FPCN39 CWLW 111434
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 8:00 AM PDT Wednesday 11 June 1997 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      12   21     500   1     49   25     750   8
KAMLOOPS     KEL      11   19     500   1     44   24     850   8
OKANAGAN     KEL      11   19     500   1     44   24     850   8
CASTLEGAR    SPOK     32   19     800   8     78   25    1950   7
CRANBROOK    SPOK      9   18     950   5    100   23    3950   6
REVELSTOKE   KEL       9   17     500   1     38   23     850   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   W   11
CRANBROOK             E    9   E   20

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          975 m         23 C
SPOKANE          975 m         19 C

TODAY'S VENTING: VENTING WILL BE FAIR FOR MOST AREAS TODAY.
THE WARM AIR IN THE LOW LEVELS AND THE SURFACE INVERSION WILL MEAN
ONLY A SMALL WINDOW -AT MOST- FOR GOOD VENTING THIS AFTERNOON.

VENTING FOR THURSDAY: GOOD.

VENTING OUTLOOK FRIDAY THRU SUNDAY: FAIR TO 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.      9   17     950   8     61   23    1750   9
PR. GEORGE   P.G.     24   17     850   9     44   23    1100  10
SMITHERS     P.G.     15   15     650   4     31   19     900   7
WELLS GRAY   P.G.      9   16    1000   8    100   24    4000  12
FT NLSN      F.N.     18   16     500   8    100   24    3400   6
FT STJOHN    F.N.      9   14     700   8    100   22    3700   6

*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            E   17   E   28
SMITHERS              VR   5   SE  28

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1180 m         26 C
FT. NELSON       670 m         21 C

TODAY'S VENTING: SHARP INVERSION PRESENT OVER REGIONS. THE LOWER
LYING AREAS WILL SEE THE LEAST FAVOURABLE CONDITIONS BECAUSE OF THE
HIGH BREAKTHROUGH TEMPERATURE NECESSARY.

VENTING FOR THURSDAY: GOOD.

VENTING OUTLOOK FRIDAY THRU SUNDAY: FAIR TO GOOD.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     75   17     750  15    100   21    1250  16
FRASER VLY   QUIL     70   16     650  15    100   22    1400  16
SRN VRISL    QUIL     67   17     700  12     94   21    1100  14
CNTRL VRISL  QUIL     76   18     800  13     95   21    1150  14
NRN VRISL    HRDY      9   13       0   2     28   15     600   4
TERRACE      ANT      80   16    1000  15    100   22    3200  19
STEWART      ANT      53   17     700   8    100   22    3000  17

*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    VR   5   SW   9   S   13
PORT HARDY   VR   5   S   11   SE  26
SANDSPIT     S   11   SE  11   SE  22

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      nil  m         ## C
PORT HARDY      nil  m         ## C
ANNETTE         nil  m         ## C

TODAY'S VENTING:
WEAK OR NO INVERSION EVIDENT THIS MORNING. LOW LEVEL WINDS WILL
FAVOUR GOOD VENTING OVER MOST AREAS ALTHOUGH THE MIXING HEIGHTS WILL
NOT BE HIGH.

VENTING FOR THURSDAY: GOOD.

VENTING OUTLOOK FRIDAY THRU SUNDAY: FAIR.

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

END/BJS