529  
FXUS63 KIND 180812  
AFDIND  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE INDIANAPOLIS IN  
312 AM EST MON NOV 18 2024  
   
KEY MESSAGES
 
 
- SPRINKLES OR LIGHT RAIN POSSIBLE TODAY  
 
- MORE WIDESPREAD RAIN MONDAY NIGHT INTO TUESDAY  
 
- MUCH COLDER WEATHER WEDNESDAY NIGHT THROUGH SATURDAY WITH THE  
POTENTIAL FOR THE FIRST SNOWFLAKES OF THE YEAR WEDNESDAY NIGHT INTO  
THURSDAY  
 
- BREEZY WEDNESDAY AND THURSDAY AFTERNOON WITH GUSTS OF 25-35 MPH  
 

 
   
SHORT TERM (TODAY AND TONIGHT)
 
 
ISSUED AT 312 AM EST MON NOV 18 2024  
 
SUBTROPICAL MOISTURE PLUME IS PRESENT ACROSS THE AREA AND BROAD/WEAK  
ISENTROPIC ASCENT IS RESULTING IN SOME SPRINKLES OR LIGHT RAIN  
ACROSS PORTIONS OF THE AREA THIS MORNING. THIS COULD INCREASE SOME  
WITHIN A WEST-NORTHWEST TO EAST-SOUTHEAST ORIENTED BAND LATER THIS  
MORNING THROUGH THE AFTERNOON AS STRONGER CONVERGENCE AT THE LEADING  
EDGE OF LOW LEVEL JET CAUSES INCREASING ASCENT. AMOUNTS SHOULD BE  
LIGHT, GENERALLY A FEW HUNDREDTHS OF AN INCH FOR AREAS THAT DO  
RECEIVE RAIN.  
 
WARM ADVECTION IS STRONG ENOUGH FOR TEMPERATURES TO BE NEARLY 15  
DEGREES ABOVE MID-NOVEMBER CLIMATOLOGY (MID TO UPPER 60S). IT  
APPEARS PRECIPITATION WILL BE LIMITED IN COVERAGE AND INTENSITY  
ENOUGH NOT TO INTERFERE WITH THIS SIGNIFICANTLY, ESPECIALLY ACROSS  
SOUTHERN PORTIONS OF THE AREA WHERE PRECIPITATION WILL EXIT EARLIER.  
 
LARGE SCALE ASCENT FROM THE PLAINS LOW PASSING TO OUR NORTHWEST AND  
ANOMALOUS MOISTURE WITHIN ITS WARM CONVEYOR BELT WILL BRING A BAND  
OF SHOWERS TONIGHT. HREF PROBABILITY MATCH-MEAN PRECIPITATION  
AMOUNTS OF 0.10-0.25 INCHES ALIGNS WITH MULTI-MODEL MEAN. THE MAIN  
OUTLIER IS THE DETERMINISTIC ECMWF, EVEN AMONG ITS EPS MEMBERS.  
THERE IS SOME CONCERN THAT WHEN COMPARED TO PREVIOUS RAIN EVENTS,  
THIS ONE DISPLAYS A STRONGER WARM NOSE AND A SLIVER OF CAPE ABOVE  
THAT WHICH COULD SUPPORT CONVECTIVE ELEMENTS AND SOME ENHANCEMENT TO  
THE AFOREMENTIONED AMOUNTS. THIS TENDS TO GET WASHED OUT IN THE MEAN  
AND SHOULD BE LOCALIZED, BUT >0.50" AMOUNTS ARE POSSIBLE AT A FEW  
LOCATIONS.  
 
STRENGTHENING MSLP GRADIENT WILL CAUSE SOUTHEASTERLY WINDS TO  
STEADILY INCREASE THROUGHOUT THE DAY, PEAKING TONIGHT.  
 

 
   
LONG TERM (TUESDAY THROUGH SUNDAY)
 
 
ISSUED AT 312 AM EST MON NOV 18 2024  
 
THE LONG ADVERTISED DRAMATIC COOLDOWN FOR MID TO LATE WEEK CONTINUES  
TO BE THE PRIMARY FOCUS OF THE LONG TERM PERIOD, ALONG WITH  
POTENTIAL FOR THE FIRST SNOWFLAKES OF THE SEASON ASSOCIATED BOTH  
WITH A LARGE UPPER LOW EXPECTED TO PUSH ACROSS THE GREAT LAKES AND  
OHIO VALLEY REGION DURING THE PERIOD AND POSSIBLE LAKE ENHANCEMENT  
AS EARLY SEASON LAKE TEMPERATURES ARE RUNNING WELL ABOVE NORMAL.  
 
