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fxus63 kilx 231026 

Area forecast discussion
National Weather Service Lincoln Illinois
526 am CDT sun Jul 23 2017

Short term...(today and tonight)
issued at 255 am CDT sun Jul 23 2017

Earlier convection that occurred generally along and east of I-57
late evening and past midnight has largely pushed into Indiana as
of 2 am. Currently watching a large mesoscale convective system advancing across Missouri.
Trajectory of this would generally keep it south of I-72 as it
begins to move into western Illinois, with the hrrr showing a
diminishing trend as the remnants make it over to about Flora and
Effingham toward 7 am. Storm Prediction Center mesoanalysis still showing cape's over
3000 j/kg at this early hour ahead of the MCS, with dew points at
Springfield almost 80 degrees at 2 am. As the day GOES on, the
highest cape will shift over into southeast Illinois, as some
lower dew points start to advect into areas northwest of the
Illinois River. However, as the cooler air lags further behind,
temperatures reaching the lower 90s will still result in
significant instability over the northern County Warning Area this afternoon. Will
maintain the mention of scattered storms this afternoon and
evening across the forecast area, as the cold front settles across
the region. Can't rule out a few severe storms as 0-6km shear is
modest over the area (around 30-35 knots).

Long term...(monday through saturday)
issued at 255 am CDT sun Jul 23 2017

Quiet weather will dominate the first few days of the work week,
as high pressure drifts across the Great Lakes. The northeast
circulation into our area should keep dew points in check, mainly
mid 60s, through Tuesday. After that, the Gulf moisture flow kicks
back in as the upper level high builds eastward back into the
mid-Mississippi Valley. A strong upper low, currently seen in
early formation over northern British Columbia, will keep the
ridge from amplifying too much over US, so after a quick shot of
hot and humid weather, the upcoming end of week looks more

The main concern for precipitation will be Wednesday night into
Thursday, as the cold front trailing the upper low moves through
the area. The GFS introduces some scattered storms as early as
Wednesday afternoon as a weak wave moves through, but the European model (ecmwf)
focuses on the main front itself late Wednesday night into
Thursday. In either case, it should take until late Thursday
evening before the front fully crosses the forecast area, and will
keep healthy chance pop's going south of I-72 into the evening.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 526 am CDT sun Jul 23 2017

Line of strong/severe storms that moved out of Missouri has stayed
south of the taf sites. Lower clouds down to around 3500 feet have
reached up into central Illinois at times, although kcmi had a
brief period of IFR ceilings.

Main concern later in the day will be with a cold front moving
into the area. Scattered storms possible from about 22z-03z, and
have mentioned thunderstorms in the vicinity at all taf sites during this period. The
storms should fade around sunset, with quiet weather the rest of
the period.


Ilx watches/warnings/advisories...

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