175  
FXUS63 KEAX 122305  
AFDEAX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO  
605 PM CDT MON MAY 12 2025  
   
KEY MESSAGES  
 
- TEMPERATURES CONTINUE TO WARM  
 
- ISOLATED RAIN CHANCES THURSDAY NORTHERN MISSOURI  
 
- RAIN/STORM ACTIVITY SATURDAY INTO SUNDAY; PATTERN REMAINS UNCERTAIN  
 
 
   
DISCUSSION  
 
ISSUED AT 340 PM CDT MON MAY 12 2025  
 
AXIS OF DEEP H5 TROUGH IS MOVING INLAND IN THE WESTERN CONUS WHICH  
HAS PROVIDED INCREASED FLOW TO AT LEAST MOVE THE NORTHERN RIDGE AXIS  
WHICH HAD BEEN A PART OF THE REX BLOCK PATTERN OVER THE PAST FEW  
DAYS. THAT RIDGE AXIS HAS NOW MADE IT INTO THE NORTHERN GREAT LAKES  
REGION. THE MID-LEVEL CLOSED-LOW HAS SHIFTED NORTHWARD AS A  
SECONDARY MID-LEVEL RIDGE AXIS EXPANDS ACROSS SOUTHERN HIGH PLAINS.  
THIS MID-LEVEL LOW OVER THE GULF REGION THOUGH HAS MOVED A BIT  
FURTHER EASTWARD THAN WAS PROGGED IN MODEL GUIDANCE A COUPLE OF DAYS  
AGO. AS A RESULT, THE BETTER LIFT ASSOCIATED WITH THIS HAS ALSO  
SHIFTED EAST, KEEPING MOST OF THE LIGHT RAIN SHOWER ACTIVITY EAST OF  
HWY. 63. MID AND UPPER-LEVEL MOISTURE HAS WORKED AROUND THE LOW TO  
THE BACK SIDE, PLACING SOME CLOUD COVER IN OUR SOUTHEASTERN CWA.  
BOUNDARY LAYER DESTABILIZATION TODAY DID HELP GENERATE A FEW CUMULUS  
CLOUDS, BUT MOISTURE RETURN HAS STILL BEEN SLOW TO START ACROSS OUR  
AREA. WE DID ALSO SEE SOME MIXING THAT HAS CREATED WIND GUSTS  
BETWEEN 15-20 MPH THIS AFTERNOON. FOR THE REMAINDER OF THE EVENING,  
WEAK DCVA WILL CONTINUE EAST OF INTERSTATE 35, WITH STRONGEST LIFT  
REMAINING WELL EAST OF HWY. 63. WILL MAINTAIN SLIGHT CHANCE (15 TO  
20 PERCENT) FOR RAIN IN OUR EASTERN COUNTIES ALONG HWY. 63, BUT THE  
BETTER CHANCES WILL PUSH OFF INTO EASTERN MISSOURI. IF THE CLOUD  
COVER THIS AFTERNOON BREAKS APART OVERNIGHT AND ALLOWS FOR STRONGER  
RADIATIONAL COOLING, THERE MAY EVENTUALLY BE ENOUGH MOISTURE  
AVAILABLE IN OUR EASTERN AND SOUTHEASTERN COUNTIES WHERE PATCHY FOG  
COULD DEVELOP. HIGH RESOLUTION GUIDANCE HAS BEEN SPOTTY ON  
DEVELOPING THIS, BUT UNDER THE RIGHT CLEARING CONDITIONS COULD  
OCCUR.  
 
