FPCN39 CWLW 181323
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 MONDAY 18 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      33   15     600   6    100   20    2350   8

KAMLOOPS     KEL      93   17    2150   8    100   21    3350   9

OKANAGAN     KEL      85   16    1950   8    100   21    3350   9

CASTLEGAR    SPOK      9   12     500  17    100   16    3500  21

CRANBROOK    SPOK    100   10    3950  21    100   16    3950  21

REVELSTOKE   KEL      82   15    1950   8    100   21    3450   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  11   S   13
CRANBROOK             VR   5   NW  13

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         NONE
SPOKANE         NONE

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: GOOD.

VENTING OUTLOOK WEDNESDAY THRU FRIDAY: 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.     79   14    2050  10    100   19    3950   8

PR. GEORGE   P.G.     70   14    1400  12    100   20    3700   9

SMITHERS     P.G.     54   13    1200   8     88   18    2050   9

WELLS GRAY   P.G.     81   14    2300   9    100   19    4000   8

FT NLSN      F.N.      9   17     400  13    100   24    3400   8

FT STJOHN    F.N.      9   15     700   7    100   21    3700   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            NW  17   NW  20
SMITHERS              W   11   SW  20

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1500 m         15 C
FT. NELSON       720 m         18 C

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: GOOD

VENTING OUTLOOK WEDNESDAY THRU FRIDAY: GOOD.


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     60   13    1200   6     93   16    2050   8

FRASER VLY   QUIL     60   13    1150   6     92   16    1950   8

SRN VRISL    QUIL     17   12     800   1     92   17    2150   7

CNTRL VRISL  QUIL     19   13    1050   1     92   17    2200   7

NRN VRISL    HRDY     62   11     950   8     75   14    1400   7

TERRACE      ANT      27   11    1050   2     57   15    1900   4

STEWART      ANT      22   12     800   2     41   15    1500   2


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

FORECAST UPPER WINDS FOR MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW   9   W   11   VR   5
PORT HARDY   NW  15   VR   5   VR   5
SANDSPIT     SW  13   S   24   S   31

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      NONE
PORT HARDY      NONE
ANNETTE         NONE

TODAY'S VENTING: GOOD.

VENTING FOR TUESDAY: GOOD

VENTING OUTLOOK WEDNESDAY THRU FRIDAY: GOOD.

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

END/JEM