FPCN39 CWLW 041432
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 4 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      15   22     750   1     76   31    3200   3
KAMLOOPS     KEL      16   22    1000   1     76   30    3350   3
OKANAGAN     KEL      14   21     850   1     76   30    3350   3
CASTLEGAR    KEL      27   19     950   4     71   27    2050   6
CRANBROOK    KEL       9   19     950   8    100   26    3950   6
REVELSTOKE   KEL      10   18     600   1     76   26    3450   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW   9   W   17
CRANBROOK             VR   5   W   11

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1600 m         24 C
SPOKANE         NOT AVAILABLE

TODAY'S VENTING: GOOD

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: 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.     78   19    3950   4     78   25    3950   4
PR. GEORGE   P.G.     15   15     850   4     80   24    3700   4
SMITHERS     P.G.     16   15     800   3     77   23    3500   3
WELLS GRAY   P.G.      9   17    1000   3     78   26    4000   4
FT NLSN      F.N.     51   19    1100   7     85   24    2200   7
FT STJOHN    F.N.     41   17    1400   5    100   24    3700   8

*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            VR   5   SW  13
SMITHERS              SE  13   S   13

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       900 m         21 C
FT. NELSON       600 m         16 C

TODAY'S VENTING: GOOD

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     12   19     150   3     22   23     400   4
FRASER VLY   QUIL     15   22     250   3     29   28     850   3
SRN VRISL    QUIL     13   18     150   3     27   25     600   3
CNTRL VRISL  QUIL     13   19     150   3     29   26     650   3
NRN VRISL    HRDY     18   15     250   4     29   19     450   5
TERRACE      ANT      30   18     500   9     98   24    2300   8
STEWART      ANT      21   17     200   7     93   24    2050   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
VANCOUVER    S    9   S   17   S   20
PORT HARDY   S   19   S   41   S   50
SANDSPIT     SE  11   SE  35   SE  54

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       900 m         27 C
PORT HARDY      1200 m         27 C
ANNETTE          600 m         20 C

TODAY'S VENTING: POOR EXCEPT GOOD ON THE NORTH COAST.

VENTING FOR SATURDAY: FAIR

VENTING OUTLOOK SUNDAY THRU TUESDAY: GOOD.



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

END/JMS