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Area forecast discussion 
National Weather Service Lincoln Illinois
646 am CDT sun Aug 2 2015

Short term...(today)
issued at 331 am CDT sun Aug 2 2015

High pressure ridge is oriented from eastern OK...northeastward into
the Ohio River valley...while a cold front is located over the
northern plains/miss valley. This front will drop slowly south
today. Models poorly handled things yesterday/last evening so have
low confidence in any model solution for today. High res models
continue to bring in some scattered convection into the area this
morning and then have it moving east and then dissipating in the
afternoon. Some convection has developed well ahead of the front
extending from WI southwestward through Iowa and into Nebraska. These
thunderstorms are in an area with better low level moisture and with
highest dewpoints in Iowa...thinking is that the precipitation will continue the
remainder of the night as it moves east/southeast. Some of this
could get into the County Warning Area so will have slight chance probability of precipitation in the
northwest/north for this morning. Outflow from these storms could be
the focus for more storms for the afternoon/during maximum heating.
Therefore have chance probability of precipitation in the afternoon in the northern third of
the County Warning Area. With more southwesterly winds today and mostly sunny skies
into the afternoon...afternoon high temperatures should once again be in
the upper 80s to around 90.

Long term...(tonight through saturday)
issued at 331 am CDT sun Aug 2 2015

Isolated to scattered convection expected to develop over northern
County Warning Area mainly north of I-72 during this afternoon to gradually shift southeast
during tonight with highest probability of precipitation over northern County Warning Area late this
afternoon and this evening. Storm Prediction Center has slight risk of severe storms
this evening over from Galesburg to Peoria to Bloomington and
Hoopeston north where 15% risk of damaging winds and large hail
along with 2% risk of tornadoes. Storm Prediction Center has enhanced risk of severe
storms over NE Illinois closer to Rockford and Chicago metropolitan area where
stronger forcing will be and steeper lapse rates as short wave
tracks across WI/mi. Frontal boundary to push southeast across central Illinois
overnight into Monday morning and weaken into southeast Illinois Monday
afternoon. Isolated showers/thunderstorms possible south of I-70
Monday afternoon but better forcing will have shifted east of southeast Illinois
by then into southeast parts of Ohio/in and northern Kentucky. Lows tonight in the
upper 60s with Galesburg around 65f. Highs Monday in the middle to upper
80s but range from lower 80s by Galesburg to 90f by Lawrenceville
where afternoon heat indices in the middle 90s. Generally dry
conditions expected Monday night again with just slight probability of precipitation far SW
County Warning Area closer to frontal boundary south of area over northern Kentucky into
central MO.

00z forecast models show more active weather pattern during middle and
late work week as Illinois is established in a west-northwest upper level flow
with large upper level low over NE Canada and upper level ridge
over the southern rockies. Short waves tracking east near frontal
boundary during middle of the week with increasing chances of
showers and thunderstorms...mainly SW areas Tuesday and across area by
Wednesday and Wednesday night with likely probability of precipitation over parts of east central and
southeast Illinois then. Best chances of showers and thunderstorms shift
southward by Friday with most of area dry by next weekend. Highs
in the low to middle 80s Tuesday to cool into the upper 70s/lower 80s
from Wednesday through rest of the week which is below normal for early


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 646 am CDT sun Aug 2 2015

Models have done poorly with the location and timing of the precipitation
into the area...but still looks like two times of possible
convection at each taf sites today. Storms in southern Iowa look
to be moving east-southeast toward the area so think later this
morning storms could effect each site. Given uncertainty with
placement of storms...will have thunderstorms in the vicinity in the forecast for two
hours. Then next round will be after 00z as the cold front drops
into the area from the north. Again due to location
uncertainty...will just have thunderstorms in the vicinity for later this evening for all
sites. Do not see any restrictions on visible or ceilings below 3kft so
VFR conditions will prevail next 24hrs. Winds will be
southwesterly through the period and think some gusty winds near
20kts will be possible this afternoon and early evening.


Ilx watches/warnings/advisories...


Short term...auten
long term...07

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