FPCN39 CWLW 131327
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 13 AUGUST 1999 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      20   19     750   2     61   24    2250   4
KAMLOOPS     KEL      35   21    1550   2     71   25    2400   4
OKANAGAN     KEL      20   19    1100   2     70   25    2400   4
CASTLEGAR    SPOK     25   17     900   5    100   24    3500  10
CRANBROOK    SPOK      9   15     950   6    100   22    3950  12
REVELSTOKE   KEL      14   16     700   3     73   20    3200   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
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: GENERALLY GOOD BY MIDDAY.




VENTING FOR SATURDAY: 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.     44   14    1350  10    100   19    3950   6
PR. GEORGE   P.G.     13   15    1000   2     66   19    2250   5
SMITHERS     P.G.     11   14     700   1     58   20    2050   4
WELLS GRAY   P.G.     12   15     800   3    100   20    4000   6
FT NLSN      F.N.     35   16     650  11     84   24    1300  13
FT STJOHN    F.N.      9   15     700  17     42   20     950  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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   11   SW  15
SMITHERS              SW  15   W   15

TODAY'S VENTING: GOOD BY AFTERNOON EXCEPT FAIR IN THE PEACE.




VENTING FOR SATURDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     34   18    1150   3     72   20    3100   3
FRASER VLY   QUIL     33   18    1100   3     72   22    3050   3
SRN VRISL    QUIL     18   16     600   2     55   20    2650   2
CNTRL VRISL  QUIL     20   17     800   2     65   20    3050   3
NRN VRISL    HRDY     55   15     550  10     59   17     850   8
TERRACE      ANT      24   16     600   4     57   22    1550   5
STEWART      ANT      ##   ##     ###  ##     44   22     950   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW   9   VR   5   VR   5
PORT HARDY   NW  15   NW   9   VR   5
SANDSPIT     SW  26   W   20   W   24

TODAY'S VENTING: GOOD BY AFTERNOON EXCEPT FAIR EXTREME NORTH.




VENTING FOR SATURDAY: GOOD.




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

END/TCS