THE PRIMARY COLD FRONT WILL PUSH ACROSS THE AREA ON TUESDAY. THIS  
WILL BRING RAINFALL TO AN END ACROSS THE AREA BY MID TO LATE  
AFTERNOON TUESDAY AT THE LATEST, WITH A BREAK TUESDAY NIGHT AS A  
REINFORCING SHOT OF COLDER AIR FOLLOWS IN THE WAKE OF THE INITIAL  
FRONT.  
 
WHILE MODELS CONTINUE TO FOCUS STRONGER SURFACE CYCLOGENESIS TO OUR  
EAST WEDNESDAY INTO THURSDAY, SIGNIFICANT RUN TO RUN INCONSISTENCIES  
CONTINUE TO KEEP FORECAST CONFIDENCE LOW OVERALL IN SPECIFICS.  
 
NONETHELESS, PRECIPITATION CHANCES WILL RETURN WITH THE UPPER LOW  
AND POTENTIALLY THE BACKSIDE OF ANY SURFACE CYCLONE WEDNESDAY INTO  
THURSDAY/FRIDAY, WITH TEMPERATURES BECOMING COLD ENOUGH WEDNESDAY  
NIGHT INTO THURSDAY TO POTENTIALLY SUPPORT THE FIRST SNOWFLAKES OF  
THE SEASON. PROFILES MAY EVEN BECOME COLD ENOUGH TO SUPPORT BRIEF  
PERIODS OF ALL SNOW LATE WEDNESDAY NIGHT INTO EARLY THURSDAY, THOUGH  
VERY WARM GROUND OWING TO THE SIGNIFICANTLY ABOVE NORMAL  
TEMPERATURES EXPERIENCED MUCH OF THE LAST SEVERAL WEEKS AND IN THE  
FIRST FEW DAYS OF THIS WEEK SHOULD MITIGATE ANY REAL ACCUMULATION  
CHANCE OUTSIDE OF BRIEF BURSTS OF HIGHER RATES, PERHAPS AS A RESULT  
OF LAKE ENHANCEMENT.  
 
BROADLY SPEAKING, HOWEVER, THE MESSAGE REMAINS THE SAME - THE  
COLDEST CONDITIONS OF THE SEASON THUS FAR ARE EXPECTED LATE THIS  
WEEK, WITH DREARY AND BREEZY CONDITIONS (FREQUENT 25-35+ MPH GUSTS),  
AND FREQUENT CHANCES FOR SHOWERS, PERHAPS WITH SOME SNOWFLAKES,  
DURING THE LATTER HALF OF THE WORK WEEK. MOST IF NOT ALL OF THE SNOW  
APPEARS LIKELY TO MELT AS IT FALLS, BUT A LIGHT COATING DURING THE  
COOLEST TIMES AND IN THE MOST INTENSE SNOW SHOWERS CANNOT BE  
ENTIRELY RULED OUT.  
 
TEMPERATURES MAY MODERATE A BIT VERY LATE IN THE PERIOD INTO EARLY  
NEXT WEEK, THOUGH CONTINUED AND GROWING MODEL DIFFERENCES AT THAT  
TIME FRAME MAKE THIS VERY UNCERTAIN.  
 

 
   
AVIATION (06Z TAF ISSUANCE)
 
 
ISSUED AT 1235 AM EST MON NOV 18 2024  
 
IMPACTS:  
 
- MVFR CEILINGS POSSIBLE THIS MORNING  
 
DISCUSSION:  
 
MOIST LOW LEVELS MAY BE ENOUGH FOR AREAS OF MVFR STRATUS THIS  
MORNING, WITH A TENDENCY TO SHIFT NORTH THIS AFTERNOON. BRIEF LIGHT  
RAIN MAY OCCUR AT TIMES, BUT IS UNLIKELY TO BE HEAVY ENOUGH FOR  
REDUCED VISIBILITY. OTHERWISE, VFR CONDITIONS WILL PREVAIL. WINDS  
MAY BE CALM OR LIGHT/VARIABLE UNTIL MSLP GRADIENT TIGHTENS LATER  
THIS MORNING RESULTING IN SOUTHEASTERLY WINDS.  
 

 
   
IND WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...BRB  
LONG TERM...NIELD  
AVIATION...BRB  
 
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