357
FXUS63 KILX 011743
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1243 PM CDT Sat Jun 1 2024

.KEY MESSAGES...

- Weak instability associated with a slow-moving low pressure
  system is bringing some showers and thunderstorms (80-100%
  chance) through central Illinois this morning, lasting into late
  afternoon. Severe weather is not expected.

- After a dry Sunday, there are several more chances for rain are
  in the forecast through late Wednesday. A threat of severe
  weather returns for Tuesday.

&&

.UPDATE...
Issued at 1020 AM CDT Sat Jun 1 2024

Water vapor imagery denotes an upper shortwave centered over the
middle Mississippi Valley as of mid morning. Persistent rain showers
are ongoing over eastern Illinois with more scattered showers in
western parts of the state. Activity should become more periodic
by this afternoon as the upper wave slowly approaches Indiana.
Weak instability of a few hundred J/kg will develop by this
afternoon and could result in an isolated thunderstorm through
early evening. Precipitation and cloud cover will prevent
temperatures from climbing no more than just a few degrees higher
than where they are now, with values looking to max out in the
upper 60s to low 70s for today.

NMA

&&

.DISCUSSION...
Issued at 230 AM CDT Sat Jun 1 2024

Happy meteorological summer, readers! Today, showers and
thunderstorms are expected to slowly travel northeast across the
CWA. Currently, the environment is pretty dry, as seen in our 00z
sounding last night. The moist air with the system will have to eat
away at the dry air before the showers become more widespread. By
the afternoon, there looks to be a few hundred J/kg of CAPE,
supporting some thunderstorms. However, they aren`t expected to be
severe. After 18z the showers and thunderstorms will be come more
scattered than widespread. By early evening, the precipitation
should be mainly out of the area, with some lingering isolated
showers remaining. QPF for today`s round of rain ranges from 0.5-1
inch. Areas near and south of I-70 have a 30-50% chance of getting
more than an inch of rainfall.

There is a brief ridging period over the Midwest Sunday, then a
short wave and a cold front are set to move through starting Monday.
Sunday morning could be a big foggy for some portions of central/SE
Illinois with clear skies, calm winds, moist grounds, and a high
pressure setting up. Monday into Tuesday, the showers should be
mostly scattered as a short wave passes overhead. However, there is
an increasing threat (albeit low chance, as of now) for severe
weather Tuesday as Wednesday`s cold front begins to approach from
the west. Wednesday`s round of showers/t`storms will be more
widespread across central Illinois and will be associated with a
cold frontal passage. Come Thursday, the forecast looks to be dry
for the weekend.

Temperatures will warm back up into the mid 80s tomorrow, lasting
through the extended. Highs won`t cool slightly (mid 70s to low 80s)
until the cold front passes on Wednesday night/Thursday morning.
Lows will mainly range from upper 50s to low 60s through the 7 day
period.

Copple

&&

.AVIATION...  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jun 1 2024

Low pressure is over west central Illinois late this morning and
will lift to the Great Lakes overnight. Showers and a few isolated
embedded storms along with IFR ceilings will continue ahead of
the low, but precip should begin to taper off from the west
through the evening hours. High pressure builds into the west late
tonight into Sunday morning. The combination of recent rainfall
with light and variable winds under the ridge axis may allow fog
or low stratus to develop overnight or redevelop in the case of
stratus.

Deubelbeiss

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$