FPCN39 CWLW 131346
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 WEDNESDAY 13 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   18     550   1    100   21    1000  20

KAMLOOPS     KEL      12   18     600   1    100   25    2500   9

OKANAGAN     KEL      11   16     550   1     88   24    2100   8

CASTLEGAR    SPOK     32   15     900   6    100   22    2750  10

CRANBROOK    SPOK     68   16    2050   8    100   23    3950  10

REVELSTOKE   KEL      11   17     600   1    100   24    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         1550 m         21 C
SPOKANE         1050 m         16 C

TODAY'S VENTING: GOOD
VENTING FOR THURSDAY: GOOD
VENTING OUTLOOK FRIDAY THRU SUNDAY: GENERALLY GOOD FRIDAY AND
SATURDAY.

 FAIR ON SUNDAY.


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   13    1050   8    100   20    3950  13

PR. GEORGE   P.G.     22   13     850   9     93   21    2250  10

SMITHERS     P.G.     12   12     700   2     75   17    2050  12

WELLS GRAY   P.G.     23   14    1200   8    100   21    4000  13

FT NLSN      F.N.     15   15     750   5     75   18     850  21

FT STJOHN    F.N.     13    8     750   0    100   19    1600  25


*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      1150 m         19 C
FT. NELSON       900 m         22 C

TODAY'S VENTING: GOOD
VENTING FOR THURSDAY: GOOD

VENTING OUTLOOK FRIDAY THRU SUNDAY: GENERALLY GOOD FRIDAY AND
SATURDAY.

 FAIR ON SUNDAY.


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      1150 m         20 C
PORT HARDY       850 m         23 C
ANNETTE         2000 m          8 C

TODAY'S VENTING: GOOD
VENTING FOR THURSDAY: GOOD
VENTING OUTLOOK FRIDAY THRU SUNDAY: GENERALLY GOOD FRIDAY AND
SATURDAY.

 FAIR ON SUNDAY.


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


END/MWSO