458
FXUS63 KDVN 021112
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
612 AM CDT Tue Jun 2 2026

.KEY MESSAGES...

- Quiet stretch of weather through midweek, owing to surface
  high pressure over the Great Lakes Region. Mostly clear skies,
  temperatures in the 80s, and light winds will result through
  Wednesday.

- Blocking pattern breaks down Thursday/Friday, with warm
  advection resulting in temperatures and humidity trending up
  as we head towards the weekend. Above normal temperatures and
  moisture will be in place.

- Near daily chances for storms will be seen Friday onward. Too
  soon to determine a severe threat, but a few stronger storms
  and localized heavy rainfall cannot be ruled out Friday
  through Sunday.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 150 AM CDT Tue Jun 2 2026

Surface high pressure settles over the Great Lakes Region through
Wednesday, bringing a stretch of quiet weather. Weak llvl easterly
flow will continue to keep dry air in place. Today, we will see
another beautiful day throughout the area. Mostly clear skies will
remain, with temperatures in the low-mid 80s. Clear skies and light
winds tonight will allow temperatures to drop quite a bit again,
with temperatures in the low-mid 50s. Thus, a beautiful night is
ahead of us, perfect for opening up some windows!

Going into Wednesday, the deep upper ridge starts to flatten over
the Upper Mississippi River Valley, helping to push the surface high
easterly through the day. This will result in a more southerly
component in the llvl winds, especially late Wednesday into
Thursday. Wednesday will pretty much be a similar day to Tuesday,
with mostly clear skies and temperatures in the low-mid 80s.
Although, the increasing southerly flow will set the stage for
warmer weather in the coming days, with increasing humidity.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Issued at 150 AM CDT Tue Jun 2 2026

Thursday-Saturday...The trough that has been stalled out over the
Northern Rockies finally moves into the Northern Plains and south-
central Canada, kicking the ridge over the Great Lakes southeastward
and pulling a shortwave in the subtropical jet northeastward into
the Central Plains. Low pressure will deepen along the Front Range
and near the North Dakota-Canada border as our winds shift out of
the south, advecting in warmer, moist air from the Gulf. We will see
the best moisture work into the area Friday into Saturday, where
guidance brings PWATs as high as 1.50-1.75" into the area. Thus,
quite a bit of moisture will be present, making it feel humid late
week into the weekend. As a cold front progresses across the
Northern Plains and bands of shear vorticity are advected into Upper
Mississippi River Valley, rain chances increase to 40-60% Friday
into Saturday. There is uncertainty on the precipitation amounts
through Saturday, with guidance suggesting a range from a few
hundredths to half an inch. Given such high PWATs in place (nearing
the 90-99th percentile of climatology), any storm will have the
potential to drop efficient and heavy rainfall, even if brief. With
increasing moisture, cloud cover and convective debris will lead to
some uncertainty on high temperatures. These conditions can keep
temperatures in the low-mid 80s going into the weekend, but there
will be the potential for upper 80s to near 90 if cloud cover is not
as robust. Either way, increasing humidity will make it feel quite
unpleasant out there, especially Saturday. Overnight temperatures
will also remain above seasonal norms, owing to increasing dewpoints.

In terms of severe weather during that timeframe, current GEFS
ensembles has a 40-60% chance of SBCAPE values exceeding 1000
J/kg, but the displaced trough to the north should limit the
surface to 500mb effective bulk shear to only 25-30 knots. While
this isn`t the most favorable environment for severe storms,
organized convection will be possible where a stronger storm
cannot be ruled out.

Sunday...Another shortwave in the subtropical jet stream is pulled
northeastward into the Central Plains by a longwave trough digging
into the western CONUS. Since the last forecast package, a deepening
ridge over the Central CONUS looks to keep that system shunted south
and away from our area. The EURO suite continues to keep
precipitation chances over the area, but there is uncertainty
amongst long range guidance. NBM guidance continues to hold onto
Slight-Chance PoPs, especially in the afternoon hours, where
diurnally driven convection is possible.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 601 AM CDT Tue Jun 2 2026

VFR conditions will prevail through the TAF period, with light
easterly winds increasing to around 10 KTs by 18z. Otherwise,
passing high clouds will be seen through the day, with no sig
wx expected at this time.

&&

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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Delaune/Gunkel
AVIATION...Gunkel