084  
FXUS64 KFWD 201712  
AFDFWD  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE FORT WORTH TX  
1212 PM CDT MON AUG 20 2018  
 
   
UPDATE
 
 
FRONT IS MOVING THROUGH THE AREA AND HAVE REFRESHED THE FORECAST  
TO ACCOUNT FOR CURRENT TRENDS AND TO HIGHLIGHT THE BEST CHANCES  
OF RAIN ACROSS THE SOUTHEAST ZONES THIS AFTERNOON. SOME OF THESE  
STORMS COULD PRODUCE DAMAGING WINDS. REST OF FORECAST IS ON TRACK.  
 
TR.92  
 

 
   
AVIATION
 
 
FOR METROPLEX SITES...VFR WILL PREVAIL THROUGH THE PERIOD WITH  
N/NW FLOW NEAR 10 KNOTS TODAY, DIMINISHING AFTER SUNSET. NORTH  
WINDS NEAR 5 KNOTS WILL PREVAIL TUESDAY MORNING, BECOMING MORE  
EASTERLY IN THE AFTERNOON. OTHERWISE SKIES WILL BE MOSTLY CLEAR  
WITH JUST SOME SOME HIGH CLOUDS. SMOKE FROM NORTHWESTERN US AND  
WESTERN CANADA SHOULD REMAIN MAINLY TO THE NORTH OF THE REGION AND  
WILL LIKELY NOT BE DENSE ENOUGH TO RESULT IN MVFR VISIBILITY  
RESTRICTIONS HERE BUT IT MAY BE SOMETHING TO MONITOR.  
 
FOR WACO, THE FRONT IS MOVING THROUGH NOW, SO THIS MEANS BEST  
THREAT FOR CONVECTION SHOULD BE SOUTH OF THE TAF SITES THIS  
AFTERNOON. WILL KEEP MENTION OF STORMS OUT OF TAF BUT WILL  
CONTINUE TO MONITOR. OTHERWISE VFR WITH NORTH/NORTHWESTERLY WINDS  
AT 5-10 KNOTS WILL PREVAIL THROUGH THIS EVENING, BUT WILL BECOME  
LIGHT AND VARIABLE OVERNIGHT.  
 
TR.92  
 

 
 
   
SHORT TERM
 
/ISSUED 406 AM CDT MON AUG 20 2018/  
/TODAY AND TONIGHT/  
 
THE MAIN CONCERN IN THE SHORT TERM FORECAST WILL REVOLVE AROUND  
RAIN CHANCES AND TEMPERATURES. IT APPEARS THAT CENTRAL TEXAS WILL  
HAVE THE BEST OPPORTUNITY FOR SHOWERS AND A FEW STORMS THIS  
MORNING AND INTO THE AFTERNOON. WHILE THE TEMPERATURE CONTRAST  
ACROSS THE FRONT WILL REMAIN LOW, NORTH WINDS WILL USHER IN DRIER  
AIR--MAKING IT FEEL A BIT MORE PLEASANT FOR NORTH TEXAS. CENTRAL  
TEXAS WILL LIKELY SEE ANOTHER DAY OF HOT CONDITIONS.  
 
