FPCN39 CWLW 291430
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 Thursday 29 May 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      36   21    1000   3     90   26    2550   5
KAMLOOPS     KEL      35   20    1100   3    100   26    3350   5
OKANAGAN     KEL      30   19     950   3     84   24    2450   5
CASTLEGAR    SPOK     17   15     750   3     73   22    2250   5
CRANBROOK    SPOK     41   15    1550   5    100   22    3950   5
REVELSTOKE   KEL      12   16     550   3     62   22    2100   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    W    9   W   20   W   35
CRANBROOK             SW   9   SW  26

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1000 m         18 C
SPOKANE         1200 m         17 C

TODAY'S VENTING: GOOD.

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: 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.     45   15    1500   5    100   19    3950   10
PR. GEORGE   P.G.     21   14     950   5     80   18    2500   8
SMITHERS     P.G.     15   13     700   5    100   19    3000   8
WELLS GRAY   P.G.     50   15    1600   5    100   20    4000   8
FT NLSN      F.N.     18   14     500   5    100   19    3400   8
FT STJOHN    F.N.     55   14    1500   5    100   19    3700   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PR. GEORGE            SW  11   S   17
SMITHERS              W   15   W   17

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1500 m         18 C
FT. NELSON       600 m         14 C

TODAY'S VENTING: GOOD.

VENTING FOR FRIDAY: GOOD.

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD.

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      5   15     100   0     50   19    1000   5
FRASER VLY   QUIL     10   15     200   5    100   22    3000  16
SRN VRISL    QUIL      0   14     100   0     65   20    1350   5
CNTRL VRISL  QUIL      0   15     100   0     65   20    1350   5
NRN VRISL    HRDY      0   13     100   0     30   17     600   5
TERRACE      ANT       0   10     100   0     80   19    2550   5
STEWART      ANT       0   10     100   0     60   19    1850   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    SW  15   SW  20   W   28
PORT HARDY   NW  13   W   13   SW  20
SANDSPIT     NW  19   W   13   SW  20

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      3000 m         30 C
PORT HARDY      1200 m         21 C
ANNETTE         2000 m         20 C

TODAY'S VENTING: POOR COASTAL. FAIR TO GOOD INLAND.

VENTING FOR FRIDAY: FAIR.

VENTING OUTLOOK SATURDAY THRU MONDAY: FAIR.

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

END/KJ