FPCN39 CWLW 031434
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 3 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   22     700   0     73   31    1900   8
KAMLOOPS     KEL      13   23    1100   1    100   32    3350   7
OKANAGAN     KEL       9   21     750   0     88   31    2600   6
CASTLEGAR    SPOK     19   20     750   4     37   27    1050   5
CRANBROOK    SPOK      9   19     950  11    100   28    3950   7
REVELSTOKE   KEL       9   17     500   0     29   24    1200   3

*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   SE  19   S   26
CRANBROOK             VR   5   S   15

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1700 m         28 C
SPOKANE         1100 m         28 C

TODAY'S VENTING: Becoming good in most valleys by mid afternoon.
Only fair to poor in the Columbias and the Kootenays due to
temperatures not breaking the low level inversion.

VENTING FOR MONDAY: fair.

VENTING OUTLOOK TUESDAY THRU THURSDAY: Fair until Wednesday
as the ridge remains over the region. Becoming good on Thursday
as a cold front sweeps through.

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   16     950   9    100   25    3950   9
PR. GEORGE   P.G.     24   16     850   9    100   23    3700   9
SMITHERS     P.G.     18   15     650   8     39   20     950   8
WELLS GRAY   P.G.      9   17    1000   9    100   25    4000   9
FT NLSN      F.N.     19   16     500   8     69   23    1500   8
FT STJOHN    F.N.      9   15     700   8    100   22    3700   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
PR. GEORGE            S   19   S   33
SMITHERS              SE  17   S   33

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1000 m         21 C
FT. NELSON       800 m         21 C

TODAY'S VENTING: Becoming good in the afternoon except poor
in the northwest.

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY: Fair until Wednesday
as the ridge remains over the region. Becoming good on Thursday
as a cold front sweeps through.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     14   19     450   2     70   24    1300   7
FRASER VLY   QUIL     14   19     400   2     87   26    1650   8
SRN VRISL    QUIL     12   18     300   1     47   23     950   5
CNTRL VRISL  QUIL     13   19     350   1     45   22     850   4
NRN VRISL    HRDY     14   16     150   3     17   18     300   3
TERRACE      ANT      10   15     250  19    100   18    1250  19
STEWART      ANT      13   16      50   6     42   18     650   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
VANCOUVER    VR   5   S   22   S   44
PORT HARDY   S   22   S   33   S   46
SANDSPIT     S   19   SE  26   SE  37

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1645 m         21 C
PORT HARDY       300 m         18 C
ANNETTE          none          none

TODAY'S VENTING: Becoming fair to good in the afternoon except
poor over northern Vancouver Island where cloud cover and showers
will keep temperatures from breaking the inversion.

VENTING FOR MONDAY: fair

VENTING OUTLOOK TUESDAY THRU THURSDAY:
Fair in the south until early Wednesday
as the ridge remains over the region. Becoming good late Wednesday
as a cold front sweeps through.

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

END/lm