FPCN39 CWLW 271400
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 27 MAY 1999 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      20   13     600   8     77   20    1250  15
KAMLOOPS     KEL      12   12     500   5     60   22    1700  10
OKANAGAN     KEL      12   12     500   5     52   20    1250   8
CASTLEGAR    SPOK     12   12     600   5     44   20    1200   5
CRANBROOK    SPOK     15   10     950   5     78   20    2000  10
REVELSTOKE   KEL      12   12     600   5     42   18    1300   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    SW  13   SW  30   SW  48
CRANBROOK             SW  17   SW  35

TODAY'S VENTING: FAIR


VENTING FOR FRIDAY: POOR


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     9     950   5     100   13    2800  20
PR. GEORGE   P.G.     9     8     680   3      94   12    2000  12
SMITHERS     P.G.     9     5     550   5      69   12    1600   8
WELLS GRAY   P.G.     9     3    1000   5     100   13    2950  24
FT NLSN      F.N.     20   13     400   2     100   17    3400  10
FT STJOHN    F.N.     20   13     700   4     100   15    3700  12

*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  20   W   31
SMITHERS              SW  30   SW  31

TODAY'S VENTING: GOOD THIS AFTERNOON WITH THE PASSAGE OF THE COLD
FRONT.

VENTING FOR FRIDAY: POOR


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL     15   13     300   4     65   17     950   9
FRASER VLY   QUIL     12   12     200   4     69   18    1000   9
SRN VRISL    QUIL     20   13     100   4     46   17     950   5
CNTRL VRISL  QUIL     20   13     100   4     56   17     900   7
NRN VRISL    HRDY     11   10     100   4     70   13    1350  15
TERRACE      ANT       9    7     700   5     70   10    1600  12
STEWART      ANT       9    8     400   4     70   10    1100  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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    W   19   W   31   W   46
PORT HARDY   W   20   W   24   W   35
SANDSPIT     W   33   W   39   W   39

TODAY'S VENTING: BECOMING GOOD IN THE NORTHWEST BY THIS AFTERNOON.
FAIR TO GOOD IN THE SOUTH LATE THIS AFTERNOON.

VENTING FOR FRIDAY: POOR


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


END/LM
$$$$^^