FPCN39 CWLW 121400
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 MONDAY 12 APRIL 1999 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     100   13    1500  20    100   15    1650  20
KAMLOOPS     KEL     100   14    1500  20    100   16    2000  15
OKANAGAN     KEL      70   12    1350  15    100   14    1800  15
CASTLEGAR    SPOK     23    8     800   8     70   13    1500  15
CRANBROOK    SPOK      9    6     950  17    100   13    2000  20
REVELSTOKE   KEL       9    6     450   5     40    9     850  12

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W   13   W   33   W   65
CRANBROOK             SW  24   SW  67

TODAY'S VENTING: GOOD EXCEPT FAIR REVELSTOKE AREA.

VENTING FOR 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.      9    7     850  23    100    9    3000  20
PR. GEORGE   P.G.      9    6     700  22    100    8    3000  20
SMITHERS     P.G.      9    3     500   2     80    7    2650  10
WELLS GRAY   P.G.      9    2     900   8    100    9    3000  20
FT NLSN      F.N.      9    2     400  10    100    9    2700  15
FT STJOHN    F.N.      9    5     700  18    100    8    3200  19

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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   48   W   61
SMITHERS              W   39   W   61

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: GOOD.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL    100   10    1300  21    100   12    1500  24
FRASER VLY   QUIL    100   10    1300  21    100   12    1450  21
SRN VRISL    QUIL    100   10    1100  16    100   13    1550  24
CNTRL VRISL  QUIL     65    9     700  12    100   13    1550  24
NRN VRISL    HRDY     51    7     550   9     90    9    1150  13
TERRACE      ANT      83    4     850  18    100    7    1650  22
STEWART      ANT      48    4     400  12    100    7    1050  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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  30   W   46   W   61
PORT HARDY   W   33   W   43   W   39
SANDSPIT     W   46   W   56   W   59

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: FAIR.

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


END/KAL
$$$$^^