FPCN39 CWLW 121400
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 12 SEPTEMBER 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      39   16     850   5    100   26    2550   8
KAMLOOPS     KEL      30   14     800   5     87   23    2250   7
OKANAGAN     KEL      15   12     550   3     79   22    2050   6
CASTLEGAR    SPOK     28   14     850   6     86   23    2400   7
CRANBROOK    SPOK      9   11     950   6    100   21    3950   7
REVELSTOKE   KEL      26   13     800   5     85   22    2250   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   N   11   NE  24
CRANBROOK             VR   5   VR   5

TODAY'S VENTING: GOOD

VENTING FOR MONDAY: 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.      9    9     950   9     97   19    2500  11
PR. GEORGE   P.G.     18    9     850   6     90   18    2150   9
SMITHERS     P.G.      9   10     850   0     53   18    1550   5
WELLS GRAY   P.G.      9    5     800   3     96   19    2550  11
FT NLSN      F.N.      9   11     400   3    100   18    2100  13
FT STJOHN    F.N.      9   12     700   9    100   19    3700  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
PR. GEORGE            W   11   NW  22
SMITHERS              SW  11   W   22

TODAY'S VENTING: GOOD EXCEPT FAIR VICINITY SMITHERS

VENTING FOR MONDAY: GOOD


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    HRDY     15   15     450   8     53   21     700   9
FRASER VLY   HRDY     15   20     700   9     83   29    1300   9
SRN VRISL    HRDY     15   14     300   8     90   22     750   9
CNTRL VRISL  HRDY     15   17     500   8     63   24     850   9
NRN VRISL    HRDY     29   13     350   6     35   17     500   6
TERRACE      ANT      13   13     600   1     74   20    1450   8
STEWART      ANT      13   13     250   2     70   20    1200   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    E   26   E   35   NE  26
PORT HARDY   VR   5   SE  17   SE  11
SANDSPIT     S   20   S   30   S   39

TODAY'S VENTING: GOOD EXCEPT FAIR VANCOUVER AND NORTHERN VANCOUVER
 ISLAND.

VENTING FOR MONDAY: GOOD


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


END/RNR/JM
$$$$^^