FPCN39 CWLW 111329
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 PDT TUESDAY 11 AUGUST 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   21     500   1     97   30    2550   7
KAMLOOPS     KEL      10   19     500   1    100   30    3350   7
OKANAGAN     KEL      11   20     500   1    100   31    3350   7
CASTLEGAR    SPOK     21   20     750   5     68   30    1400   9
CRANBROOK    SPOK      9   18     950  12    100   30    3950  13
REVELSTOKE   KEL       9   17     450   1     87   26    2400   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   13   W   19
CRANBROOK             W    9   W   17

TODAY'S VENTING: GOOD




VENTING FOR WEDNESDAY: 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.     20   14    1100   7    100   23    3950  11
PR. GEORGE   P.G.     10   13     800   1     88   19    2550   7
SMITHERS     P.G.      9   11     500   1     28   17     950   5
WELLS GRAY   P.G.     88   16    2550   9    100   23    4000  11
FT NLSN      F.N.      9   13     400  24    100   23    3400  28
FT STJOHN    F.N.      9   12     700  24    100   21    3700  28

*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              SW  48   SW

TODAY'S VENTING: GOOD




VENTING FOR WEDNESDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     36   20     900   4     51   25    1350   4
FRASER VLY   QUIL     35   19     750   4     62   27    1650   4
SRN VRISL    QUIL     29   18     550   4     46   24    1200   4
CNTRL VRISL  QUIL     24   17     400   4     44   23    1150   4
NRN VRISL    HRDY     15   14     150   5     28   17     350   6
TERRACE      ANT       9   12     200  15    100   17    3200  15
STEWART      ANT      17   14     250   4    100   17    1600  13

*SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING
HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS.

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   13   W   20   W   28
PORT HARDY   S   54   SW  50   SW  54
SANDSPIT     SW  54   SW  57   SW  65

TODAY'S VENTING: GOOD




VENTING FOR WEDNESDAY: GOOD




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


END/JL