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fxus63 kilx 171725 

Area forecast discussion
National Weather Service Lincoln Illinois
1225 PM CDT Mon Jun 17 2019

issued at 1003 am CDT Mon Jun 17 2019

Low clouds are hanging on much longer than expected this morning
and have nudged down afternoon highs a bit accordingly, mainly
north of I-70 where a modest surface boundary is analyzed. No big
changes in thinking for the convective chances later today.
Already seeing a couple areas of developing showers and
thunderstorms along portions of the Mississippi River this morning
which should begin to spread into the local forecast area late
morning and early afternoon. Highest chances for precip remain
along and south of I-72 today associated with lead shortwave
ejecting northeast towards St Louis and a low level convergence
band on the north periphery of the upper low. The threat for
flooding still appears greatest along the I-70 corridor in the
vicinity of the surface front.


Short term...(today and tonight)
issued at 329 am CDT Mon Jun 17 2019

A trough of low pressure is situated across the Southern Plains
early this morning. With the upper level low across central
Oklahoma, and the sfc low in southwest Missouri, moisture will
continue to be lifted up the Mississippi River valley into the
Midwest today.

A stalled out boundary remains across southern Illinois early this
morning. This will hold temperatures in the 60s, with elevated dew
points ranging from near 60 in Galesburg to the upper 60s in
southeast Illinois...closer to the frontal boundary. As today
progresses, the low core associated with this boundary will slide
east-northeast through southern Illinois into southern Indiana. This movement
will develop more showers and thunderstorms across the southern
half of the state during the late morning through the overnight.

Heavy rainfall will be possible as cams indicate a developing band
of activity this afternoon, along and south of the I-70
corridor...with upwards of 1 inch possible. This, in combination
with the already saturated soils, will provide the opportunity for
flash flooding to develop during the afternoon and evening.
Therefore, in collaboration with surrounding offices, a Flash Flood Watch
has been issued beginning at 12z today through 12z Tuesday.

Long term...(tuesday through sunday)
issued at 329 am CDT Mon Jun 17 2019

A break in rainfall will arrive Tuesday, however this will be
short lived as another weak of active weather shifts into the
central United States.

500mb heights will remain flattened across the US through mid-
week. This will continue to bring waves of precipitation to the
region this week. Although no significant severe weather is
expected through mid-week, heavy rainfall will bring the chance
for flooding and super saturated grounds. The wet pattern ends
Wednesday night, bringing drier conditions to the region during
the second half of the work week. Once again, this will not last
long, as another wave slides through Friday afternoon. Next
weekend is up in the air, as to if Saturday will be dry before
more rain Sunday, or if it will rain both Saturday and Sunday.
Models are not in good agreement as to what is expected.

Close monitoring of rainfall totals throughout the week will
continue over the next few days. Currently, forecasts around the
region are calling for the possibility of 3-4 inches across
central Illinois, while southern Illinois could see 5-6 inches
total. These are preliminary values, so these numbers have
numerous factors that will have to occur in order to pan out.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1223 PM CDT Mon Jun 17 2019

Low ceilings have persisted much longer than expected this
morning, but have seen a very gradual improvement through the mid
and late morning hours in terms of rising through IFR and some
locations have finally lifted back to MVFR. This trend should
continue with bmi holding onto IFR longest through the early
afternoon. Do still expect the clouds will lift to VFR mid to
late this afternoon, then low ceilings are expected to return late
this evening or overnight, including eventually bottoming out at
IFR late tonight into Tuesday morning. Light northeast winds will
prevail through the period. Scattered showers and thunderstorms
are possible near the southern terminals today, but the best
chances will be south of I-72, so for now will maintain dry


Ilx watches/warnings/advisories...
Flash Flood Watch through Tuesday morning for ilz062-063-066>068-



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