FPCN39 CWLW 181400
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 WEDNESDAY 18 AUGUST 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       9   21     500   0    100   28    3300  15
KAMLOOPS     KEL      22   23     900   2    100   30    2750   4
OKANAGAN     KEL       9   20     550   0    100   28    2450   3
CASTLEGAR    SPOK     14   20     750   2    100   28    3050   7
CRANBROOK    SPOK      9   18     950  12    100   26    3200  12
REVELSTOKE   KEL       9   17     500   0     80   24    2500   3

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   S   22
CRANBROOK             VR   5   S   22

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: 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.     57   19    1200  08    100   25    3950  17
PR. GEORGE   P.G.     33   15     850  00     86   22    1300  21
SMITHERS     P.G.     39   16     800  12     63   20    1000  15
WELLS GRAY   P.G.      9   16     900   2    100   25    4000  17
FT NLSN      F.N.      9   18     400   2    100   25    3400  10
FT STJOHN    F.N.      9   18     700  13    100   24    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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S  26   SW  37
SMITHERS             VR   5   SW  37

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     31   18     700   4     50   22    1150   5
FRASER VLY   QUIL     34   20     750   4     66   27    1400   6
SRN VRISL    QUIL      9   17     650   0     37   22    1050   3
CNTRL VRISL  QUIL      9   19     700   0     54   26    1350   4
NRN VRISL    HRDY     10   14     100   1     13   17     250   2
TERRACE      ANT      76   16    1200  10    100   18    1550  17
STEWART      ANT      18   14     250   4     73   18    1200   8

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   11   SW  17   SW  35
PORT HARDY   S   33   S   41   S   46
SANDSPIT     S   13   S   22   S   39

TODAY'S VENTING: FAIR EXCEPT GOOD INLAND

VENTING FOR THURSDAY: FAIR

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

END/WJW
$$$$^^