FPCN39 CWLW 301434
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 Friday 30 May 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       9   15     200   2     59   19     900   9
KAMLOOPS     KEL      34   16     800   7    100   21    3350   9
OKANAGAN     KEL      34   16     750   7     81   20    1350  11
CASTLEGAR    SPOK      9   15     500   5     53   20    1300   5
CRANBROOK    SPOK      9   15     950  19    100   20    3950  17
REVELSTOKE   KEL       9    8     450   2     52   16     850   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 FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   S   20   SW  35
CRANBROOK             SW   9   SW  30

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          975 m         18 C
SPOKANE         1160 m         20 C

TODAY'S VENTING: GENERALLY GOOD THIS AFTERNOON.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: GOOD SUNDAY AND TUESDAY.
FAIR MONDAY.


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.    100   15    2550  16    100   23    3950  17
PR. GEORGE   P.G.    100   15    2050  13    100   22    3700  15
SMITHERS     P.G.     28   13     800   7    100   21    2900  14
WELLS GRAY   P.G.     97   12    2050  15    100   23    4000  17
FT NLSN      F.N.     29   16     600   9     97   21    1900  11
FT STJOHN    F.N.     63   17    1350  11    100   24    3700  12


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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  17   SW  26
SMITHERS              VR   5   S   26

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       850 m         14 C
FT. NELSON       800 m         19 C

TODAY'S VENTING: BECOMING GOOD BY LATE MORNING.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY:  GOOD SUNDAY AND TUESDAY.
FAIR MONDAY.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     47   18     550  10     88   20    1200  12
FRASER VLY   QUIL     33   17     350  10     85   20    1100  12
SRN VRISL    QUIL     19   16     250   5     38   18     450   8
CNTRL VRISL  QUIL     15   15     150   5     39   18     450   8
NRN VRISL    HRDY      9   14     250   0     35   17     850   4
TERRACE      ANT      53   16    1700   4     82   21    2650   5
STEWART      ANT      42   16     900   4     72   21    2250   4


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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   28   S   37   SW  46
PORT HARDY   SE  33   SE  44   S   56
SANDSPIT     SE  24   SE  30   SE  37

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       730 m         18 C
PORT HARDY       240 m         13 C
ANNETTE          150 m         13 C

TODAY'S VENTING: FAIR OVER VANCOUVER ISLAND THIS AFTERNOOON. GOOD
ELSEWHERE THIS AFTERNOON.

VENTING FOR SATURDAY: GOOD

VENTING OUTLOOK SUNDAY THROUGH TUESDAY: GENERALLY GOOD.

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

END/PLJ