FPCN39 CWLW 271400
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 TUESDAY 27 APRIL 1999 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      32    9    1400   2     97   14    3200  12
KAMLOOPS     KEL      43    9    2350   2     97   13    3350  12
OKANAGAN     KEL      14    6     600   2     97   14    3350  12
CASTLEGAR    SPOK     55    7    1100  10    100   13    3500  11
CRANBROOK    SPOK    100    6    2900  17    100   12    3950  11
REVELSTOKE   KEL      35    7    1850   2     97   11    3450  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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   13   W   15
CRANBROOK             VR   5   SW  11

TODAY'S VENTING: GOOD

VENTING FOR WEDNESDAY: 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.    100    5    2850  12    100   10    3950  11
PR. GEORGE   P.G.     33    3     950  11    100   10    3700  11
SMITHERS     P.G.     17    3     850   3    100   10    3500   9
WELLS GRAY   P.G.    100    5    2850  12    100   10    4000  11
FT NLSN      F.N.     29    2     900   4     77    6    2050   5
FT STJOHN    F.N.     55    1    1700   6     75    5    2300   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            N   24   NE  26
SMITHERS              NW   9   VR  26

TODAY'S VENTING: GOOD

VENTING FOR WEDNESDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     72    9    1450   6     93   12    2500   6
FRASER VLY   QUIL     56    7     800   8     92   12    2450   6
SRN VRISL    QUIL     50    7     650   8     89   12    2300   6
CNTRL VRISL  QUIL     51    7     700   8     89   12    2350   6
NRN VRISL    HRDY     33    6     550   5     99   10    1650   5
TERRACE      ANT       9    5     250   7     92   11    3200   5
STEWART      ANT      13    5     200   3     81   11    2400   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   19   NW  20   N   20
PORT HARDY   NW  26   N   17   VR   5
SANDSPIT     NW   9   VR   5   VR   5

TODAY'S VENTING:  GOOD


VENTING FOR WEDNESDAY: GOOD




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


END/
$$$$^^