FPCN39 CWLW 291434
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 Friday 29 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       9   17     500   5     80   21    2550  15
KAMLOOPS     KEL       9   16     550   0     70   22    2600   8
OKANAGAN     KEL      12   17     650   1     70   22    2600   8
CASTLEGAR    SPOK     26   16     900   4     69   20    2600   8
CRANBROOK    SPOK     31   15    1350   6    100   21    2650  11
REVELSTOKE   KEL       9   14     500   0     62   17    2350   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   11   W   22
CRANBROOK             W   11   W   31

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          800 m         17 C
SPOKANE         1000 m         15 C

TODAY'S VENTING: GOOD

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: 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.     10   10     950  19    100   18    3150  10
PR. GEORGE   P.G.     37   12    1000  11    100   16    2400  10
SMITHERS     P.G.     14   12     750   2    100   17    2300  10
WELLS GRAY   P.G.    100   12    2200  21    100   18    3000  12
FT NLSN      F.N.     76   12     800  24    100   14    2250  15
FT STJOHN    F.N.     98   12    1450  21    100   16    2150  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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   22   W   24
SMITHERS              W   17   NW  24

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       800 m         12 C
FT. NELSON      NO INVERSION

TODAY'S VENTING: GOOD

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     20   18     650   2     49   21    1550   5
FRASER VLY   QUIL     20   18     600   2     44   22    1700   5
SRN VRISL    QUIL     17   17     300   3     44   20    1550   5
CNTRL VRISL  QUIL     17   17     300   3     45   20    1500   5
NRN VRISL    HRDY     14   15     250   2     43   18    1500   5
TERRACE      ANT       9   14     200   2     46   19    1600   5
STEWART      ANT      15   15     150   5     49   19    1600   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   SW  11   SW  17
PORT HARDY   VR   5   VR   5   VR   5
SANDSPIT     NW  13   N   13   N   13

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       100 m         15 C
PORT HARDY       300 m         15 C
ANNETTE          400 m         16 C

TODAY'S VENTING: FAIR TO GOOD

VENTING FOR SATURDAY: FAIR TO GOOD

VENTING OUTLOOK SUNDAY THRU TUESDAY: FAIR TO GOOD




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

END/JMS