FPCN39 CWLW 121400
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 WEDNESDAY 12 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      52   11     500  12     92   15    1850  18
KAMLOOPS     KEL      36   11     500   4    100   15    2350  10
OKANAGAN     KEL      46   11     500   8    100   15    2350   9
CASTLEGAR    SPOK     33   11    1050   5    100   14    1800  14
CRANBROOK    SPOK     30    6    1900   5    100   13    3950  17
REVELSTOKE   KEL      12   10     500   4     89   13    2050   9

*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    W   13   W   22   W   26
CRANBROOK             W   13   W   35

TODAY'S VENTING: POOR TO FAIR THIS MORNING RISING TO GOOD THIS
AFTERNOON.

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.     52    7    2050  10     88   11    2850   7
PR. GEORGE   P.G.     50    8    1350   8     92   11    2350   9
SMITHERS     P.G.     29    7     750   9     88   11    2000   9
WELLS GRAY   P.G.     30    3    1300  12    100   11    4000  15
FT NLSN      F.N.     18    8     650   4     49   14     800   8
FT STJOHN    F.N.      9    9     700   8     24   11     800  12

*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            W   19   W   17
SMITHERS              W    9   VR  17

TODAY'S VENTING: FAIR TO POOR THIS MORNING INCREASING TO FAIR TO GOOD
THIS AFTERNOON. EXCEPT REMAINING POOR OVER NORTHEAST BC.

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     80   11    1100  12    100   14    2800  16
FRASER VLY   QUIL     80   10    1200  10    100   13    2700  14
SRN VRISL    QUIL    100   10    1500  12    100   14    2250  12
CNTRL VRISL  QUIL    100   10    1550  12    100   13    2150  12
NRN VRISL    HRDY     10    6     100   2     79   10    1550   7
TERRACE      ANT      70    6    1350  10    100   10    2200  16
STEWART      ANT      87    8     950  14    100   10    1600  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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   26   W   26   W   26
PORT HARDY   SW  15   SW  22   SW  22
SANDSPIT     S   22   S   17   VR   5

TODAY'S VENTING: GOOD EXCEPT POOR THIS MORNING OVER NORTHERN
VANCOUVER ISLAND.

VENTING FOR THURSDAY: GOOD


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


END/
$$$$^^