FPCN39 CWLW 151339
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 15 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      28   21     850   3     53   28    1500   4
KAMLOOPS     KEL      35   22    1050   4     53   28    1700   4
OKANAGAN     KEL      33   21    1000   4     50   27    1550   4
CASTLEGAR    KEL      38   21    1100   5     50   26    1600   5
CRANBROOK    KEL      33   21    1500   5     53   26    3950   5
REVELSTOKE   KEL      29   20    1000   4     35   22    1150   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  13   SW  19
CRANBROOK             VR   5   SW  19

TODAY'S VENTING:poor this morning becoming fair this afternoon.


VENTING FOR THURSDAY: 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.     27   18    1150  10     36   21    1200   5
PR. GEORGE   P.G.     21   16     950   5     24   19    1000   5
SMITHERS     P.G.     14   15     900   1     20   17     950   3
WELLS GRAY   P.G.     14   14    1000   3     87   21    2050  10
FT NLSN      F.N.      9   15     550   0     34   18     700   8
FT STJOHN    F.N.     40   16     950  15    100   21    3700  13


FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
                       1800m    2700m
PR. GEORGE            W   19   SW  30
SMITHERS              SW  37   SW  30

TODAY'S VENTING:POOR EXCEPT GOOD IN THE PEACE DISTRICT.


VENTING FOR THURSDAY: FAIR




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     56   17     850   8     60   20     900   8
FRASER VLY   QUIL     59   19     850   8     68   24    1050   8
SRN VRISL    QUIL      9   18     850   0     49   21     900   0
CNTRL VRISL  QUIL      9   19     850   0     49   23    1000   5
NRN VRISL    HRDY     65   16     800   9     64   15     800   9
TERRACE      ANT     100   16    1100  23    100   17    1250  14
STEWART      ANT      77   15     650  16    100   17     950  10

*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    W   13   W   19   W   19
PORT HARDY   SW  11   SW  22   W   30
SANDSPIT     W   17   W   26   W   31

TODAY'S VENTING:FAIR EXCEPT GOOD ON THE NORTH COAST.


VENTING FOR THURSDAY: FAIR




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





END/lm