18    1350   3
CASTLEGAR    SPOK     22   15     750   5     27   17     900   5
CRANBROOK    SPOK      9   12     950  20     10   17     950  20
REVELSTOKE   KEL      11   13     650   1     18   15    1050   2

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S   13   S   28   S   46
CRANBROOK             S   15   S   41

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1700 m         21 C
SPOKANE         2000 m         29 C

TODAY'S VENTING: poor to fair.

VENTING FOR MONDAY: good.

VENTING OUTLOOK TUESDAY THRU THURSDAY: generally 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.      9   10     950  13     50   13    1450  10
PR. GEORGE   P.G.     39   11    1000  11     54   15    1450  10
SMITHERS     P.G.     37   11     900   9     59   15    1200  10
WELLS GRAY   P.G.     42   11    1300  13     95   14    2450  11
FT NLSN      F.N.     41    7     600  16    100   12    1900  15
FT STJOHN    F.N.      9    5     700  16     80    8    1400  16

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   31   S   44
SMITHERS              E   20   E   44

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1500 m         19 C
FT. NELSON       800 m          9 C

TODAY'S VENTING: generally fair.

VENTING FOR MONDAY: good.

VENTING OUTLOOK TUESDAY THRU THURSDAY: becoming only fair.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     22   15     100  38    100   17     750  39
FRASER VLY   QUIL     72   16     300  38    100   19    1100  40
SRN VRISL    QUIL     16   15      50  12     86   17     550  25
CNTRL VRISL  QUIL      9   14      50  12     86   16     200  25
NRN VRISL    HRDY      9   12     150   0     86   15     350  22
TERRACE      ANT      10   14     250  13     95   18    1800  10
STEWART      ANT      14   14     100   7     59   18     700  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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   43   S   54   S   59
PORT HARDY   SW  13   W   15   NW  17
SANDSPIT     N   31   N   20   N   15

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      none
PORT HARDY      1100 m         23 C
ANNETTE          200 m         17 C

TODAY'S VENTING: becoming good.

VENTING FOR MONDAY: good.

VENTING OUTLOOK TUESDAY THRU THURSDAY: becoming fair.

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


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