FPCN39 CWLW 231338
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 7:00 AM PDT SUNDAY 23 AUGUST 1998 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       9   22     550   0     50   29    1600   5
KAMLOOPS     KEL       9   20     550   0     57   27    1450   6
OKANAGAN     KEL       9   19     500   0     55   29    2350   3
CASTLEGAR    SPOK      9   19     750   0     40   27    1650   5
CRANBROOK    SPOK      9   16     950   2    100   24    3950   6
REVELSTOKE   KEL       9   18     500   0     40   25    1350   4

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   NW  13   N   19
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1300 m         24 C
SPOKANE         1100 m         25 C

TODAY'S VENTING: GOOD.

VENTING FOR MONDAY: GOOD.

VENTING OUTLOOK TUESDAY THRU THURSDAY: GOOD.


CENTRAL INTERIOR/NORTHEAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
WILLIAMS L   P.G.     12   14    1000  15     89   25    3950  14
PR. GEORGE   P.G.     10   13     800   9     90   23    3700  12
SMITHERS     P.G.     10   12     650   7     91   20    1950  10
WELLS GRAY   P.G.     10   12    1200  14     89   21    4000  14
FT NLSN      F.N.      9   15     400  24    100   21    2850  28
FT STJOHN    F.N.    100   17    2050  26    100   22    3700  28

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   19   W   19
SMITHERS              W   13   NW  19

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1000 m         17 C
FT. NELSON       700 m         16 C

TODAY'S VENTING: GOOD.

VENTING FOR MONDAY: GOOD.

VENTING OUTLOOK TUESDAY THRU THURSDAY: GOOD.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     29   19     750   3     54   23    1650   4
FRASER VLY   QUIL     27   18     700   3     72   25    2200   4
SRN VRISL    QUIL     20   19     750   2     47   23    1550   3
CNTRL VRISL  QUIL     19   18     700   2     68   25    2200   4
NRN VRISL    HRDY     76   16     850  12     91   18    1100  13
TERRACE      ANT      56   17    1300   5     89   21    2450   6
STEWART      ANT      44   17     850   5     80   21    2000   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   15   W   13   W   13
PORT HARDY   NW  30   NW  22   NW  19
SANDSPIT     NW  19   NW  15   NW  19

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1100 m         21 C
PORT HARDY      1300 m         21 C
ANNETTE          300 m         13 C

TODAY'S VENTING: GOOD.

VENTING FOR MONDAY: GOOD.

VENTING OUTLOOK TUESDAY THRU THURSDAY: GOOD.


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


END/MWSO