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fxus63 kilx 232329 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
629 PM CDT Sat Mar 23 2019

Short term...(this evening through Sunday night)
issued at 250 PM CDT Sat Mar 23 2019

Water vapor satellite imagery clearly shows the center of our
upcoming storm system, located over the northwest tip of Kansas
early this afternoon. Radar echoes along the Illinois/Missouri
border are altocumulus clouds around 11,000 feet, but the main
area of rain was advancing across southwest Missouri. Lower levels
of the atmosphere over our area remain quite dry until at least
mid evening, so the main push of rain into our area should hold
off until after 8-9 PM. Areas near and east of I-57 are likely to
be dry until after midnight.

By midday Sunday, the low should be centered just north of Kansas
City, moving into south central Illinois during the evening. Both
the NAM and GFS show a nice push of cape ahead of this system, up
to around 500 j/kg SBCAPE as far north as Springfield. Latest Storm Prediction Center
day2 outlook nudges the marginal severe risk up against US just
south of Springfield, though the shear this far north will be a
little more borderline. Still, enough to keep thunder mention over
most of the area, though the storms will be a bit more elevated
across the northern County Warning Area. Thunder chances will quickly diminish
from northwest to southeast Sunday evening, as the low moves
deeper into southern Illinois, though the showers will linger well
past midnight.

Long term...(monday through saturday)
issued at 250 PM CDT Sat Mar 23 2019

The first half of the week looks fairly quiet, with an expansive
high pressure over the Great Lakes. Upper level ridging will build
along The Rockies and move east, resulting in a substantial
warming trend toward mid week. With a broad trough off the East
Coast during the second part of the week, the ridge will begin to
slow down. This results in some rather significant variations in
the longer range models. The European model, and the Canadian to a
lesser extent, form a rather strong closed low over the Central
Plains on Friday, which takes much of the weekend to fully exit
the Midwest. The GFS has the Midwest in more of a split flow,
resulting in a more clean and progressive frontal passage on
Friday. Will favor the slower solution for the moment, with high
rain chances for Friday.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 628 PM CDT Sat Mar 23 2019

Main forecast concerns will be ceilings lowering to MVFR tomorrow
morning, and the possibility of thunderstorms Sunday afternoon.
Trends on radar, satellite and observations show a delay in
precipitation onset until toward 06z.

Ahead of the rain, mid and high clouds will continue to stream
into central IL, with ceilings steadily lowering toward 8,000
feet. Clouds will continue to lower overnight as the lower levels
moisten up, but the main threat of rain development will be from
about kpia- kspi westward from 06-09z and around kcmi toward 12z.
Ceilings should reach MVFR territory toward 13z near kpia/kspi
and overspread the rest of the central Illinois taf sites by 15z,
eventually falling below 2,000 feet in most areas.

Instability parameters point toward thunder chances increasing
around 20z and continuing through the end of this taf period at
00z.

&&

Ilx watches/warnings/advisories...
none.
&&

$$

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