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Area forecast discussion 
National Weather Service Lincoln Illinois
621 am CDT Tuesday Oct 13 2015

Short term...(today)
issued at 258 am CDT Tuesday Oct 13 2015

With high pressure ridge in the plains, surface cyclonic flow will
continue across the County Warning Area today. Satellite loops shows some clouds
moving across northern IL, effect northern parts of the County Warning Area early
this morning. Based on trajectory of these clouds, believe these
clouds will effect areas along and north of I-74 this morning.
Satellite loop also shows high cirrus clouds across northern US that
should advect into the area during the day. So thinking is partly
sunny skies in the north with mostly sunny skies elsewhere. Highs
this afternoon will be in the middle to upper 60s, which is right at
normal for mid October. Northwest winds will also continue over the
area but gusts will not be as strong as they were yesterday.

Long term...(tonight through monday)
issued at 258 am CDT Tuesday Oct 13 2015

Main issues for this part of the forecast include the rain chances
on Thursday and the chilly weather that will follow for the weekend.

Upper flow starting to come more out of the northwest, as the upper
low tracks slowly east across Lake Superior early this morning. Fast-
moving shortwaves will zip along in the flow. The first one will
pass through the forecast area tonight with little more than a wind
shift, but the stronger one is still poised to come through in the
Thursday afternoon/evening time frame. The amount of precipitation
with this system continues to be a challenge, with the European model (ecmwf) -- once
again -- being the only model to show any sort of rain in central
Illinois with the frontal passage. With an easterly surface flow
over the Gulf of Mexico, there really isn't any sort of moisture
advection beyond what is already present with the system, so will
limit rain chances to only the 20% range and mainly Thursday

A cool period is on tap for the weekend, as the broad upper trough
holds across the Midwest and 850 mb temperatures fall below zero.
Dry air will drop dew points into the 20s by Saturday. This should
allow temperatures Friday and Saturday nights to fall pretty deep
into the 30s, and some freezing temperatures may occur in the
normally colder regions. With clear skies prevailing, have added
some mention of frost across the forecast area both mornings. A
warming trend will begin on Sunday, as a southerly return flow sets
up behind a surface high that will be drifting east out of our area.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 621 am CDT Tuesday Oct 13 2015

VFR conditions will prevail at all taf sites next 24hrs. Broken to overcast
clouds around 3.5kft are covering pia/bmi/cmi early this morning.
These clouds are moving east and southeast so should move away
from the tafs later this morning around 16z. Then, based on
satellite trends and relative humidity fields from the models, cirrus will advect
over the area for the rest of the morning and into the afternoon.
Then clear skies expected tonight after sunset. Winds will be
northwest through the period, with some gusts late this morning
through afternoon...though not as windy as yesterday.


Ilx watches/warnings/advisories...


Short term...auten
long term...geelhart

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