FPCN39 CWLW 231400
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 23 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      25   21     650   4     77   24     850  18
KAMLOOPS     KEL      30   22     850   5     70   24     950  15
OKANAGAN     KEL      12   14     500   2     63   23     900  14
CASTLEGAR    SPOK     20   15     800   4     71   22    1200  12
CRANBROOK    SPOK      9   17     950  14    100   25    3950  14
REVELSTOKE   KEL      10   13     500   2     62   17     600  12

*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    W   15   W   33   W   56
CRANBROOK             W   20   W   48

TODAY'S VENTING: GOOD

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.    100   15    2500  22    100   18    3950  25
PR. GEORGE   P.G.      9   13     700  13     86   15    1450  17
SMITHERS     P.G.      9   10     500  10     84   13    1650  15
WELLS GRAY   P.G.     35   08     700  20    100   17    4000  25
FT NLSN      F.N.     34   13     700  12     46   18    1700  15
FT STJOHN    F.N.      9   15     700  19    100   17    1850  23

*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   41   W   56
SMITHERS              SW  43   W   56

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: FAIR TO GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     56   15     650  10     66   18     800  11
FRASER VLY   QUIL     44   14     500  10     62   17     750  10
SRN VRISL    QUIL     50   15     650   8     54   17     700  14
CNTRL VRISL  QUIL     32   14     400   7     54   17     700  15
NRN VRISL    HRDY     11   11     100   3     61   15     350  17
TERRACE      ANT      98   10     850  26    100   12    1800  26
STEWART      ANT      19   10     100   9     95   12     800  19
*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   17   W   31   W   54
PORT HARDY   W   26   W   35   W   43
SANDSPIT     W   56   W   65   W   63

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: FAIR TO GOOD

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

$$$$^^