FPCN39 CWLW 011433
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 8:00 AM PDT Friday 1 August 1997 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      18   22     600   2    100   30    3200  15
KAMLOOPS     KEL      22   22     850   3     97   30    3350   5
OKANAGAN     KEL      16   21     650   2     97   29    3350   5
CASTLEGAR    SPOK     26   21     800   6     86   29    2200   8
CRANBROOK    SPOK      9   20     950  10    100   27    3950  10
REVELSTOKE   KEL      14   19     600   3     74   25    2300   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   SW  15
CRANBROOK             VR   5   W   17

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          650 m         23 C
SPOKANE         1100 m         25 C

TODAY'S VENTING: GOOD
VENTING FOR SATURDAY: GOOD
VENTING OUTLOOK SUNDAY THRU TUESDAY: GENERALLY 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.     40   14    2650   5    100   23    3950   7
PR. GEORGE   P.G.     50   15    2250   8    100   23    3700   8
SMITHERS     P.G.     30   15    1700   3    100   22    3500   5
WELLS GRAY   P.G.     40   16    4000   5    100   24    4000   7
FT NLSN      F.N.     51   14     950   2     80   18    1250   9
FT STJOHN    F.N.     52   15    1250   9    100   21    3700  12

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  11   SW  20
SMITHERS              VR   5   SW  20

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       875 m         12 C
FT. NELSON      1200 m         17 C

TODAY'S VENTING: GOOD
VENTING FOR SATURDAY: GOOD
VENTING OUTLOOK SUNDAY THRU TUESDAY: GENERALLY GOOD


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     50   18     600  10     75   23    1550   7
FRASER VLY   QUIL     43   17     450  10     80   25    1750   7
SRN VRISL    QUIL     33   17     450   6     72   23    1450   6
CNTRL VRISL  QUIL     33   17     450   6     66   22    1300   6
NRN VRISL    HRDY     21   14     150   8     81   17    1600   9
TERRACE      ANT      ##   ##     ###  ##    100   19    3200  11
STEWART      ANT      29   15     350   7     99   19    1700  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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   S   13   S   24
PORT HARDY   VR   5   S   24   S   30
SANDSPIT     SE  13   SE  19   SE  20

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       775 m         20 C
PORT HARDY       600 m         18 C
ANNETTE         NONE m         14 C

TODAY'S VENTING: GOOD
VENTING FOR SATURDAY: GOOD
VENTING OUTLOOK SUNDAY THRU TUESDAY: GENERALLY GOOD


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

END/MWSO