Area Forecast Discussion
Issued by NWS Central Illinois
FXUS63 KILX 021157
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
657 AM CDT FRI OCT 2 2015
ISSUED AT 330 AM CDT FRI OCT 2 2015
Another day of below normal temperatures and gusty northeasterly
winds is anticipated today across central and southeast Illinois. A
blocky upper level flow pattern persists across North America,
keeping area in a tight surface pressure gradient between high
pressure centered over eastern Canada and the low pressure
associated with Hurricane Joaquin. This surface pattern is helping
to keep a flow of cool/dry air in place. However, an upper level
disturbance is spinning across northern Mississippi & Alabama.
Deeper moisture wrapping around this feature is spreading clouds
into east-central and southeast Illinois early this morning, and
some westward expansion is expected today. In addition, a few
sprinkles or light showers may spread into southeast Illinois by
late today, but expect most locations to stay dry.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 330 AM CDT FRI OCT 2 2015
Category 4 Hurricane Joaquin with 130 mph winds still impacting
the central Bahamas. The 00Z GFS has trended toward the ECMWF model
with further east track of Hurricane Joaquin keeping it well off the
Atlantic coast as it tracks northward through this weekend. National
Hurricane Center official track is also trending toward further east
track which ECMWF model has been showing past few runs.
Strong upper level trof digging southward into the TN river valley
and and central/eastern Gulf coast states with a 569 dm 500 mb low
over AL. This deep trof to steer hurricane on northward journey and
likely keep it off shore. NAM and GEM models still bring hurricane
onshore toward Carolina coast by Sunday morning, but these model
solutions were not followed. IL will be on western fringe of its
cloud cover and light rain showers to affect eastern IL at times
through early Sunday morning. Have 20-30% pops in southeast IL
tonight and along and southeast of a Danville to Flora line on
Saturday. Isolated showers mainly from I-57 east on Saturday night
and lingering isolated shower possible early Sunday morning near
Danville. More clouds over eastern IL to keep these areas a bit
cooler during day and a bit milder at night through this weekend.
Breezy ne winds to continue through Saturday especially during
daytime hours with gusts 20-30 mph and then begin to weaken on
Sunday. Lows tonight range from low to mid 40s over IL river valley
to upper 40s to near 50F over eastern IL. Highs Sat in lower 60s
eastern IL and mid to upper 60s western IL.
Temps to start to modify early next week with highs in the mid 60s
to lower 70s Sunday (mildest in southeast IL) and 70-75F on Monday.
Weak surface high pressure settles into IL early next week and
diminishes winds and returns more sunshine and start of a warming
trends. Highs to reach the upper 70s to near 80F by middle of next
week. 00Z models have trended slower with approach of cold front and
now it appears dry over area through at least Wed evening with upper
level ridging into IL by Wed. Have slight chances of showers
overnight Wed night nw of IL river and then have 20-40% chances of
showers over area Thu/Fri with lowest pops in southeast IL.
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 651 AM CDT FRI OCT 2 2015
Predominantly VFR conditions expected across the central Illinois
terminals through the 12Z TAF valid time. However, there is a
patch of MVFR low clouds than will impact a few of the terminals
early this morning. Otherwise, northeast winds will prevail
through the period, with gusts over 20 kts for much of the
daytime hours today.