FPCN39 CWLW 241404
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 24 SEPTEMBER 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      19   18     700   2     28   28    1450   3
KAMLOOPS     KEL      16   17     700   2     22   26    1400   3
OKANAGAN     KEL      15   16     650   2     22   25    1300   3
CASTLEGAR    KEL       9   15     500   3     22   23    1300   3
CRANBROOK    KEL       9   14     950   3     31   23    1750   4
REVELSTOKE   KEL      13   14     600   2     16   20    1000   3

*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    SE   9   S   24   S   43
CRANBROOK             VR   5   S   20

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         2600 m         33 C
SPOKANE         MISSING

TODAY'S VENTING: POOR.

VENTING FOR THURSDAY: FAIR.

VENTING OUTLOOK FRIDAY THRU SUNDAY: 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   15     950  13     54   24    1650   7
PR. GEORGE   P.G.     18   15     800   8     54   24    1600   7
SMITHERS     P.G.      9   13     700   0     54   19    1600   4
WELLS GRAY   P.G.     10   14    1000  13     60   25    1700   8
FT NLSN      F.N.     29   14     500  17     50   22    1450   8
FT STJOHN    F.N.      9   17     700  18     50   22    1400   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
PR. GEORGE            S   37   S   46
SMITHERS              S   28   S   46

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      2300 m         27 C
FT. NELSON       700 m         20 C

TODAY'S VENTING: FAIR.

VENTING FOR THURSDAY: GOOD.

VENTING OUTLOOK FRIDAY THRU SUNDAY: GOOD.




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9   16     100   5     16   21     200   5
FRASER VLY   QUIL      9   19     150   0     18   28     400   3
SRN VRISL    QUIL      9   17     150   0      9   23     250   5
CNTRL VRISL  QUIL      9   18     150   0     14   26     350   2
NRN VRISL    HRDY     20   15     300   4     25   19     450   7
TERRACE      ANT      10   14     200  16     20   15     200  10
STEWART      ANT       9   13       0   5     19   15       0   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
VANCOUVER    SE  30   S   43   S   37
PORT HARDY   S   15   S   41   S   57
SANDSPIT     SW  13   SW  26   S   43

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       600 m         29 C
PORT HARDY      1500 m         30 C
ANNETTE         NO INVERSION

TODAY'S VENTING: POOR.

VENTING FOR THURSDAY: GOOD.

VENTING OUTLOOK FRIDAY THRU SUNDAY: GOOD.




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


END/JMS