FPCN39 CWLW 071328
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 7 AUGUST 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      50   21     550  15    100   31    3200  20
KAMLOOPS     KEL      15   19     550   3     89   31    3350   5
OKANAGAN     KEL      15   19     550   3     89   31    3350   5
CASTLEGAR    SPOK     31   19     800   8    100   30    3500   8
CRANBROOK    SPOK      9   15     950   6    100   27    3950   8
REVELSTOKE   KEL      12   18     550   3     89   29    3450   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
PENTICTON    VR   5   W   11   W   15
CRANBROOK             VR   5   W   13

TODAY'S VENTING: GOOD.

VENTING FOR SATURDAY: 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.    100   14    2100  22    100   24    3950  24
PR. GEORGE   P.G.    100   15    1850  16    100   22    3700  20
SMITHERS     P.G.      9   12     550   2    100   18    2050  16
WELLS GRAY   P.G.    100   16    2450  24    100   25    4000  24
FT NLSN      F.N.      9   15     400  29    100   23    3400  33
FT STJOHN    F.N.      9   12     700  33    100   21    3700  33

*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              SW  26   SW

TODAY'S VENTING: GOOD.

VENTING FOR SATURDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     82   17     950  13     97   23    1250  14
FRASER VLY   QUIL     83   17     950  13    100   25    1500  14
SRN VRISL    QUIL     55   16     900   7     78   23    1200   9
CNTRL VRISL  QUIL     55   16     900   7     92   25    1450  10
NRN VRISL    HRDY      9   14       0   6     62   18    1150   6
TERRACE      ANT      10   12     250  13    100   17    1550  16
STEWART      ANT      17   13     150   7     83   17    1100  11

*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    W   15   W   15   W   19
PORT HARDY   SW  17   S   24   SW  28
SANDSPIT     S   48   SW  52   SW  56

TODAY'S VENTING: GOOD.

VENTING FOR SATURDAY: GOOD




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


END/MWSO