FPCN39 CWLW 071433
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 Sunday 7 September 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      41   18     850   5     64   24    1650   5
KAMLOOPS     KEL      44   18    1100   6     56   24    1800   6
OKANAGAN     KEL      32   16     800   5     50   23    1500   5
CASTLEGAR    SPOK     25   15     800   5     63   23    2100   5
CRANBROOK    SPOK      9   13     950   5     74   21    2950   4
REVELSTOKE   KEL       9   11     500   3     51   20    1450   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   W   15
CRANBROOK             VR   5   W   17

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1700 m         21 C
SPOKANE         1000 m         18 C

TODAY'S VENTING:Poor to fair this morning becoming briefly good
in the late afternoon.

VENTING FOR MONDAY: poor

VENTING OUTLOOK TUESDAY THRU THURSDAY:Poor to briefly fair in the
afternoons as a ridge of high pressure produces stagnate venting
conditions.

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.     39   12    1500   6     90   17    3950   5
PR. GEORGE   P.G.     15    9     800   5     81   16    2350   7
SMITHERS     P.G.     13    8     750   2     26   14     950   4
WELLS GRAY   P.G.     24   11    1250   6    100   18    4000  19
FT NLSN      F.N.      9   13     400  16    100   20    2450  18
FT STJOHN    F.N.      9   12     700  17     78   16    1350  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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            VR   5   NW  11
SMITHERS              VR   5   SW  11

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1000 m         16 C
FT. NELSON       700 m         18 C

TODAY'S VENTING: Poor this morning becoming briefly goodd by mid
afternoon except poor in the northwest.

VENTING FOR MONDAY: fair.

VENTING OUTLOOK TUESDAY THRU THURSDAY: Fair in the afternoons as
a ridge of high pressure produces stagnate venting conditions.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     11   17     250   1     29   21    1250   2
FRASER VLY   QUIL     11   17     250   1     42   24    1800   2
SRN VRISL    QUIL     10   16     200   1     19   21     800   1
CNTRL VRISL  QUIL     10   17     250   1     35   22    1550   2
NRN VRISL    HRDY     12   14     150   2     17   17     350   3
TERRACE      ANT      40   15     900   5     70   17    1350   7
STEWART      ANT      13   15     100   5     70   16    1300   7

*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    VR   5   VR   5   VR   5
PORT HARDY   VR   5   SE  15   S    9
SANDSPIT     S   41   S   31   S   24

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       800 m         20 C
PORT HARDY       600 m         15 C
ANNETTE          130 m         15 C

TODAY'S VENTING: fair except good on the north coast.

VENTING FOR MONDAY: fair

VENTING OUTLOOK TUESDAY THRU THURSDAY: Fair in the afternoons as
a ridge of high pressure produces stagnate venting conditions.


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

END/lm