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Area forecast discussion 
National Weather Service Lincoln Illinois
114 PM CDT Sat Oct 10 2015

issued at 1045 am CDT Sat Oct 10 2015
high pressure building back into the region today. Light northerly
winds, then variable as the ridge axis moves over central
Illinois. Plenty of sunshine under the subsident air, but temps
only climbing to the upper 60s/lower 70s. Forecast doing well. No
updates anticipated at this time.


Short term...(today)
issued at 243 am CDT Sat Oct 10 2015

Sunny and dry conditions can be expected today as high pressure
moves across the area. By afternoon, the high pressure should be
east enough of the area to allow southerly winds to return. These
southerly winds will allow temperatures to warm back to around
normal. Highs in the upper 60s to around 70 can be expected this

Long term...(tonight through friday)
issued at 243 am CDT Sat Oct 10 2015

Temperatures will be a roller-coaster ride over the next few days,
before the upper pattern transitions to a more persistent northwest
flow and a steadier period of cooler temperatures mid to late week.
Sunday will be the warmest day of the period, with highs around 80
degrees across much of the western half of the County Warning Area. Similar
temperatures may occur south of I-70 on Monday before the arrival of
a cold front.

Main period of concern will be on Monday. Upper level wave currently
west of British Columbia will be coming onshore this evening and zip
across the Canadian rockies before closing off a low over southeast
Saskatchewan Sunday evening. This feature will continue to deepen as
it tracks near or just north of the Minnesota/Ontario border Sunday
night and Monday. There is general model agreement that the trailing
cold front will be racing across the forecast area Monday morning
and be past the area before any sort of precipitation forms.
However, the strong cold air advection will result in rather windy
conditions. GFS BUFKIT soundings for Peoria show winds of 40 knots
mixing down in the afternoon, resulting in surface gusts of 30-40
mph, while the NAM is a bit tamer with 25-30 mph surface gusts. The
latest European model (ecmwf) model is further south with the upper low, tracking it
over Lake Superior while the remaining models lift it northeast
through Ontario, and thus is a bit less windy as well. Currently am
leaning more toward the nam's wind speeds and will carry some gusts
near 35 mph around Galesburg, with mainly 25-30 mph over the
remainder of central Illinois.

Model divergence starts to set up toward late week, as the latest
European model (ecmwf) model digs a fast-moving shortwave into our area toward Friday
morning accompanied by scattered showers. The GFS meanwhile has high
pressure settling southeast through the Midwest. The European model (ecmwf) solution
is quite a bit slower than its previous run, which had this wave all
the way into Ohio by Friday morning (vs just west of I-55 on the
latest run). With the inconsistency, will maintain a dry forecast
for now.


Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 112 PM CDT Sat Oct 10 2015

VFR throughout the taf pd. Looking at cirrus streaming through the
Midwest on visible imagery. High pressure ridge axis over the
region allowing for some variability in light winds. Winds should
become increasingly south/southwesterly in the overnight hours and
gusty tomorrow.


Ilx watches/warnings/advisories...


short term...auten
long term...geelhart

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