Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 261730

Area Forecast Discussion
National Weather Service Lincoln IL
1230 PM CDT Sun Mar 26 2017

Issued at 1010 AM CDT Sun Mar 26 2017

Nearly vertically stacked low centered just northwest of
Galesburg late this morning, with showers continuing to pinwheel
around it. An increase in showers is occurring over the western
CWA at the moment around the south side of the low, but these will
diminish early this afternoon as the low lifts into far northern
Illinois. Some minor adjustments made to the PoP trends over the
next few hours, but the going forecast was in fairly good shape.


.SHORT TERM...(Today and tonight)
ISSUED AT 339 AM CDT Sun Mar 26 2017

The upper level system effecting the CWA early this morning will
slowly move north-northeast, reaching the WI border late this
afternoon, around 21z. Scattered areas of light rain will continue
across the area and should come to an end by this evening. Dry
weather is then expected tonight, however, it will be brief as
another weather system will move into the area and bring showers to
the area after 09z tonight. Could be some thunder mixed in with the
showers, but appears parameters best support thunder on Monday. So
will leave out thunder for tonight.

With all the clouds and light precip expected today, temps will
increase only slightly, but be in the 60-65 degree range. Overnight
lows will be influenced by the same cloud cover, but with the
weather system pulling out to the north, slight cooler air will
advect into the area, resulting in lows in the mid to upper 40s for

.LONG TERM...(Monday through Saturday)
ISSUED AT 339 AM CDT Sun Mar 26 2017

The break in the precip overnight tonight will end quickly Monday
morning as another weak wave moves into the region.  An open wave
aloft, showers and thunderstorms will move in...mainly in a warm air
advection scheme...and much of the southern half of the state is in
a marginal/slight risk as the storms tap into mid afternoon air.
Ample lapse rates to support the potential for some isolated severe
storms, but much of the threat will rely heavily on the timing and
the coverage of the shower activity early. The track of the low in
both the ECMWF and the GFS is similar...and the NAM has fallen in
step with the qpf as well. Precip likely to come to an end in the
overnight hours.

A brief break in the precip for Tues and Wed as upper level ridging
keeps the region dry.  Easterly winds through both days results in a
rather neutral temp influence and max temps run very close to
climatological norms/degree or two above.  Dry run ends overnight
Wed into Thursday morning...and through Friday the next
deep low moves out of the desert SW and into the Midwest. However,
divergence in the ECMWF and GFS solutions after 90 hrs, leaves low
confidence in the details for the end of the week and going into the
weekend. Temperatures throughout the forecast are running a few
degrees above normal and well within end of March expectations.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1229 PM CDT Sun Mar 26 2017

No real significant periods of ceilings in the VFR range over the
next 24 hours, as low level moisture remains in place from the
departing system, and another quickly replaces it from the
southwest. Southern edge of the cloud shield may scrape areas
around KSPI/KDEC late afternoon or early evening, but chances
right now appear low enough to not mention in the TAF`s at this
point. MVFR conditions will prevail through a good part of the
evening, with IFR ceilings near KPIA for a couple more hours at
the start of the period. As an area of rain moves northeast
overnight, ceilings expected to fall below 1000 feet and should
encompass all of central Illinois by mid morning Monday.




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