Area Forecast Discussion
Issued by NWS Central Illinois

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
430
FXUS63 KILX 041755
AFDILX

AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1155 AM CST THU FEB 4 2016

.UPDATE...
ISSUED AT 1044 AM CST THU FEB 4 2016

Forecast generally on track today and only needed to adjust the
sky cover a bit today. By late morning most of CWA is enjoying
ample sunshine, expect for some lingering scattered/broken 3k ft
clouds east of I-57 and some ceilings near the Indiana border.
Another area of clouds from 6-10k ft was over IA and tracking
toward nw IL/MS river. 1035 mb high pressure over central Texas
was ridging into the mid MS river valley/sw IL. Aloft an upper
level trof will remain over IL today and then shift east of IL
by overnight. An embedded weak northern stream short wave over IA
will track into the IL river valley later this afternoon and
increase VFR clouds into mainly northern half of CWA from I-72
north during this afternoon as sunny skies become partly to mostly
cloudy over IL river valley during afternoon. Seasonable highs
this afternoon in the mid to upper 30s (mildest readings sw CWA)
with west winds of 8-16 mph and few gusts to 20 mph, and winds
veering more sw during the afternoon.

&&

.SHORT TERM...(Today)
ISSUED AT 230 AM CST THU FEB 4 2016

High pressure advancing into Illinois from the west will push the
remainder of the low clouds into Indiana shortly after sunrise. A
low pressure system approaching Wisconsin today will drag a band of
clouds into northern Illinois this afternoon. The clouds may affect
our counties north of Lincoln, but overall coverage should not
become overcast at any point. In general, most of our forecast area
should see enough sunshine today to help high temperatures climb to
around normal readings. Afternoon highs should range from the mid
30s in our northeast counties towards Danville, to the upper 30s in
the southwest around Jacksonville.

As the high pressure center edges closer to IL, the pressure
gradient will continue to diminish, helping to curtail the wind
gusts, which will be a nice change from yesterday`s blustery
conditions. By mid-morning, we expect winds to steady out in the 8
to 12 mph range and remain there through the day. Wind direction
will shift from W-NW this morning to W-SW this afternoon as the
surface ridge axis passes across IL.

.LONG TERM...(Tonight through Wednesday)
ISSUED AT 230 AM CST THU FEB 4 2016

Broad upper trough covers a large part of the central U.S. this
morning, and will approach the East Coast on Friday. Second trough
currently evident along the Pacific coast of British Columbia will
dig this evening as it crosses the Rockies, and should be centered
over the Mississippi Valley by Saturday morning. Main energy with
this second trough will be closer to the Great Lakes, so the
forecast will be kept dry to start the weekend. A nice warm-up on
tap as the upper trough passes, and highs both Saturday and Sunday
should be well into the 40s, with perhaps some 50 degree readings
south of I-70.

Main story in this part of the forecast remains with the cold
weather slated for early next week. GFS and ECMWF are coming into
better agreement with a large closed upper low forming over the
upper Mississippi Valley early next week, settling into southern
Ohio by Tuesday morning. Cold air of around -17C at 850 mb will be
drawn southward behind the low all the way down into the Tennessee
Valley. Extent of the cold temperatures will be dependent on any
snow cover that may form, which is feasible as persistent snow
showers will rotate southeast from the associated surface low near
the Great Lakes Monday and Monday night. Even without the snow,
temperatures likely to fall into the single digits Tuesday night
over most of the CWA, with highs struggling to reach the 20s on
Tuesday and Wednesday.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1155 AM CST THU FEB 4 2016

VFR conditions expected to continue across the central IL airports
nexts 24 hours through 18z/noon Fri. A weak short wave trof over
IA will pivot east across central/northern IL later this afternoon
and bring broken 5-9k ft from IA into central IL. Have these
clouds arriving at PIA 20-21Z and CMI by 23-24Z. These clouds to
scattered out late tonight or early Fri morning. The MVFR
ceilings and chances of flurries appear to stay north of I-74
over northern/NE IL overnight. A weak cold front to move se over
central IL between 08-12Z. West winds 6-11 kts veer sw this
afternoon and then WNW behind weak front late tonight into Fri
morning.

&&

.ILX Watches/Warnings/Advisories...
NONE.

&&

$$

UPDATE...07
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...07



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.