FPCN39 CWLW 291400
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 29 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      17   24     600   2     78   27    1150  13
KAMLOOPS     KEL      14   23     600   2     82   28    2250   9
OKANAGAN     KEL      13   20     550   2     85   30    2450   8
CASTLEGAR    SPOK     37   22     750  12     95   32    1650  13
CRANBROOK    SPOK     10   22     950  13    100   30    2500  22
REVELSTOKE   KEL      12   21     550   2     43   23     600   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    W   13   W   30   W   41
CRANBROOK             W   19   W   44

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: FAIR


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    3950  31    100   20    3950  31
PR. GEORGE   P.G.    100   13    1450  31    100   19    3700  30
SMITHERS     P.G.      9   11     500   4    100   19    3500  25
WELLS GRAY   P.G.      8   13     450   6    100   20    4000  31
FT NLSN      F.N.      9   12     400  11    100   14    1100  27
FT STJOHN    F.N.    100   13    1550  28    100   17    2450  28

*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            W   30   W   37
SMITHERS              W   24   NW  37

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: FAIR


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     51   17     900   7     69   21    1150   8
FRASER VLY   QUIL     60   18     950   8     81   23    1300   9
SRN VRISL    QUIL     49   17     850   6     68   22    1200   7
CNTRL VRISL  QUIL     51   18     900   6     68   22    1200   7
NRN VRISL    HRDY     31   14     500   5     42   16     900   4
TERRACE      ANT      43   14    1500   3     66   18    2050   4
STEWART      ANT      26   14     700   3     55   18    1800   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   11   W   20   W   30
PORT HARDY   NW  15   N   11   NW  19
SANDSPIT     NW  17   NW  26   NW  30

TODAY'S VENTING: GOOD EXCEPT FAIR NROTH END VANCOUVER ISLAND.

VENTING FOR FRIDAY: FAIR


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

END/JEM
$$$$^^