FPCN39 CWLW 021340
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 PST THURSDAY 2 APRIL 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    8     550   1     81   15    2400   5
KAMLOOPS     KEL      22   10    1100   2     86   15    2450   6
OKANAGAN     KEL      12    7     600   1     86   15    2450   6
CASTLEGAR    SPOK     24    7     800   5     71   14    2250   5
CRANBROOK    SPOK      9    6     950   3     88   13    2850   8
REVELSTOKE   KEL      10    5     550   1     64   12    1900   5

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   S   15   S   30
CRANBROOK             VR   5   S   20

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          800 m          8 C
SPOKANE          900 m          7 C

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: GENERALLY 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    4     950   2     99   10    3050   8
PR. GEORGE   P.G.     14    3     800   4     79    8    2150   7
SMITHERS     P.G.     17    1     650   4     49    6    1200   7
WELLS GRAY   P.G.     23    4    1300   5     78    6    2300   8
FT NLSN      F.N.     15    2     450  11     33    7     600  11
FT STJOHN    F.N.      9    3     700  12     83    8    2000   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            VR   5   S   22
SMITHERS              VR   5   SW  22

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       900 m          6 C
FT. NELSON       700 m          8 C

TODAY'S VENTING: GOOD TO FAIR

VENTING FOR FRIDAY: GOOD TO FAIR

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD TO FAIR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     20    8     650   2     55   11    1650   4
FRASER VLY   QUIL     13    7     250   2     67   13    2050   4
SRN VRISL    QUIL     15    8     250   3     57   12    1750   4
CNTRL VRISL  QUIL     44   10    1250   3     65   13    2000   4
NRN VRISL    HRDY      9    6       0   3     53    9    1200   5
TERRACE      ANT      36    5     800   5     62    8    1200   7
STEWART      ANT      24    5     300   5     54    8    1050   5

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   S    9   S   24
PORT HARDY   VR   5   VR   5   VR   5
SANDSPIT     NW  24   NW  19   W   17

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       250 m          8 C
PORT HARDY       120 m          7 C
ANNETTE          800 m          6 C

TODAY'S VENTING: GOOD LOCALLY FAIR

VENTING FOR FRIDAY: GOOD TO FAIR

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD TO FAIR

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


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