FPCN39 CWLW 041431
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 FRIDAY 4 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    1     500   0     40    5    1200   3
KAMLOOPS     KEL       9    0     550   0     40    5    1600   3
OKANAGAN     KEL       9    0     550   0     40    5    1600   3
CASTLEGAR    SPOK     22    1     850   4     50    4    1800   4
CRANBROOK    SPOK      9   -3     950   4     67    1    2350   6
REVELSTOKE   KEL      11    0     650   1     40    3    1350   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   13   NW  22
CRANBROOK             NW   9   NW  19

TODAY'S VENTING: FAIR THIS AFTERNOON EXCEPT GOOD ABOVE 900 METRES.

VENTING FOR SATURDAY: 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.     10   -4     950   7     10   -2     950   7
PR. GEORGE   P.G.      9   -4     850   0     19   -3     950   4
SMITHERS     P.G.      9   -5     550   0      9   -3     800   0
WELLS GRAY   P.G.      9  -10    1000   2     10   -2    1000   7
FT NLSN      F.N.      9  -15     400   3      9  -13     400   3
FT STJOHN    F.N.      9  -13     700   5     15  -10     800   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
PR. GEORGE            W   28   W   30
SMITHERS              SW  26   SW  30

TODAY'S VENTING: POOR EXCEPT GOOD ABOVE 1200 METRES THIS AFTERNOON
OVER EASTERN SECTIONS OF THE CENTRAL INTERIOR.

VENTING FOR SATURDAY: POOR TO FAIR.




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     26    5     300   8     77    7     850  13
FRASER VLY   QUIL     23    4     250   8     69    7     750  12
SRN VRISL    QUIL     23    5     250   6     48    7     550   9
CNTRL VRISL  QUIL     21    4     250   6     32    6     300   9
NRN VRISL    HRDY     26    5     450   4     57    7     850   7
TERRACE      ANT       9    0     250   5      9    1     250   5
STEWART      ANT       9    0     250   5     10    1      50   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  24   W   28   W   33
PORT HARDY   S   22   SW  24   W   30
SANDSPIT     S   67   SW  61   SW  52

TODAY'S VENTING: FAIR TO GOOD THIS AFTERNOON EXCEPT POOR ON THE NORTH
COAST.

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