A COUPLE OF OUTFLOW BOUNDARIES WERE NOTED THIS MORNING ACROSS  
PARTS OF NORTH AND CENTRAL TEXAS. MOST OF THESE BOUNDARIES REMAIN  
IN RESPONSE TO CONVECTION THAT OCCURRED ON SUNDAY AND AGAIN EARLY  
THIS MORNING. THE MAIN SYNOPTIC FRONT WAS ACTUALLY BEING SAMPLED  
BY THE WSR-88D NETWORK AND WAS LOCATED NEAR THE I-44 CORRIDOR AS  
OF 330 AM. WHILE THE TEMPERATURE GRADIENT ALONG THE FRONT IS  
QUITE WEAK, THERE IS NEARLY A 7-8 DEGREE CHANGE IN THE DEWPOINT  
TEMPERATURE, WITH MID TO UPPER 50S DEGREE DEWPOINTS ACROSS  
WESTERN OKLAHOMA. THROUGH THE DAY THIS DRIER AIR SHOULD SPILL  
SOUTHWARD AS THE SURFACE PRESSURE GRADIENT UPSTREAM TIGHTENS ON  
THE BACKSIDE OF A LOW ACROSS THE MISSOURI RIVER VALLEY. AS THE  
FRONT ADVANCES, THERE WILL THEORETICALLY BE A THREAT FOR SHOWERS  
AND A FEW THUNDERSTORMS ALONG AND AHEAD OF THE BOUNDARY WHERE  
SURFACE DEWPOINTS REMAIN IN THE UPPER 60S TO LOW 70S.  
ADDITIONALLY, POCKETS OF BETTER CONVERGENCE MAY EXIST WHERE THE  
MAIN FRONT INTERACTS WITH OUTFLOW BOUNDARIES. I'VE CARRIED A 15  
POP WITH A MENTION OF SHOWERS AND AN ISOLATED THUNDERSTORM OR TWO  
FOR MOST AREAS TO ADDRESS THIS POTENTIAL FOR RAIN/STORMS. MOST  
AREAS WITHIN THE 15 POP WILL REMAIN RAIN-FREE. THE BETTER RISK FOR  
MORE CONCENTRATED RAIN/THUNDER ACTIVITY, HOWEVER, WILL ACTUALLY  
BE ACROSS CENTRAL TEXAS WHERE A MODEST CONVEYOR OF ISENTROPIC  
ASCENT ALONG THE 300 K THETA SURFACE IS FORECAST.  
 
THE FRONT SHOULD SWEEP THROUGH MOST AREAS BY THIS AFTERNOON,  
EXCEPT FOR CENTRAL TEXAS. RAIN/THUNDER CHANCES WILL REMAIN  
HIGHEST HERE (AROUND 20 TO 30 PERCENT) IN THE AFTERNOON. THERE  
WILL BE A RISK FOR STRONG TO NEAR-SEVERE STORMS GIVEN THE LARGE  
DCAPE VALUES AND HOT CONDITIONS. THE VEERED LOW LEVEL FLOW AHEAD  
OF THE FRONT WILL BE THE MAIN CULPRIT FOR THESE HOT CONDITIONS AND  
AFTERNOON HIGHS SHOULD CLIMB INTO THE UPPER 90S TO NEAR 100  
DEGREES. HEAT INDEX VALUES MAY CLIMB TO OR JUST ABOVE 105 DEGREES  
ACROSS CENTRAL TEXAS. DESPITE THESE NUMBERS, A HEAT ADVISORY IS  
NOT EXPECTED GIVEN THAT 1) PEAK HEAT INDEX VALUES WERE JUST BELOW  
105 ON SUNDAY AFTERNOON AND 2) HEAT INDEX VALUES ON TUESDAY SHOULD  
BE LOWER AS DRIER AIR OVERSPREADS THE REGION. REGARDLESS,  
INDIVIDUALS ACROSS CENTRAL TEXAS SHOULD REMAIN VIGILANT AND  
CONTINUE TO EXERCISE THEIR HEAT SAFETY RULES. ELSEWHERE, A LIGHT  
NORTHWESTERLY BREEZE IS FORECAST BEHIND THE FRONT WHICH SHOULD  
RESULT IN CONTINUED WARMTH (DUE TO SLIGHT DOWNSLOPING), BUT  
SLIGHTLY MORE PLEASANT CONDITIONS DUE TO THE DRIER AIR. HIGH  
TEMPERATURES BEHIND THE FRONT WILL STILL MANAGE TO CLIMB INTO THE  
LOW TO MID 90S.  
 
BY THIS EVENING, THE FRONT SHOULD HAVE CLEARED MOST OF CENTRAL  
TEXAS WITH CLEARING SKIES. THE LOW MOISTURE CONTENT AND LIGHT  
WINDS OVERNIGHT SHOULD PROMOTE MODEST RADIATIONAL COOLING AND  
ALLOW TEMPERATURES TO FALL INTO THE 60S AND LOW 70S.  
 
