Area Forecast Discussion

    
                        

656

FXUS63 KSGF 142306

AFDSGF



Area Forecast Discussion

National Weather Service Springfield MO

606 PM CDT Sat Jun 14 2025



.KEY MESSAGES...



- Shower and thunderstorm chances today will mainly be confined

  to southwestern portions of the forecast area (15-50%).



- On and off chances (15-50%) for showers and thunderstorms

  tonight, Sunday, and into Monday as a weak slow-moving system

  traverses the area. Isolated and localized instances of gusty

  winds and flooding are possible through Monday.



- Slight (15% Chance) Risk for severe thunderstorms Tuesday

  night across central Missouri, then again Wednesday for much

  of our forecast area.



- Humid conditions are expected all through next week. Signals

  point to temperatures nearing 90 F towards the end of the

  week. Therefore, we may see heat index values in the mid-90s

  to around 100 at times.



&&



.SHORT TERM /THROUGH SUNDAY NIGHT/...

Issued at 230 PM CDT Sat Jun 14 2025



Welcome to muggy-airmass-weak-flow-daily-MCS-to-MCV-induced-

shower/thunderstorm season! The bottom-line upfront for the next

few days is that an expansive muggy air mass is in place at the

surface, contributing at least modest instability across the

region. At the same time, the jet stream is noted well north of

the area, mainly across the US/Canada border. This is resulting

in very weak flow through the atmosphere. The combinations of

these mean that any thunderstorm complex that develops across

the Plains moves somewhat slowly and somewhat erratically,

making them difficult to pinpoint location, extent, and

longevity any given day. But the mug air mass in place will mean

at least isolated to scattered rain chances each day. This

forecast will have the latest details, but expect exact

locations, timings, and expected coverage of storms to change

with subsequent forecasts through the period given the pattern

will be rather static through next week.





15-50% chances for showers and thunderstorms today and tonight:



Radar and satellite imagery paired with RAP analysis depicts two

very weak MCV-type mid-level shortwaves. One within north-

central KS, and another around the corner of OK/KS/MO (i.e., our

southwestern CWA). Varying degrees of strengthening and

weakening of showers and thunderstorms have occurred within the

vicinity of this wave, with some light to moderate showers

having impacted the I-49 corridor down to McDonald County this

morning.



Negative vorticity and weaker instability within the upstream

side of a more distinct shortwave trough over the Mid-

Mississippi Valley is keeping much of the activity from pushing

further east into our area. Nevertheless, lingering weak

positive vorticity advection with the MCV along with surface

outflow from previous storms may force additional showers and

thunderstorms this afternoon into tonight, mainly in our

southwestern CWA (15-50% chance). While any storms would be

isolated to scattered, weak flow will mean they are relatively

slow-moving. Additionally, HREF mean has PWATs increasing above

1.5 inches this afternoon into tonight. Therefore, efficient

rain rates could produce some isolated nuisance flooding under

any stronger slow-moving storm.





On and off showers and thunderstorms Sunday into Monday:



CAMs are pretty consistent in an MCS developing across the

central Plains tonight. However, they are inconsistent in the

location of development and movement, which has impacts on our

thunderstorm chances Sunday into Monday. Some models show

development in OK while others show KS. Given southeastward

movement, development in KS would produce a more favorable path

into our area, while development in OK would create less of a

chance. Therefore, chances are still low in the 15-50% range for

early Sunday morning into the afternoon.



After the complex moves through Sunday morning, an MCV is

likely to develop somewhere within the MO/OK/AR region. The

placement of this will determine where the highest storm chances

are for Sunday afternoon into Monday. While there is a scenario

where much of our area stays mostly to completely dry, there is

consensus in at least some of the area seeing showers and

thunderstorms.



