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

Short term...(tonight)
issued at 237 PM CDT sun Aug 30 2015

Remnants of stalled frontal boundary still providing a focus for
shower development this afternoon in central Illinois. Plenty of
low level moisture in the boundary layer not mixing out entirely under
stratus and fog northwest of the boundary this morning, and other areas to
the south and east remaining partly cloudy through the afternoon.
Pooled moisture at the surface rich on both sides of the boundary and
temperatures tonight dropping with light winds and clearing skies. Fog
development expected for most of central Illinois tonight, mainly
after midnight.

Long term...(monday through sunday)
issued at 237 PM 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. Therefore...will maintain a dry forecast
through the week. The next significant chance for precipitation will
likely hold off until late in the weekend and early next week when a
short-wave trough gradually flattens the prevailing ridge and pushes
a cold front into the region. Models are in close 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 for now.

With ridging in place...high temperatures should climb into the
upper 80s and lower 90s each day. With dewpoints in the upper 60s
through the period...some humid conditions can be expected...though
heat index values should remain below 100.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 641 PM CDT sun Aug 30 2015

Fog formation later tonight is the main concern. The stalled out
frontal boundary across central Illinois has allow a pooling of moisture
in the vicinity of the front, where dewpoints climbed to the low
70s. Upper 60s dewpoints extend well north and south of the front
as well, so the potential for MVFR fog is high in a majority of
the area overnight. Hrrr/rap output are pointing toward the
potential of localized vlifr fog near pia and bmi. However, will
continue with only IFR fog later tonight in the tafs for now.

Winds will remain light and variable overnight, with a prevailing
S-SW wind developing after sunrise tomorrow. Wind speeds during
peak mixing tomorrow should remain less than 10kt.


Ilx watches/warnings/advisories...


Short term...hjs
long term...auten

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