FPCN39 CWLW 061320
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 6 MAY 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      32   23     950   3    100   31    3200   6
KAMLOOPS     KEL      21   20     800   3    100   31    3350   6
OKANAGAN     KEL       9   16     550   0     74   28    2000   6
CASTLEGAR    SPOK     20   17     800   4    100   28    3500   8
CRANBROOK    SPOK      9   16     950  13    100   26    3950   8
REVELSTOKE   KEL       9   16     550   0     64   26    1750   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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   W   11   W   13
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1460 m         26 C
SPOKANE         1020 m         22 C

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: GOOD

VENTING OUTLOOK FRIDAY THRU SUNDAY: 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.      9   14     950  13    100   25    3950  18
PR. GEORGE   P.G.     16   12     850   5    100   22    3700  16
SMITHERS     P.G.     19   15     850   3     55   20    1150  10
WELLS GRAY   P.G.      9   13    1000  13    100   23    4000  18
FT NLSN      F.N.     35   13     550  16     78   17     950  19
FT STJOHN    F.N.     43   13     850  22    100   21    3700  21

*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            SW  24   SW  39
SMITHERS              SW  30   SW  39

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE      1200 m         19 C
FT. NELSON      1130 m         21 C

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: GOOD

VENTING OUTLOOK FRIDAY THRU SUNDAY: GOOD

COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     48   15     800   6     57   19    1000   7
FRASER VLY   QUIL     50   16     850   6     63   21    1150   7
SRN VRISL    QUIL     45   13     750   6     55   19     950   6
CNTRL VRISL  QUIL     49   17     900   6     63   22    1200   6
NRN VRISL    HRDY     48   12     850   6     55   15     950   7
TERRACE      ANT     100   15    2100  15    100   20    2950  18
STEWART      ANT     100   14    1600  12    100   20    2600  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 WEDNESDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W    9   VR   5   SW  19
PORT HARDY   NW  15   W   19   SW  37
SANDSPIT     SW  30   SW  39   SW  59

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1650 m         27 C
PORT HARDY      1620 m         26 C
ANNETTE         NONE

TODAY'S VENTING: GOOD

VENTING FOR THURSDAY: GOOD

VENTING OUTLOOK FRIDAY THRU SUNDAY: GOOD

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


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