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fxus63 kilx 302008 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
308 PM CDT sun Apr 30 2017

Short term...(this evening through monday)
issued at 307 PM CDT sun Apr 30 2017

Continued the Flash Flood Watch east of the Illinois River through 7 am
CDT Monday, and Peoria and Marshall counties were also added. An
area of light to moderate showers spread northward across central Illinois
today while the thunderstorms were mainly east over in and western
Kentucky. Storm Prediction Center day1 late morning update shifted the slight risk of severe
storms east of the Wabash River, while still having a marginal risk
of severe storms over central and eastern Illinois. A band of convection
was developing along the cold front in central MO and ahead of 996
mb surface low pressure in central Kansas. This line of developing
convection should spread eastward across County Warning Area during this evening
with the cold front. Between a half and 1 inch of rain is possible
during this afternoon and evening, before showers and thunderstorms
chances diminish overnight behind cold front. Lows tonight to range
from mid to upper 40s over western County Warning Area and lower 50s in eastern Illinois.

A strong 538 dm 500 mb low over south central Kansas will eject
northeast to near Door County WI by 7 PM Monday. This will keep low
clouds around along with chances of light rain showers especially
north of I-70. Cooler highs in the lower 50s northern County Warning Area and upper
50s in southeast Illinois. Windy on Monday with SW winds gusting 30-35
mph.

&&

Long term...(monday night through sunday)
issued at 307 PM CDT sun Apr 30 2017

12z models take strong cutoff upper level low NE into eastern Canada
on Tue while weak surface high pressure ridge moves into the MO
valley. After isolated light rain showers over NE County Warning Area Monday
evening, dry wx expected with decreasing clouds and winds overnight
Monday into Tue. Cool lows Monday night of 39-45f with highs Tue
near 60f from I-74 north and upper 60s in southeast Illinois.

Models still deepen an upper level trof over the central and
Southern Plains Wed and into the mid/lower MS River Valley on Thu.
Models have trended a bit slower bringing qpf into southern areas
later Tue night and more likely on Wed and Wed night. Still some
question on how far north shower chances get and stayed close to
consensus model solutions with northern County Warning Area drier and higher pops in
southern County Warning Area. Thunderstorms chances still appear to be south of County Warning Area
on Wed afternoon/evening. Highs Wed in the upper 50s to around 60f
with more cloud cover. Highs Thu in the upper 50s/lower 60s with
coolest readings in east central and southeast Illinois where lingering
chances of light rain showers.

Models differ with handling deepening upper level trof and cutoff
low in the southeast states Thu night and Friday and consensus kept
slight pops in southeast Illinois along with more clouds and cooler temps
there with lower 60s Fri while mid 60s from I-55 west. Next weekend
looks drier over County Warning Area as weak surface high pressure ridge settles
into area. Highly amplified upper level flow over the country with
cutoff lows and deep trofs over the northeast U.S. And western
states while upper level ridge in between over the Great Plains.
Slowly moderating temps next weekend with highs in the upper 60s Sat
and upper 60s/lower 70s next Sunday which is closer to normal for
early may.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1255 PM CDT sun Apr 30 2017

A warm front near I-72 will lift toward the Illinois River by pia during
this afternoon and spread an area of showers and a few
thunderstorms northward from I-72 to pia and bmi. Ceilings of
200-500 ft at bmi, pia and spi should lift to MVFR by mid or late
afternoon as warm front lifts northward. Deepening 996 mb surface
low pressure over central Kansas will lift NE to central Iowa by 06z/1
am tonight and deepen to 990 mb over northcentral Illinois by early
Monday afternoon. This will swing a cold front east over central
Illinois during this evening with showers/thunderstorms ending behind
the front. Some light rain showers are expected on Monday
especially at bmi and pia with MVFR ceilings. East-northeast winds at pia and
bmi will switch to the south-southeast during the afternoon and then SW during
tonight into Monday. Winds will gusts to 20-35 kts at times this
afternoon and again on Monday.



&&

Ilx watches/warnings/advisories...
Flash Flood Watch through Monday morning for ilz029>031-037-038-
041>050-052>057-061>063-066>068-071>073.

Flash Flood Watch through Monday evening for ilz051.

&&

$$

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