FPCN39 CWLW 051430
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 Tuesday 5 August 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      22   27     700   3     48   35    1700   3
KAMLOOPS     KEL      17   25     650   3     51   34    1900   3
OKANAGAN     KEL      17   25     650   3     51   34    1900   3
CASTLEGAR    SPOK     24   25     750   6    100   35    3500   8
CRANBROOK    SPOK      9   24     950  16    100   32    3950   7
REVELSTOKE   KEL       9   22     550   0     32   31    1400   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1500 m         36 C
SPOKANE         1300 m         31 C

TODAY'S VENTING: fair.

VENTING FOR WEDNESDAY: fair.

VENTING OUTLOOK THURSDAY THRU SATURDAY: generally fair.


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   19     950   8    100   29    3950  19
PR. GEORGE   P.G.     16   19     900   4     43   27    1400   6
SMITHERS     P.G.     10   18     700   1     22   24    1050   3
WELLS GRAY   P.G.      9   19    1000   8    100   29    4000  19
FT NLSN      F.N.     18   19     450  10     73   26    1300  10
FT STJOHN    F.N.      9   20     700  10    100   26    2700   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            VR   5   S   24
SMITHERS              VR   5   S   24

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1600 m         31 C
FT. NELSON       700 m         25 C

TODAY'S VENTING:  fair to good.

VENTING FOR WEDNESDAY: good.

VENTING OUTLOOK THURSDAY THRU SATURDAY: decreasing to fair thru the
period.



COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     63   20     950   8     54   24    1000   8
FRASER VLY   QUIL     64   21     950   8     66   30    2050   9
SRN VRISL    QUIL     61   21     950   8     54   25    1000   8
CNTRL VRISL  QUIL     62   23     950   8     54   29    1350   8
NRN VRISL    HRDY      9   16       0   7     74   21    1000  10
TERRACE      ANT      43   20    1250   4    100   25    2700   9
STEWART      ANT       9   18     150   0     94   25    2150   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   VR   5   S   19
PORT HARDY   NW   9   S   17   S   28
SANDSPIT     S   11   S   20   S   30

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1400 m         29 C
PORT HARDY       700 m         20 C
ANNETTE          200 m         19 C

TODAY'S VENTING: generally fair.

VENTING FOR WEDNESDAY: good.

VENTING OUTLOOK THURSDAY THRU SATURDAY: deceasing to fair.

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

END/dsl