FPCN39 CWLW 071354
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 TUESDAY 7 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       9   22     500   0     74   30    2050   5
KAMLOOPS     KEL       9   22     550   0     98   31    2900   7
OKANAGAN     KEL       9   21     550   0    100   32    3350   7
CASTLEGAR    SPOK      9   22     800   0     83   30    2800   5
CRANBROOK    SPOK      9   19     950  11    100   27    3950   6
REVELSTOKE   KEL       9   20     550   0     59   26    1650   5

*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   SW  11   SW  17
CRANBROOK             VR   5   SW  15

           INVERSION HT    BREAKTHRU TEMP
KELOWNA          300 m         21 C
SPOKANE          400 m         24 C

TODAY'S VENTING:

VENTING FOR WEDNESDAY: GOOD.

VENTING OUTLOOK THURSDAY THRU 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.     35   16    1300  10    100   22    2950  12
PR. GEORGE   P.G.      9   17     700   7    100   22    2200  13
SMITHERS     P.G.     13   17     650   3    100   24    2350  12
WELLS GRAY   P.G.     28   18    1850  16    100   22    4000  16
FT NLSN      F.N.      9   18     400  17     95   25    1100  15
FT STJOHN    F.N.      9   17     700  18    100   26    2650  15

*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            W   19   SW  31
SMITHERS              W   15   W   31

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       500 m         17 C
FT. NELSON       450 m         18 C

TODAY'S VENTING: GOOD. DATA BASED ON FORT NELSON SOUNDING.

VENTING FOR WEDNESDAY: GOOD.

VENTING OUTLOOK THURSDAY THRU SATURDAY: GOOD.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     39   18     750   5     51   22    1350   4
FRASER VLY   QUIL     49   20    1000   5     62   26    1900   4
SRN VRISL    QUIL     24   17     550   3     48   22    1300   4
CNTRL VRISL  QUIL     24   17     550   3     61   26    1850   4
NRN VRISL    HRDY      9   12       0   3     55   20    1200   6
TERRACE      ANT      67   13    1150   9    100   20    3200  11
STEWART      ANT      64   14     900   8    100   20    2250  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   17   W   13   W   19
PORT HARDY   NW  24   NW  30   W   30
SANDSPIT     SW  26   SW  22   SW  28

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       500 m         17 C
PORT HARDY      1500 m         20 C
ANNETTE          150 m         14 C

TODAY'S VENTING: GOOD.

VENTING FOR WEDNESDAY: GOOD

VENTING OUTLOOK THURSDAY THRU SATURDAY: GOOD.

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

END/MWSO