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Area forecast discussion 
National Weather Service Lincoln Illinois
343 am CDT Tuesday may 26 2015

Short term...(today)
issued at 343 am CDT Tuesday may 26 2015

Low clouds have been advecting into the area and will remain over
the area this morning. Lower clouds indicating lots of low level
moisture being advected into the area ahead of the weather system
that still is west of the County Warning Area. Radar and satellite loops show
several mcvs west of the area with some showers moving north through
southeastern MO. Models continue to indicate precipitation redeveloping
today. Clouds will limit the degree of instability but still
expecting enough for thunderstorms, just not enough for anything
severe, which should be east and southeast of the area where less
clouds will be. Cloud cover will also temper warm up as well so only
expecting upper 70s for highs which is much less than past two days.
Probability of precipitation will be a gradual increase today reaching likely later this
morning and then moving north and east this afternoon, becoming
chance category by late afternoon as the precipitation moves east of the
area. Southerly winds will be a tad gusty again, just not as much as


Long term...(tonight through monday)
issued at 343 am CDT Tuesday may 26 2015

Until the upper wave pulls into the Great Lakes region, lingering
probability of precipitation will remain over the forecast area for this evening. Better chances will
remain to the east overnight. Remains of the front will stall out
along the Ohio River valley and provide a bit of focus for another
piece of energy ejecting out of the southwest. Models differing
with the northerly extent of the precip, but last few runs bringing
in some precipitation for Wednesday in the southeast. NAM is a
little more widespread, but concentrating the probability of precipitation to the south and
east for now. Timing issues remain in place for this synoptic run
for the next system quick on the heels as the deep wave over the SW
starts to move out into the plains. Convection and precipitation starts to
spread over the eastern half of the country in the models with weak
southwesterly flow aloft shifting to weak flow overall. Warm and
muggy conditions continue in a more summerlike airmass throughout
the week...but that next system will bring a cold front into the
region for the first half of the weekend to focus the rain, with a
cooler airmass behind it dropping the temperatures for the weekend out of
the 80s for a couple days.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1151 PM CDT Monday may 25 2015

VFR conditions in scattered high cloud cover with south winds
10-12 kts this evening across central Illinois. High cloud associated
with a shortwave over northeast Oklahoma will continue moving into
the region overnight. Current timing of lift and moisture with
the approaching shortwave indicate predominant MVFR conditions in
rain showers/isolated thunderstorms and rain likely to begin 10-12z. Some lifting of
predominant ceilings likely in afternoon with daytime heating and
according to model time-height sections so have included thunderstorms in the vicinity
with ceilings above MVFR threshold. Shortwave axis expected to cross
late afternoon/early evening Tuesday bringing a decrease in
shower/thunderstorm activity by 00z and have ended thunderstorms in the vicinity and 4 kft
above ground level ceilings. Winds continuing S 10-12 kts until 14z...increasing to
15-20 kts with gusts 25-30kts and shifting toward SW. Winds
decreasing after 00z.


Ilx watches/warnings/advisories...


Short term...auten
long term...hjs

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