FPCN39 CWLW 091400
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 THURSDAY 9 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      27   18     750   4    100   24    2000   13
KAMLOOPS     KEL      42   17     800  10     89   23    1350   13
OKANAGAN     KEL      19   14     550   5     55   24    1650   5
CASTLEGAR    SPOK     19   15     750   4     37   24    1150   5
CRANBROOK    SPOK      9   13     950   8     54   23    1700   5
REVELSTOKE   KEL      15   13     550   5     34   18    1500   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   17   W   28
CRANBROOK             SW  17   SW  43

TODAY'S VENTING: GOOD OVER WESTERN SECTIONS AND FAIR OVER EASTERN
SECTIONS.

VENTING FOR FRIDAY: 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.     68   15    1650  12    100   18    3950  15
PR. GEORGE   P.G.     22   12     800  10    100   14    1950  12
SMITHERS     P.G.      9   10     500   5    100   12    2500  10
WELLS GRAY   P.G.     14    5    1100   2    100   19    4000  15
FT NLSN      F.N.      9   11     400   0    100   15    2450  10
FT STJOHN    F.N.     14   12     900   3    100   15    2350  15

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   31   W   43
SMITHERS              SW  31   W   43

TODAY'S VENTING: GOOD.

VENTING FOR FRIDAY: GOOD


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     72   16     600  17     87   18     850  17
FRASER VLY   QUIL     59   14     450  17     89   19     950  16
SRN VRISL    QUIL      9   14     400   0     88   18    1200  12
CNTRL VRISL  QUIL      9   16     550   0     81   20    1000  12
NRN VRISL    HRDY     71   14     750  12     97   16    1200  14
TERRACE      ANT      11   10     400   5     90   ##    2000  10
STEWART      ANT       9    9     400   2     85   ##    2000   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   19   NW  20   W   24
PORT HARDY   NW  20   NW  28   NW  37
SANDSPIT     SW  30   W   41   W   44

TODAY'S VENTING: GOOD.

VENTING FOR FRIDAY: GOOD


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


END/mwso/tal
$$$$^^