FPCN39 CWLW 141345
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 PDT THURSDAY 14 MAY 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      13   12     550   1     54   16    1000   7
KAMLOOPS     KEL      12   12     600   1    100   18    2500   9
OKANAGAN     KEL      11   11     550   1     88   18    2100   8
CASTLEGAR    SPOK     32   14     900   6    100   16    2750  15
CRANBROOK    SPOK     68   15    2050   8    100   18    3950  16
REVELSTOKE   KEL      11   15     600   1    100   18    2450   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
PENTICTON    VR   5   SW   9   SW  15
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          900 m         13 C
SPOKANE         1300 m         14 C

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD

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.     19   10    1050   8    100   15    3950   13
PR. GEORGE   P.G.     22   10     850   9     93   16    2250   10
SMITHERS     P.G.     12    9     700   2     40   15    1050   10
WELLS GRAY   P.G.     23   11    1200   8    100   14    4000   13
FT NLSN      F.N.     13   12     750   8     43   18      50   15
FT STJOHN    F.N.     20   11    1300   8     55   19    1600   15

*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            S   30   S   37
SMITHERS              S   28   S   37

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       100 m          8 C
FT. NELSON      1500 m         18 C

TODAY'S VENTING: FAIR

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     66   14    1200   7     73   17    1350   7
FRASER VLY   QUIL     70   15    1250   7     76   18    1450   7
SRN VRISL    QUIL     63   15    1200   6     70   18    1400   6
CNTRL VRISL  QUIL     50   13     900   6     65   16    1300   6
NRN VRISL    HRDY     71   11    1000   9     75   13    1300   8
TERRACE      ANT      88    9    1550  10    100   12    2150  10
STEWART      ANT      60   10     850   8    100   12    1900  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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  24   SW  30   SW  43
PORT HARDY   S   37   SW  50   SW  59
SANDSPIT     S   31   S   35   S   43

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       640 m         10 C
PORT HARDY       150 m          8 C
ANNETTE          150 m          8 C

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD SATURDAY. FAIR SUNDAY
AND MONDAY.

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


END/MWSO