FPCN39 CWLW 291433
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 TUESDAY 29 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     200   8     50    5     550  15
KAMLOOPS     KEL      20    1     500   8     45    4     550  12
OKANAGAN     KEL      20    1     500   8     40    4     550  12
CASTLEGAR    SPOK      9    3     500   5      9    4     500  15
CRANBROOK    SPOK      9   -2     950   5      9    2     950  10
REVELSTOKE   KEL      12    0     500   8     17    2     550   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W   17   W   44   W   98
CRANBROOK             W   33   W  100

TODAY'S VENTING: POOR THIS MORNING RISING TO FAIR THIS AFTERNOON IN
THE SOUTHWEST.

VENTING FOR WEDNESDAY: 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   -4     800   8     56   -2    1200  15
PR. GEORGE   P.G.     20  -10    1000   5     39   -8    1050  10
SMITHERS     P.G.     18   -9     950   5     30   -6    1000   8
WELLS GRAY   P.G.     20  -12     950   5     35   -3    1000  15
FT NLSN      F.N.     20  -24     850   3     21  -23     900   3
FT STJOHN    F.N.     23  -23    1000   5     25  -22    1050   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   35   W   39
SMITHERS              W   43   W   39

TODAY'S VENTING: POOR THIS MORNING RISING TO FAIR OVER WELLS GRAY
AND PRINCE GEORGE THIS AFTERNOON AND GOOD AT WILLIAMS LAKE.

VENTING FOR WEDNESDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     28    9     300  12     78   10     400  22
FRASER VLY   QUIL      9    8      50   7     62   11     550  15
SRN VRISL    QUIL     25   10     300  12     59   11     450  18
CNTRL VRISL  QUIL     13    9     150   4     60   11     500  14
NRN VRISL    HRDY      9    7       0  10     35    8     300  10
TERRACE      ANT       9   -6     200  15      9   -4     200   8
STEWART      ANT       9   -8     200   8     25   -4     200  13


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

FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   56   W   76   W   83
PORT HARDY   W   39   W   56   W   69
SANDSPIT     W   43   W   44   W   46

TODAY'S VENTING: POOR THIS MORNING RISING TO FAIR TO GOOD OVER THE
SOUTHWEST. REMAINING POOR ELSEWHERE.




VENTING FOR WEDNESDAY: POOR




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


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