845
FNUS73 KLSX 120906
FWSLSX
SPOT FORECAST FOR HS UNIT...MISSOURI DEPARTMENT OF CONSERVATION
NATIONAL WEATHER SERVICE SAINT LOUIS MO
306 AM CST THU DEC 12 2024
FORECAST IS BASED ON IGNITION TIME OF 1100 CST ON DECEMBER 12.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE
NATIONAL WEATHER SERVICE.
DISCUSSION
A WARM FRONT WILL LIFT NORTH THROUGH THE AREA THIS MORNING, STALLING
TO THE NORTH OF THE BURN. SOUTHERLY FLOW WILL CONTINUE THROUGH THE
DAY. DESPITE WARMING INTO THE LOW 50S, MIXING HEIGHTS WILL BE MUCH
LOWER THAN YESTERDAY, ONLY AROUND 2,000 FT. FLOW WITHIN THIS MIXED
LAYER WILL BE IN THE TEENS AND FROM THE SOUTH. THE WEAKER LOW-LEVEL
FLOW AND MIXING HEIGHTS DECREASES CONFIDENCE IN EFFECTIVE SMOKE
DISPERSION.
MINIMUM RH VALUES THIS AFTERNOON WILL BE IN THE UPPER 40S, THOUGH
IF WE WARM A LITTLE MORE THAN CURRENTLY FORECAST, AFTERNOON RH VALUES
COULD BE A LITTLE LOWER.
REST OF TODAY
SKY/WEATHER.........SUNNY (20-30 PERCENT).
CHANCE OF PCPN......0 PERCENT.
LAL.................NO TSTMS.
TEMPERATURE.........38 AT IGNITION...MAX 49.
RH..................50 PERCENT AT IGNITION...MIN 43 PERCENT.
WIND (20 FT)........WINDS SOUTHEAST AT 6 MPH AT
IGNITION...OTHERWISE SOUTHEAST WINDS 5 TO 6
MPH.
EYE LEVEL WINDS.....2 MPH USING AN ADJUSTMENT FACTOR OF 0.3.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
FIRE GROWTH AT IGNITION...MAX 4.
MIXING HEIGHT.......2000 FT AGL AT IGNITION...OTHERWISE MAX 2500 FT
AGL.
TRANSPORT WINDS.....SOUTH 9 TO 14 MPH SHIFTING TO THE EAST 7 TO 8
MPH LATE IN THE AFTERNOON.
SMOKE DISPERSAL.....POOR /3770 M/S-M/ AT IGNITION. MAX...POOR /3940
M/S-M/.
TIME (CST) 11 AM 1 PM 3 PM 5 PM 7 PM 9 PM
SKY (%).........42 14 5 10 14 24
WEATHER COV.....
WEATHER TYPE....NONE NONE NONE NONE NONE NONE
TSTM COV........
CWR.............0 0 0 0 0 0
LAL.............1 1 1 1 1 1
TEMP............38 46 49 40 35 32
RH..............50 43 44 62 66 69
20 FT WIND......SE 6 S 6 SE 5 E 5 E 5 NE 5
20 FT WIND GUST.11 11 10 10 9 7
EYE LEVEL WIND..SE 3 S 3 SE 2 E 2 E 2 NE 2
EYE LVL WND GST.5 5 5 5 4 3
MIX HGT (KFT)...2.0 2.5 1.7 0.5 0.5 0.6
TRANSPORT WIND..S 14 S 10 S 9 E 8 E 9 E 9
HAINES INDEX....4 4 4 4 4 4
VRATE KT-FT/1K..24 23 13 4 4 5
VENTRATE CAT....POOR POOR POOR POOR POOR POOR
TONIGHT
SKY/WEATHER.........PARTLY CLOUDY (25-35 PERCENT) THEN BECOMING
MOSTLY CLOUDY (50-60 PERCENT).
CHANCE OF PCPN......0 PERCENT.
LAL.................NO TSTMS.
TEMPERATURE.........MIN 26.
RH..................MAX 78 PERCENT.
WIND (20 FT)........NORTHEAST WINDS AROUND 5 MPH IN THE EVENING AND
OVERNIGHT BECOMING LIGHT, THEN BECOMING EAST
AROUND 5 MPH AFTER 3 AM.
EYE LEVEL WINDS.....2 MPH USING AN ADJUSTMENT FACTOR OF 0.3.
HAINES INDEX........3 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE
PLUME DOMINATED FIRE GROWTH.
MIXING HEIGHT.......MIN 500 FT AGL.
TRANSPORT WINDS.....EAST 8 TO 9 MPH.
SMOKE DISPERSAL.....POOR (600 M/S-M).
FRIDAY
SKY/WEATHER.........PARTLY SUNNY (60-70 PERCENT).
CHANCE OF PCPN......10 PERCENT.
LAL.................NO TSTMS.
TEMPERATURE.........MAX 50.
RH..................MIN 48 PERCENT.
WIND (20 FT)........SOUTHEAST WINDS 5 TO 8 MPH.
EYE LEVEL WINDS.....2-3 MPH USING AN ADJUSTMENT FACTOR OF 0.3.
HAINES INDEX........3 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE
PLUME DOMINATED FIRE GROWTH.
MIXING HEIGHT.......MAX 1900 FT AGL.
TRANSPORT WINDS.....EAST 9 TO 12 MPH SHIFTING TO THE SOUTHEAST 13
TO 16 MPH LATE IN THE MORNING.
SMOKE DISPERSAL.....POOR (860 M/S-M).
FORECASTER...DELIA
REQUESTED BY...DAVID SHIEH
TYPE OF REQUEST...PRESCRIBED
.TAG 2428422.0/LSX
.DELDT 12/12/24
.FORMATTERVERSION 2.0.0
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page