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
FXUS63 KILX 170752

Area Forecast Discussion
National Weather Service Lincoln IL
252 AM CDT MON OCT 17 2016

.SHORT TERM...(Today and tonight)
ISSUED AT 251 AM CDT Mon Oct 17 2016

Another unseasonably warm night across central Illinois thanks to a
gusty southerly breeze helping to keep early morning temperatures
in the upper 60s to lower 70s. The main synoptic scale warm front
has shifted to our north early this morning and will continue to
push away from our area today as strong low pressure tracks
northeast out of Kansas into the upper Great Lakes by later
today. Main forecast concerns today include high temperatures
this afternoon and how many records will fall along with the
potential for some wind headlines over parts of the area
mainly for the early afternoon thru about 00z/7pm.

Guidance numbers over the past few days have been coming up short
with respect to our afternoon temperatures and a few of those
values for today seem a bit conservative, especially with the
gusty south to southwest winds this afternoon and 850 mb temps of
around +20C. This type of pattern usually leads to our warmest
temperatures and have leaned on the warmest guidance which would
suggest highs ranging from the middle 80s far northeast to around 90
in west central and far southwest IL. If these temperatures are
realized this afternoon, several sites will break records for
October 17th. See the climate section below for a list of the
cities and their record highs for today. As far as the winds are
concerned, based on the forecast soundings for this afternoon, we
should be able to easily mix down from around 875 mb with 45-50 kt
winds located near the capping inversion just above that. Winds
generally in the 925-875 layer range from 30-35 kts this afternoon
which leads to sustained winds of 20-25 mph with gusts possibly as
high as 40 mph at times, which is just below wind advisory

The gusty south winds will diminish some tonight as the stronger
core of winds in the 925-850 mb layer shifts off to our east and
south overnight. However, another very mild night is in store for
the forecast area as southerly winds should hold up enough to keep
overnight lows in the mid to upper 60s, about 20 to 25 degrees above
where they should be for the middle of October.


.LONG TERM...(Tuesday through Sunday)
ISSUED AT 251 AM CDT Mon Oct 17 2016

Warmer air mass starts to get shoved southward on Tuesday as a cold
front moves toward the Ohio Valley. Forecast soundings initially
only showing a small pinch of moisture as the front passes, and will
limit any PoP`s on Tuesday to around 20% over east central Illinois.
However, the front will stall out as it becomes parallel to the
upper flow. Evening model suite generally as this across southern
Missouri and into southern Illinois between I-64 and the Ohio River
by evening, with a surge back northward as a wave of low pressure
rides northeast along the front. The latest GFS and ECMWF have this
low as far north as I-70 by Thursday evening, while the NAM keeps
the low all the way in southern Tennessee. With a more northern
surge favored, PoP`s will increase over most of the forecast area on
Wednesday, with a few thunderstorms possible Wednesday and Wednesday
night over the southeast third of the CWA. Far northwest corner near
Galesburg may get away with any additional rain as most of the
models favor a sharper northern edge of the rain shield, although
the ECMWF solution is more diffuse with the approach of the upper

Still some model disagreement on the aforementioned upper wave, with
the ECMWF on the more progressive side and the GFS deeper and slower
late this week. Both favor a building ridge over the Rockies and a
fast northwest flow. Friday appears to be the coolest day of the
week with most highs around 60, but temperatures moderate again this
weekend as the ridge starts to shift eastward.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1150 PM CDT Sun Oct 16 2016

VFR conditions will prevail at all TAF sites next 24hrs. High
cirrus continues to spread over the area tonight, but short range
models continue to also show some low clouds around 4kft advecting
over the TAF sites, beginning in the west in a few hours and then
slowly progressing to the east, reaching the DEC and CMI TAFs late
tonight. The clouds are forecast to last several hours and then
become scattered with high cirrus still present over the area. DEC
and CMI will see the lower clouds longer, into the late morning
hours. Skies are expected to clear by evening hours. Winds will
remain southerly through the period with some breezy conditions to
start with, but then decreasing some when the lower clouds arrive.
Gusty winds will return during the morning hours and then increase
some during the afternoon. Winds will decrease some during the
evening, but still remaining breezy/gusty.


Issued at 250 AM CDT Mon Oct 17 2016

Record highs for today:

Charleston....... 88 (1950)
Decatur.......... 89 (1950)
Effingham........ 85 (1965)
Galesburg........ 87 (1950)
Jacksonville..... 89 (1964)
Lawrenceville.... 85 (1963)
Lincoln.......... 87 (1935)
Normal........... 86 (1938)
Peoria........... 86 (1950)
Springfield...... 86 (1964)
Urbana........... 87 (1950)


.ILX Watches/Warnings/Advisories...


LONG TERM...Geelhart
CLIMATE...Geelhart is the U.S. government's official web portal to all federal, state and local government web resources and services.