TUESDAY, WEST COAST TROUGH CONTINUES TO DIG AND PROPAGATE TOWARD THE  
INTERMOUNTAIN WEST WHILE AREA OF STRONGER DCVA PROMOTES LIFT AND  
SURFACE CYCLOGENESIS ACROSS THE FRONT RANGE. THIS CREATES A SOUTHERLY  
RESPONSE IN FLOW BELOW 850MB ACROSS MUCH OF THE PLAINS, INCREASING  
THE WAA AS FAR EAST AS THE LOWER MISSOURI RIVER VALLEY. WHILE THE  
STRONGER WAA AXIS REMAINS OVER CENTRAL KANSAS, THERE SHOULD BE  
ENOUGH TO ALLOW SUBTLE H5 HEIGHT RISES TO EXPAND INTO OUR WESTERN  
COUNTIES THROUGH THE DAY ON TUESDAY, KEEPING CONDITIONS FOR THE  
WESTERN HALF OUR OF AREA DRY. THE CLOSED MID-LEVEL LOW SLOWLY  
CONTINUES TO MOVE EASTWARD, BUT THERE IS SOME WEAK VORTICITY CAPABLE  
OF PROMOTING LIFT PRIMARILY ALONG HWY. 63 AND EASTWARD. SYNOPTIC  
SCALE MODELS AND ENSEMBLES HAVE MAINTAINED LOW-END PROBABILITIES FOR  
LIGHT RAIN SHOWER ACTIVITY TUESDAY AFTERNOON FOR OUR FAR EASTERN  
COUNTIES. HOWEVER, CAMS SINCE 12Z THIS MORNING HAVE BEEN DRY, AND  
BLENDED GUIDANCE SOLUTIONS AS A RESULT HAVE BEEN DECREASING RAIN  
CHANCES OVER THEIR PAST FEW RUNS. WITH THE MID-LEVEL LOW STILL IN  
PLACE AND PROMOTING WEAK LIFT, WILL CONTINUE SLIGHT CHANCE FOR RAIN  
SHOWERS ALONG HWY. 63 ON TUESDAY AFTERNOON. IF RAIN SHOWERS DO NOT  
DEVELOP, STILL EXPECTING CLOUD COVER TO INCREASE FOR AREAS EAST OF  
INTERSTATE 35, AND MAY BE ABLE TO EXPAND WESTWARD. IF THERE IS  
ENOUGH BREAKS IN THE CLOUD COVER OUR WESTERN AREAS INCLUDING THE KC  
METRO, EXPECTING TEMPERATURES IN THE MID 80S TUESDAY AFTERNOON,  
WHILE AREAS FROM CENTRAL MISSOURI EASTWARD SHOULD BE COOLER WITH  
HIGHS IN THE UPPER 70S. ALONG THE KANSAS-MISSOURI STATELINE,  
TEMPERATURE INNER-QUARTILE VALUES ARE GENERALLY BETWEEN 82F AND 86F,  
WHILE IN CENTRAL MISSOURI SPREAD IS GREATER DUE TO DIFFERENCES IN  
CLOUD COVER PROJECTIONS, THEN FURTHER EAST WHERE OVERCAST SKIES ARE  
HIGHLY CONFIDENT, TEMPERATURES ARE CLUSTERED AROUND 77F AND 79F.  
WEDNESDAY WESTERN TROUGH AXIS CROSSES THROUGH THE INTERMOUNTAIN WEST  
AND DEEPENS SURFACE CYCLONE ACROSS THE PLAINS. THIS SHOULD BE THE  
FINAL PUSH TO MOVE THE MID-LEVEL LOW WELL EAST OF THE MISSISSIPPI  
RIVER VALLEY. STRONGER WAA AXIS PUSHES INTO OUR AREA AND HELPS  
AMPLIFY AN H5 RIDGE AXIS. WHILE THETA-E ADVECTION MAY INCREASE, THE  
SUBSIDENCE ASSOCIATED WITH THE AVA REGIME WILL KEEP CONDITIONS DRY.  
CLEAR CONDITIONS IN OUR WESTERN COUNTIES SHOULD PROMOTE A DECENT  
AMOUNT OF MIXING, ACHIEVING TEMPERATURES IN THE UPPER 80S, AND  
POTENTIAL TO CROSS ABOVE 90F. EAST OF INTERSTATE 35 FOR WEDNESDAY,  
TEMPERATURES STAY IN THE MID TO UPPER 80S. THURSDAY, TROUGH CROSSES  
THROUGH THE ROCKIES, AND CLOSES OFF FURTHER NORTH WHILE A VORT MAX  
BEGINS TO LIFT NORTHEASTWARD ACROSS THE CENTRAL PLAINS. THIS IS  
CURRENTLY SET TO TRACK THE SURFACE CYCLONE WEST AND NORTHWEST OF OUR  
FORECAST AREA. WE MAY SEE SOME WEAK CONVERGENCE WITH SURFACE  
PRESSURE FALLS, BUT BETTER KINEMATICS STRETCH FROM CENTRAL KANSAS TO  
EASTERN NEBRASKA AND CENTRAL IOWA. WE MAY SEE SOME LIGHT ACTIVITY IN  
FAR NORTHERN MISSOURI. GEFS AND OTHER ENSEMBLE SUITES GENERALLY HOLD  
A LESS THAN 20 PERCENT CHANCE FOR MEASURABLE RAIN THOUGH, SO FAR NOW  
WILL KEEP SLIGHT CHANCE POPS RIGHT ALONG THE IOWA BORDER FOR  
WEDNESDAY.  
 
