FPCN39 CWLW 141341
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 TUESDAY 14 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      23   15    1400   8     44   30    1550   6
KAMLOOPS     KEL      20   14    1450   8     47   27    1500   5
OKANAGAN     KEL      66   13    1350   8     43   25    1550   4
CASTLEGAR    SPOK     28   13    1000   4     38   26    1300   4
CRANBROOK    SPOK     35   13    1650   4     39   24    1500   4
REVELSTOKE   KEL      62   12    1350   8     42   22    1350   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW   9   SW  19
CRANBROOK             VR   5   NW  13

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

VENTING FOR WEDNESDAY: 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.     15   8      950   3     52   23    1100   5
PR. GEORGE   P.G.     15   7      700   4     52   22    1100   5
SMITHERS     KEL      24   7      650   2     64   20    1250   4
WELLS GRAY   KEL      14   14    1000   3     63   23    1850   9
FT NLSN      F.N.      9    7     400   1      9   20     400   1
FT STJOHN    F.N.     21   10     750   3    100   22    1900   9

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

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   19   SW  30
SMITHERS              SW  22   SW  30

TODAY'S VENTING: poor becoming fair this afternoon.

VENTING FOR WEDNESDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     15   18     500   2     16   21     550   2
FRASER VLY   QUIL     16   15     550   2     23   28     900   2
SRN VRISL    QUIL     14   15     500   1     14   21     550   1
CNTRL VRISL  QUIL     14   21     550   1     15   26     600   1
NRN VRISL    HRDY     28   18     600   4     28   18     600   4
TERRACE      ANT      45   19    1250   4     45   19    1250   4
STEWART      ANT      51   20    1100   5     47   19    1000   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   SW  15   SW  20
PORT HARDY   NW  11   W   13   SW  24
SANDSPIT     W   22   SW  37   SW  59

TODAY'S VENTING:poor becoming fair on the north coast.


VENTING FOR WEDNESDAY: GOOD

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


END/lm