FPCN39 CWLW 171330
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 MONDAY 17 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       9   15     600   5     79   22    3200  18
KAMLOOPS     KEL       9   16    1300   6     89   23    3350  15
OKANAGAN     KEL       9   14     600   8     93   24    3350  12
CASTLEGAR    SPOK     45   15     950  10    100   24    3500  17
CRANBROOK    SPOK     59   14    1350  15    100   24    3950  20
REVELSTOKE   KEL       9   15    1300   7     91   22    3450  15

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   15   W   19
CRANBROOK             W    9   W   22

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: 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.     72   13    1650  13    100   21    3950   17
PR. GEORGE   P.G.     74   15    1600  10    100   22    3700   18
SMITHERS     P.G.     54   14    1150   9    100   22    3500   22
WELLS GRAY   P.G.     72   13    1750  13    100   20    4000   17
FT NLSN      F.N.     18   16     500   9     43   24     800   19
FT STJOHN    F.N.      9   15     700   9     25   22     950   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            N  11   NW 19
SMITHERS              W  19   NW 25

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: FAIR.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     82   16    1150  11    100   20    1750  13
FRASER VLY   QUIL     61   15     700  11    100   20    1650  13
SRN VRISL    QUIL      9   15     500   0    100   21    1900  11
CNTRL VRISL  QUIL      9   15     550   0     97   19    1550  11
NRN VRISL    HRDY     31   14     300   9     90   18    1350  11
TERRACE      ANT       9   15     250   6    100   22    2050  11
STEWART      ANT      32   16     500   5    100   22    1950   9

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   17   W   19   NW  17
PORT HARDY   NW  19   NW  20   NW  24
SANDSPIT     NW  28   NW  28   NW  24

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: FAIR.


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


END/MWSO