138  
FXUS63 KLSX 151740  
AFDLSX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE SAINT LOUIS MO  
1140 AM CST SUN FEB 15 2026  
   
KEY MESSAGES  
 
- UNSEASONABLY WARM TEMPERATURES ARE FORECAST MONDAY THROUGH  
THURSDAY, POTENTIALLY THREATENING DAILY RECORDS ON WEDNESDAY.  
 
 
   
SHORT TERM  
(THROUGH LATE TONIGHT)  
ISSUED AT 237 AM CST SUN FEB 15 2026  
 
LIGHT RAIN MAY LINGER FIRST THING THIS MORNING IN PARTS OF  
SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS, BUT SHOULD MOVE OUT BY  
MID MORNING AS THE LOW-LEVEL CYCLONE SHIFTS EASTWARD INTO THE  
SOUTHEASTERN CONUS. SOME PATCHY DRIZZLE CANNOT BE RULED OUT BEHIND  
THE ACCUMULATING RAIN DUE TO LOW-LEVEL SATURATION AND WEAK NEAR-  
SURFACE CONVERGENCE. SOME PATCHY FOG HAS ALSO DEVELOPED IN  
NORTHEAST MISSOURI AND WEST-CENTRAL ILLINOIS WHERE MID/HIGH LEVEL  
CLOUDINESS HAS MOVED OFF TO THE SOUTHEAST. THE LOW STRATUS WILL  
ADVECT OUT OF THE REGION FROM NORTHWEST TO SOUTHEAST, WITH PARTS  
OF SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS NOT SEEING THE SUN  
UNTIL CLOSER TO ABOUT 2000 UTC. THIS MEANS THAT WE WILL HAVE A  
RATHER UNUSUAL SOUTHEAST (COOLER) TO NORTHWEST (WARMER)  
TEMPERATURE GRADIENT FOR THIS AFTERNOON'S HIGHS. READINGS SHOULD  
TOP OUT IN THE LOW 60S ACROSS PARTS OF NORTHEAST MISSOURI, WITH  
HIGHS ONLY IN THE LOW 50S FOR PARTS OF SOUTHEAST MISSOURI AND  
SOUTHWEST ILLINOIS.  
 
AT LEAST AREAS OF FOG SHOULD DEVELOP OVERNIGHT TONIGHT ACROSS  
SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS. THIS IS WHERE THE LOW  
STRATUS WILL DEPART LATEST TODAY, SO MORE LIMITED MIXING IS EXPECTED  
IN THOSE LOCATIONS. IN ADDITION, THIS AREA SAW QUITE A BIT OF  
RAINFALL OVER THE PAST 24 HOURS (0.75-1.50" FOR MOST) SO NEAR-  
SURFACE MOISTURE IS QUITE HIGH. FINALLY, FAVORABLE CONDITIONS FOR  
RADIATIONAL COOLING ARE FORECAST OVERNIGHT WITH A MOSTLY CLEAR SKY  
AND LIGHT WINDS NEAR A SURFACE RIDGE OF HIGH PRESSURE. SHORT-TERM  
MODEL GUIDANCE IS A BIT VARIABLE WITH HOW WIDESPREAD (AND DENSE) THE  
FOG WILL BE, BUT THERE IS A POSSIBILITY OF SEEING AT LEAST SOME  
PATCHY DENSE FOG IN OUR SOUTHEASTERN COUNTIES. HREF PROBABILITIES  
FOR VISIBILITIES AT OR BELOW 1/4SM ARE IN THE 50-60+% RANGE. FOR  
NOW, DID ADD PATCHY DENSE FOG MENTION BUT WE WILL HAVE TO MONITOR  
THE POSSIBILITY FOR MORE WIDESPREAD DENSE FOG, WHICH WOULD  
NECESSITATE A DENSE FOG ADVISORY. OUTSIDE OF THE FOG CHANCES, A  
QUIET SEASONABLY MILD NIGHT IS ON TAP WITH LOWS RANGING FROM THE MID  
30S TO LOW 40S. SIMILAR TO TODAY'S EXPECTED HIGHS, WARMEST READINGS  
SHOULD BE IN NORTHEAST MISSOURI WITH COOLER TEMPERATURES FURTHER TO  
THE SOUTHEAST.  
 
