Area Forecast Discussion
Issued by NWS Central Illinois
FXUS63 KILX 281727
Area Forecast Discussion
National Weather Service Lincoln IL
1227 PM CDT Mon Jul 28 2014
ISSUED 1040 AM CDT Mon Jul 28 2014
Mostly sunny and cool conditions prevail across central Illinois
this morning. Thanks to cyclonic flow aloft and 500mb temps of
around -11 to -12C, a good deal of diurnal Cu is expected to
develop. NAM Cu-rule suggests the greatest coverage will likely be
across east-central and southeast Illinois and the latest visible
satellite imagery supports this. Current forecast features mostly
sunny skies across much of the KILX CWA, with partly sunny
conditions along/south of I-70. Think this still looks good, so am
not planning any forecast updates at this time.
ISSUED 1227 PM CDT Mon Jul 28 2014
VFR conditions will prevail through the entire 18z TAF period.
Latest visible satellite imagery shows mainly scattered diurnal
clouds across central Illinois: however, a more concentrated area
is noted east of a KBMI to KDEC line. As a result have included a
2-hour TEMPO group for MVFR ceilings at KCMI early this afternoon.
Clouds will rapidly dissipate toward sunset, with clear skies
expected overnight. Brisk N/NW winds will continue through the
afternoon hours, with occasional gusts to around 20kt. Atmosphere
will decouple after sunset, resulting in light/variable winds
overnight. After that, NW winds of around 10kt will resume Tuesday
ISSUED 257 AM CDT Mon Jul 28 2014
High pressure slowly building into the Midwest behind the exiting
storm system making its way into the Northeast today. Northerly
winds today and a bit breezy, though less so than yesterday.
Cooler high temperatures after a cool start this morning...highs
well below normal. Main issues for the forecast are few as the
atmosphere sets up into a northwesterly flow pattern for the
remainder of the week. Temperatures with northwesterly flow aloft
dependent on the location of the ridge axis...slowly moderating as
the northerly flow lightens...and temps get more of an influence
from the sunshine. That being said...not much of a change through
the week overall and max temps remain below normal through the
forecast. With the trof parking over the eastern half of the
country and northwesterly/some cyclonic curve to the flow aloft,
chances will begin to increase for some instability showers
towards the end of the week.
SHORT TERM...Today and tomorrow...
Cooler and breezy with northerly winds ushering in temperatures
well below normal. Time heights showing some low level moisture
and cu rule putting a substantial cu deck over much of the FA,
further inhibiting any warm up. Tonight, still quiet, clearing and
cooler with overnight lows dropping into the 50s. Tomorrow is
almost a simple rerun of today with the temperatures just a couple
degrees higher and the winds more northwesterly. Models are
beginning to show some afternoon showers to the northeast...and
have kept some slight pops in...though coverage is expected to be
LONG TERM...Wednesday through Sunday...
Continued below normal temps and northwesterly flow with some
small impulses possibly diving into the trof over the eastern
CONUS. Between the short waves and diurnally driven instability
showers, pops start to show up particularly for the afternoon and
early evening hours. Models continue to enhance this activity on
Thursday night and into Friday as the impulses start moving into
the west coast and trying to break down the ridging to the west.
Models beginning to signal the progression of the deep trof out of
the region for late Sunday and into Monday...which would mean a
return to warmer conditions.