FPCN39 CWLW 221431
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 22 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       9   21     600   0     58   28    1950   10
KAMLOOPS     KEL      12   20     600   1     61   28    2550   5
OKANAGAN     KEL       9   19     550   0     70   27    2200   5
CASTLEGAR    SPOK     17   19     750   3     48   27    1150   3
CRANBROOK    SPOK      9   18     950   5    100   27    2950   5
REVELSTOKE   KEL       9   17     500   0     36   22    1150   4

*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   SW  13   SW  28
CRANBROOK             W   13   W   35

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          670 m         21 C
SPOKANE         1200 m         26 C

TODAY'S VENTING: POOR THIS MORNING BECOMING GOOD BY THE
AFTERNOON EXCEPT ONLY FAIR IN THE COLUMBIAS.

VENTING FOR SATURDAY: FAIR

VENTING OUTLOOK SUNDAY THRU TUESDAY:GOOD ON SUNDAY AS A TROUGH MOVES
THROUGH THEN FAIR TO GOOD IN A SOUTHWESTERLY FLOW.


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   17    1200   5     80   23    3950  10
PR. GEORGE   P.G.     40   16    1050   5     80   20    2450  10
SMITHERS     P.G.     37   16     850  10     80   21    2150  10
WELLS GRAY   P.G.    100   15    1450  15     80   24    4000  20
FT NLSN      F.N.     21   17     500   9     48   22     950   8
FT STJOHN    F.N.      9   15     700   8     17   18     800   8

*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  24   W   37
SMITHERS              SW  33   SW  37

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       850 m         16 C
FT. NELSON       880 m         22 C

TODAY'S VENTING: BEOCMING GOOD BY THE AFTERNOON.

VENTING FOR SATURDAY: FAIR

VENTING OUTLOOK SUNDAY THRU TUESDAY: FAIR TO GOOD.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     31   19     300  10    100   23    1750  12
FRASER VLY   QUIL     31   19     300  10    100   25    1800  12
SRN VRISL    QUIL      9   17     200   0     49   22     750   5
CNTRL VRISL  QUIL      9   18     250   0     49   22     800   5
NRN VRISL    HRDY     16   16     150   5     45   20     800   5
TERRACE      ANT      88   17    1000  18    100   20    1500  20
STEWART      ANT      51   16     400  12    100   20    1150  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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   SW  11   SW  31
PORT HARDY   SW  15   S   22   SW  24
SANDSPIT     SW  41   SW  46   SW  56

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       300 m         19 C
PORT HARDY       500 m         19 C
ANNETTE          790 m         17 C

TODAY'S VENTING: POOR BECOMING GOOD IN THE EARLY AFTERNOON EXCEPT
FAIR ON VANCOUVER ISLAND.

VENTING FOR SATURDAY: FAIR

VENTING OUTLOOK SUNDAY THRU TUESDAY:FARI TO GOOD IN A SOUTWESTERLY
FLOW.

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

END/LM