FPCN39 CWLW 281425
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 PST THURSDAY 28 JANUARY 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       9    3     450   0    100    4    2000  18
KAMLOOPS     KEL       9    0     350   0    100    3    2000  12
OKANAGAN     KEL       9    1     350   0    100    3    2000  12
CASTLEGAR    SPOK      9   -1     500  16      5    0     600   5
CRANBROOK    SPOK      9   -2     950  54     70   -1    1450  12
REVELSTOKE   KEL       9   -1     450   0      5    0     450   3

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    S    9   SW  30   SW  76
CRANBROOK             SW  20   SW  57

TODAY'S VENTING: GOOD IN THE WEST. POOR IN THE EAST.

VENTING FOR FRIDAY: FAIR.

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   -4     950  18    100    1    3950  15
PR. GEORGE   P.G.     55   -1     950  21     50   -1     950  12
SMITHERS     P.G.      9   -7     500   3      2   -4     650   2
WELLS GRAY   P.G.     10   -7     800   3    100   -1    4000  15
FT NLSN      F.N.     30  -19     750   6     50  -18     950   9
FT STJOHN    F.N.     96  -16    1400  23     70  -14    1500  10

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  35   SW  46
SMITHERS              SW  19   SW  46

TODAY'S VENTING: VARIABLE.

VENTING FOR FRIDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     63    6     650  13     80    7    1200  16
FRASER VLY   QUIL      9    4      50   3     70    6    1000  10
SRN VRISL    QUIL     72    7     800  12    100   10    1700  16
CNTRL VRISL  QUIL      9    2      50   0     80    6    1000  12
NRN VRISL    HRDY     33    2     350   9    100    5    1550  12
TERRACE      ANT      10    0     200  16    100    0    2000  16
STEWART      ANT      90   -1    1500   8    100    0    2000   8

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   48   S   76   SW  89
PORT HARDY   SE  22   S   39   S   56
SANDSPIT     S   24   S   30   S   33

TODAY'S VENTING: GOOD.

VENTING FOR FRIDAY: FAIR.

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

END/KJ