FPCN39 CWLW 301432
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 Wednesday 30 July 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     850   0    100   26    3200   6
KAMLOOPS     KEL      20   22    1300   1    100   25    3350   6
OKANAGAN     KEL       9   20     350   0    100   23    3350   6
CASTLEGAR    SPOK     37   20     950   7     76   24    1800   8
CRANBROOK    SPOK     81   21    2100  10    100   25    3950  14
REVELSTOKE   KEL       9   18     450   0     19   21    1300   1

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  13   SW  22
CRANBROOK             W   13   W   33

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          800 m         19 C
SPOKANE         1100 m         19 C

TODAY'S VENTING: generally good.

VENTING FOR THURSDAY: generally good.

VENTING OUTLOOK FRIDAY THRU SUNDAY: 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.    100   20    1450  15    100   23    1900  18
PR. GEORGE   P.G.    100   20    1450  15    100   25    1800  24
SMITHERS     P.G.      9   15     500   2    100   22    1550  21
WELLS GRAY   P.G.     86   19    1650  15    100   24    4000  15
FT NLSN      F.N.     44   15    1000   7     60   20    1450   6
FT STJOHN    F.N.     41   16    1350   6     68   20    2100   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   22   SW  28
SMITHERS              SW  17   SW  28

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      2000 m         28 C
FT. NELSON      1500 m         23 C

TODAY'S VENTING: good.

VENTING FOR THURSDAY: good.

VENTING OUTLOOK FRIDAY THRU SUNDAY: good.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     72   18    1150   8     95   22    1700  10
FRASER VLY   QUIL     72   18    1150   8     99   23    1800  10
SRN VRISL    QUIL     50   17     850   6     89   22    1650   8
CNTRL VRISL  QUIL     64   18    1100   7     89   22    1650   8
NRN VRISL    HRDY      9   14      50   2     54   18    1300   4
TERRACE      ANT      95   16    1550  12    100   21    3200  14
STEWART      ANT      55   16     800   8    100   21    2500  11

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   13   W   15   SW  22
PORT HARDY   W   11   SW  17   SW  24
SANDSPIT     S   24   S   28   S   30

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       200 m         14 C
PORT HARDY       200 m         15 C
ANNETTE          none.

TODAY'S VENTING: good.

VENTING FOR THURSDAY: good.

VENTING OUTLOOK FRIDAY THRU SUNDAY: good.


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

END/dsl