833  
FXUS64 KMRX 080714  
AFDMRX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
314 AM EDT THU MAY 8 2025  
   
..NEW SHORT TERM, LONG TERM
 
 
   
SHORT TERM
 
 
(TODAY AND TONIGHT)  
ISSUED AT 313 AM EDT THU MAY 8 2025  
 
KEY MESSAGES:  
 
1. STORMS WILL MOVE THROUGH THE REGION LATE THIS AFTERNOON INTO THE  
EVENING HOURS.  
 
2. SOME STORMS WILL LIKELY BE STRONG TO SEVERE WITH LARGE HAIL AS  
THE GREATEST CONCERN, UP TO THE SIZE OF GOLF BALLS. LOCALIZED  
DAMAGING WINDS ARE ALSO POSSIBLE.  
 
DISCUSSION:  
 
CURRENTLY EARLY THIS MORNING, A WEAKENING CLOSED LOW IS CENTERED  
OVER MISSOURI WITH A FRONTAL BOUNDARY JUST SOUTH OF OUR REGION. A  
WEAK AREA OF LOW PRESSURE IS ALSO CENTERED JUST SOUTHEAST OF THE  
UPPER LOW. THROUGHOUT THE DAY, THE UPPER LOW WILL LIFT TOWARDS THE  
OHIO RIVER VALLEY WITH THE WEAK SURFACE LOW FOLLOWING A SIMILAR  
TREND. THIS WILL ALSO ALLOW PULL THE FRONTAL BOUNDARY NORTHWARD INTO  
OUR AREA AS A WARM FRONT. THE COMBINATION OF SURFACE HEATING AND  
HEIGHT FALLS WILL ENHANCE THE THERMODYNAMIC ENVIRONMENT. THIS IS  
ESPECIALLY TRUE WITH INDICATIONS OF MLCAPE TO 1,500 J/KG OR MORE AND  
MID-LEVEL LAPSE RATES AROUND 7 CELSIUS/KM. THE CAMS INDICATE  
DEVELOPMENT BEING GENERALLY TO OUR NORTHWEST DURING THE AFTERNOON  
WITH A PROGRESSION THROUGH OUR AREA AROUND 4 TO 9 PM. THIS TIMING  
WILL ALLOW FOR FURTHER DESTABILIZATION.  
 
WINDS WILL BE FAIRLY UNI-DIRECTIONAL THROUGH THE PROFILE AND WEAKER  
IN THE LOWER LEVELS, BUT EFFECTIVE SHEAR OF 30 KTS OR GREATER IS  
ALSO ANTICIPATED. THIS ENVIRONMENT WILL SUPPORT ORGANIZED CONVECTION  
WITH SOME SUPERCELLS ALSO POSSIBLE. ON TOP OF THE OVERALL LAPSE  
RATES AND INSTABILITY, WBZ HEIGHTS WILL BE BELOW 10,000 FEET AGL  
WITH INDICATIONS THAT 50 DBZ RETURNS AT JUST 25,000 FEET AGL BEING  
SUFFICIENT FOR 1 INCH HAIL. HAIL CAPE (-10 TO -30 CELSIUS REGION) IS  
ALSO INDICATED TO SURPASS 600 J/KG. THIS REALLY UNDERSCORES THE HAIL  
THREAT WITH GOLF BALL-SIZED REPORTS POSSIBLE. THE ORGANIZED NATURE  
OF STORMS WILL ALSO SUPPORT A DAMAGING WIND THREAT AS WELL. WITH HOW  
WEAK THE FLOW IS IN THE LOWER LEVELS, THE TORNADO THREAT IS LOW  
OVERALL UNLESS SOMETHING WERE TO SPIN UP ALONG THE BOUNDARY ITSELF.  
 
ACTIVITY IS EXPECTED TO DIMINISH ALONG SOUTHERN PORTIONS OF THE AREA  
LATER IN THE NIGHT AS THE FRONT DRIFTS BACK SOUTHWARD. MORNING FOG  
WILL BE POSSIBLE FOLLOWING THE RECENT RAINFALL.  
 

