Area Forecast Discussion
Issued by NWS Central Illinois
FXUS63 KILX 210831
Area Forecast Discussion
National Weather Service Lincoln IL
331 AM CDT Mon Apr 21 2014
ISSUED 330 AM CDT Mon Apr 21 2014
SHORT TERM...Today through Thursday night
00Z models in fair agreement next few days and have trended quicker
with moving cold front east of IL by overnight Thu night. Have
therefore lowered pops overnight Thu night.
First wx system to affect IL today and tonight is 1009 mb low
pressure just north of nw MN with its cold front into eastern NE
and central KS. Scattered showers and thunderstorms ahead of this
system over IA and western MO to spread east across IL during the
day and mainly holding off until the afternoon especially eastern IL.
Another mild day in the mid to upper 70s with mildest readings
over eastern IL as skies become mostly cloudy to overcast. Cold
front to sweep east across IL this evening with showers likely
along with a few thunderstorms this afternoon/evening. Rain
chances diminish by overnight and mainly east of I-57 early overnight
as skies clear from west to east overnight behind cold front. Lows
tonight range from mid 40s nw of IL river to near 55F se along the
Wabash river by Lawrenceville.
Weak high pressure ridge settles into IL by Tue evening and brings
fair skies Tue and Tue night along with cooler temps. Highs in the
low to mid 60s Tue/Wed with upper 60s se IL and sw areas. Lows
tonight 35 to 40 and could be some patchy frost over east central
IL where lows get in the mid 30s overnight Tue night with clear
skies and light winds.
A stronger storm system near the west coast to bring isolated waa
convection nw of IL river Wed and Wed night though better chances
with warm front to be further north of our CWA. Models consistent
is showing strong low pressure passing north of IL Thu/Thu night
though timing differences yet with passage of cold front, either
Thu afternoon or Thu evening. Likely chances of showers and
thunderstorms Thu and lingering over Thu evening especially
eastern IL. Will need to watch potential for strong to severe
storms Thu afternoon/evening.
LONG TERM...Friday through Monday
Dry conditions return Friday as models have shifted the wrap
around moisture further north by low pressure over WI/MI. So
removed the slight chance of rain showers ne counties Friday
with partly to mostly sunny skies. Highs Fri to range from the
mid 60s north of Peoria to the mid 70s se of I-70. Dry conditions
prevail Friday night and most of Saturday as clouds increase by
Sat. Highs Sat in the upper 50s from I-74 north to mid 60s se of
I-70. GFS is trending further south with next storm system early
next week and keeping central IL mostly dry Sun/Mon. ECWMF is more
aggressive in bringing moisture ne into central/se IL by early
next week. Will continue chance pops of showers and isolated
thunderstorms from Sat night through Monday. Highs Sunday similiar
to Sat highs while a bit cooler Monday with highs 55-60F.
ISSUED 1150 PM CDT Sun Apr 20 2014
VFR conditions will still prevail at all sites next 24hrs. Mid
clouds around 15kft will overspread the area overnight in advance
of the next system approaching from the west. As it gets closer
tomorrow morning, cigs will fall some, reaching to around 8kft.
Models indicate there could be some light showers or sprinkles
from this, but confidence is not very high given how dry the lower
levels are. So will just have VCSH for late morning at each site.
Then as the front gets closer, cigs will drop a little but will be
adding a scattered deck at around 3.5-4kft. Precip should be
ongoing and there is a chance that thunder could be there as well.
Again with dry surface levels, do not expect much reduction in vis
when showers are occurring. So only going with 6sm. As the front
moves in during the early evening hours, pcpn will end and
expecting cigs to rise back to around 10kft for remainder of the
night. Winds will be south to southwesterly overnight, but then
become west-southwesterly during the afternoon when the showers
arrive. West to northwest winds can be expected after the front,
though CMI will likely switch closer to 06z than the others.