FPCN39 CWLW 271443 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 Tuesday 27 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 17 1000 4 88 22 2250 6 KAMLOOPS KEL 63 18 1650 5 83 23 2750 7 OKANAGAN KEL 36 16 1150 4 88 21 2400 6 CASTLEGAR SPOK 29 14 950 5 52 19 2300 3 CRANBROOK SPOK 29 13 1050 5 51 19 2650 3 REVELSTOKE KEL 32 15 1100 4 86 20 2400 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 TUESDAY AFTERNOON (WINDS IN KM/H): 900m 1800m 2700m PENTICTON VR 5 SW 9 SW 17 CRANBROOK VR 5 W 15 INVERSION HT BREAKTHRU TEMP KELOWNA 800 m 16 C SPOKANE 1000 m 15 C TODAY'S VENTING: BEOCMING GOOD BY NOON EXCEPT FAIR IN THE SOUTHEAST. VENTING FOR WEDNESDAY: GOOD VENTING OUTLOOK THURSDAY THRU SATURDAY: FAIR TO GOOD AS THE COOLER AIR MOVES IN FROM THE WEST AT HIGHER LEVELS DESTABILIZING THE AIRMASS. 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. 44 14 1750 5 100 19 3950 8 PR. GEORGE P.G. 45 13 1250 7 100 20 3700 8 SMITHERS P.G. 9 11 600 3 100 20 3500 7 WELLS GRAY P.G. 50 14 1850 6 100 20 4000 8 FT NLSN F.N. 73 7 1700 7 81 10 185 0 7 FT STJOHN F.N. 59 3 1600 7 66 6 1750 7 *SUBTRACT 20 FROM THE VENTILATION INDEX IN VALLEYS IF THE MIXING HEIGHT IS BELOW THE HEIGHT OF THE LOCAL HILLS. FORECAST UPPER WINDS FOR TUESDAY AFTERNOON (WINDS IN KM/H): 900m 1800m 2700m PR. GEORGE S 9 SE 13 SMITHERS S 19 S 13 INVERSION HT BREAKTHRU TEMP PR. GEORGE 1370 m 18 C FT. NELSON 2600 m 20 C TODAY'S VENTING: GOOD BY THIS AFTERNOON AS THE AIRMASS DESTABILIZES. VENTING FOR WEDNESDAY: FAIR TO GOOD. VENTING OUTLOOK THURSDAY THRU SATURDAY: FAIR TO GOOD AS UNSTABLE AIRMASS LIES OVER THE REGION. COAST UPPER ***** MORNING ****** ***** AFTERNOON **** AIR VI Tmp MXG HT Wnd VI Tmp MXG HT Wnd (mASL) (kt) (mASL) (kt) VANCOUVER QUIL 16 15 200 5 69 18 1100 9 FRASER VLY QUIL 19 16 250 5 88 20 1100 11 SRN VRISL QUIL 17 15 200 5 55 18 1100 6 CNTRL VRISL QUIL 19 16 250 5 83 20 1100 10 NRN VRISL HRDY 18 13 250 4 56 17 800 10 TERRACE ANT 17 15 300 5 80 22 1500 8 STEWART ANT 19 16 300 6 90 22 1500 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 TUESDAY AFTERNOON (WINDS IN KM/H): 900m 1800m 2700m VANCOUVER S 15 S 24 SW 26 PORT HARDY S 30 S 33 S 35 SANDSPIT S 39 S 41 S 44 INVERSION HT BREAKTHRU TEMP QUILLAYUTE 300 m 17 C PORT HARDY 400 m 16 C ANNETTE 250 m 15 C TODAY'S VENTING: GENERALLY GOOD. VENTING FOR WEDNESDAY: GOOD VENTING OUTLOOK THURSDAY THRU SATURDAY: GOOD TIL FRIDAY WHEN A SURFACE RIDGE MAY STABILIZE THE AIRMASS AND GIVE ONLY FAIR VENTING. VENTILATION GUIDELINES: 0-33.....POOR 34-54.....FAIR 55-100.....GOOD. VENTILATION INDICES NORMALLY DROP TO POOR AFTER SUNSET. END/MWSO