FPCN39 CWLW 201607
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 THURSDAY 20 NOVEMBER 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       9    3     200   0     44    6    1050   5
KAMLOOPS     KEL       9    3     500   0     37    5     950   5
OKANAGAN     KEL       9    2     450   0     35    4     800   4
CASTLEGAR    SPOK      9    3     500   2     30    4     500   5
CRANBROOK    SPOK      9    0    1050   4     30    2     950   6
REVELSTOKE   KEL       9    1     450   0     25    3     800   2

*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   11   W   33   W   65
CRANBROOK             W   19   W   57

TODAY'S VENTING: FAIR.

VENTING FOR FRIDAY: 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.      9   -3     950   6     14   -2     950   6
PR. GEORGE   P.G.      9   -3     800   0     13   -3     800   4
SMITHERS     P.G.     17   -1     850   3     17   -1     850   3
WELLS GRAY   P.G.      9   -2    1000   6     22   -2    1000   6
FT NLSN      F.N.     13  -13     400   6     13  -12     400   7
FT STJOHN    F.N.     22   -8     900   5     35   -7     950   7

*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   26   W   31
SMITHERS              W   30   W   31

TODAY'S VENTING: POOR.

VENTING FOR FRIDAY: POOR.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9    9     100   6     22   11     150   6
FRASER VLY   QUIL      9    8      50   6     22   11     100   6
SRN VRISL    QUIL     10    9      50   2     21   11     100   2
CNTRL VRISL  QUIL      9    8      50   2     19   10     100   2
NRN VRISL    HRDY      9    7      50   6     20    9     100   6
TERRACE      ANT       9    0     200   5     15    2     200   5
STEWART      ANT       9    3      50   1     13    2      50   1

*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    SW  26   W   37   W   46
PORT HARDY   SW  20   SW  26   SW  31
SANDSPIT     SW  19   SW  11   VR   5

TODAY'S VENTING: POOR.

VENTING FOR FRIDAY: FAIR TO POOR.

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


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