FPCN39 CWLW 231325
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 WEDNESDAY 23 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       9   14     500   0     25   23    1250   2
KAMLOOPS     KEL       9   14     550   0     25   24    1700   2
OKANAGAN     KEL       9   13     550   0     30   23    1500   2
CASTLEGAR    SPOK     17   14     750   3     30   22    1050   4
CRANBROOK    SPOK      9   13     950   5    100   21    3950   6
REVELSTOKE   KEL       9   14     550   0     25   21    1350   2

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   17   W   26
CRANBROOK             W   13   W   28

TODAY'S VENTING: POOR.

VENTING FOR THURSDAY: 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    9     950   8     75   19    2000   5
PR. GEORGE   P.G.      9    9     700   1     40   16    1200   5
SMITHERS     P.G.     11    7     700   1     35   14     950   5
WELLS GRAY   P.G.      9    9    1000   8     85   19    2550  10
FT NLSN      F.N.     19   10     550   6     25   13     700   5
FT STJOHN    F.N.      9    9     700   4     45   16    1350   5

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              W   37   W

TODAY'S VENTING:  FAIR.

VENTING FOR THURSDAY: FAIR.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     10   14     200   1     15   19     450   3
FRASER VLY   QUIL     10   15     200   1     25   23     650   3
SRN VRISL    QUIL     10   14     200   1     15   21     550   3
CNTRL VRISL  QUIL     10   16     200   1     25   22     600   3
NRN VRISL    QUIL     10   13     150   1     15   16     200   3
TERRACE      ANT       9   12     200  10     50   16     750  10
STEWART      ANT      37   14     400   8     45   16     600   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W    9   NW  11   NW  17
PORT HARDY   N   31   N   39   NW  39
SANDSPIT     W   46   W   57   W   57

TODAY'S VENTING: POOR SOUTH FAIR NORTH.

VENTING FOR THURSDAY: POOR

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

END/