FPCN39 CWLW 041318
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 SUNDAY 4 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      19    5    1500   1     38   12    2850   1
KAMLOOPS     KEL      27    8    2300   1     43   12    2900   1
OKANAGAN     KEL      24    7    1850   1     42   11    2850   1
CASTLEGAR    SPOK     44    7    1850   3     86   11    3500   4
CRANBROOK    SPOK     64    5    2700   4     91   10    3950   5
REVELSTOKE   KEL      26    7    2250   1     41   10    2850   1

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  13   SW  26
CRANBROOK             W   11   W   26

TODAY'S VENTING: FAIR

VENTING FOR MONDAY: FAIR

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.     68    2    2150   7    100    6    3950   8
PR. GEORGE   P.G.     25    1     950   7     98    6    2800   8
SMITHERS     P.G.     11   -1     650   2     48    4    1300   4
WELLS GRAY   P.G.     15   -2     800   8    100    7    4000   8
FT NLSN      F.N.     45    1     800  11    100    5    2050  13
FT STJOHN    F.N.     86    1    1600  14    100    4    2950  14

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            E    9   SE  22
SMITHERS              E   28   E   22

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: FAIR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     18    5     250   6     91    9    1750   8
FRASER VLY   QUIL     21    6     250   6     93   10    1800   8
SRN VRISL    QUIL     47    7     650   7     91   10    1800   8
CNTRL VRISL  QUIL     17    4     200   6     91   10    1800   8
NRN VRISL    HRDY     36    5     350   9     84    8    1650   7
TERRACE      ANT      78    2     750  19    100    8    2700  18
STEWART      ANT      19    3     600   7    100    8    2100  16

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   24   SW  31   SW  37
PORT HARDY   S   41   S   46   S   43
SANDSPIT     E   52   E   39   NE  46

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: GOOD

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

END/MWSO