FPCN39 CWLW 211355
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 21 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    2     200   0     25    4     500   5
KAMLOOPS     KEL       9    3     500   0     24    4     650   5
OKANAGAN     KEL       9    2     450   0     24    4     650   5
CASTLEGAR    SPOK     22    2     750   5     25    3     850   5
CRANBROOK    SPOK      9   -3     950   5     10   -2     950   7
REVELSTOKE   KEL       9    2     500   0     17    3     650   4

*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    SW  13   W   28   W   57
CRANBROOK             W   13   W   37

TODAY'S VENTING: POOR

VENTING FOR FRIDAY: 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.     25  -10    1250   5     30   -8    1400   5
PR. GEORGE   P.G.     26  -11    1100   5     28  -10    1150   5
SMITHERS     P.G.      9  -12     500   1     23  -10    1050   3
WELLS GRAY   P.G.     21  -10    1250   5     28   -8    1400   5
FT NLSN      F.N.      9  -26     400   1     11  -20     550   1
FT STJOHN    F.N.      9  -22     700  12      9  -18     700  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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   20   W   39
SMITHERS              VR   5   W   39

TODAY'S VENTING: POOR

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      9    7     100  11     36    8     350  11
FRASER VLY   QUIL      9    6      50  11     19    7     150  11
SRN VRISL    QUIL     15    8     200   3     37    9     450   7
CNTRL VRISL  QUIL     11    6     100   3     13    7     150   3
NRN VRISL    HRDY     15    6     250   3     25    7     400   5
TERRACE      ANT       9   -9     220   4     10   -6     230   6
STEWART      ANT       9   -8      20   4     10   -6      30   6

*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    W   37   W   52   W   56
PORT HARDY   SW  30   W   43   W   50
SANDSPIT     N   26   N   22   NW  20

TODAY'S VENTING: POOR TO FAIR SOUTH. POOR NORTH.

VENTING FOR FRIDAY: POOR

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


END/MWSO