171
FXUS63 KDVN 111057
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
557 AM CDT Sat Jul 11 2026

...Updated for 12z Aviation...

.KEY MESSAGES...

- Slightly above normal temperatures for mid July are forecast
  through the period with gradually warming of high temperatures
  into the mid 90s by Wednesday/Thursday of next week. Limited
  humidity with dewpoints in the 60s will keep heat indices
  below 100 through the period.

- The forecast is large dry through the period with low chances
  of precipitation late next week.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 1247 AM CDT Sat Jul 11 2026

A MCV and 500 MB trough continue to slowly exit southeastward
into Illinois with precipitation coming to an end in far
southeast Iowa, northeast Missouri and west central Illinois by
12 UTC.

In the wake of this system, high pressure is forecast to build
into the region at the surface and aloft bringing quiet weather
to the area through the weekend. Winds will be east to
northeasterly through the period with speeds of 5 to 10 knots
through the day then becoming light overnight. These winds will
draw lower dewpoints in the lower to mid 60s into the area.
Temperatures will be warm in the mid to upper 80s. Sunday is
forecast to be 1 to 2 degrees warmer than today.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 1247 AM CDT Sat Jul 11 2026

Deterministic and Ensembles are in good agreement in building
ridging at the surface and aloft across the Plains Sunday night
through midweek. A closed low in the Ohio and Tennessee Valleys
and a closed 500 MB 600 DM contour in the northern Plains form a
Rex Block across the central US through the middle of next
week. The position of the high through Wednesday would keep
dewpoints in the 60s through midweek. Temperatures will
gradually modify through the week with high temperatures in the
upper 80s to lower 90s and low temperatures warming from the mid
60s to the lower 70s after Wednesday. Dewpoints in the 60s will
limit heat indices to the mid to upper 90s next week.

Beyond Wednesday, models begin to disagree as the GFS shifts the
high pressure to the east of the area while other models and the
GFS Ensemble Mean retrograde the Rex Block to the west. This is
bringing low chances of showers to the area Thursday and Friday
for different reasons. The operational GFS solution allows for
a storm system to approach the area from the west while the
retrograde of the Rex Block brings the storm track closer to the
area allowing a shortwave digging into the eastern Great Lakes
to bring a cold front into the area and produce light chances of
showers ands storms. The retrograding Rex Block solution
appears to be favored by models and the NBM and think that this
is the more likely scenario given the tendencies for blocking to
retrograde with time.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 555 AM CDT Sat Jul 11 2026

VFR conditions expected through the TAF period. Patchy MVFR fog
can`t be totally ruled out at the start of the period and again
late tonight, but this potential at the TAF sites looks quite
low and non-mentionable with HREF and NBM probabilities for
visibility <5SM at less than 20%. Soundings show northeast winds
should increase to around 10 to 15 kt by mid morning through
afternoon, with winds then becoming light and variable tonight.

&&

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

&&

$$

SHORT TERM...Cousins
LONG TERM...Cousins
AVIATION...McClure