FPCN39 CWLW 041323
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 SUNDAY 4 JULY 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      36   16    1100   3    100   21    3200   6
KAMLOOPS     KEL      55   16    1650   4    100   21    3350   6
OKANAGAN     KEL      41   15    1300   4    100   20    3350   6
CASTLEGAR    SPOK     37   15    1050   6    100   21    3500   7
CRANBROOK    SPOK     62   13    2050   6    100   20    3950   8
REVELSTOKE   KEL      15   12     650   3    100   17    3450   6

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W    9   W   15   NW  20
CRANBROOK             W    9   W   20

TODAY'S VENTING: GOOD




VENTING FOR MONDAY: 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   12     950   4     28   16    1500   4
PR. GEORGE   P.G.     14   11     750   6     25   14     950   7
SMITHERS     P.G.     15   11     750   3     18   14     850   3
WELLS GRAY   P.G.     20    8     750   5     67   16    2300   6
FT NLSN      F.N.    100   11    1300  21    100   15    2150  20
FT STJOHN    F.N.    100   13    2200  20    100   17    3700  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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   35   W   44
SMITHERS              W   31   NW  44

TODAY'S VENTING: POOR




VENTING FOR MONDAY: GOOD



COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     31   14     900   3     82   18    3100   4
FRASER VLY   QUIL     31   14     850   3     82   19    3050   4
SRN VRISL    QUIL     30   14     800   3     52   18    1450   4
CNTRL VRISL  QUIL     36   15     950   3     80   19    3050   4
NRN VRISL    HRDY     43   14     750   6     48   16     900   5
TERRACE      ANT      62   16     850  11     71   21    1150  10
STEWART      ANT      68   16     700  12     79   21    1050  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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  22   W   22   NW  22
PORT HARDY   SW  17   W   19   NW  28
SANDSPIT     NW  28   NW  35   NW  39

TODAY'S VENTING: GOOD




VENTING FOR MONDAY: GOOD




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



END/RAM