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Area forecast discussion 
National Weather Service Lincoln Illinois
331 am CDT sun Apr 26 2015

Short term...(today)
issued at 330 am CDT sun Apr 26 2015

Low clouds continue to gradually work their way south through
central and east central Illinois early this morning as drier air
advects from the northeast. Mostly cloudy conditions will linger
in southeast Illinois from daybreak until mid-morning. Plenty of low
level mixing in the lower atmosphere late this morning through the
afternoon will result in northeast winds gusting close to 20 miles per hour
especially east of the I-55 corridor. Despite plenty of sunshine
by afternoon...highs today will mainly be around 60 degrees due
to the deep low level northeast flow.


Long term...(tonight through saturday)
issued at 330 am CDT sun Apr 26 2015

Fairly quiet weather on tap across the forecast area much of the
week. Persistent northeast flow to keep dry conditions in place...
with high temperatures rising a couple degrees each day until we
finally get near or just above normal by the end of the work week.

Upper low currently in the process of closing off over western
Arizona...and this will be tracking across the southern U.S. Over
the next few days. All of the models keep the associated moisture
south of the Ohio Valley. A shortwave will also be tracking along
the Canadian border...and as previous model runs indicated, a small
closed low will pinch off in the southern part of the wave. The
European model (ecmwf) and Canadian models have this small low dropping across
Minnesota and Iowa Tuesday night...while the tail end of the NAM
brings this into northern Illinois and the GFS progresses the wave
well east before the low can form. Net result of all of this is for
dry conditions middle week.

As we get later in the week...upper ridging will build northeast
across the plains into Manitoba...while general broad troughing
continues across the eastern U.S. This ridge flattens by Friday as
the northern stream becomes more active along the Canadian border.
Both the GFS and European model (ecmwf) bring a surface boundary through the area
Friday night and Saturday...with some light precipitation. The
solutions begin to diverge by the GFS brings a stronger
upper wave and surface front through Saturday night with showers and
thunderstorms...although the European model (ecmwf) does hint at potential mesoscale convective system
activity as well. With the more divergent solutions...have kept the
late weekend forecast dry for now.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1100 PM CDT Sat Apr 25 2015

MVFR and occasional IFR ceilings will be replaced by VFR conditions
from north to south over the next 2 to 4 hours as high pressure
settles over the region. Latest surface observations and
satellite data suggest the back edge of the MVFR ceilings was located
from just north of Rantoul and Bloomington...northwest to near
Galesburg. The current movement should push the lower clouds to
the south of the taf sites by 09z...with VFR conditions expected
to prevail for the remainder of the forecast period. Surface winds
will remain out of the northeast at 12 to 17 kts with occasional
gusts around 23 kts...with the winds diminishing to 8 to 15 kts by
dawn...before picking up again from a northeast direction on
Sunday with speeds in the 10 to 15 knots range...with gusts around 20
kts at times...especially from late morning through about 22z. Winds
will diminish rapidly by 00z.


Ilx watches/warnings/advisories...


Short term...Miller
long term...geelhart

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