The MCV will be slow-moving. Similar to the pattern we just went

through, some more widespread stratiform rain is possible

Sunday morning, and again Monday night into Monday morning, with

more isolated to scattered showers and thunderstorms possible

during the afternoon and evening hours. Once again, any

thunderstorm could be slow-moving and have efficient rain rates

as PWATs approach 1.8-2.0". HREF LPMMs show many very localized

"blobs" of 1.5-2.5+ inches of rain beneath these stronger cells,

so very localized nuisance flooding is possible. Additionally,

the gusty sub-severe winds are also possible with the stronger

storms. There is a Marginal (1 of 5) Risk for severe

thunderstorms for our southwest counties, but this is for more

organized severe weather from decaying MCSs each night rather

than the afternoon thunderstorms.





During this whole period, highs in the middle 80s and lows in

the upper 60s are expected, with muggy "feels-like" air.



&&



.LONG TERM /MONDAY THROUGH SATURDAY/...

Issued at 230 PM CDT Sat Jun 14 2025



Slight (15% Chance) Risk for severe thunderstorms Tuesday night:



A slight pattern change is then in store Tuesday and Wednesday

as a modest trough is progged to extend into the central Plains

as it traverses from west to east. There are still some global

ensemble uncertainties in the shape and timing of the trough

given the weak nature of it, but some form of trough and

attendant surface cold front will move through during the

Tuesday through Wednesday period. The introduction of the trough

will increase deep-layer shear overtop of our muggy air mass in

place. As such, severe thunderstorms are possible along the

surface cold front. Tuesday, this would be over the northern

Plains, in which the remnants of may reach into our northern

counties late Tuesday night, making an MCS with damaging winds

and large hail the main risk.





Slight (15% Chance) Risk for severe thunderstorms Wednesday:



The better severe risk for our area comes Wednesday into

Wednesday night as the cold front is forecast to move through

the area. There are still some uncertainties in the exact type

of storm mode since global ensemble hodographs show just modest

deep layer shear (30-35 kts) which would be very borderline for

supercells. This would still be sufficient for damaging winds

and large hail. However, given a >25+ kt LLJ expected, if

supercells were possible, tornadoes would be an added risk.





Muggy air mass all through next week, 90-100F Heat Index values:



NBM dewpoints are forecast to be quite high through next week,

with the mean at mid-70s dewpoints as far out as Friday and

Saturday. This makes sense as both NAEFS and ECMWF ESATs show

>97.5th percentile mean specific humidity everyday through June

24th (with some days at the Max for the 30-year climatology for

mid-June). Additionally, behind the exiting trough, ensembles

are in agreement with a deep ridge building into the area, which

should allow highs to reach the upper 80s and lower 90s,

especially toward the weekend. Lows toward the weekend are also

forecast to reach the lower to middle 70s. Therefore, a heat

risk will begin to increase. Mean NBM heat index values reach

the middle 90s to lower 100s after Thursday. We will have to

monitor trends for any potential increases in this forecast.



&&



.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...

Issued at 606 PM CDT Sat Jun 14 2025



A few isolated showers and maybe a thunderstorm will be possible

this evening. Confidence in a TAF site being affect is low in

both convection development at all and if convection can

develop coverage will be limited.



Additional showers and thunderstorms are expected to develop

across the central Plains this evening into tonight. This

activity will have the potential of moving southeast into and

across the area tonight into Sunday morning. There are still

questions and exactly where this convection tracks. Depending

on the morning convection, it`s possible additional isolated to

scattered showers and thunderstorms will be possible Sunday

afternoon and evening.



There will also be the potential for some fog development

early Sunday morning if clouds can clear, but with the potential

for convection and clouds, this may help to limit the overall

fog potential some.



MVFR ceilings will be possible Sunday morning but could improve

during the afternoon hours, if the morning convection lingers

longer into the day it`s possible MVFR conditions also occur

into the afternoon hours.



&&



.SGF WATCHES/WARNINGS/ADVISORIES...

KS...None.

MO...None.



&&



$$



SHORT TERM...Price

LONG TERM...Price

AVIATION...Wise