FPCN39 CWLW 041349
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 4 SEPTEMBER 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      65   16    1200  15     86   22    2200  15
KAMLOOPS     KEL      29   14    1350   5     65   22    1550   6
OKANAGAN     KEL      19    9    1500   9     59   21    1350   5
CASTLEGAR    SPOK      9    8     790   6     64   22    2100   5
CRANBROOK    SPOK      9    7     950   5     93   24    3950   5
REVELSTOKE   KEL      19    8    1100   7     59   17     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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  20   SW  37
CRANBROOK             W   11   W   26

TODAY'S VENTING: BECOMING GOOD BY THE AFTERNOON.

VENTING FOR SUNDAY: 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   12     950   5     80   17    2950   8
PR. GEORGE   P.G.      9   12     800   5     80   16    1650   7
SMITHERS     P.G.      9   12     800   4     64   15    1550   5
WELLS GRAY   P.G.     22    9     800   6     90   17    3000  15
FT NLSN      F.N.    100   12     600   5     84   18    1000   7
FT STJOHN    F.N.    100   14     700   5     93   18    2050  11

*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            SW  26   SW  33
SMITHERS              S   26   S   33

TODAY'S VENTING: BECOMING GOOD BY THE AFTERNOON.


VENTING FOR SUNDAY: FAIR


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     15   14    1750   7     31   19     850   4
FRASER VLY   QUIL     16   16    2000   5     54   22    1100   5
SRN VRISL    QUIL     19   15    1850   7     42   21     750   4
CNTRL VRISL  QUIL     19   15    1850   7     42   21     750   4
NRN VRISL    HRDY     50   13    2050   9     42   16     650   6
TERRACE      ANT       9   12     800   3     30   17    1150   3
STEWART      ANT       9   11     700   3     30   15    1000   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   SW  20   SW  33
PORT HARDY   S   50   SW  65   SW  67
SANDSPIT     S   33   SW  44   SW  44

TODAY'S VENTING: FAIR.


VENTING FOR SUNDAY: FAIR

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

end/lm