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Area forecast discussion 
National Weather Service Lincoln Illinois
1047 am CDT Wednesday Jul 1 2015

issued at 1047 am CDT Wednesday Jul 1 2015

Made some quick updates to the forecast...mainly to lower probability of precipitation and
reduce thunder mention today. Overnight mesoscale convective system has tracked well to
the S/SW of central Illinois and is now pushing across southern
Missouri into western Kentucky. Further north...partly to mostly
cloudy but dry conditions prevail across the kilx County Warning Area. Will keep
an eye on scattered showers upstream across Minnesota into these will likely spill southeastward into the area
later today...but overall trend is drier than previously forecast.
Have lowered or eliminated probability of precipitation through midday...then gone with
mainly chance probability of precipitation for showers/isolated thunder from middle to late
afternoon. Best rain chances will hold off until tonight as low
pressure tracks from its current position over northern Kansas
into western Kentucky.


Short term...(today)
issued at 337 am CDT Wednesday Jul 1 2015

Surface boundary extending from southwestern Nebraska to central MO will be
the focus for showers and thunderstorms today. This will remain west
of the County Warning Area with most of the precipitation remaining southwest of the area
this morning. However...the boundary will begin to lift northward
during the additional showers and storms will develop
north of the boundary and effect central Illinois during the
afternoon. Higher probability of precipitation in the forecast will be to the southwest with
just a chance during the morning hours southwest of a Rushville to
Terre Haute, in line. During the afternoon this line with shift
northward to I-74 with likely probability of precipitation in the southwest and southeast.
Should be plenty of clouds to keep temperatures on the cooler
looking at afternoon highs only in the upper 70s. Winds this morning
will be light but then increase some for the rest of the day.
Northern parts of the County Warning Area will be north of the front all day so will
see easterly winds. South of the front winds will be southerly.

Long term...(tonight through tuesday)
issued at 337 am CDT Wednesday Jul 1 2015

This run of models has mixed news. The northern half of the state
may in fact see some partly cloudy and dry periods over the next
week...but the southern half of the state may not be as lucky. As a
result, the forecast is a bit troublesome from a persistence stand
point. Main issue with the forecast is the location of a quasi-
stalled boundary just to the south. A series of shortwaves interact
and keep precipitation off and on. Location of the boundary is what
remains an issue. All models are inconsistent and have continuity
issues between the quantitative precipitation forecast depiction and the surface frontal analysis in the
wind fields. Oscillating north and south in subsequent runs is not
helping to find any absolutes. So, for this forecast run, have
worked the forecast beyond tonight into slightly upping the probability of precipitation
across the south, particularly south of i70...but also some minor
increases in chance probability of precipitation south of i72.

Overnight, the highest probability of precipitation remain in the south with boundary
drifting slowly southward overnight and settling into the Ohio River
valley. For Thursday through Sat, have tried to keep the silent slight
probability of precipitation or none for areas immediately along and north of line roughly
from Springfield to Danville. To wrap up the weekend...the
superblend is hanging onto some chance probability of precipitation but have tried to temper
them somewhat as the wave at 500mb is broad, open, and producing
diff results between the European model (ecmwf) and the GFS. Monday night/Tuesday time
frame is when the agreement is starting to show even this far out
with a cold front sweeping through the region and more significant
probability of precipitation.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 647 am CDT Wednesday Jul 1 2015

Some light fog is effecting some sites this morning...but will
effect all sites for a couple have added a tempo group
for light fog until 14z. After this...basic conditions for all sites
will be some scattered cumulus around 4kft with an overcast middle deck
around 8kft. Models advertising scattered convection over some of
the sites for this afternoon and into this evening. So not think
the convection will get to pia and bmi. So have a thunderstorms in the vicinity with a
broken ceiling around 4kft for spi/Dec/cmi. Do not believe this will
last all night so have thunderstorms in the vicinity ending between 03 and 05z...from west
to east. Winds will be light this morning at all sites. Beyondthat...wind
direction will depend on where the front will be later today. So
have pia/bmi/cmi with easterly winds through the period. Spi and
Dec will see southwest winds this afternoon and then becoming
easterly tonight.


Ilx watches/warnings/advisories...


short term...auten
long term...hjs

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