FPCN39 CWLW 201400
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 THURSDAY 20 MAY 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     100   14    5600  25    100   18    7400  25
KAMLOOPS     KEL      24   15    1100   2    100   19    3350   8
OKANAGAN     KEL      13   12     550   2    100   18    3350   8
CASTLEGAR    SPOK     19   12     850   3    100   18    2050   8
CRANBROOK    SPOK      9   10     950   3    100   16    2550   8
REVELSTOKE   KEL      11   11     550   2    100   16    3450   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   11   W   17
CRANBROOK             VR   5   SE  22

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: 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   10    3950  12    100   14    3950  12
PR. GEORGE   P.G.     18    9     850   6    100   14    3700  10
SMITHERS     P.G.      9    7     500   2    100   13    3450   7
WELLS GRAY   P.G.    100   10    3950  12    100   14    4000  12
FT NLSN      F.N.     11   10     750   1    100   16    2300   3
FT STJOHN    F.N.     15    9    1000   2    100   15    3700   6

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

FORECAST UPPER WINDS FOR THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            VR   5   SW  13
SMITHERS              S   22   S   13

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD




COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     15   12    1100   3     70   15    1450  11
FRASER VLY   QUIL     25   10     200   4     90   15    1900  11
SRN VRISL    QUIL     21   10     550   2     86   14    1300  11
CNTRL VRISL  QUIL     34   12    1000   3     89   15    1400  11
NRN VRISL    HRDY     22    9     300   5     81   12    1150  11
TERRACE      ANT     100    9    1050  34    100   12    1850  10
STEWART      ANT      91    9     500  28    100   12    1200  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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   13   W   15   W   15
PORT HARDY   S   20   S   30   S   26
SANDSPIT     S   44   S   48   S   46

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD




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


END/
$$$$^^