FPCN39 CWLW 221442
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 22 JULY 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   SPOK      9   23     200   3    100   36    3200   8
KAMLOOPS     SPOK     22   23     800   3    100   37    3350   8
OKANAGAN     SPOK      9   21     350   3    100   33    3350   8
CASTLEGAR    SPOK     19   22     800   4    100   34    3500   8
CRANBROOK    SPOK      9   19     950  10    100   30    3950  10
REVELSTOKE   SPOK      9   20     450   3     50   30    1300   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: FAIR

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   16     950   9     99   27    3950   6
PR. GEORGE   P.G.     14   16     850   4     99   26    3700   6
SMITHERS     P.G.      9   17     800   0     99   26    3500   6
WELLS GRAY   P.G.     29   19    1250   9     99   30    4000   6
FT NLSN      F.N.      9   16     500   0      9   24    1250   0
FT STJOHN    F.N.      9   16     700   0      9   23    3700   0

*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            VR   5   N   12
SMITHERS              SW  13   SW  20

TODAY'S VENTING: POOR

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     17   20     350   3     21   25     500   3
FRASER VLY   QUIL     19   22     400   3     33   30     950   3
SRN VRISL    QUIL      9   18     300   0      9   24     450   0
CNTRL VRISL  QUIL      9   22     400   0     45   33    1950   2
NRN VRISL    HRDY     33   15     250  12     58   20     650  10
TERRACE      ANT      42   19    1000   5    100   28    2850  11
STEWART      ANT      35   19     650   5    100   28    2300   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    VR   5   VR   5   VR   5
PORT HARDY   N   20   VR   5   W    9
SANDSPIT     W   13   SW  20   SW  31

TODAY'S VENTING: POOR

VENTING FOR THURSDAY: GOOD

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

END/MWSO