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Area forecast discussion 
National Weather Service Lincoln Illinois
1155 PM CDT Wed Apr 1 2015

issued at 904 PM CDT Wednesday Apr 1 2015

Current forecast looks OK for now. Will make some minor changes to
the some of the grids, but overall no changes planned.


Short term...(tonight)
issued at 300 PM CDT Wednesday Apr 1 2015

A tight pressure gradient between a large high over the eastern
Great Lakes and a cold front across the northern plains will
continue to create strong southerly winds across central Illinois
tonight. Forecast soundings and numeric guidance suggest sustained
winds of 10 to 15mph will prevail throughout the night. These
southerly winds combined with increasing cloud cover will produce a
much warmer night than has recently been seen, with overnight low
temperatures remaining in the 50s. The cold front will slowly
approach from the west, but is expected to remain west of the
Mississippi River until Thursday morning. Meanwhile, a short-wave
trough evident on 18z/1pm water vapor imagery over eastern Oklahoma
will track northeastward into Illinois tonight. Showers and
thunderstorms currently ongoing with this feature across the Ozarks
will lift/spread northeastward as well. GFS/NAM/rapid refresh all
indicate scattered showers/thunder arriving in central Illinois from
late evening into the overnight hours. With an initially very dry
airmass in place, think a slower arrival of precip is likely. Have
therefore kept the evening mostly dry, with chance pops coming into
the picture after midnight.


Long term...(thursday through wednesday)
issued at 300 PM CDT Wednesday Apr 1 2015

Unsettled weather pattern over Illinois Thu through Friday. Storm Prediction Center has areas
along and south of a Shelbyville to Paris line in a slight risk of
severe thunderstorms Thu afternoon after 18z/1 PM into early Thu
evening until dusk. Short wave lifts NE of central Illinois Thu morning
while cold front pushes se toward the Illinois River valley by 18z/1 PM
Thu and south of I-72 by 00z/7 PM Thu. Increasing moisture/dewpoints
into 55-60f range Thu and convective available potential energy peaking from 1000-1800 j/kg Thu
afternoon and early evening south of I-72 supports a marginal to
slight risk of severe storms for gusty winds and possible large hail
with a few storms. Last time we had severe storms in our County Warning Area was Oct
13th and our NE counties have not had thunderstorms since Veterans
Day morning Nov 11th. Another mild day Thu with highs in the upper
60s to near 70f over central Illinois and lower 70s in southeast Illinois.

Cold front to push se across southeast Illinois during Thu night keeping
high chances of showers and chances of thunderstorms going from I-72
south with lower chances of showers north of I-72. Surface low
deepening along the front near the Ohio River Friday to keep high
chances of showers and few thunderstorms in southeast Illinois with good
chances of showers over the Illinois River valley and showers chances
increase northward with passing surface low to our south/se. Storm Prediction Center has
slight chance of severe storms in far southeast Illinois Friday south of
I-64. Have slight chances of showers Friday evening in eastern Illinois
with perhaps a chance of light snow mixed in with the light rain in
east central Illinois but no accumulations. Cooler highs Friday around 50f
northern counties and 55-60f in southeast Illinois with temps slipping
during the afternoon with breezy NNW winds. Between 1.5-2 inches of
rain expected over southeast Illinois with locally higher amounts south of
Highway 50, but these amounts are below flash flood guidance values
around 2 inches per hour, so holding off on issuing any flood

Quiet weather still expected Saturday and Sunday with more sunshine
as high pressure settles into Tennessee by sunset Saturday. Lows Fri night
in the lower 30s. Highs Sat in the 50s with mildest readings in
western Illinois. Breezy south winds Sunday warms highs into the low to
mid 60s as high pressure slips off the Carolina coast by Sunday

Unsettled weather pattern returns Monday-Wednesday with daily
chances of showers and thunderstorms with SW upper level flow over
Illinois. European model (ecmwf) model is much wetter Tue night through Wed night while GFS
model is dry so some differences here to resolve and stuck close to
blended guidance pops. Highs in the low to mid 60s again on Monday
and upper 60s and lower 70s Tue. Then cold front pushes se through
Illinois Tue night and Wed with cooler highs Wed of 55-65f and mildest in
southeast Illinois.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1155 PM CDT Wednesday Apr 1 2015

VFR conditions will continue at all sites next 24hrs. However,
light showers will advect into the area very soon and spread
northeast. They could effect all sites, but area seems to be
remaining in western Illinois. Will have predominate showers at pia and
spi and then just vcsh at Dec, cmi, and bmi. Thunderstorms are
still embedded in the area on the back side and based on
direction, looks like spi and pia could see some, so will just
have thunderstorms in the vicinity at those sites. Later this morning, the cold front,
located in Iowa/neb, will move into the state and bring more showers
and thunderstorms to the sites. All sites should see these arrive
sometime during the morning hours, with spi and pia first. Will
keep the predominate rain and thunderstorms in the vicinity for all tafs. Pcpn should end
once frontal passage occurs and cigs should get higher as well. Frontal passage should
occur sometime during the afternoon to late afternoon hours from
west to east. Evening conditions should be some mid clouds around
12kft. Will keep the low level wind shear at all sites overnight, until morning
time frame. Sfc winds will be southerly and then become southwest
during the day, then northwest after frontal passage. Winds will be gusty
during the day and then decrease after frontal passage.


Ilx watches/warnings/advisories...


short term...Barnes
long term...07

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