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fxus63 kilx 160910 

Area forecast discussion
National Weather Service Lincoln Illinois
410 am CDT Tue Jul 16 2019

Short term...(today and tonight)
issued at 340 am CDT Tue Jul 16 2019
remnant low associated with what was previously Tropical Storm
Barry centered over south central MO this morning, with bands of
precip pushing into Illinois. Bands of precip on radar slow with
northerly progression as they erode slightly. Barry has turned out
to be a little less efficient with precipitation than previously
thought and central Illinois at least has been pulled from excessive
rain outlooks. The persistent cloud cover is also further
inhibiting severe threat, though a thunderstorm or two will
remain possible. Generally speaking, the lapse rates are meager at
best, and thunder may be sparse until the afternoon, when some
diurnal swing will help steepen the llvl lapse rates and influence
MUCAPES. Overall, a muggy day for central Illinois. Those precip chances
will continue into the overnight hours until Barry moves out to
the NE by Wed morning. Residual moisture, light winds, and
potentially clearing skies are setting up for some fog potential,
highest across the half of the state. Not an absolute by any
stretch, but putting in a patchy mention for now.


Long term...(wednesday through monday)
issued at 340 am CDT Tue Jul 16 2019
Wednesday begins an extended dry period in the forecast once the
remains of Barry move out to the NE. Warmer on Wednesday, but
held to the upper 80s/90s, just the beginning for the heat that
follows. With plenty of llvl moisture in place, heat indices will
push 100f in a few locations starting Wednesday. That heat expands
and ramps up from Thursday through the weekend. Heat indices
approaching 110f for several days warrants the excessive heat
watch that will likely need to be expanded to encompass all of ilx
County Warning Area. However, a couple of things will potentially threaten the 4
day heat wave. Need to watch for mesoscale convective system activity to the north... and
the timing of a frontal system being dragged through the region on
Sunday. Either way, hot and muggy is most definitely the major
story for the forecast run. The extended time frame of the event
will bring an increased risk. Major flaw in the blended models at
this point is the far, showing no sign of the
frontal system sun/Sun night and beyond. Temperatures cooler on
the other side of Sunday likely dropped considerably by
climatology. Safe to say that there is little confidence in this
particular forecast run beyond Saturday.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1122 PM CDT Mon Jul 15 2019

Low pressure associated with the remnants of Hurricane Barry will
lift across central Illinois during the day Tuesday. Ahead of the
low, south to southeast winds will prevail and a few bands of
light showers will lift across central Illinois overnight. MVFR
ceilings are already in place across portions of west central
Illinois and are expected to spread east across central Illinois
overnight. IFR may occur for a few hours at the terminals Tuesday
morning, then should lift back to MVFR by around midday. There
will be periodic waves of showers through much of the period, but
a few thunderstorms are also possible, especially during the
afternoon and early evening hours Tuesday when instability is
maximized. Precip coverage may remain scattered, so for now will
cover with vcsh until there is higher confidence in specific
precip timing. Winds will go light and variable later in the day
as the low tracks across the region, then precip chances should
taper off in its wake.


Ilx watches/warnings/advisories...
excessive heat watch from Wednesday afternoon through Saturday
evening for ilz027>031-036-037-040>042-047>052.


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