494
FXUS63 KDVN 290601 CCA
AFDDVN

Area Forecast Discussion...CORRECTED
National Weather Service Quad Cities IA IL
101 AM CDT Thu Oct 29 2026

.KEY MESSAGES...

- A cold front brings slightly cooler, drier air to the area today
  before rain chances return Friday into Saturday.

- A more active weather pattern could develop early next week,
  bringing more rain and breezy conditions.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 1253 AM CDT Thu Oct 29 2026

A cold front moves through the area today with some lingering
rain showers and isolated storms, mainly east of the Mississippi
River. Northeasterly flow will advect in slightly cooler, drier
air into the CWA with highs in the mid-60s to low 70s. By
tonight, the mid- level remnants of Vance in the East Pacific
lifts northeastward into the Southern Plains. While the surface
response will be weak, pressure falls across the Central Plains
on Friday and southwesterly flow aloft ahead of Vance`s remnants
could drag a warm front northward towards the Highway 34
corridor. Isentropic upgliding and WAA to the north of this
boundary are likely to support widespread rain showers (70-90%
coverage) with embedded thunderstorms across the CWA Friday
afternoon into Friday night. Latest NBM guidance favors rainfall
amounts between 0.25-0.75 inches (50-70% chance) with this
round, but a swath of 1+ inches cannot be ruled out, especially
north of Highway 34.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 1253 AM CDT Thu Oct 29 2026

Saturday-Sunday...The warm front near the Highway 34 corridor
finally moves further north into the CWA, spawning a smaller
round of isolated showers and storms (20-30% coverage) on
Saturday. As the boundary becomes diffuse Saturday night, dry
conditions return as southeasterly flow advects in more mild air
for Sunday. Attention turns west though as a longwave trough
propagates eastward into the Rockies, setting the stage for a
potentially active start to the work week.

Monday-Wednesday...As the longwave trough shifts eastward into
the Plains, there are two potential scenarios:

Scenario 1 (70% chance per LREF cluster analysis): The troughs
in the polar jet and subtropical jet become out of phase,
leading to a slower, closed-heights center over the south-
central Plains and a fast northern trough. This would support
two low pressure centers: one over the Great Lakes and east-
central Canada and another across the Southern Plains and Lower
Mississippi River Valley. With a split system, rainfall amounts
are likely to be lower.

Scenario 2 (30% chance per LREF cluster analysis): The troughs
stay in phase, deepening a singular mid-latitude cyclone over
the Central Plains that would move into the Mid-Mississippi
River Valley. This solution would favor more rainfall and
windier conditions for our CWA.

Regardless of scenario though, precipitation chances and winds
are forecasted to increase heading into Monday night and stick
around into Wednesday. With the background cyclonic flow aloft,
there could be multiple rounds of rainfall over this time
period. Once the mid-latitude cyclone or an associated cold
front moves through or east of the CWA, northerly flow should
set in and advect in some cooler, more seasonable air by the
middle to end of next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1253 AM CDT Thu Oct 29 2026

A mix of VFR and MVFR conditions is likely through 17 UTC at
all TAF sites. An approaching cold front is currently supporting
40 knots of LLWS around 2 kft and producing scattered showers
and thunderstorms across eastern Iowa. These showers and storms
have already impacted CID and DBQ, and there is a small chance
(30%) of a few showers reaching MLI between 07 UTC and 10 UTC.
After the front reaches each TAF site, the LLWS will dissipate
as winds shift from southerly to northerly. A narrow cloud band
of MVFR ceilings (1.5 to 3 kft) is likely to form in the wake of
the front and move through all the TAF sites for a few hours
this morning. Once this band passes, skies clear out as VFR
conditions return for the remainder of the period.

&&

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

&&

$$

SHORT TERM...Delaune
LONG TERM...Delaune
AVIATION...Delaune