FPCN39 CWLW 171400
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 FRIDAY 17 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       9   16     600   0     78   27    2200   5
KAMLOOPS     KEL      24   16     700   4     72   26    2450   5
OKANAGAN     KEL       9   16     550   0     68   26    2400   5
CASTLEGAR    SPOK     26   16     800   4     65   25    1450   8
CRANBROOK    SPOK     23   15    1200   4     62   23    2300   6
REVELSTOKE   KEL       9   14     500   0     41   21    1150   4

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   N   17   N   24
CRANBROOK             W   11   NW  19

TODAY'S VENTING: GOOD.


VENTING FOR SATURDAY: 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   12     950   6    100   21    3950   8
PR. GEORGE   P.G.     16   10     850   5    100   20    2600   8
SMITHERS     P.G.     15   10     800   2     65   17    1850   6
WELLS GRAY   P.G.     ##   ##     ###  ##    100   22    4000  15
FT NLSN      F.N.      9    9     400   5    100   17    3400  25
FT STJOHN    F.N.      9   10     700  26    100   17    3700  29

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            W   19   NW  43
SMITHERS              W   13   W   43

TODAY'S VENTING: GOOD.


VENTING FOR SATURDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     23   16     400   5     56   21    1600   7
FRASER VLY   QUIL     17   15     200   3     60   23    1700   6
SRN VRISL    QUIL     21   15     300   4     60   21    1600   8
CNTRL VRISL  QUIL     16   15     200   3     62   22    1500   7
NRN VRISL    HRDY     27   14     450   4     52   17     950   6
TERRACE      ANT      43   13    1100   5     72   18    1800   6
STEWART      ANT      23   13     400   4     56   18    1300   5

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

FORECAST UPPER WINDS FOR FRIDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    NW  13   N   15   N   19
PORT HARDY   N   19   NW  15   NW  26
SANDSPIT     SW  39   SW  31   SW  35

TODAY'S VENTING: GOOD.


VENTING FOR SATURDAY: GOOD




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


END/MWSO
$$$$^^