Area Forecast Discussion

    
                        

816

FXUS63 KSGF 222030

AFDSGF



Area Forecast Discussion

National Weather Service Springfield MO

230 PM CST Sun Dec 22 2024



.KEY MESSAGES...



- Unsettled weather ahead this week. The highest rain chances

  occur Monday night through Tuesday night (60-90%) with the

  highest amounts along and south of the I-44 corridor. No

  severe thunderstorms or flooding expected.



- Additional rain chances (30-60%) by Thursday into Friday. Low

  potential for a few thunderstorms and some nuisance flooding.



- High confidence in above normal temperatures this week. Highs

  through mid-week in the upper 40s to middle 50s. By late

  week, highs reach into the upper 50s to near 60.



&&



.SHORT TERM /THROUGH TONIGHT/...

Issued at 230 PM CST Sun Dec 22 2024



Through Tonight: Surface high pressure has shifted east of the

region today, allowing mid-level height rises to build into

portions of the area. This is a result of a broad ridge across

the Rockies. Highs have varied from middle 40s (east) to lower

50s (west). Meanwhile, gusty southerly winds (around 20 to 25

mpg) continue to advect in a warmer airmass, and eventually

moisture as we progress into the overnight period. As this

happens, expect cloud cover to increase in coverage through

tonight as the ridge becomes suppressed to the west, allowing a

shortwave trough to translate out of the Plains on Monday.

Overnight lows fall into the 30s to near 40 out west.



&&



.LONG TERM /MONDAY THROUGH SATURDAY/...

Issued at 230 PM CST Sun Dec 22 2024



Monday-Wednesday: By Monday, a shortwave trough and associated

surface low bring increasing rain chances through the later half

of Monday. Moisture will be on the increase ahead of this

system, with surface dewpoints generally pushing into the 40s.

Highs top out in the upper 40s to lower 50s areawide. As omega

increases ahead of the approaching wave on Monday afternoon,

scattered light showers will develop across portions of southern

Missouri. Coverage is expected to remain scattered in nature

through the the evening. The highest rain chances (30-50%)

remain focused along and south of Interstate 44 through Monday

evening, ahead of the stronger forcing Monday night into

Tuesday. This increase in forcing will support higher (60-90%)

and more widespread rain chances. Ensemble guidance is in good

agreement on the heaviest rainfall occurring into southern

Missouri along the MO/AR border and south. In this area,

probabilities are 50-70% for exceeding 1 inch of rainfall from

Monday afternoon through Wednesday morning. Probabilities

rapidly decrease north of the Interstate 44 corridor. With this

in mind, we will continue to advertise 0.75 to 1.25 inches of

rainfall along and south of Interstate 44, with amounts tapering

off to 0.25 to 0.50 inch north of the interstate. Flooding is

not a concern with this round of rain, given the lack of any

convective elements (< 10% chance of thunderstorms in Southern

Missouri) and a more prolonged period of rainfall (24-36 hours).

However, it`s important to note that any rainfall received

earlier this week may saturate the soils ahead of additional

chances later this week. Lastly, no severe weather is expected

with this system given the lack of any instability. Rain chances

gradually diminish from west to east from overnight Tuesday

into Wednesday morning.



A mostly dry and cloudy day is in the forecast behind this

system on Wednesday (Christmas Day), with rain chances

diminishing early. Highs on Wednesday reach into the upper 40s

to lower/middle 50s.



Thursday-Saturday: As quick as one system exits, yet another

system takes shape with an upper-level wave coming off the

Rockies. Ensemble guidance is coming into better agreement over

the last 24 hours on the timing and location of this trough as

it builds into the region. The most likely scenario at this time

supports increasing rain chances on Thursday morning and through

the remainder of the day. Rain chances are highest (30-60%)

Thursday afternoon through Thursday night. Additionally, a look

at 500mb charts highlight at a neutral to negatively tilted

trough/closed upper- level low as the next system builds out of

the Central Plains. Moisture return appears to be a bit better

ahead of this late week system, with perhaps some marginal

amounts of instability sneaking into Southern Missouri. This

would introduce the chance for a few thunderstorms, though the

severe potential appears to remain suppressed south of the area

at this time given the lack of sufficient instability nosing

into the area. This is highlighted by the CIPS Severe

Probability Guidance and CSU Machine-Learning Severe

Probabilities. It will be worth monitoring through the coming

days, as a low confidence scenario exists for a few strong to

severe thunderstorms if instability materializes. Additionally,

more rainfall on top of saturated soils and dormant vegetation

may introduce a low threat for some minor flooding, especially

across portions of southern Missouri. NBM guidance depicts a

40-60% chance for greater than 1 inch of rainfall in this area

with the next event. There still remains some smaller

differences amongst the suite of ensembles, with confidence

increasing as we progress through the week.



In addition to rain chances lingering through late week, above

normal temperatures will remain a headline. 850mb temperatures

reach towards 8 to 10 C by Thursday and Friday. This will

support warmer surface temperatures, despite overcast skies and

rain chances in the area. Highs are forecast to be in the

middle to upper 50s, with a few locations likely to exceed 60.

NBM depicts 40-60% chances for exceeding 60 degrees across

southern Missouri on Thursday and Friday. The above normal

temperatures (5-10 degrees) persists through next weekend, with

low rain chances (10-20%).



&&



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

Issued at 1045 AM CST Sun Dec 22 2024



Clouds begin to increase in coverage this evening into the

overnight ahead of a stretch of unsettled weather this week.

Ceilings generally remain VFR through Monday morning, before

lower MVFR ceilings around 3000 feet are introduced late in the

TAF period. Winds out of the south-southeast through the period,

with wind gusts at KJLN and KSGF around 20 to 25 knots.

Additionally, LLWS around 35 to 40 knots out of southwest has

been introduced for the overnight period. A few isolated showers

may occur late in the TAF period, but coverage remains more

sparse until late Monday afternoon into the evening.



&&



.SGF WATCHES/WARNINGS/ADVISORIES...

KS...None.

MO...None.



&&



$$



SHORT TERM...Perez

LONG TERM...Perez

AVIATION...Perez