FPCN39 CWLW 271432
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 Sunday 27 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      34   21    1000   3     80   31    3200   4
KAMLOOPS     KEL      34   21    1150   3     80   30    3350   4
OKANAGAN     KEL      29   19    1000   3     80   30    3350   4
CASTLEGAR    SPOK     28   19     950   5     92   29    3500   5
CRANBROOK    SPOK      9   18     950   9     93   27    3950   5
REVELSTOKE   KEL      20   17     900   3     66   25    2350   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   VR   5
CRANBROOK             VR   5   SE  11

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1600 m         23 C
SPOKANE         1200 m         23 C

TODAY'S VENTING: Poor this morning becoming good in the early
afternoon.

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY: Poor in the morning
becoming good in the early afternoon with daytime heating.

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.     41   17    1800   8     98   24    3950   6
PR. GEORGE   P.G.     29   14     900  10    100   22    3700   7
SMITHERS     P.G.     32   16     900   7    100   23    3500   6
WELLS GRAY   P.G.      9   15    1000   8     98   24    4000   6
FT NLSN      F.N.      9   17     400   4     63   24    2700   3
FT STJOHN    F.N.      9   15     700   3     57   21    2700   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 SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            E   11   SE  15
SMITHERS              SE  19   SE  15

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1040 m         20 C
FT. NELSON      1400 m         18 C

TODAY'S VENTING: Poor this morning becoming good in the early
afternoon.

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY:Poor in the mornings
becoming good in the afternoons with daytime heating.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     22   19     750   2     26   23     950   2
FRASER VLY   QUIL     23   20     800   2     55   28    1950   3
SRN VRISL    QUIL      9   18     700   0     49   24    1250   5
CNTRL VRISL  QUIL      9   20     750   0     49   26    1500   5
NRN VRISL    HRDY     17   15     100   8     48   19     950   6
TERRACE      ANT      47   17    1050   6    100   22    2250  11
STEWART      ANT      14   16     400   1     92   22    1850   8

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

FORECAST UPPER WINDS FOR SUNDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    VR   5   S    9   S   19
PORT HARDY   VR   5   S   22   S   31
SANDSPIT     VR   5   SE  26   SE  37

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE       975 m         22 C
PORT HARDY      1500 m         22 C
ANNETTE          800 m         17 C

TODAY'S VENTING: Poor on the southcoast to fair in the north
this morning beocming fair in the south good in the north.

VENTING FOR MONDAY: GOOD

VENTING OUTLOOK TUESDAY THRU THURSDAY: Poor in the mornings
becoming good in the afternoons with daytime heating.

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

END/lm