FPCN39 CWLW 071322
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 THURSDAY 7 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      40   20     950   5     79   26    2300   5
KAMLOOPS     KEL      33   18     950   5     82   26    2500   5
OKANAGAN     KEL      33   18     950   5    100   27    3350   6
CASTLEGAR    SPOK     48   18     950  10    100   27    3500  14
CRANBROOK    SPOK     23   17    1050  13    100   25    3950  15
REVELSTOKE   KEL      26   16     800   5     80   25    2500   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    VR   5   W    9   SW   9
CRANBROOK             VR   5   VR   5

           INVERSION HT    BREAKTHRU TEMP
KELOWNA         1005 m         18 C
SPOKANE         1300 m         24 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.    100   15    3950  23    100   23    3950  23
PR. GEORGE   P.G.    100   11    1850  25    100   19    3700  25
SMITHERS     P.G.     29   10     700  14    100   17    2700  22
WELLS GRAY   P.G.    100   13    2750  23    100   21    4000  23
FT NLSN      F.N.    100   13    1500  21    100   17    3400  19
FT STJOHN    F.N.    100   12    3700  19    100   17    3700  19

*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            W   17   SW  24
SMITHERS              W   17   W   24

           INVERSION HT    BREAKTHRU TEMP
PR. GEORGE       690 m         10 C
FT. NELSON       430 m         11 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     85   15    1150  11     88   18    1200  12
FRASER VLY   QUIL     85   15    1150  11     89   19    1250  12
SRN VRISL    QUIL     82   15    1150  10     84   18    1200  10
CNTRL VRISL  QUIL     81   15    1150  10     86   19    1250  10
NRN VRISL    HRDY     46   10     450  11     97   13    1450  11
TERRACE      ANT     100   10    2000  11    100   14    3200  14
STEWART      ANT     100   11    1700  10    100   14    3000  13

*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    W   13   W   13   SW  19
PORT HARDY   NW  19   VR   5   SW  22
SANDSPIT     W   19   W   19   W   22

           INVERSION HT    BREAKTHRU TEMP
QUILLAYUTE      1480 m         22 C
PORT HARDY      NONE
ANNETTE         NONE

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD

VENTING OUTLOOK SATURDAY THRU MONDAY: GOOD

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


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