FRIDAY THROUGH THE REMAINDER OF THE WEEKEND, THE PATTERN EVOLUTION  
REMAINS UNCERTAIN. THIS APPEARS TO STILL BE TIED TO HOW QUICKLY THE  
TROUGH BEGINS TO LIFT, ALONG WITH SECONDARY SHORT-WAVE TROUGH THAT  
EJECTS OUT OF THE SOUTHERN PLAINS. THERE WILL LIKELY BE A DEEPER  
SURFACE CYCLONE EITHER IN THE NORTHERN PLAINS OR MIDWEST REGION,  
THAT COULD EXTEND SURFACE TROUGHING OR PUSH A COLD FRONT THROUGH THE  
AREA FRIDAY INTO SATURDAY. SOME ENSEMBLE MEMBERS DEVELOP A WEAK  
SURFACE CYCLONE ACROSS THE SOUTHERN PLAINS AND INTO THE OZARKS  
REGION THAT COULD ALSO BRING ACTIVE WEATHER. AT LEAST FOR NOW  
AMONGST DETERMINISTIC SOLUTIONS, THE BETTER INSTABILITY AND SUPPORT  
IS EITHER WELL NORTH OF THE AREA OR JUST SOUTHWARD ON FRIDAY THROUGH  
MOST OF SATURDAY. IT IS NOT UNTIL LATER SATURDAY INTO SUNDAY WHEN A  
STRONGER VORT MAXIMA EJECTS AND BETTER FORCING BRINGS MORE ACTIVITY  
TO THE AREA. 12Z ENSEMBLE RUNS THIS MORNING HAVE BEEN PAINTING  
HIGHER PROBABILITIES FOR RAINFALL LATE SATURDAY THROUGH MOST OF  
SUNDAY. IF WE SEE BETTER FORCING AND STRONG THETA-E ADVECTION, WE  
COULD SEE STRONGER TO SEVERE STORMS OVER THE WEEKEND. LOOKING BEYOND  
THE WEEKEND INTO NEXT WEEK, ENSEMBLE PROBABILITIES ARE FAVORING  
MULTIPLE WAVES MOVING ACROSS THE AREA WITH FAIRLY EFFICIENT QPF.  
THEREFORE, ANTICIPATING AN ACTIVE PATTERN FOR NEXT WEEK.  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z TUESDAY/  
 
ISSUED AT 603 PM CDT MON MAY 12 2025  
 
SUB IFR CONDITIONS ARE POSSIBLE OVERNIGHT TONIGHT AS LOW LYING  
FOG DEVELOPS OVERNIGHT. THIS FOG IS MOST LIKELY EAST OF HIGHWAY  
65, SO NO MENTION IN THE TERMINALS AT THIS TIME. FOG TO LIFT MID  
MORNING, WITH SCATTERED CUMULUS ~3-4K FEET AGL DEVELOPING  
THROUGHOUT THE DAY. SOUTHEAST WINDS PREVAIL THROUGH THE PERIOD.  
 
 
   
EAX WATCHES/WARNINGS/ADVISORIES  
 
MO...NONE.  
KS...NONE.  
 
 
 
 
 
DISCUSSION...KRULL  
AVIATION...BT  
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