FPCN39 CWLW 201324
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 20 JULY 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      12   18     500   1     23   25    1600   1
KAMLOOPS     KEL      11   17     550   1     29   27    2500   1
OKANAGAN     KEL      11   16     500   1     27   26    2250   1
CASTLEGAR    SPOK     32   18     850   7     81   27    1550  11
CRANBROOK    SPOK      9   15     950  13     90   25    2250  11
REVELSTOKE   KEL      11   18     650   1     22   23    1750   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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   NW  17   NW  24
CRANBROOK             W   11   W   22

TODAY'S VENTING: POOR

VENTING FOR TUESDAY: POOR

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.     10   12     950  23    100   22    3950  20
PR. GEORGE   P.G.      9   12     700   5    100   20    3700  18
SMITHERS     P.G.      9   12     550   5    100   19    3500  18
WELLS GRAY   P.G.    100   15    4000  20    100   23    4000  20
FT NLSN      F.N.      9   17    1350   0    100   23    3400   7
FT STJOHN    F.N.      9   14    1350   0    100   19    3700   7

*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            W   10   WNW 35
SMITHERS              W   11   NW  30

TODAY'S VENTING: POOR

VENTING FOR TUESDAY: POOR

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     55   19     700   9     72   24    1300   7
FRASER VLY   QUIL     49   18     600   9     76   26    1450   7
SRN VRISL    QUIL      9   17     550   0     64   24    1250   6
CNTRL VRISL  QUIL      9   17     550   0     66   25    1350   6
NRN VRISL    HRDY     22   14     250   6     58   19    1150   6
TERRACE      ANT      72   13     850  15    100   18    1900  11
STEWART      ANT       9   13       0   8     99   18    1450  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 MONDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    NW  19   NW  20   NW  31
PORT HARDY   NW  13   NW  19   NW  26
SANDSPIT     SW  31   SW  37   SW  43

TODAY'S VENTING: GOOD

VENTING FOR TUESDAY: POOR

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


END/MWSO