BAIN  
 

 
   
LONG TERM
 
/ISSUED 406 AM CDT MON AUG 20 2018/  
/TUESDAY THROUGH SUNDAY/  
 
POSTFRONTAL DAYTIME TEMPERATURES HAVE BEEN 10 TO 20 DEGREES BELOW  
NORMAL ACROSS THE CENTRAL PLAINS, BUT THE MAIN THRUST OF COLD  
ADVECTION WILL CHASE THE DEPARTING UPPER LOW INTO THE EASTERN U.S.  
DEEP NORTHERLY FLOW WILL CONTINUE ACROSS NORTH AND CENTRAL TEXAS  
ON TUESDAY, BUT THE WEAK SURFACE WINDS WILL PROVIDE NEGLIGIBLE  
COLD ADVECTION. HOWEVER, DEW POINTS WILL FALL BY 10 DEGREES OR  
MORE. WITH ABUNDANT SUNSHINE, THE LIGHT WINDS AND THE REDUCTION IN  
HUMIDITY WILL ONLY HELP BUOY DAYTIME TEMPERATURES. HIGHS WILL BE  
NEAR NORMAL ALONG AND NORTH OF THE I-20 WHERE THE POSTFRONTAL  
ADVECTION WILL BE MAXIMIZED, BUT PORTIONS OF CENTRAL TEXAS MAY  
FLIRT WITH THE CENTURY MARK TUESDAY AFTERNOON. DESPITE THE WARM  
TEMPERATURES, THE LOWER HUMIDITY WILL TAKE THE EDGE OFF THE HEAT.  
IN ADDITION, EVENING TEMPERATURES WILL FALL MORE READILY, AND  
DAYBREAK TEMPERATURES TUESDAY THROUGH THURSDAY WILL BE QUITE  
PLEASANT FOR AUGUST.  
 
OUR FRONTAL BOUNDARY WILL BEGIN TO RETREAT/ERODE DURING THE MIDDLE  
OF THE WEEK, WITH THE ONSET OF RETURN FLOW ACROSS THE BIG COUNTRY  
AS EARLY AS WEDNESDAY. WHILE THIS MIGHT SUGGEST THE POTENTIAL FOR  
SOME WARM-FRONTAL ISENTROPIC LIFT, WITH INTENSIFYING RIDGING  
ALOFT, THIS SHOULD BE LIMITED TO A FEW CLOUDS. SOUTHERLY WINDS  
WILL ENSUE REGIONWIDE BY THURSDAY, WITH A STEADY INCREASE IN GULF  
MOISTURE THEREAFTER. THE HUMIDITY MAY SLOW THE WARMING TREND, BUT  
WITH RIDGING ANCHORED OVER THE LONE STAR STATE, TRIPLE DIGITS  
SHOULD PEPPER THE REGION LATE IN THE WEEK. EVEN WITH TROPICAL  
MOISTURE IN PLACE, THE INCREASING LENGTH OF NIGHT SHOULD ALLOW  
MOST AREAS TO FALL INTO THE MID 70S FOR MORNING LOWS (THOUGH  
INNER-URBAN AREAS IN THE DALLAS/FORT WORTH METROPLEX MAY SEE LOWS  
NEAR 80F). EXTENDED GUIDANCE IS HINTING THAT THE RIDGE MAY SHIFT  
TO THE EAST THIS WEEKEND, WHICH WOULD TAP THE BRAKES ON THE  
TEMPERATURES WHILE OPENING THE POSSIBILITY FOR COASTAL CONVECTION  
TO APPROACH FROM THE SOUTHEAST. FOR NOW, WILL MAINTAIN A DRY  
FORECAST FOR THE FINAL WEEKEND OF AUGUST.  
 
25  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
DALLAS-FT. WORTH 95 73 96 72 95 / 5 5 0 0 5  
WACO 100 73 99 73 98 / 20 5 5 5 5  
PARIS 91 67 92 67 90 / 5 5 0 0 5  
DENTON 94 67 95 70 93 / 5 5 0 0 5  
MCKINNEY 94 68 94 69 93 / 5 5 0 0 5  
DALLAS 96 74 96 72 95 / 5 5 0 0 5  
TERRELL 95 70 95 71 94 / 10 5 0 0 0  
CORSICANA 99 74 97 70 96 / 20 5 5 0 0  
TEMPLE 99 74 99 73 99 / 30 10 10 5 5  
MINERAL WELLS 94 68 96 70 95 / 5 5 0 5 5  
 

 
   
FWD WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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