FPCN39 CWLW 291434
SMOKE CONTROL FORECAST FOR COASTAL BC AND THE INTERIOR INCLUDING THE
NORTHEAST ISSUED BY THE MOUNTAIN WEATHER SERVICE OFFICE OF
ENVIRONMENT CANADA AT 8:00 AM PDT Tuesday 29 July 1997 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      67   27    1000  15    100   33    2550  15
KAMLOOPS     KEL      11   24     750   3     82   33    2200   6
OKANAGAN     KEL      11   23     700   1    100   34    3350   7
CASTLEGAR    SPOK     31   24     900   6    100   34    3500   6
CRANBROOK    SPOK      9   23     950   4    100   30    3950   6
REVELSTOKE   KEL       9   20     550   0     51   29    1350   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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   S    9
CRANBROOK             VR   5   E   15

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1430 m         29 C
SPOKANE         1040 m         28 C

TODAY'S VENTING: BECOMING GOOD IN THE MID AFTERNOON.

VENTING FOR WEDNESDAY: GOOD

VENTING OUTLOOK THURSDAY THRU SATURDAY:

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.     45   19    1250   5    100   27    2950  10
PR. GEORGE   P.G.     27   17     900   9     62   26    1500  10
SMITHERS     P.G.     20   17     800   4     50   23    1250   7
WELLS GRAY   P.G.     42   19    1300  13    100   28    4000  20
FT NLSN      F.N.     20   18     550   6     87   24    1950   7
FT STJOHN    F.N.     27   20    1000   6     98   25    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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            S   15   S   28
SMITHERS              SW  11   S   28

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1380 m         28 C
FT. NELSON      1200 m         26 C

TODAY'S VENTING: FAIR BECOMING FAIR TO GOOD BY MID AFTERNOON.

VENTING FOR WEDNESDAY: GOOD

VENTING OUTLOOK THURSDAY THRU SATURDAY: FAIR TO GOOD AS THE AIRMASS
REMAINS UNSTABLE.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     57   19    1150   9     79   24    1350   9
FRASER VLY   QUIL     55   19    1150   9     87   26    1500   9
SRN VRISL    QUIL     51   19    1100   8     75   24    1250   8
CNTRL VRISL  QUIL     52   20     750   5     89   24    1600   9
NRN VRISL    HRDY     18   16     350   3     68   19    1450   6
TERRACE      ANT      59   17    1200   7    100   23    3200  12
STEWART      ANT      50   18     950   5    100   23    2400  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 TUESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W    9   SW   9   SW  24
PORT HARDY   W   11   S   17   S   26
SANDSPIT     S   26   S   26   S   31

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1600 m         25 C
PORT HARDY      1400 m         22 C
ANNETTE          150 m         12 C

TODAY'S VENTING: FAIR BECOMING GOOD BY NOON.

VENTING FOR WEDNESDAY: GOOD

VENTING OUTLOOK THURSDAY THRU SATURDAY:FAIR TO GOOD AS CONDITIONS
REMAIN UNSETTLED.

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

END/LM