 
   
LONG TERM
 
 
(FRIDAY THROUGH WEDNESDAY)  
ISSUED AT 313 AM EDT THU MAY 8 2025  
 
KEY MESSAGES:  
 
1. FOR FRIDAY THROUGH SUNDAY, RAIN CHANCES WILL BE VERY LIMITED  
OUTSIDE OF THE SOUTHERN HALF OF THE AREA.  
 
2. BY NEXT WEEK, MORE WIDESPREAD RAINFALL IS LIKELY WITH STORMS  
POSSIBLE TUESDAY AND WEDNESDAY.  
 
FRIDAY THROUGH SUNDAY  
 
AT THE START OF THE PERIOD, A CLOSED LOW WILL BE CENTERED OVER THE  
EASTERN GREAT LAKES WITH ANOTHER CLOSED LOW DEVELOPING OVER  
ARKANSAS. THE FRONTAL BOUNDARY FROM THE SHORT TERM PERIOD WILL BE  
CENTERED JUST TO OUR SOUTH. THROUGHOUT THE DAY ON FRIDAY, THE CLOSED  
LOW TO OUR SOUTHWEST WILL STRENGTHEN WITH THE FRONTAL BOUNDARY  
DRIFTING FURTHER SOUTH AS HIGH PRESSURE EXPANDS FROM THE NORTH. THIS  
WILL KEEP TEMPERATURES FAIRLY MILD WITH RAIN CHANCES FOCUSED IN  
SOUTHERN PORTIONS OF THE AREA. BY SATURDAY, THE NORTHEASTERN CLOSED  
LOW WILL BE TRACKING INTO NEW ENGLAND WITH THE SOUTHWESTERN ONE  
DRIFTING TOWARDS THE NORTHWESTERN GULF. FURTHER EXPANSION OF HIGH  
PRESSURE WILL SHIFT RAIN CHANCES EVEN MORE SOUTHWARD WITH MUCH OF  
THE AREA LIKELY REMAINING DRY. BY SUNDAY, THE NORTHEASTERN CLOSED  
LOW WILL HAVE LIFTED AWAY FROM THE U.S. WITH THE ONE TO OUR  
SOUTHWEST EXPECTED TO DEEPEN. FOR SUNDAY ITSELF, CONTINUED HIGH  
PRESSURE WILL KEEP MUCH OF THE NORTHERN HALF OF THE AREA DRY.  
 
MONDAY THROUGH WEDNESDAY  
 
BY EARLY NEXT WEEK, THE CLOSED LOW IS CURRENTLY FORECAST TO TRACK  
NORTHWARD ALONG THE MISSISSIPPI RIVER VALLEY, WHICH WILL BRING A  
RETURN OF MORE WIDESPREAD RAINFALL TO THE AREA. BY TUESDAY, WAA FROM  
ITS PROGRESSION WILL LIKELY BRING INSTABILITY SUFFICIENT FOR  
SCATTERED CONVECTION. BY WEDNESDAY, THIS CLOSED LOW WILL LIFT TO THE  
NORTH WITH A DEEP TROUGH TO OUR NORTHWEST COMING INTO VIEW. THIS MAY  
PROVIDE EVEN BETTER SUPPORT FOR ORGANIZED CONVECTION ACROSS A LARGE  
AREA. CURRENTLY, ANALOGS ARE SHOWING AT LEAST LOW-END CHANCES FOR  
STRONG TO SEVERE STORMS TUESDAY AND/OR WEDNESDAY, SO IT WILL BE  
WORTH WATCHING.  
 

 
   
AVIATION
 
 
(06Z TAFS)  
ISSUED AT 103 AM EDT THU MAY 8 2025  
 
POOR AVIATION CONDITIONS ARE EXPECTED TO CONTINUE AT CHA WITH A  
REDUCTION TO IFR FORECAST IN THE NEAR FUTURE. AT TYS, HIGH MVFR TO  
LOW VFR IS EXPECTED, ALONG WITH SOME SHOWERS IN THE AREA JUST  
BEFORE SUNRISE. FOR TRI, FOG DEVELOPMENT IS FORECAST AGAIN IN THE  
HOURS AROUND SUNRISE BUT LIKELY WON'T BE THE PREVAILING  
CONDITION. THROUGHOUT MUCH OF THE DAY, VFR IS EXPECTED TO PREVAIL  
BEFORE STORMS DEVELOP BY LATE AFTERNOON. IT IS LIKELY THAT ALL OF  
THE SITES WILL SEE IMPACTS FROM THEM, BUT PROB30S WERE CARRIED  
BECAUSE OF TIMING DIFFERENCES. REDUCTIONS TO MVFR OR LOWER WILL BE  
LIKELY WITH ANY STORMS THAT DEVELOP AND PROGRESS OVER THE  
TERMINALS.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 81 59 77 55 / 50 50 40 20  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 78 57 74 51 / 50 50 30 10  
OAK RIDGE, TN 77 57 74 50 / 50 50 20 10  
TRI CITIES AIRPORT, TN 76 55 70 45 / 60 60 40 10  
 

 
   
MRX WATCHES/WARNINGS/ADVISORIES
 
 
NC...NONE.  
TN...NONE.  
VA...NONE.  

 
 

 
 
SHORT TERM...BW  
LONG TERM....BW  
AVIATION...BW  
 
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