FPCN39 CWLW 241329
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 FRIDAY 24 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      49   15    1200   5    100   20    3200   8
KAMLOOPS     KEL      35   13     950   5    100   18    3350   8
OKANAGAN     KEL      25   12     700   5    100   17    2850   8
CASTLEGAR    SPOK     44   13     850  12    100   19    2600  14
CRANBROOK    SPOK    100   14    2400  14    100   18    3950  16
REVELSTOKE   KEL      20   11     700   5    100   16    2850   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W   11   W   24   W   39
CRANBROOK             W   15   W   31

TODAY'S VENTING: GOOD THIS AFTERNOON.




VENTING FOR SATURDAY: 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    7    2150  29    100   14    3950  17
PR. GEORGE   P.G.     88    8    1400  19    100   13    3700  15
SMITHERS     P.G.     37    8     850  10    100   13    3500  20
WELLS GRAY   P.G.     40    7     800  10    100   15    4000  17
FT NLSN      F.N.      9    9     550   0    100   18    3400  25
FT STJOHN    F.N.     11   10     700  30    100   14    3700  25

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  28   W   41
SMITHERS              SW  22   SW  41

TODAY'S VENTING: GOOD THIS AFTERNOON.




VENTING FOR SATURDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     62   14    1050   7     89   16    1550   9
FRASER VLY   QUIL     39   13     800   5     83   16    1500   8
SRN VRISL    QUIL     11   12     250   1     75   16    1400   7
CNTRL VRISL  QUIL     31   13     700   4    100   18    1950   9
NRN VRISL    HRDY     21   11     250   6     85   14    1150  11
TERRACE      ANT      10    9     250  14    100   12    1850  15
STEWART      ANT       9    9       0   6     81   12    1000  11

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   20   SW  33   W   46
PORT HARDY   S   65   S   82   SW  89
SANDSPIT     SW  50   W   54   W   52

TODAY'S VENTING: GOOD THIS AFTERNOON.




VENTING FOR SATURDAY: GOOD




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