FPCN39 CWLW 111326
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 11 SEPTEMBER 1998 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      50   17     450  18    100   24    1450  20
KAMLOOPS     KEL       9   16     450   0    100   24    2500  10
OKANAGAN     KEL       9   16     450   0    100   24    2500  10
CASTLEGAR    SPOK     26   17     750   7     79   26    2550   5
CRANBROOK    SPOK      9   15     950   6     89   25    3950   5
REVELSTOKE   KEL       9   15     450   0     92   22    2050   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   15   W   22
CRANBROOK             W    9   W   20

TODAY'S VENTING: GOOD

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.     10   14     950  26    100   20    3950  28
PR. GEORGE   P.G.     26   14     800  18     75   18    1150  21
SMITHERS     P.G.      9   12     500   9     71   17     950  21
WELLS GRAY   P.G.     76   16    1400  26    100   21    4000  28
FT NLSN      F.N.      9   10     400  14     71   18    1050  14
FT STJOHN    F.N.      9   12     700  13     95   17    1850  14

*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
SMITHERS              SW  39   SW

TODAY'S VENTING: GOOD

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     41   16     400  12     83   21    1050  12
FRASER VLY   QUIL     40   16     350  12     87   22    1150  12
SRN VRISL    QUIL      9   16     300   0     70   22    1100   8
CNTRL VRISL  QUIL      9   15     200   0     55   19     750   8
NRN VRISL    HRDY     22   14     300   5     52   17     650   8
TERRACE      ANT      10   10     220  15     99   13    1350  15
STEWART      ANT      20   12     100  11     53   13     350  16

*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    W   11   W   19   W   26
PORT HARDY   SW  13   SW  22   W   39
SANDSPIT     SW  33   SW  41   W   50

TODAY'S VENTING: GOOD TO FAIR.

VENTING FOR SATURDAY: GOOD

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


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