FPCN39 CWLW 151455 AMD
REVISED SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR
INCLUDING THE NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE
OF ENVIRONMENT CANADA AT 7.39 AM PDT WEDNESDAY 15 JULY 1998 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      24   21     550   4     70   28    1850   5
KAMLOOPS     KEL      15   18     500   4     79   27    2150   6
OKANAGAN     KEL      17   19     550   4     95   28    2550   7
CASTLEGAR    SPOK     23   19     750   6     61   26    1350   8
CRANBROOK    SPOK     10   17     950  10    100   25    3950  16
REVELSTOKE   KEL      11   17     500   4     25   22    1000   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   SW  17   SW  33
CRANBROOK             SW  13   SW  37

VENTING FOR THURSDAY: 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.     10   16     950  21    100   23    3950  24
PR. GEORGE   P.G.     16   14     850   5    100   21    2350  18
SMITHERS     P.G.     23   15     800   5    100   21    1950  17
WELLS GRAY   P.G.    100   16    1700  25    100   23    4000  24
FT NLSN      F.N.     25   12     550  10    100   20    2100  21
FT STJOHN    F.N.    100   13    1850  23    100   20    3700  23

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE
SMITHERS              S   26   S

VENTING FOR THURSDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     64   17     700  12     80   19    1000  12
FRASER VLY   QUIL     64   17     650  12     90   20    1200  12
SRN VRISL    QUIL      9   16     500   0     54   19     900   7
CNTRL VRISL  QUIL      9   16     500   0     64   20    1150   7
NRN VRISL    HRDY      9   13       0  19     70   17     450  20
TERRACE      ANT      92   14     750  27    100   20    2250  34
STEWART      ANT      60   15     500  14    100   20    1700  26

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

FORECAST UPPER WINDS FOR WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    S   15   S   30   S   43
PORT HARDY   SE  22   S   37   S   37
SANDSPIT     S   35   S   41   S   44

VENTING FOR THURSDAY: GOOD

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

END/mwso