FPCN39 CWLW 041400
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 WEDNESDAY 4 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      12   26     500  10    100   32    1600  15
KAMLOOPS     KEL      11   23     500   1     70   30    1500   8
OKANAGAN     KEL      10   22     500   1     70   30    1500   8
CASTLEGAR    SPOK      9   23     500   5    100   30    3500  11
CRANBROOK    SPOK     44   23    1200  17    100   28    3950  12
REVELSTOKE   KEL      10   22     500   1     75   30    1800   6

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   W   13
CRANBROOK             E   13   SE  31

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: 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.      9   21     950   8    100   28    3950   6
PR. GEORGE   P.G.     13   18     750   6     56   28    1500   7
SMITHERS     P.G.     11   19     750   1     65   28    1400   7
WELLS GRAY   P.G.      9   21     950   8    100   28    4000   6
FT NLSN      F.N.      9   23     400   0     55   32    1500   5
FT STJOHN    F.N.      9   20     700   7     55   29    1550   7

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            NE   9   E   15
SMITHERS              E   11   E   15

TODAY'S VENTING: GOOD


VENTING FOR THURSDAY: GOOD


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     68   18     750  12     79   23     950  12
FRASER VLY   QUIL     71   19     800  12     81   24    1000  12
SRN VRISL    QUIL     50   17     600   9     73   22     900  11
CNTRL VRISL  QUIL     71   21     850  11     82   25    1100  11
NRN VRISL    HRDY     14   16     500   1     38   19     700   5
TERRACE      ANT      18   20     650   2     42   26    1400   3
STEWART      ANT      13   19     300   2     50   26    1150   5

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   E   11   SE   9
PORT HARDY   N   19   E   11   SE  26
SANDSPIT     NW  13   SE  13   SE  37

TODAY'S VENTING: GOOD SOUTH TO FAIR NORTH


VENTING FOR THURSDAY: FAIR

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

END/RH
$$$$^^