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Area forecast discussion 
National Weather Service Lincoln Illinois
1231 PM CDT Tue Mar 31 2015

issued at 1044 am CDT Tuesday Mar 31 2015

Surface trough has dropped into the far southeast kilx County Warning Area this morning,
resulting in a shift to northwesterly winds across the area.
Despite weak cold air advection behind this boundary, full late March sunshine
working on a dry airmass has resulted in 15z/10am temps rising
well into the 50s and even the lower 60s in a few spots. Forecast
soundings suggest afternoon highs will reach the middle to upper
60s, with readings near 70 possible across the S/SW. Bumped highs
up by a degree or two accordingly.


Short term...(today)
issued at 320 am CDT Tuesday Mar 31 2015

A weak dry cold front will pass from northwest to southeast across
central Illinois early this morning, with breezy southwest winds shifting
to northwest. With weak forcing for ascent and a lack of moisture in
the region, the front will come through dry with very few clouds.
Little cold air is resident behind the front with a large scale
ridge and warm air mass building into the northern plains and
Midwest. As a result, highs today will reach close to what occurred
Monday, with highs in the mid to upper 60s. Winds will gradually
decrease through the late afternoon as a surface high pressure
region shifts into the Midwest bringing weaker pressure gradients to
the area.


Long term...(tonight through monday)
issued at 320 am CDT Tuesday Mar 31 2015

Warming trend continues tomorrow with high temps in the low to mid
70s expected as 850mb temps climb to 9-10c with southerly flow ahead
of the approaching boundary. Clouds moving in ahead of the boundary
starting to show up in layer relative humidity in the NAM. The GFS is slowing a
bit with the advancement of the front, more in line with the
NAM/ECMWF...but still holding on to some prefrontal showers. Not
committing the forecast to precip before 12z on Thursday so far,
however. Southerly flow ahead of the actual front should allow for
warmer temps on Thursday, though cooler than the day before. By
Friday, however, the colder air mass has arrived and high temps drop
back into the 50s. As for the precipitation, with the later arrival
of the boundary, thunder will be possible through the daytime hours
on Thursday. Forecast soundings have CAPES from 1300-1700 j/kg by
18z. Storm Prediction Center has split the County Warning Area btwn a general thunder to the northwest...and a
marginal threat in the south and east.
Boundary lays out just to the southeast and lingers long enough for
another wave to run up and along the boundary on Friday, extending
the precip through Friday during the day, though the northern extent
will eventually be limited by where the stalled boundary finally
sets up. Forecast through the weekend dry, with highs in the
mid/upper 50s and lower 60s for Sat and sun, respectively. Next
precip chances return with the work week.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1231 PM CDT Tuesday Mar 31 2015

VFR conditions will prevail through the entire 18z taf period as
high pressure remains in control of the weather. Northwesterly
winds gusting to between 12 and 18kt will gradually subside by
sunset, followed by light/variable winds tonight. Once the high
shifts off to the east, a S/southeast return flow of around 10kt will
develop Wednesday morning. Even stronger/gustier winds are
anticipated after 18z as the pressure gradient tightens across the


Ilx watches/warnings/advisories...


short term...Onton
long term...hjs

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