GOSSELIN  
 
 
   
LONG TERM  
(MONDAY THROUGH SATURDAY)  
ISSUED AT 237 AM CST SUN FEB 15 2026  
 
(MONDAY - THURSDAY NIGHT)  
 
A WARMING TREND BEGINS ON MONDAY AS WINDS TURN OUT OF THE SOUTHWEST  
AT LOWER LEVELS OF THE TROPOSPHERE. STRONG LOW-LEVEL WARM AIR  
ADVECTION COMBINED WITH PARTIAL SUNSHINE IS EXPECTED TO COMBINE TO  
YIELD HIGH TEMPERATURES IN THE 60S AREAWIDE. THESE READINGS WOULD BE  
NEARLY 20 DEGREES ABOVE NORMAL FOR THE DATE.  
 
THERE REMAINS STRONG CONFIDENCE IN WELL-ABOVE NORMAL TEMPERATURES  
CONTINUING THROUGH THE DAY ON THURSDAY. THERE REMAINS SOME  
UNCERTAINTY AS TO WHICH OF WEDNESDAY OR THURSDAY WILL BE THE WARMER  
OF THE TWO, BUT REGARDLESS, HIGHS IN THE MID 60S TO LOW 70S APPEAR  
LIKELY. PROBABILITIES FOR HIGHS OF 70+ FROM THE NBM ARE NOW SIMILAR  
EACH OF THESE AFTERNOONS, WITH THE HIGHEST CHANCES (60-90%)  
ALONG/SOUTH OF I-70. SIMILAR TO YESTERDAY, BOTH THE 75TH AND THE  
90TH PERCENTILES THOUGH ARE ABOUT 1-2 DEGREES HIGHER ACROSS MOST OF  
THE AREA ON THURSDAY, SO THERE MAY BE A BIT MORE POTENTIAL ON  
THURSDAY COMPARED TO WEDNESDAY. REGARDLESS, IT WILL BE VERY WARM FOR  
THE MIDDLE OF FEBRUARY AS EVEN THE 25TH PERCENTILE OF THE NBM EACH  
DAY IS 20-25+ DEGREES ABOVE NORMAL. WEDNESDAY STILL HAS THE BEST  
CHANCE OF POTENTIALLY SEEING RECORDS, MAINLY DUE TO THE FACT THAT  
WEDNESDAY'S RECORD HIGHS ARE SEVERAL DEGREES COOLER COMPARED TO  
THURSDAY. PLEASE SEE THE CLIMATE SECTION BELOW FOR MORE DETAILS.  
 
MUCH OF THE UPCOMING WEEK LOOKS DRY, WITH LITTLE/NO SIGNAL FOR ANY  
WIDESPREAD RAINFALL. A PSEUDO-DRYLINE MOVES THROUGH THE REGION LATE  
TUESDAY NIGHT, BRINGING A LOW CHANCE (20-30%) OF SHOWERS. MODEL  
GUIDANCE ALSO IS HINTING AT SOME ELEVATED INSTABILITY, SO ALSO COULD  
NOT RULE OUT A THUNDERSHOWER. A COLD FRONT IS FORECAST TO MOVE  
THROUGH THE BI-STATE AREA LATE THURSDAY/THURSDAY NIGHT. MOISTURE  
RETURN AHEAD OF THIS BOUNDARY LOOKS WEAK/SUSPECT, AS SURFACE  
DEWPOINTS LOOK TO STRUGGLE TO GET BACK CLOSE TO THE 50 DEGREE MARK  
EAST OF THE MISSISSIPPI RIVER. THE STRONGER MID/UPPER LEVEL FORCING  
FOR ASCENT ALSO STAYS OVER THE UPPER MIDWEST. THIS MEANS THAT THERE  
IS THE POTENTIAL FOR THIS FRONT TO MOVE THROUGH MOSTLY DRY. LREF  
PROBABILITIES OVER THE 24-HOUR PERIOD ENDING AT 1200 UTC FRIDAY TOP  
OUT AT 40-60% ALONG/EAST OF THE MISSISSIPPI RIVER. ENSEMBLE GUIDANCE  
ALSO SUGGESTS SOME POTENTIAL FOR WEAK (>250 J/KG) SURFACE-BASED  
INSTABILITY AS THE GEFS+GEPS HAS PROBABILITIES THURSDAY  
AFTERNOON/EVENING IN THE 10-20% RANGE IN SOUTH CENTRAL AND SOUTHWEST  
ILLINOIS.  
 
