FPCN39 CWLW 241431
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 8:00 AM PDT Sunday 24 August 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      24   18     700   3     87   25    2850  14
KAMLOOPS     KEL      40   18    1100   5     66   27    2700   5
OKANAGAN     KEL      40   18    1100   5     70   28    3350   7
CASTLEGAR    SPOK      9   20     500   4     58   26    3300   7
CRANBROOK    SPOK      9   20     950   6     79   27    3950   6
REVELSTOKE   KEL      26   16     900   4     59   20    2500   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  11   SW  17
CRANBROOK             W    9   W   24

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1500 m         20 C
SPOKANE          800 m         23 C

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU 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   13     950  13    100   21    3950   7
PR. GEORGE   P.G.     45   13     950  15     92   20    2300   9
SMITHERS     P.G.     49   15    1000  10     74   19    2250   8
WELLS GRAY   P.G.     45   14    1300  13    100   21    4000   7
FT NLSN      F.N.      9   16     400   5     89   23    2200  12
FT STJOHN    F.N.     12   15     750   6     63   20    2750   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   22   SW  30
SMITHERS              S   28   S   30

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1600 m         20 C
FT. NELSON      1000 m         20 C

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     39   17     400  11     58   20    1850  10
FRASER VLY   QUIL     37   17     350  11     58   21    1800  10
SRN VRISL    QUIL     20   16     250   5     89   21    1850  10
CNTRL VRISL  QUIL     31   17     300   9     80   20    1950  10
NRN VRISL    HRDY     19   16     150   7     75   18    1850  10
TERRACE      ANT      97   15     700  34    100   18    2350  15
STEWART      ANT      77   16     450  23    100   18    2300  15

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   31   S   43   S   44
PORT HARDY   S   33   S   44   S   52
SANDSPIT     S   44   S   46   S   50

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1400 m         20 C
PORT HARDY       400 m         18 C
ANNETTE         NO INVERSION

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY: GOOD




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

END/JMS