Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 250834

Area Forecast Discussion
National Weather Service Lincoln IL
334 AM CDT MON APR 25 2016

.SHORT TERM...(Today)
ISSUED AT 333 AM CDT Mon Apr 25 2016

Storm system over eastern South Dakota as of 300 am is expected to
track east along a stalled frontal boundary over northern Iowa east
through southern Wisconsin later today. A cold front located from
the low over eastern South Dakota southward through eastern Nebraska
will track slowly east today and not get into our area until first
thing Tuesday morning. Surface dew points in the mid to upper 50s
were noted just east of the cold front and as the boundary shifts
east today, so will the moist axis into our area this afternoon.

As was advertised with most model data, the storms that occurred
last night in Iowa have dissipated with the latest surface analysis
indicating a weak boundary/remnant outflow boundary over east
central Iowa. Most of the high res reflectivity simulations off the
4km NAM along with the WRF-ARW and NMM indicate redevelopment in
west-central Illinois later this afternoon. Surface temperatures in
the lower 80s combined with dew points in the upper 50s will yield
ML capes of around 1800 in a few areas along and west of the
Illinois River later this afternoon. That combined with rather steep
mid level lapse rates and 0-6km shear values of around 40 kts will
bring the threat for scattered thunderstorms after 300 pm, some of
which may produce strong winds and large hail, roughly along and
west of a Springfield to Bloomington line.


.LONG TERM...(Tonight through Sunday)
ISSUED AT 333 AM CDT Mon Apr 25 2016

After another warm day, with showers and thunderstorms chances
through the afternoon and into the evening hours, a series of
weather systems will bring precip for most of this week. The first
wave has slowed on approach overall, delaying the onset of precip.
Also, models are having some consistency issues with the extent of
the southerly progression of the front before the next wave moves
into the Midwest and enhances the precip/storms for Tuesday night
and into Wednesday.  Much of ILX sits in an area with limited severe
weather potential partially due to timing of the system late Tuesday
in the overnight hours. At any rate, the deep low over the southern
Plains ejects out and into the region, spreading best chances for
precipitation Wednesday and Wednesday night. Models still limiting
the progression of the warm front, keeping temperatures not quite as
warm for Tue/Wed ahead of the advancing storm center. By late
Thursday, the winds become more northerly and drier air slowly tries
to build back in for a brief break Thu night through later Friday.
The break looks to be short lived again as another wave moves out of
the long wave trof over the SW and into the region, bringing precip
back for next weekend. Overall, an active pattern, with more wet
than dry.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1156 PM CDT Sun Apr 24 2016

VFR conditions will prevail next 24hrs at all TAF sites. High
cirrus is all that is there now and will continue remainder of the
night. Convection in IA/MO will continue to move east but diminish
as it moves toward IL early in the morning. This will bring
scattered clouds at around 5-6kft tomorrow with some broken mid
clouds as well. Remnant outflow boundary will slow and sit over
western portions of the area tomorrow and think that additional
thunderstorms will develop along this boundary tomorrow afternoon
and then continue into the evening. Due to uncertainty of
location, will have VCTS at PIA/BMI which is closer to the mesolow
in the north. SPI/DEC/CMI will have VCSH...all after
00z...evening time frame. Winds will increase out of the south-
southwest tomorrow with gust to around 25-27kts. Gusts will
diminish tomorrow evening.


.ILX Watches/Warnings/Advisories...


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