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Area forecast discussion 
National Weather Service Lincoln Illinois
311 am CDT Wed Apr 1 2015

Short term...(today)
issued at 310 am CDT Wednesday Apr 1 2015

Strengthening southerly flow will develop across central Illinois
today ahead of low pressure deepening eastward into the northern
plains and upper Midwest. Warm advection in the southerly flow will
result in temperatures reaching the low 70s most areas, with mid 70s
from around Springfield to Peoria westward. South winds will become
quite breezy for the afternoon, reaching around 20 mph and gusts to
30 mph from I-55 westward. To the east, winds should be a more
subdued 15 mph with gusts 20-25 mph. Aside from scattered high
clouds, the day should be mostly sunny as significant lift and
instability with the approaching low/cold front hold off until


Long term...(tonight through tuesday)
issued at 310 am CDT Wednesday Apr 1 2015

Overnight lows fairly consistent across the guidance as clouds come
in and southerly flow continues through the overnight. Tightening
pressure gradient ahead of approaching cold front will keep the
winds and associated warm air advection up a bit overnight. Models still having an
issue with consistency of timing of precip...with some wavering
back and forth on showers well ahead of the boundary itself. After
12z, rain showers and some thunder will move through the region
invof the cold front dragged behind the sfc low crossing over the
srn tier of Canada. Enough cloud cover and preliminary qpf should
provide some limitation to the developing instability...with areas
southeast of roughly the I-72 corridor getting more sun/daytime heating
with the boundary moving through later in the afternoon/early
evening. This plays to the area being in a slight risk for severe
weather on spcs day 2 outlook, mainly as a wind and hail threat.
Front still expected to slow considerably moving southeast of the area
becoming quasi-stationary as another wave moves out of the Southern
Plains and rides along the boundary, spinning up another storm
system for along and north of the Ohio River valley. Northern
extent of the quantitative precipitation forecast through Friday will be highly dependent on the
southward progression of the frontal boundary. Previous model runs
have had much cooler temperatures in place for Friday afternoon and
threatening snowfall in a deformation zone setting up along the
Illinois River valley. However, most recent models too warm and
backing off from that solution, and will refrain from bringing that
into the grids just yet.

High pressure takes over for much of the weekend as temps start a
brief warming trend with a dry forecast. Short-lived mild weather
ends going into an unsettled work week as the models are bringing in
a warm advection look ahead of the next storm system moving out of
The Rockies. Prolonged period of qpf through Tuesday and
potentially into Wednesday from the storm system itself and the
boundary associated getting hung up in parallel flow as
southwesterly flow sets up over the Continental U.S. For midweek.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1100 PM CDT Tuesday Mar 31 2015

VFR conditions will prevail thru this forecast period (06z thu).
Little change expected across the area through tomorrow morning
as surface high pressure shifts off to our east. As the high
pushes further away Wednesday morning, look for surface winds
to increase out of the south and be rather gusty during the
afternoon and early evening hours. South winds of 12 to 17 kts
can be expected after 16z tomorrow with gusts up to 25 kts psbl
during the afternoon and early evening hours. A cold front will
be well off to our northwest tomorrow and then edge slowly towards
our area by Thursday morning. Showers and thunderstorms along the
frontal boundary will also approach our western taf sites but not
until after this forecast period, more towards the 09z-12z time
frame Thursday morning.


Ilx watches/warnings/advisories...


Short term...Onton
long term...hjs

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