FPCN39 CWLW 311400
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 SATURDAY 31 JULY 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      22   21     850   2    100   29    3200   7
KAMLOOPS     KEL      28   20    1100   3    100   29    3350   7
OKANAGAN     KEL      13   19     700   1    100   29    3350   7
CASTLEGAR    SPOK     28   21     850   6     90   29    3500   5
CRANBROOK    SPOK      9   19     950   1     88   27    3950   4
REVELSTOKE   KEL      26   19    1050   3    100   25    3450   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   SE  15

TODAY'S VENTING: GOOD.

VENTING FOR SUNDAY: 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   14    2050  18    100   22    3950  12
PR. GEORGE   P.G.     41   13     950  14    100   21    3700  12
SMITHERS     P.G.     37   14     950   8    100   22    3500   8
WELLS GRAY   P.G.     39   10    1200  10    100   22    4000  12
FT NLSN      F.N.     11   14     600   1    100   21    2450   9
FT STJOHN    F.N.     43   13    1150   9    100   20    3700  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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            NE  22   E   22
SMITHERS              E   20   E   22

TODAY'S VENTING: GOOD.

VENTING FOR SUNDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     28   12     700   7     60   25    2000   8
FRASER VLY   QUIL     26   12     700   6     69   27    2000   6
SRN VRISL    QUIL      9   17     550   0     46   23    1350   0
CNTRL VRISL  QUIL      9   20     750   0     48   26    3050   0
NRN VRISL    HRDY     23   14     350   4     26   17     450   4
TERRACE      ANT      10   17     250   9    100   24    3200   6
STEWART      ANT      19   17     150   7     78   24    1200   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 SATURDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   VR   5   VR   5
PORT HARDY   VR   5   SE  11   E    9
SANDSPIT     N   19   NE  24   N   31

TODAY'S VENTING: FAIR TO GOOD.

VENTING FOR SUNDAY: GOOD

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


END/MWSO
$$$$^^