FPCN39 CWLW 291434
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 29 OCTOBER 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       9    5     500   0     37   10    1150   3
KAMLOOPS     KEL       9    3     500   0     41    9    1350   4
OKANAGAN     KEL       9    4     550   0     68   12    2200   4
CASTLEGAR    SPOK     24    6    1000   3     83   12    2550   6
CRANBROOK    SPOK      9    3     950   6    100   10    3950   7
REVELSTOKE   KEL      12    5     650   2     28    7    1050   3

*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    VR   5   SW  13   W   22
CRANBROOK             VR   5   W   15

TODAY'S VENTING: FAIR TO GOOD.

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.     10    0     950  21     50    4    1300  10
PR. GEORGE   P.G.     18    2     800   8     50    4    1150  10
SMITHERS     P.G.      9    0     500   3     45    5    1400   5
WELLS GRAY   P.G.     50    2    1350  15     50    5    1500  15
FT NLSN      F.N.      9   -4     400  15     26    0     500  15
FT STJOHN    F.N.     90   -1    1200  15     90    3    1250  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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   24   W   37
SMITHERS              VR   5   W   37

TODAY'S VENTING: FAIR EXCEPT GOOD IN FORT ST JOHN.

VENTING FOR FRIDAY: FAIR.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     27    8     250  12     67   11     600  16
FRASER VLY   QUIL      9    7      50  12     94   12     900  18
SRN VRISL    QUIL     18    7     150   7     60   11     600  13
CNTRL VRISL  QUIL     25    8     200  10     60   11     600  13
NRN VRISL    HRDY      9    8       0  16     78   11     600  18
TERRACE      ANT       9    4     250   6     50    7    1300   5
STEWART      ANT      11    6     100   3     50    7     750   5

*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    SE  19   SW  26   SW  28
PORT HARDY   SW  11   SW  15   W   19
SANDSPIT     VR   5   VR   5   VR   5

TODAY'S VENTING: GOOD EXCEPT FAIR ON THE NORTH COAST.

VENTING FOR FRIDAY: FAIR TO GOOD.




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


END/JDG