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Area forecast discussion 
National Weather Service Lincoln Illinois
1232 PM CDT sun Aug 30 2015

issued at 1050 am CDT sun Aug 30 2015
fog finally starting to lift and break up northwest of the stalled
frontal boundary draped across central Illinois this morning.
Southerly winds south of the boundary will result in some drift
northward..with plenty of low level moisture in place to fill in the
sky with a broken cumulus field shortly after any clearing takes place
this afternoon. Same cumulus could develop some vertical extent and
turn into scattered showers and thunderstorms, particularly south and
east of the boundary. No updates anticipated at this time, just
minor adjustments to hourly temperature trends under the stratus/remaining
fog in the northwest.


Short term...(today)
issued at 324 am CDT sun Aug 30 2015

08z/3am surface analysis shows a stationary frontal boundary
extending from just south of Chicago to near Kirksville, Missouri.
While current kilx radar imagery indicates dry conditions across the
board...a few showers are noted further southwest from the Ozarks
into the Ohio River valley. Meanwhile...light/variable winds and
increased low-level moisture near the boundary have led to the
development of fog mainly along/northwest of a Pittsfield to
Bloomington-normal line. Hrrr continues to focus much of the
widespread fog across this area through will need
to monitor visby trends for a possible dense fog advisory. Further
east and south across the remainder of the County Warning Area...will only mention
patchy fog early this morning. After the morning fog
dissipates...widely scattered showers/thunder will develop ahead of
the decaying frontal boundary...primarily east of the Illinois
River. Afternoon high temperatures will be similar to
yesterday...perhaps a degree or two warmer in the middle 80s.

Long term...(tonight through saturday)
issued at 324 am CDT sun Aug 30 2015

The extended looks warm and dry as upper-level ridging dominates the
eastern Continental U.S. Through the end of the week. A slight weakness in the
ridge appears to develop across Illinois into the Ohio River
valley...potentially triggering isolated afternoon/evening
convection Tuesday through Friday. However...mid-level warming
beneath the ridge will likely lead to capping and an overall
suppression of convection. As a result...will maintain a dry
forecast with high temperatures climbing into the upper 80s and
lower 90s each day. The next significant chance for precipitation
will likely hold off until early next week when a short-wave trough
gradually flattens the prevailing ridge and pushes a cold front into
the region. Models are not in agreement concerning timing this far
out...but typical trend in this type of scenario is usually slower.
As a result...will maintain dry weather through Sunday.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1227 PM CDT sun Aug 30 2015

Pia improving slowly as the fog from this morning continues to
lift out and burn off. Bmi finally coming up to MVFR. Tempos for
MVFR at least for a couple hours northwest of the boundary, VFR through
the evening/Post sunset. Around midnight, expect the redevelopment
of the fog. Have started that trend without dropping the visible too
much. Areas may see IFR towards dawn. Light and variable
winds...with a southerly fetch more likely south of the decaying


Ilx watches/warnings/advisories...


short term...Barnes
long term...Barnes

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