FPCN39 CWLW 251404
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 FRIDAY 25 SEPTEMBER 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   KEL      12   14     450   1     60   18     900   2
KAMLOOPS     KEL      11   15     550   1     67   19    1900   5
OKANAGAN     KEL      10   13     500   1     56   16     800   2
CASTLEGAR    SPOK     44   14     850  11     69   17    1300  10
CRANBROOK    SPOK      9   12     950  10     85   15    2000  12
REVELSTOKE   KEL      10   13     500   1     14   15     750   2

*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    N   15   N   30   N   50
CRANBROOK             VR   5   N   20

TODAY'S VENTING: GOOD EXCEPT POOR IN THE COLUMBIA VALLEY.

VENTING FOR SATURDAY: POOR




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.     79    9    1350  27    100   14    3950  21
PR. GEORGE   P.G.     23    9     800  13    100   13    1800  20
SMITHERS     P.G.      9    9     500   8    100   14    1500  20
WELLS GRAY   P.G.    100   10    1800  27    100   14    4000  21
FT NLSN      F.N.    100    8    1200  22    100   13    2100  20
FT STJOHN    F.N.    100    9    1950  20    100   12    2350  20

*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
SMITHERS              NW  15   N

TODAY'S VENTING: GOOD




VENTING FOR SATURDAY: POOR




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     63   14     650  12     89   16    1150  13
FRASER VLY   QUIL     88   16    1100  13    100   20    1450  13
SRN VRISL    QUIL     68   15     750  11     93   18    1300  12
CNTRL VRISL  QUIL     20   13     250   5     93   18    1300  12
NRN VRISL    HRDY      9   12       0  12    100   15    1150  25
TERRACE      ANT     100   12    1050  22    100   16    1450  22
STEWART      ANT      56   12     450  13    100   16    1300  18

*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    N   26   N   31   NE  43
PORT HARDY   N   33   N   39   N   56
SANDSPIT     NW  30   N   39   N   63

TODAY'S VENTING: GOOD




VENTING FOR SATURDAY: POOR




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


END/