FPCN39 CWLW 301335
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 30 SEPTEMBER 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       9   15     650   0      9   25    1800   0
KAMLOOPS     KEL       9   13     600   0      9   25    2400   0
OKANAGAN     KEL       9   12     550   0      9   23    1700   0
CASTLEGAR    SPOK     16   14     750   3     36   24    1500   3
CRANBROOK    SPOK      9   13     950   8    100   22    3950   9
REVELSTOKE   KEL       9   11     550   0      9   19    1300   0

*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   SW  11
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: POOR EXCEPT EXTREME SOUTHEASTERN SECTION.

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    8     950  17    100   16    3950  16
PR. GEORGE   P.G.     17    8     850   6     58   15    1300  11
SMITHERS     P.G.     25    9     800   6     42   13     950   9
WELLS GRAY   P.G.      9    9    1000  17    100   16    4000  16
FT NLSN      F.N.     35    5     550  15     82   14    3200   9
FT STJOHN    F.N.     42    5    1000  14     85   14    3600   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              SW  46   SW

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     13   13     200   3     21   18     350   5
FRASER VLY   QUIL     14   14     200   3     29   22     550   5
SRN VRISL    QUIL     12   13     200   2     22   20     400   3
CNTRL VRISL  QUIL     13   15     250   2     36   24     750   4
NRN VRISL    HRDY      9   12       0   3     27   15     600   4
TERRACE      ANT      11   10     250  32     11   10     250  32
STEWART      ANT       9   10       0  20      9   10       0  20

*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   SW  13   SW  30
PORT HARDY   S   24   S   43   SW  61
SANDSPIT     S   61   SW  59   SW  57

TODAY'S VENTING: POOR.

VENTING FOR THURSDAY: GOOD.




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


END/MWSO