FPCN39 CWLW 051441
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 FRIDAY 5 DECEMBER 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    0     200   0      9    2    1050   0
KAMLOOPS     KEL       9    0     800   0      9    1    1200   0
OKANAGAN     KEL       9    0     750   0      9    3    1300   0
CASTLEGAR    SPOK     13    0     900   2     18    1     950   2
CRANBROOK    SPOK      9   -6     950   8      9   -4     950   8
REVELSTOKE   KEL       9   -2     450   0      9    0    1200   0

*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   SE  11   S   15
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: POOR

VENTING FOR SATURDAY: POOR

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   -5     950   9     24   -1    1100   9
PR. GEORGE   P.G.     24   -7     850   9     27   -5     900   9
SMITHERS     P.G.     30   -3     900   6     33   -1     950   6
WELLS GRAY   P.G.      9   -5    1000   9      9   -4    1000   9
FT NLSN      F.N.      9  -13     400  10      9  -12     400  10
FT STJOHN    F.N.      9   -9     700  10      9   -5     700  10

*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            S   26   SW  28
SMITHERS              S   22   SW  28

TODAY'S VENTING: POOR

VENTING FOR SATURDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9    4     100   6     18    9     250   6
FRASER VLY   QUIL      9    6      50   6     19    9     250   6
SRN VRISL    QUIL     12    5      50   6     23   10     250   6
CNTRL VRISL  QUIL      9    3      50   6     15    7     150   6
NRN VRISL    HRDY      9    5       0   7     27    9     300   7
TERRACE      ANT       9    2       0   5     27    4     300   9
STEWART      ANT       9    2       0   1      9    2       0   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    E   20   SE  19   S   19
PORT HARDY   SE  15   S   15   SW  26
SANDSPIT     SW  19   S   26   S   31

TODAY'S VENTING: POOR

VENTING FOR SATURDAY: POOR

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


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