FPCN39 CWLW 211332
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 MONDAY 21 SEPTEMBER 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      28   16     850   3     88   25    2400   6
KAMLOOPS     KEL      23   14     850   3     69   23    1900   5
OKANAGAN     KEL      16   13     700   2    100   24    3350   7
CASTLEGAR    SPOK     22   14     750   5     82   27    1750   9
CRANBROOK    SPOK      9   13     950   9     75   21    2300   9
REVELSTOKE   KEL      20   12     800   3     60   21    1650   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   N   15   N   19
CRANBROOK             VR   5   N    9

TODAY'S VENTING: GOOD.

VENTING FOR 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.      9    9     950  11     91   18    2150  12
PR. GEORGE   P.G.     14    8     800   4     40   16    1050   8
SMITHERS     P.G.      9    8     700   2     58   14    1350   8
WELLS GRAY   P.G.      9   10    1000  11     95   18    2300  12
FT NLSN      F.N.      9   12     400  20    100   23    2350  38
FT STJOHN    F.N.      9   11     700  29    100   21    2550  40

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            NW  15   NW
SMITHERS              NW  15   NW

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     14   14     250   3     33   19     550   6
FRASER VLY   QUIL     16   15     300   3     52   24    1500   4
SRN VRISL    QUIL     12   13     200   2     26   19     500   4
CNTRL VRISL  QUIL     13   15     250   2     33   22     750   4
NRN VRISL    HRDY     24   13     350   5     62   17    1000   7
TERRACE      ANT      10   12     250  11     85   18    1950   7
STEWART      ANT      53   14     600   9     85   18    1700   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    NW  13   N   13   N   13
PORT HARDY   N   17   N   15   N   11
SANDSPIT     N   37   N   30   NW  28

TODAY'S VENTING: FAIR OVER THE SOUTH COAST BECOMING GOOD OVER
 SECTIONS OF THE NORTH COAST.

VENTING FOR TUESDAY: FAIR.

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


END/MWSO