418
FXUS63 KSGF 210831
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
331 AM CDT Tue May 21 2024

.KEY MESSAGES...

- Another warm day is in store for the region today ahead of a
  cold front then a return to more seasonably mild temperatures.

- Severe storms possible late this afternoon into the
  evening...with an Enhanced (3 of 5 level) risk over west
  central and central MO and a Slight Risk for much of the
  region southward to the Arkansas border. Damaging wind gusts
  are the primary concern followed by large hail up to two
  inches in size. The tornado threat is limited.

- Another round of severe weather is possible again Wednesday
  toward south-central Missouri with Slight (2 of 5 level) to
  Enhanced (3 of 5 level) risk. Damaging winds, large hail, an
  Isolated tornado and localized flooding will all be a
  concern.

- Unsettled weather may persist through the end of this week and
  into Memorial Day weekend (daily 30-50% chances for showers
  and thunderstorms).

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 235 AM CDT Tue May 21 2024

Another day of above average temperatures can be expected today
as strong warm air advection continues. Highs this afternoon
will again climb into the middle to upper 80s, which is a good
10 degrees above average for this time of year. Along with the
warm air, moisture will continue to feed into the region.

The primary concern for the forecast for today focuses on a
storm system in the plains and a cold front that will make its
way east through the day. In advance of the front, surface winds
will increase and become gusty (20-30mph) as the surface
pressure gradient tightens. The ingredients for severe weather
will be in place across the Ozarks as a result of the
aforementioned conditions. There will be a CAP (50-100 J/KG) in
place ahead of the front, though the cap will weaken with
afternoon heating. Convective is expected to develop late in the
afternoon as the front makes its way into the area. GEFS is
still showing mean SBCAPEs by 00z around 3500J/kg along the
Missouri/Kansas border and 0-6km bulk shear approaching 35-45
knots. Organized severe convection is expected with initial
storms developing as discrete supercells thanks to the ample
instability, however expectations are for the storms to become
linear quickly as the storms progress east along and ahead of
the cold front.

Models do indicate a dry layer initially around 700mb, but mid
level lapse rates will be strong (7-8 C/k). This would allow for
very large hail as a prime threat. If super cells develop a
limited tornado threat will exist, but storms should transition
into a line rather quickly which should limit this. As the
storms develop into a squall line, damaging winds will become a
concern with 60-70mph gusts likely.

The front, or effecting boundary, and line of storms will
progress through the Ozarks overnight, into Wednesday morning
with the severe threat continuing the overnight hours.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 235 AM CDT Tue May 21 2024

Wednesday into Thursday: Models, including synoptic and some of
the CAMS, push the front just south of the Ozarks Wednesday
morning, which should give the region a short reprieve.
However, the front/boundary is expected to move back north as
far as the I-44 corridor by Wednesday afternoon where the 850mb
front will have remained. With heating, the front and better
upper level support another round of severe weather is expected
Wednesday afternoon into the evening. Hail will once again be a
prime concern with two inch hail a possibility. Damaging winds
will also be a concern.

The southwest to northeast orientation of the front coincident
with the upper flow parallel with the stalling/slow movement of
the front will also potentially set the stage for training
storms and excessive rainfall into Thursday morning. Precipital
water values are forecast in the 1.5-1.75" range which is 1-2
standard deviations higher than normal for late May. The NBM
does indicate at least a 25% probability of 1-2 inches generally
along and south of I-44, with isolated chances for 3" of rain.
This rain, on top of earlier rains this week, would set the
stage for potential flooding.

The front will have made some progress south by Thursday
morning, but additional shortwave energy will move through the
southwesterly flow pattern and bring the chance for additional
severe weather. As another upper level trough moves across the
northern plains, a surface low develops in the plains and will
lift energy into the plains and the Ozarks. This combination
will allow for storms to develop again late Thursday afternoon
into the evening.

Friday into the Holiday Weekend - Southwest to westerly
upper flow will continue as shortwave energy shifts toward the
Canadian. Though weaker upper flow is forecast, several slow
moving frontal boundaries will move through the pattern serving
as the focus for convection each day. This will provide for
daily rain chances (20-50%), though not all areas will see rain
each day.

The pattern will see a shift finally by early next week,
becoming more northwesterly by Tuesday as an upper level low
moves south out of Canada and upper level ridging develops over
the Rockies. This would finally place the region under
northwesterly flow aloft or under the eastern edge of an upper
ridge. This process would allow for additional rain chances
Monday and Tuesday, but would finally bring drier weather to the
region for the middle to end of next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1239 AM CDT Tue May 21 2024

The region will see VFR conditions through this morning and
into the afternoon as a storm system develops in the plains.
Surface winds will be southerly and increase becoming gusty
into this afternoon.

A cold front will move through the region late this afternoon
into early this evening. Showers and thunderstorms will
occur as the front moves through the region. Some storms may be
severe, as storms move through the region, flight conditions
will be impacted with periodic MVFR to IFR conditions if storms
move over area airfield.

&&

.CLIMATE...
Issued at 100 PM CDT Wed May 15 2024

Record High Temperatures:

May 20:
KSGF: 90/1964
KJLN: 92/1956
KUNO: 89/1964

May 21:
KSGF: 91/1987
KJLN: 91/1987


Record High Minimum Temperatures:

May 20:
KSGF: 71/1902

May 21:
KSGF: 70/1902

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.

&&

$$

SHORT TERM...Hatch
LONG TERM...Hatch
AVIATION...Hatch
CLIMATE...Burchfield