Area Forecast Discussion
Issued by NWS Central Illinois
FXUS63 KILX 201438
Area Forecast Discussion
National Weather Service Lincoln IL
938 AM CDT Sun Apr 20 2014
ISSUED 937 AM CDT Sun Apr 20 2014
Main forecast concern today is with temperatures. 9 am readings
running a few degrees higher than the forecast curve, with most
areas already in the lower to mid 60s. Have only had some patches
of cirrus moving by, and southerly winds a bit higher than first
thought. Latest HRRR/RAP guidance suggesting lower 80s widespread
by mid afternoon, but there is also a decent size area of mid and
high clouds spreading northeast which could hamper things. Blended
in some of the LAMP guidance which resulted in highs 78-80 across
the Illinois River valley, which is just a tad higher than what
has been going.
Updated grids have been sent. New zone forecasts to follow, mainly
to adjust the wording of the sky cover.
ISSUED 625 AM CDT Sun Apr 20 2014
VFR conditions are expected through 12z Monday. High pressure
to our east will allow a southerly flow to prevail today and
tonight with speeds in the 10 to 15 kt range thru the daylight
hours, and then decrease to 5 to 10 kts tonight. Forecast
soundings showing quite a bit of high level moisture in the
15,000-20,000 foot range this period with some lowering of the
cloud bases to around 10,000 feet by the end of this forecast
period, mainly across the far western portion of the TAF area.
ISSUED 330 AM CDT Sun Apr 20 2014
SHORT TERM...Today through Tuesday night
Another beautiful day ahead on this Easter Sunday across central &
southeast IL with passing mid/high clouds giving partly to mostly sunny
skies with ESE winds turning south by afternoon at 8-15 mph. Like
the past two days, went 1-2 degrees above guidance highs today.
850 mb temps that were at 9C at sunset yesterday elevate to 10-11C
this afternoon and supports highs of 75 to 80F with warmest
readings in western areas. 1034 mb high pressure over Quebec was
ridging SW into the mid MS river valley while upper level ridge
was from east Texas into the OH river valley. Surface and upper
level high pressure ridge will be very slow to pull away from the
region due to blocking cutoff mid/upper level low off the SC/GA
coast. So continue a dry forecast tonight across CWA as mid/high
clouds continue to increase. Mild lows tonight in the low to mid
Stronger northern stream system moving east across southern Canada
to pull a cold front SE across central/SE IL during Monday night
while weak short waves eject into IL from the central plains. Have
chances of showers and isolated thunderstorms spreading eastward
across IL during the day Monday and then diminishing from the west
behind the cold front during Monday night. Weather system is weak
and limited instability so thunder chances appear slim at this time.
Warm highs in the mid to upper 70s Sunday with Robinson and
Lawrenceville by the Wabash river near 80F. Lows Monday night in
the upper 40s and lower 50s, with mid 50s near the Wabash river.
Cooler highs in the low to mid 60s Tue and Wed as high pressure
near the Pacific coast settles into the region Tue night. Mostly
sunny skies Tue with more cumulus clouds over eastern IL into IN.
Tue night to be the coolest night as skies clear and winds
diminish with some upper 30s over NE areas by dawn Wed.
LONG TERM...Wednesday through Sunday
High pressure drifts east of IL Wed with strong low pressure
system moving east across the northern Rockies near the Canadian
border. Some WAA isolated convection possible over NW counties by
afternoon into Wed night with better chances further NW toward
northern IL, IA and WI. Convection chances increase from west to
east during Thu with best chances Thu afternoon/evening strong
storm system pushes cold front east toward MS river by sunset Thu
and thru IL Thu night. Slight chance of showers Fri morning. Highs
in the upper 60s to mid 70s Thu/Fri though mildest readings shift
into SE IL Fri. Cooler and drier wx Fri night and Sat. Then return
chances of showers and possible thunderstorms by overnight
Saturday night into Sunday next weekend with low pressure and warm
front approaching IL from the SW.