FPCN39 CWLW 121432
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 Monday 12 May 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      23   19     900   2     83   30    2100   6
KAMLOOPS     KEL      19   17     850   2     63   27    1800   5
OKANAGAN     KEL      17   15     600   3     63   27    1800   5
CASTLEGAR    SPOK     19   15     750   4     39   25    1800   3
CRANBROOK    SPOK      9   15     950   2     64   25    2700   4
REVELSTOKE   KEL      14   14     600   3     57   25    1700   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   19   W   33
CRANBROOK             W   13   W   37

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1890 m         25 C
SPOKANE         1125 m         22 C

TODAY'S VENTING: GOOD THIS AFTERNOON.

VENTING FOR TUESDAY: GOOD

VENTING OUTLOOK WEDNESDAY THROUGH FRIDAY: FAIR IN THE AFTERNOONS.

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   14     950  18    100   23    3950  19
PR. GEORGE   P.G.     26   14     900   9    100   23    2550  16
SMITHERS     P.G.     22   14     800   5    100   23    2300  14
WELLS GRAY   P.G.      9   14    1000  18    100   25    4000  19
FT NLSN      F.N.    100   16    2200  50    100   19    3400  50
FT STJOHN    F.N.    100   17    3700  51    100   20    3700  51


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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   24   NW  33
SMITHERS              NW  11   NW  33

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1430 m         20 C
FT. NELSON      NO INVERSION

TODAY'S VENTING: GOOD IN THE AFTERNOON.

VENTING FOR TUESDAY: GOOD

VENTING OUTLOOK WEDNESDAY THROUGH FRIDAY: FAIR TO GOOD IN THE
AFTERNOONS.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     13   16     200   3     35   23     650   3
FRASER VLY   QUIL     15   22     250   3     45   30    1350   3
SRN VRISL    QUIL     15   18     200   3     27   27     550   4
CNTRL VRISL  QUIL     15   18     200   3     32   29     800   3
NRN VRISL    HRDY     17   13     150   6     38   20     400   9
TERRACE      ANT       9   15     200   4    100   25    2500  11
STEWART      ANT      17   15     200   4    100   25    2200   9


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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   W   11   W   24
PORT HARDY   VR   5   VR   5   SW  15
SANDSPIT     N   24   N   17   NW  13

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       730 m         27 C
PORT HARDY      1310 m         26 C
ANNETTE          400 m         18 C

TODAY'S VENTING: POOR TO FAIR IN THE SOUTH. GOOD THIS AFTERNOON IN
THE NORTH.

VENTING FOR TUESDAY: FAIR.

VENTING OUTLOOK WEDNESDAY THROUGH FRIDAY: FAIR TO GOOD IN THE
AFTERNOON.

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

END/PLJ