FPCN39 CWLW 231434
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 23 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      42   15    1000   5    100   22    3200   7
KAMLOOPS     KEL      40   14    1150   5    100   20    3350   7
OKANAGAN     KEL      34   13     950   5     74   19    1950   6
CASTLEGAR    SPOK      9   13     500   8     78   19    2100   7
CRANBROOK    SPOK      9   11     950   5    100   17    3950  12
REVELSTOKE   KEL      30   12     950   5     68   17    1800   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   S    9
CRANBROOK             VR   5   S   13

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         NO INVERSION
SPOKANE          760 m         16 C

TODAY'S VENTING: BECOMING GOOD LATE THIS AFTERNOON.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: GOOD 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.     90   10    2450   9    100   14    3950  11
PR. GEORGE   P.G.     11    7    1000   1    100   16    3700   8
SMITHERS     P.G.     11    9    1000   0    100   17    2900   8
WELLS GRAY   P.G.     72    8    2100   8    100   15    4000  11
FT NLSN      F.N.     38   14     800   8    100   23    3400   7
FT STJOHN    F.N.      9    7     700   7     50   12    1600   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            N   11   VR   5
SMITHERS              VR   5   N    5

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1125 m         11 C
FT. NELSON       850 m         14 C

TODAY'S VENTING: GOOD THIS AFTERNOON EXCEPT FAIR OVER THE SOUTHERN
PEACE.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: 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     24   13     750   2     66   17    2650   3
FRASER VLY   QUIL     44   15    1450   3     67   19    2750   3
SRN VRISL    QUIL     29   14     850   3     67   18    2700   3
CNTRL VRISL  QUIL     24   13     600   3     61   17    2400   3
NRN VRISL    HRDY      9   11     150   0     85   16    2150   3
TERRACE      ANT       9   13     200   8    100   22    3200   8
STEWART      ANT      18   14     150   6     72   22    1550   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   VR   5   VR   5
PORT HARDY   NW  13   NE   9   NE  20
SANDSPIT     NW  22   N   26   N   31

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       250 m         12 C
PORT HARDY       150 m         12 C
ANNETTE          335 m         18 C

TODAY'S VENTING: GOOD.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: GOOD SUNDAY AND MONDAY
AFTERNOONS. FAIR TUESDAY AFTERNOON.


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

END/PLJ