FPCN39 CWLW 101330
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 10 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      12   21     500   1     19   29    1150   1
KAMLOOPS     KEL      11   21     500   1     24   31    1950   1
OKANAGAN     KEL      11   21     500   1     21   30    1500   1
CASTLEGAR    SPOK     19   22     750   4     32   29    1100   4
CRANBROOK    SPOK     15   21    1000   8    100   29    3950   9
REVELSTOKE   KEL       9   19     500   1     16   26    1100   1

*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   VR   5   SW  13
CRANBROOK             VR   5   SW  11

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.     90   18    3900    8   100   25    3900   8
PR. GEORGE   P.G.     70   19    3400    8   100   24    3400   8
SMITHERS     P.G.     70   19    3400    8   100   22    3400   8
WELLS GRAY   P.G.     90   19    4000    6   100   22    4000   6
FT NLSN      F.N.     27   19     750    5    78   27    3400   4
FT STJOHN    F.N.     78   17    3700    4    78   25    3700   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
PR. GEORGE
SMITHERS              SW  22   SW

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     30   17     500   5     66   23    1850   6
FRASER VLY   QUIL     31   18     550   5     68   25    2000   6
SRN VRISL    QUIL      9   15     450   0     60   22    1750   3
CNTRL VRISL  QUIL      9   19     550   0     74   27    1400   5
NRN VRISL    HRDY     11   13     100   2     73   17    1500   3
TERRACE      ANT      93   16    1150  16    100   22    3200  17
STEWART      ANT      78   16     800  13    100   22    1700  14

*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    W   13   W   11   SW  20
PORT HARDY   SW  13   S   26   SW  31
SANDSPIT     SW  26   SW  26   SW  31

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/GF