FPCN39 CWLW 281323
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 28 JULY 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   28     600   0     99   40    3200   5
KAMLOOPS     KEL       9   24     500   0     79   38    2350   5
OKANAGAN     KEL       9   25     550   0     45   35    1450   5
CASTLEGAR    SPOK     26   26     800   6     90   38    3500   5
CRANBROOK    SPOK      9   20     950   4     93   35    3950   5
REVELSTOKE   KEL       9   23     500   0     60   35    1600   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   S   13

TODAY'S VENTING: FAIR TO 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.      9   20     950   6    100   33    3950   6
PR. GEORGE   P.G.      9   20     700   2    100   32    3700   6
SMITHERS     P.G.     13   19     750   2     68   31    1800   6
WELLS GRAY   P.G.     16   21    1100   6    100   33    4000   6
FT NLSN      F.N.      9   15     400  23     80   23    1750  15
FT STJOHN    F.N.     43   16     850  23    100   25    3700  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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              VR   5   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     23   22     250   9     20   28     500   5
FRASER VLY   QUIL     33   25     350   9     90   34    3000   5
SRN VRISL    QUIL      9   20     200   0     15   28     500   5
CNTRL VRISL  QUIL      9   25     350   0     15   35     800   5
NRN VRISL    HRDY     18   17     200   5     32   23     350   8
TERRACE      ANT      79   21     650  26    100   33    3200  19
STEWART      ANT      70   22     550  16    100   33    3000  18

*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    9   NW  11   NW  13
PORT HARDY   NW  22   NW  17   NW  13
SANDSPIT     N   46   NW  28   NW  22

TODAY'S VENTING: GOOD INLAND. POOR ALONG THE COAST.

VENTING FOR WEDNESDAY: GOOD

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

END/