FPCN39 CWLW 291531
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 PST WEDNESDAY 29 OCTOBER 1997 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      60    9     500  20     85   10     800  20
KAMLOOPS     KEL      26    9     650   6     60   11    1100  10
OKANAGAN     KEL      13    8     500   2     57   10    1100  10
CASTLEGAR    SPOK      9    6     500  13     49    8    1100   9
CRANBROOK    SPOK     11    6     950  33     41    8    1200  10
REVELSTOKE   KEL      11    7     500   2     30    8     700   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W   13   W   35   W   72
CRANBROOK             W   26   W   69

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          650 m          8 C
SPOKANE         NONE

TODAY'S VENTING: FAIR

VENTING FOR THURSDAY: FAIR

VENTING OUTLOOK FRIDAY THRU SUNDAY: FAIR

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.     17    6    1000  13     89    9    1700  18
PR. GEORGE   P.G.     10    5     700  20     85    8    1500  15
SMITHERS     P.G.     19    5     700   6     61    7    1200  10
WELLS GRAY   P.G.     28    6    1200  10     86    9    1750  18
FT NLSN      F.N.     50   -5     900  10     57   -3    1000  10
FT STJOHN    F.N.     65   -1    1400  11     75    1    1500  13

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   48   W   61
SMITHERS              SW  48   SW  61

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1700 m         13 C
FT. NELSON      1300 m          0 C

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: FAIR

VENTING OUTLOOK FRIDAY THRU SUNDAY: FAIR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     46   11     300  20    100   13     900  25
FRASER VLY   QUIL     34   11     200  20    100   12     800  25
SRN VRISL    QUIL     55   11     350  20    100   14     950  25
CNTRL VRISL  QUIL     56   11     300  20     80   12     600  20
NRN VRISL    HRDY      9    9       0  24     80   11     500  24
TERRACE      ANT       9    6     200  37     65    9     600  18
STEWART      ANT       9    8       0  14     70    9     500  18

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  31   SW  48   W   59
PORT HARDY   S   48   SW  57   SW  61
SANDSPIT     S   67   S   69   SW  67

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1300 m         15 C
PORT HARDY       350 m         10 C
ANNETTE         NONE

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: FAIR

VENTING OUTLOOK FRIDAY THRU SUNDAY:

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


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