FPCN39 CWLW 151400
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 15 APRIL 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      38    9     800   6    100   20    3200   7
KAMLOOPS     KEL      36    9     950   5    100   19    3350   7
OKANAGAN     KEL      25    6     650   6     73   16    2200   5
CASTLEGAR    SPOK     26    7     850   5    100   16    3500   6
CRANBROOK    SPOK      9    5     950   7    100   13    3950   7
REVELSTOKE   KEL      25    6     750   6     57   14    2000   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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
PENTICTON    VR   5   VR   5   E   15
CRANBROOK             VR   5   N   19

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: 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.     30    5    1400   5     97   14    2950   8
PR. GEORGE   P.G.     12    5     750   5     91   14    2550   8
SMITHERS     P.G.     11    4     650   2     57   12    1950   4
WELLS GRAY   P.G.     30    5    1400   5     97   14    2950   8
FT NLSN      F.N.      9    2     400   0     71   10    1350   9
FT STJOHN    F.N.      9    5     700  14     95   10    2450   9

*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            SE  15   S    9
SMITHERS              S   20   S    9

TODAY'S VENTING: GOOD

VENTING FOR FRIDAY: GOOD


COAST

           UPPER      ***** MORNING ******    ***** AFTERNOON ****
             AIR      VI  Tmp  MXG HT  Wnd    VI  Tmp  MXG HT  Wnd
                               (mASL)  (kt)            (mASL)  (kt)
VANCOUVER    QUIL      9    9     100  14     50   14     400  16
FRASER VLY   QUIL     51   14     400  16     74   22    1150   9
SRN VRISL    QUIL      9    9       0   7     47   14     400  13
CNTRL VRISL  QUIL      9    8      50   7     50   15     400  13
NRN VRISL    HRDY     25    8     300   6     61   15     700  10
TERRACE      ANT       9    6     200  10     97   12    1300  15
STEWART      ANT       9    7       0  10     95   12    1050  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 THURSDAY AFTERNOON (WINDS IN KM/H):
             900m     1800m    2700m
VANCOUVER    E   31   SE  33   SE  26
PORT HARDY   SE  30   S   44   S   37
SANDSPIT     S   61   S   67   S   76

TODAY'S VENTING: FAIR TO GOOD.

VENTING FOR FRIDAY: FAIR

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


END/
$$$$^^