FPCN39 CWLW 181356
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 SATURDAY 18 OCTOBER 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      20   10     500   4     91   15    2000   8
KAMLOOPS     KEL      20   10     550   8    100   15    2500   9
OKANAGAN     KEL      10    9     500   5    100   15    2500   9
CASTLEGAR    SPOK     30   10     850   7     41   14    1000   7
CRANBROOK    SPOK      9    9     950  12    100   15    3950  11
REVELSTOKE   KEL       9    8     500   0     49   11    1250   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   W   11

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          500 m         10 C
SPOKANE          950 m         12 C

TODAY'S VENTING: Good.

VENTING FOR SUNDAY: Fair.

VENTING OUTLOOK MONDAY THRU WEDNESDAY: 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    2     950  14    100   10    3950  13
PR. GEORGE   P.G.     23    3     850  10    100    9    2250  12
SMITHERS     P.G.      9    3     750   0     65    9    1400   9
WELLS GRAY   P.G.     10    4    1000  14    100   10    4000  13
FT NLSN      F.N.     21   -2     500  10     25    2     550  10
FT STJOHN    F.N.      9    4     700   9     71    8    1650   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  19   W   30
SMITHERS              W   30   W   30

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1500 m         10 C
FT. NELSON      1200 m         12 C

TODAY'S VENTING: Good.

VENTING FOR SUNDAY: Good.

VENTING OUTLOOK MONDAY THRU WEDNESDAY: Fair to good.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     24   10     250   8     66   16    1600   5
FRASER VLY   QUIL     25   10     250   8     66   16    1600   5
SRN VRISL    QUIL     23   10     250   7     67   17    1600   5
CNTRL VRISL  QUIL     23   10     250   7     66   15    1550   5
NRN VRISL    HRDY     62   10     500  14    100   14    1200  19
TERRACE      ANT       9    7     250   7     96   11    1950   9
STEWART      ANT      10    8      50   2     56   11     900   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    NE  15   E   15   VR   5
PORT HARDY   N   15   N    9   W   13
SANDSPIT     W   24   W   26   W   28

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       300 m         13 C
PORT HARDY        70 m         10 C
ANNETTE          250 m         10 C

TODAY'S VENTING: Good.

VENTING FOR SUNDAY: Fair.

VENTING OUTLOOK MONDAY THRU WEDNESDAY: Fair.

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


END/DB