FPCN39 CWLW 231413
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 TUESDAY 23 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      17   18     600   2     54   27    1350   5
KAMLOOPS     KEL      16   17     600   3     26   25    1300   4
OKANAGAN     KEL      13   15     550   2     26   24    1050   4
CASTLEGAR    SPOK      9   16     800   0     19   23    1000   2
CRANBROOK    SPOK      9   14     950   5     35   23    1500   5
REVELSTOKE   KEL      12   15     600   2     23   20     850   3

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

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   S    9   S   17
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         2000 m         32 C
SPOKANE         2800 m         34 C

TODAY'S VENTING: POOR TO FAIR.

VENTING FOR WEDNESDAY: POOR TO FAIR.

VENTING OUTLOOK THURSDAY THRU SATURDAY: POOR TO FAIR BECOMING
GOOD SATURDAY.




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   17     950   6     50   25    1550  10
PR. GEORGE   P.G.     14   16     850   4     50   24    1500  10
SMITHERS     P.G.      9   13     700   0     54   18    1650   7
WELLS GRAY   P.G.      9   16    1000   6     60   25    1700  14
FT NLSN      F.N.      9    6     450   8     59   19    1400  15
FT STJOHN    F.N.     67   10     700  18     79   21    1450  17

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

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  28   SW  44
SMITHERS              SW  41   SW  44

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1000 m         21 C
FT. NELSON       800 m         21 C

TODAY'S VENTING: FAIR TO GOOD.

VENTING FOR WEDNESDAY: FAIR.

VENTING OUTLOOK THURSDAY THRU SATURDAY: FAIR BECOMING GOOD.



COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     18   18     400   3     31   23     950   4
FRASER VLY   QUIL     19   19     400   3     29   28    1050   9
SRN VRISL    QUIL     21   16     300   5     25   22     850   4
CNTRL VRISL  QUIL     21   18     350   4     38   26     950   7
NRN VRISL    HRDY      9   14       0   4     14   18     950   4
TERRACE      ANT      30   15     700  15     70   17    1650  15
STEWART      ANT      29   13       0  15     70   17    1650  15

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

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SE  11   S   20   S   31
PORT HARDY   S   20   S   33   S   41
SANDSPIT     S   61   S   63   SW  72

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1700 m         32 C
PORT HARDY      1000 m         24 C
ANNETTE         3400 m         32 C

TODAY'S VENTING: POOR SOUTH TO GOOD NORTH.

VENTING FOR WEDNESDAY: POOR TO GOOD.

VENTING OUTLOOK THURSDAY THRU SATURDAY: GOOD.




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


END/JMS