FPCN39 CWLW 111433
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 11 MARCH 1999 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      17    3     600   2     37    9    1750   2
KAMLOOPS     KEL      19    3     850   2     37   10    1850   2
OKANAGAN     KEL      19    3     850   2     36    8    1850   2
CASTLEGAR    SPOK     22    1     750   5     37    7    1950   2
CRANBROOK    SPOK     10    0     950   9     88    6    3950   4
REVELSTOKE   KEL      13    1     650   2     32    6    1700   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    VR   5   S    9   S   13
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: FAIR.

VENTING FOR FRIDAY: POOR TO 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    0     950   8    100    5    3950  10
PR. GEORGE   P.G.     21    1     800  10    100    6    2700   9
SMITHERS     P.G.     16    1     650   6     46    4    1050   9
WELLS GRAY   P.G.      9    0    1000   8    100    5    4000  10
FT NLSN      F.N.      9   -5     500   0     24    5     800   4
FT STJOHN    F.N.      9   -2     700   7     17    2     800   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            S   37   S   43
SMITHERS              S   54   S   43

TODAY'S VENTING: GOOD SOUTH. POOR NORTH.

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     18    5     250   6     94   11    1800   9
FRASER VLY   QUIL     19    5     250   6     79   10    1250   9
SRN VRISL    QUIL     22    6     250   6     87   11    1550   9
CNTRL VRISL  QUIL     23    7     300   6     89   11    1600   9
NRN VRISL    HRDY     44    6     300  14     98    8    1000  17
TERRACE      ANT      10    2     200  14     10    3     200  34
STEWART      ANT      10    2     100  14      9    3       0  27

*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    S   20   S   28   S   35
PORT HARDY   S   70   S   93   S   89
SANDSPIT     S   65   S   80   S  102

TODAY'S VENTING: GOOD SOUTH. POOR NORTH.

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/