709
FXUS63 KDVN 071107
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
607 AM CDT Sun Jun 7 2026

...Updated for 12z Aviation...

.KEY MESSAGES...

- Rounds of nocturnal and diurnal convection through Monday
  night will bring a risk of locally heavy rainfall due to weak
  winds aloft. If the heavy rain occurs in an urban area,
  localized flash flooding is possible.

- Heat and humidity will return around mid-week with
  temperatures in the 90s and heat indices pushing 100 or
  higher. The probability of heat headlines around mid-week is
  33-40 percent.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 207 AM CDT Sun Jun 7 2026

A lake/convection induced boundary has pushed into the area with it
running roughly from KMIW, to just north of the QCA metro area and
then to between KC75 and KPIA. With little in the way of forcing
across the area, only a brief rogue shower or storm is possible
through sunrise.

After sunrise, said boundary will become the focus for new
convection. Here the very short term models differ on timing but
generally agree that the boundary will be the initiation point. The
timing difference is traceable to the arrival of a weak upper level
disturbance from the Plains. Thus through mid-morning mainly dry
conditions will be seen with diurnal convection occurring anytime
from late morning on.

Away from the boundary, areal coverage of the convection looks to be
20-40 percent. Along the boundary a broken line of storms will
develop that slowly moves north through the afternoon. Outflow
boundaries from the convection will then be the foci for more
convection late this afternoon and evening.

After sunset areal coverage will slowly increase as the LLJ
develops. The highest coverage looks to be west of the Mississippi.
Toward sunrise Monday the highest coverage will slowly shift along
the Mississippi River.

Monday isolated to scattered convection will be seen west of the
Mississippi with the higher coverage along/east of the Mississippi.
A weak front arriving from the Plains will bring the convection to
an end from west to east late Monday afternoon and night.

Due to weak winds aloft, no severe storms are anticipated today or
Monday. However, the weak winds aloft means slow moving storms that
will be capable of producing locally heavy rainfall. If that heavy
rain occurs over an urban area, localized flash flooding is
possible.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 207 AM CDT Sun Jun 7 2026

Tuesday through Sunday
Assessment...high (>80%) confidence of temperatures well above
normal. Low (20-25%) confidence for rain.

Trends with the models continue to show temperatures well above
normal for much of the week.

However, the highest heat indices now look to occur in the
Tuesday/Wednesday time frame. A seasonably strong front arriving
Wednesday night will bring cooler temperatures on Thursday with
temperatures moving to near normal for next weekend.

Heat indices Tuesday continue to indicate 95 to 100 but areas south
of I-80 have a 30-40% probability of exceeding 100. On Wednesday the
probability of seeing heat indices of 100+ is now at 50-60%.
Depending upon how rain chances play out, heat headlines may be
needed in the Tuesday/Wednesday time frame.

The model consensus indicates the daylight hours of Tuesday are dry.
Tuesday night into Wednesday is a question. A weak signal has
started to develop suggesting a nocturnal storm complex running
around the edge of the heat dome. If this occurs it would play
significantly into the need for potential heat headlines Wednesday.

Albeit a weak signal, some of the ensemble members of the various
models are pointing to rain and have a 20-30 percent chance for rain
Tuesday night into Wednesday.

Wednesday night into Thursday looks interesting.

A much stronger front is progged to move through the area that will
be associated with a strong upper level disturbance. Winds in the
mid-levels of the atmosphere are progged to be around 50 knots
indicating organized storms with the potential for severe storms.
CSU ML progs and other ML analog sites from the June 6th model runs
have a 15-30% probability of severe storms occurring. Thus the
transition from hot and humid conditions may have severe storms.

Thus Wednesday night has the best chances for rain. The current
model consensus has 50-70 percent chances for rain. Outside of
Wednesday night, the model consensus has daily 20-35 percent chances
for rain Thursday through Sunday.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 600 AM CDT Sun Jun 7 2026

An approaching upper level disturbance and copious amounts of
moisture will set the stage for periodic showers and some
storms through the TAF cycle, with the main challenge of timing
and locations of potential greatest impacts from convection
(IFR potential for visibility and localized gusty winds 25-35+ kt
possible). Otherwise, predominantly rounds of showers and
bouts of MVFR conditions (mainly visibility but some pockets of
lower ceilings possible). Looks like the thunder potential will
be largely concentrated in the afternoon and evening. Outside
of the precipitation, predominantly VFR conditions are expected.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...08
LONG TERM...08
AVIATION...McClure