FPCN39 CWLW 261400
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 26 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      23   11     900   2    100   16    3200  12
KAMLOOPS     KEL      30   10    1450   2    100   16    3350  10
OKANAGAN     KEL      12    7     500   2    100   16    3350  10
CASTLEGAR    SPOK     20   10    1350   5    100   15    2350  10
CRANBROOK    SPOK     20   11    2450   6    100   16    3950  12
REVELSTOKE   KEL      27    9    1400   2     85   14    3450  10

*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   W   13   SW  19
CRANBROOK             SW  11   SW  24

TODAY'S VENTING: GOOD IN THE AFTERNOON.

VENTING FOR TUESDAY: 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.     40    4    1250   8    100   11    3950   8
PR. GEORGE   P.G.     54    4    1300   9    100   10    3700   8
SMITHERS     P.G.     28    4    1000   4    100   10    3500   7
WELLS GRAY   P.G.     20    3    1150   6    100   11    4000   8
FT NLSN      F.N.     25    2    1100   9     84    7    1650  10
FT STJOHN    F.N.     28    3    2200   8    100   10    3700  11

*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  13   NW   9
SMITHERS              VR   5   VR   9

TODAY'S VENTING: GOOD IN THE AFTERNOON.

VENTING FOR TUESDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     61    8    1450   5     79   10    2150   5
FRASER VLY   QUIL     58    8    1400   5     78   10    2100   5
SRN VRISL    QUIL     29    7     800   3     78   11    2250   5
CNTRL VRISL  QUIL     30    7     850   3     79   11    2300   5
NRN VRISL    HRDY     10    5     150   1     20    9     550   2
TERRACE      ANT      83    5    1500   9    100    9    2850  10
STEWART      ANT      58    6     900   7    100    9    2150   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
VANCOUVER    VR   5   SW  11   SW  15
PORT HARDY   W   17   W   13   S   19
SANDSPIT     S   15   S    9   VR   5

TODAY'S VENTING: GOOD IN THE AFTERNOON.

VENTING FOR TUESDAY: GOOD

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


END/MWSO
$$$$^^