FPCN39 CWLW 311418
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 SATURDAY 31 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      12    6     500   1     61   12    1300   6
KAMLOOPS     KEL      11    6     550   1     71   12    1800   6
OKANAGAN     KEL      10    4     450   1     71   12    1800   6
CASTLEGAR    SPOK     13    5     900   1     51   11    1750   4
CRANBROOK    SPOK      9    0     950   7     57    8    1950   6
REVELSTOKE   KEL      10    5     550   1     19    6     650   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S    9   S   22   SW  39
CRANBROOK             SW   9   W   19

TODAY'S VENTING: GOOD IN THE WEST. POOR TO FAIR IN THE EAST.

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.     45    4    1550   7     98    8    2500  11
PR. GEORGE   P.G.     23    3    1100   4     42    6    1500   5
SMITHERS     P.G.      9    2     550   1     36    4    1200   8
WELLS GRAY   P.G.     47    4    1650   7    100    8    2650  11
FT NLSN      F.N.      9   -5     400  21     47   -1     600  21
FT STJOHN    F.N.      9   -4     700  21     70    0    1650  12

*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   44   S   41
SMITHERS              S   54   S   41

TODAY'S VENTING: GOOD IN THE SOUTH. FAIR IN THE NORTH.

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     18    8     200   9     32   11     350  10
FRASER VLY   QUIL     16    6     150   9     29   11     300   9
SRN VRISL    QUIL     18    6     150   8     29   11     250   9
CNTRL VRISL  QUIL     22    9     200   9     29   11     300   9
NRN VRISL    HRDY      9    8       0  19     60   10     400  19
TERRACE      ANT       9    3     200  29     29    4     200  29
STEWART      ANT       9    5       0  16     19    4     1000  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    SE  31   S   50   S   52
PORT HARDY   S   91   S  109   SW  98
SANDSPIT     S   59   S   67   S   72

TODAY'S VENTING: GOOD IN EXPOSED COASTAL AREAS OTHERWISE POOR.

VENTING FOR SATURDAY: GOOD

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


END/MWSO