Marion, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

347
FXUS63 KDVN 112345
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
645 PM CDT Sat Apr 11 2026

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms tonight, with
  likely the highest coverage (~40 percent) over eastern Iowa; a
  few marginally severe storms possible.

- During a windy Sunday, rain will spread north across the area
  during the afternoon with embedded thunderstorm potential into
  the evening; again a marginally severe storm or two possible.

- Warm and seasonably humid air mass Monday through Wednesday
  will support periods of rain and thunderstorms, with some
  likely being organized posing occasional severe threats.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 240 PM CDT Sat Apr 11 2026

A gradually decaying mesoscale convective vortex (MCV) in
eastern Iowa this afternoon will continue some rain as it
tracks northeast through late afternoon. Our 18Z sounding
sampled minimal mid-level lapse rates, so any thunderstorm
potential is mainly in far southeast Iowa and northeast
Missouri through 7 P.M. Behind this MCV will be a brief period
(2-4 hours) of suppression limiting any shower development in
its wake.

Tonight...Satellite water vapor imagery and regional mid-level
VWP data indicate multiple small short waves upstream back as
far as the Central Plains that will traverse over at least the
western CWA (eastern Iowa) tonight. A strengthening low-level
jet over the region will support continued warm air advection
aloft (WAA) and moisture transport that these subtle waves can
interact with. Not surprisingly, CAMs show a plethora of
solutions, but generally scattered convective coverage that
ranges a little higher with northwest extent in the CWA.
MUCAPEs are on the order of 200-500 J/kg and of a tall and
skinny variety, with deep layer shear near 30 kt. That might
mean mainly small hail with any persistent cores.

Sunday and Sunday night...As a 995 mb low pressure gradually
deepens across the Northern Plains on Sunday, south-southwest
winds will increase over the area and probably will do so early
in the day (7-10 AM). