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fxus63 kilx 181111 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
611 am CDT Wed Sep 18 2019

Synopsis...
issued at 324 am CDT Wed Sep 18 2019

After an extended period of warm and dry weather through the
remainder of the work week, the next significant chance for
widespread rain will arrive by the weekend.

&&

Short term...(today and tonight)
issued at 324 am CDT Wed Sep 18 2019

High pressure extending from Quebec southwestward into the Midwest
is providing mostly clear skies and light winds across central
Illinois early this morning. Some minor visibility restrictions
have occasionally been noted north of the I-74 corridor over the
past couple of hours: however, think enough mixing occurred
yesterday afternoon to prevent widespread fog development. Have
therefore only mentioned patchy fog across the northern kilx County Warning Area
until shortly after sunrise. After that, mostly sunny and very
warm conditions will prevail today with afternoon highs once again
topping out in the middle 80s. Lows tonight will drop into the
lower to middle 60s under mostly clear skies.

Long term...(thursday through tuesday)
issued at 324 am CDT Wed Sep 18 2019

Upper ridging will hold firm across the Midwest/Ohio River valley
through the end of the week, ensuring a continuation of above
normal temperatures well into the 80s through Friday. A deep upper
low evident on latest water vapor imagery over the Pacific
northwest will eventually shift eastward and flatten the ridge,
but this process will not occur until the weekend. 00z Sep 18 GFS
appears to be overly aggressive with scattered precip development
on Friday as boundary layer moisture begins to increase. With
significant forcing still well to the northwest and moisture
associated with the remnants of tropical storm Imelda to the
southwest, have limited pops to just just slight chance
along/west of I-55.

As deeper moisture arrives courtesy of Imelda, think scattered
showers and thunderstorms will develop on Saturday...especially
west of the I-57 corridor. Once the Pacific northwest wave and its
associated cold front slowly push into the area and intercept this
moisture, widespread precip will develop Saturday night through
Sunday night. Models continue to indicate impressive precipitable
water values in excess of 2 inches, suggesting the potential for
locally heavy rainfall. At this time, will carry likely pops late
in the weekend...with storm total rainfall of 2 to 3 inches
everywhere north of I-70 by Monday morning. Most models agree that
the wave will pass through the region and push the front south of
the Ohio River by Monday...resulting in cooler/drier weather at
that time.

&&

Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 611 am CDT Wed Sep 18 2019

VFR conditions will prevail at all taf sites next 24hrs. There
could be some light fog this morning at spi/Dec/cmi of around
4-5sm, but will just handle this with a 1hr tempo group. Pia
temp/dwpt spread is large enough and bmi winds are high enough,
that do not think either site will see fog this morning.
Otherwise, all sites will just have few cirrus through the day and
into the night. Winds will be light east-southeast through the
period as well.

&&

Ilx watches/warnings/advisories...
none.
&&

$$

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