FPCN39 CWLW 231417
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 WEDNESDAY 23 DECEMBER 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       9   -9     200   7      9   -8     200   7
KAMLOOPS     KEL      20   -8     500   7     34   -7    1000   4
OKANAGAN     KEL      34   -7    1000   4     46   -6    1500   4
CASTLEGAR    SPOK     14  -11     750   2     24   -8    1250   2
CRANBROOK    SPOK      9  -19     950  14      9  -15     950  14
REVELSTOKE   KEL       9  -11     450   7      9  -10     450   7

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   NW  28
CRANBROOK             VR   5   W   30

TODAY'S VENTING: POOR LOCALLY FAIR

VENTING FOR THURSDAY: 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.     30  -12    1300   6     32  -11    1350   6
PR. GEORGE   P.G.     15  -13     950   3     21  -11    1200   3
SMITHERS     P.G.     23  -11     950   4     26  -10    1050   4
WELLS GRAY   P.G.     30  -12    1300   6     32  -11    1400   6
FT NLSN      F.N.      9  -25     400   0      9  -19     550   0
FT STJOHN    F.N.      9  -17     700   9      9  -13     700   9

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  24   W   26
SMITHERS              S   24   S   26

TODAY'S VENTING: POOR

VENTING FOR THURSDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9   -4     100   3      9   -1     100   3
FRASER VLY   QUIL      9   -6      50   3      9   -3      50   3
SRN VRISL    QUIL     21    0     200   6     21    1     350   4
CNTRL VRISL  QUIL     17   -1     150   6     17   -1     150   6
NRN VRISL    HRDY      9    1       0   9      9    1       0   9
TERRACE      ANT       9   -9     200  11      9   -8     200  11
STEWART      ANT       9   -9      20   6      9   -8       0   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SE  22   SW  22   W   26
PORT HARDY   S   54   S   57   SW  44
SANDSPIT     SE  41   S   30   SW  24

TODAY'S VENTING: POOR

VENTING FOR THURSDAY: POOR

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


END/MWSO