FPCN39 CWLW 161435
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 16 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      17   20     600   2    100   26    2750  13
KAMLOOPS     KEL      13   18     550   2    100   26    3350  14
OKANAGAN     KEL      13   18     550   2    100   27    3350  14
CASTLEGAR    SPOK     16   17     750   3    100   26    3500  11
CRANBROOK    SPOK      9   16     950   8    100   24    3950  14
REVELSTOKE   KEL      10   15     500   2    100   24    3450  14


*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    W   11   W   22   W   30
CRANBROOK             W    9   W   26

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          880 m         20 C
SPOKANE          825 m         22 C

TODAY'S VENTING: BECOMING GOOD 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.    100   14    3950  19    100   20    3950  19
PR. GEORGE   P.G.     13   13     850   3    100   18    3700  15
SMITHERS     P.G.     15   14     800   2    100   21    3500  14
WELLS GRAY   P.G.    100   15    4000  19    100   20    4000  19
FT NLSN      F.N.     15   11     450   8     41   14     850   8
FT STJOHN    F.N.     31   14    1050   7     71   17    1950   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            W   41   W   50
SMITHERS              W   30   W   50

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       944 m         17 C
FT. NELSON      1097 m         18 C

TODAY'S VENTING: BECOMING GOOD THIS AFTERNOON EXCEPT BECOMING FAIR
OVER NORTHERN SECTIONS OF THE NORTHEAST.

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     19   17     450   3     64   21    1300   6
FRASER VLY   QUIL     19   17     400   3     79   23    1750   6
SRN VRISL    QUIL     17   16     300   3     50   19     950   4
CNTRL VRISL  QUIL     15   15     250   3     60   17    1400   3
NRN VRISL    HRDY      9   13       0   6     91   15    2438   7
TERRACE      ANT     100   11    2050  11    100   15    2400  11
STEWART      ANT     100   13    2050  10    100   15    2200  10


*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    W   20   W   28   W   43
PORT HARDY   W   20   W   31   W   46
SANDSPIT     NW  31   NW  39   NW  52

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       700 m         19 C
PORT HARDY       395 m         16 C
ANNETTE         NO INVERSION

TODAY'S VENTING: GOOD THIS AFTERNOON EXCEPT FAIR OVER SOUTHERN
VANCOUVER ISLAND THIS AFTERNOON.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: GOOD IN THE AFTERNOONS IN
THE SOUTH. FAIR SUNDAY IN THE NORTH THEN GOOD FOR MONDAY AND TUESDAY
AFTERNOONS.

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

END/plj