056
FXUS63 KDVN 300511
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1211 AM CDT Thu Jul 30 2026

.KEY MESSAGES...

- Seasonable temperatures, dry conditions, and some hazy skies Thursday.

- Widespread showers and thunderstorms likely Friday. There is a
  70-80% chance of rainfall amounts over 1". No severe weather
  is expected.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 205 PM CDT Wed Jul 29 2026

Seasonable temperatures and dry conditions were seen today, as
high pressure dropped south over southeast WI and the Great
Lakes. Dewpoints are also 4 to 10 degrees lower compared to
24hrs ago, making it feel more tolerable outside. Visible
satellite shows a Cu field across central and northeast IA, with
recent trends showing smoke aloft beginning to thin over the
CWA.

Quiet conditions will continue through the evening/overnight
hours, as surface high pushes south over northern IL. As winds
go calm, some shallow fog is possible in the Rock river valley
tonight. Overnight lows to drop into the lower 60s.

Thursday...a rinse and repeat forecast is expected with mostly
sunny skies, some haze from upstream wildfires, and similar
afternoon highs to today reaching the mid to upper 80s. Despite
deep mixing, forecast soundings show a dry column and very weak
winds through 500mb leading to a persistence forecast.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 205 PM CDT Wed Jul 29 2026

Thursday Night through Friday...a shortwave currently over southwest
UT, will round the edge of the upper ridge and move over the
northern Plains/Midwest as a positively tilted shortwave
bringing rain chances to the region. A strong LLJ coupled with
increasing low level moisture will allow scattered showers and
thunderstorms to develop across western and central IA nearing
our CWA border by 12z Friday. Forecast soundings and moisture
transport vectors keep the deeper moisture over central IA prior
to 12z Friday and thus the onset of rain may be delayed
slightly. Large scale forcing will increase through the day
Friday and with deep warm cloud depths (4500m) and PWs rising
over 2", efficient rain processes to allow for widespread
showers. With MUCAPE values between 600-1000 J/Kg and marginal
mid level lapse rates across the southern half of the CWA, can`t
rule out some embedded thunderstorms but overall coverage
should be quite limited leading to lower but steady rainfall
rates. Available instability will be the limiting factor to
organized convection Friday. New model guidance continues to
show different surface low tracks as noted in last night`s
forecast discussion. A northerly track still shown by the ECMWF,
would favor highest QPF totals over the northern third whereas
the NAM/GFS/RRFS solutions show a southerly track over southern
IA into eastern MO favoring 2+" totals over the Hwy 30 to I-80
corridor. The WPC/NBM forecast currently favors the northerly
track, but further refinements in the heaviest axis is likely in
the next 24-36 hours. Regardless, 24-hr rainfall totals over 1"
is becoming more likely for much of the CWA with NBM
probabilities now over 70% area-wide! A good soaking rain will
be very welcome and will also keep us cooler Friday, with highs
only in the 70s.

Saturday...any lingering showers to move and exit to the southeast
by mid-day. A tight pressure gradient behind the departing system to
bring a period of gusty northerly winds up to 30 mph and
combined with wrap around clouds will make it feel more like
late August. Afternoon highs to top out in the 70s, coolest east
of the MS RVR.

Sunday through Wednesday...dry conditions and seasonable
temperatures are forecast to start the new week, as an upper ridge
moves into the upper Midwest behind our departing system
tracking over the Ohio river valley. Active storm track to
remain over the northern Plains and southern Canada. Model
ensembles show a transition to a zonal flow aloft mid to late
week, leading to warmer temperatures and additional rain
chances.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1208 AM CDT Thu Jul 30 2026

VFR conditions are expected through the TAF period. High pressure over
northern Illinois will keep winds light and south-southeasterly through
30/16Z, after which winds will strengthen to 10-12 kts as the high
shifts southeastward. High cirrus will move in after 30/12Z and
increase in coverage after 30/21Z ahead of an incoming
disturbance.

&&

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

&&

$$

SHORT TERM...Gross
LONG TERM...Gross
AVIATION...Ellingworth