(FRIDAY - SATURDAY)  
 
MUCH COOLER TEMPERATURES ARE FORECAST TO END THE WEEK INTO NEXT  
WEEKEND. HOWEVER, THE INCOMING AIR MASS LOOKS LIKE ONE THAT WILL GET  
US CLOSER TO NORMAL LEVELS AND NOT ANY REAL COLD AIR WITH BITE.  
MOSTLY DRY WEATHER IS ALSO FAVORED, THOUGH WE WILL HAVE TO WATCH A  
TRAILING MIDLEVEL SHORTWAVE TROUGH MOVING ACROSS THE REGION LATE  
FRIDAY/FRIDAY NIGHT. THIS FEATURE MAY HELP YIELD SOME LIGHT  
PRECIPITATION DURING THIS TIME PERIOD (MOST LIKELY A COLD RAIN). THE  
BEST SIGNAL FOR ANY MEASURABLE PRECIPITATION AT THIS TIME APPEARS TO  
BE ACROSS SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS WHERE LREF  
PROBABILITIES ARE IN THE 20-30% RANGE ENDING SATURDAY MORNING.  
 
GOSSELIN  
 
 
   
AVIATION  
(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)  
ISSUED AT 1140 AM CST SUN FEB 15 2026  
 
FLIGHT CONDITIONS CONTINUE TO IMPROVE ACROSS THE REGION AS  
STRATOCUMULUS ERODES. GIVEN THE NON-UNIFORM CLEARING OF CLOUDS, IT  
IS STILL UNCERTAIN EXACTLY WHEN EACH TERMINAL WILL HAVE VFR FLIGHT  
CONDITIONS PREVAIL BUT IT IS MOST LIKELY TO BE BY MID-AFTERNOON.  
CONDITIONS WILL BE FAVORABLE FOR AT LEAST PATCHY FOG AND LOW STRATUS  
ACROSS PORTIONS OF THE AREA TONIGHT, WITH THE HIGHEST CHANCES ACROSS  
SOUTHEASTERN MO/SOUTHWESTERN IL AND RIVER VALLEYS ACROSS EAST-  
CENTRAL MO. THEREFORE, MVFR TO IFR FLIGHT CONDITIONS HAVE BEEN  
INCLUDED AT KSUS AND KCPS. ANY FOG AND LOW STRATUS WILL DISSIPATE  
THROUGH SUNRISE MONDAY WITH SOUTHERLY WINDS INCREASING AS WELL.  
 
PFAHLER  
 
 
   
CLIMATE  
 
ISSUED AT 232 AM CST SAT FEB 14 2026  
 
DAILY RECORD HIGH TEMPERATURES MAY BE THREATENED EARLY/MID NEXT  
WEEK. HERE ARE RECORDS BETWEEN TUESDAY 2/17 AND THURSDAY 2/19 AT OUR  
THREE OFFICIAL CLIMATE STATIONS:  
 
TUESDAY 2/17 WEDNESDAY 2/18 THURSDAY 2/19  
KSTL 77/1911 74/1971 77/2016  
KCOU 74/2011 71/2017 77/2017  
KUIN 72/2017 68/2017 72/2017  
 
 
   
LSX WATCHES/WARNINGS/ADVISORIES  
 
MO...NONE.  
IL...NONE.  
 
 
 
 
WFO LSX  
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