383  
FXUS63 KIWX 271858  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
258 PM EDT WED OCT 27 2021  
   
SYNOPSIS
 
 
ISSUED AT 250 PM EDT WED OCT 27 2021  
 
INCREASING CLOUDS AND DRY CONDITIONS ARE EXPECTED INTO THURSDAY.  
THURSDAY AFTERNOON, RAIN COMES IN AND CONTINUES INTO EARLY  
SATURDAY. THE HEAVIEST OF THAT RAIN IS EXPECTED THURSDAY EVENING  
INTO FRIDAY MORNING. HIGHS STAY IN THE 50S TO AROUND 60 DEGREES INTO  
THE WEEKEND BEFORE A COOLING TREND COMMENCES EARLY NEXT WEEK.  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH THURSDAY)  
ISSUED AT 250 PM EDT WED OCT 27 2021  
 
BLOCKING HIGH PRESSURE AND MID LEVEL RIDGING IN SOUTHEAST CANADA  
CONTINUES TO CONTROL OUR WEATHER THIS AFTERNOON AND TONIGHT WITH DRY  
WEATHER. HOWEVER, LOW LEVEL MOISTURE ADVECTION ON LIGHT EAST WINDS  
PUSHES STRATUS CLOUD COVER BACK OVER THE AREA THIS AFTERNOON AND  
EVENING. THIS WILL SERVE AS A SET OF INSULATION AND NOT ALLOW  
RADIATIONAL COOLING, BUT WILL KEEP TEMPERATURES FROM FALLING FURTHER  
THAN THE MID TO UPPER 40S. SO, FROST IS NOT EXPECTED TO BE A PROBLEM  
TONIGHT.  
 
THOSE LOW LEVEL STRATUS CLOUDS STAY AROUND THE AREA ON THURSDAY,  
HOWEVER, THE MID LOW LEVELS OF THE ATMOSPHERE WON'T MOISTEN UP TO BE  
CONDUCIVE TO RAIN UNTIL MIDDAY, AT THE EARLIEST, AS THE LOW LEVEL  
JET PUSHES INTO THE AREA. DURING THE AFTERNOON POCKETS OF MID LEVEL  
OMEGA LINE UP WITH SOME LOW LEVEL MOISTURE CONVERGENCE AND UPPER  
LEVEL DIVERGENCE AND NOW WITH PWATS OVER 1", SOME LIGHT TO MODERATE  
RAIN IS EXPECTED TO MOVE IN DURING THIS TIME. BETWEEN THURSDAY  
AFTERNOON AND FRIDAY MORNING PERIODS OF RAIN MOVE THROUGH WITHIN THE  
AFOREMENTIONED FORCING AND MOISTURE, HOWEVER, THE FORCING CALMS DOWN  
AS THE UPPER LOW CENTER APPROACHES THE AREA. SOME MOISTURE STILL  
EXISTS IN THE COLUMN SO EXPECT TIMES OF LIGHTER RAIN DURING THE DAY  
FRIDAY. WITH QPF RANGING FROM JUST UNDER A HALF INCH IN THE  
NORTHWEST TO AROUND 1 INCH IN NW OH, WILL CONTINUE TO CARRY THE IDEA  
THAT THIS WON'T CREATE TOO MUCH MORE FLOODING ISSUES FOR THE AREA  
WITH SOME RIVERS ALREADY STARTING TO COME OUT OF FLOOD ALREADY.  
TEMPERATURES BOTH DAYS, THURSDAY AND FRIDAY RESIDE IN THE MID TO  
UPPER 50S WITH LOWER 60S ALSO POSSIBLE EAST OF I-69 ON THURSDAY.  
SOME WIND GUSTS UP TO BETWEEN 15 AND 20 MPH ARE ALSO POSSIBLE ON  
THURSDAY WITH THE LOW LEVEL JET MOVING THROUGH OVERHEAD.  
 

 
   
LONG TERM
 
(THURSDAY NIGHT THROUGH WEDNESDAY)  
ISSUED AT 250 PM EDT WED OCT 27 2021  
 
RAINFALL BEGINS TO DISSIPATE SATURDAY MORNING INTO THE AFTERNOON  
WITH CLOUDS LINGERING EAST OF I-69 BEYOND SATURDAY EVENING AS THE  
LOW PRESSURE CENTER PASSES BY TO THE SOUTHEAST OF THE FORECAST AREA.  
MID LEVEL RIDGING MOVES IN FOR SATURDAY NIGHT AND CONTINUES THROUGH  
MONDAY KEEPING THOSE DAYS DRY. THEREAFTER, A COOLING TREND STARTS  
SUNDAY AND CONTINUES INTO THE NEXT WORK WEEK AS A COLD FRONT PASSES  
THROUGH. MODELS HAVE BEEN CREATING SOME FUNKY BUSINESS WITH THAT  
FRONT AND DEVELOPING WAVES ALONG IT. WITH THE COLD AIR COMING IN,  
BLENDS OF MODELS ARE MIXING PRECIPITATION FROM ONE MODEL AND ITS  
SLOWER TIMING WITH THE COOLER AIR OF ANOTHER AND ITS FASTER TIMING  
SO DON'T HAVE A LOT OF CONFIDENCE IN ANY WINTRY WEATHER THE BLENDS  
ARE PUTTING INTO THE LONG RANGE THIS FAR OUT ESPECIALLY WHEN A DRY  
FRONTAL PASSAGE IS A POSSIBLE SOLUTION.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)  
ISSUED AT 148 PM EDT WED OCT 27 2021  
 
UPPER RIDGING OVER THE REGION THIS AFTN TRANSLATES EWD TONIGHT  
WITH THE UPPER LOW LIFTING OUT OF THE SOUTHERN PLAINS INTO THE MID  
MS VALLEY. THE ASSOCIATED SFC LOW WILL BE SITUATED JUST SOUTH OF  
SAINT LOUIS BY THE END OF THE FCST PD. A DRY AIRMASS TODAY WILL  
CHANGE AS LLVL CIGS ADVECT WEST INTO IN FROM OHIO BY THIS  
EVENING. THE MVFR DECK WILL IMPACT KFWA AROUND 21-22Z AND AFTER  
03Z AT KSBN. EASTERLY FLOW WILL INCREASE TO AROUND 10 KTS BY  
SUNRISE THU.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
MI...NONE.  
OH...NONE.  
LM...NONE.  

 
 

 
 
SYNOPSIS...ROLLER  
SHORT TERM...ROLLER  
LONG TERM...ROLLER  
AVIATION...FRAZIER  
 
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WWW.TWITTER.COM/NWSIWX  
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA  
 
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