FPCN39 CWLW 251322
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 SATURDAY 25 JULY 1998 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      15   24     500   2     56   35    1950   3
KAMLOOPS     KEL      13   25     550   2     82   38    3350   4
OKANAGAN     KEL      13   25     550   2     82   38    3350   4
CASTLEGAR    SPOK     22   25     750   5     80   36    3500   4
CRANBROOK    SPOK      9   21     950   7     77   33    3950   3
REVELSTOKE   KEL      11   24     550   2     82   36    3450   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   NW  11
CRANBROOK             VR   5   NW   9

TODAY'S VENTING: GOOD.




VENTING FOR SUNDAY: 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.     41   19    1250  11    100   30    3950  13
PR. GEORGE   P.G.      9   18     700   2    100   29    3700  11
SMITHERS     P.G.     14   18     800   2    100   27    2500  10
WELLS GRAY   P.G.     78   20    2100  10    100   31    4000  13
FT NLSN      F.N.     43   19     550  22    100   26    3400  30
FT STJOHN    F.N.      9   17     700  24    100   27    3700  31

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

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE   NW 17    NW  17   W  36
SMITHERS              W   13   W

TODAY'S VENTING: GOOD.




VENTING FOR SUNDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     52   19     600  10     74   25    1050  10
FRASER VLY   QUIL     59   21     700  10     88   31    1700   8
SRN VRISL    QUIL      9   17     500   0      9   24     850   0
CNTRL VRISL  QUIL      9   22     750   0     84   33    2100   6
NRN VRISL    HRDY     49   16     600   9     64   21     800   9
TERRACE      ANT      87   19    1750   9    100   28    2800  11
STEWART      ANT      50   19    1300   4    100   28    2400   9

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

FORECAST UPPER WINDS FOR SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   VR   5   VR   5
PORT HARDY   N   31   N   22   N   17
SANDSPIT     NW  28   NW  26   NW  30

TODAY'S VENTING: POOR TO FAIR.




VENTING FOR SUNDAY: GOOD




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


END/