FPCN39 CWLW 051431 AAA
REVISED SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR
INCLUDING THE NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE
OF ENVIRONMENT CANADA AT 7.28 AM PDT WEDNESDAY 5 AUGUST 1998 FOR
TODAY.

*** correction to interior Vancouver Island index ***

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   21     200   2     24   32     650   4
KAMLOOPS     KEL      12   24     450   2    100   38    3350  17
OKANAGAN     KEL      12   25     500   2    100   38    3350  17
CASTLEGAR    SPOK     20   25     800   4     51   35    1100   9
CRANBROOK    SPOK     ##   ##     ###  ##     70   33    1400  18
REVELSTOKE   KEL      10   24     500   2     47   35    1400   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
PENTICTON    SW   9   SW  24   SW  43
CRANBROOK             SW  13   SW  39

TODAY'S VENTING:




VENTING FOR THURSDAY: 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   17     950   4    100   31    3950  17
PR. GEORGE   P.G.      9   16     700   1     71   26    1900   7
SMITHERS     P.G.      9   15     500   1     16   21     800   3
WELLS GRAY   P.G.      9   18    1000   4    100   30    4000  17
FT NLSN      F.N.     11   16     600   1     82   24    2250   6
FT STJOHN    F.N.     20   17     900   6    100   25    3700   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              W   17   W

TODAY'S VENTING:




VENTING FOR THURSDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     92   16     550  15    100   22     900  15
FRASER VLY   QUIL    100   19     800  15    100   26    1100  15
SRN VRISL    QUIL      9   15     350   0     41   22     900   5
CNTRL VRISL  QUIL      9   16     500   0     45   26    1050   5
NRN VRISL    HRDY      9   15       0   1     17   18     550   2
TERRACE      ANT       9   14     200  12     83   20    2000   7
STEWART      ANT      15   16     150   5     56   20     800   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    SW  19   SW  24   SW  43
PORT HARDY   W   19   W   19   W   28
SANDSPIT     NW  20   W   19   W   22

TODAY'S VENTING:




VENTING FOR THURSDAY: GOOD




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


END/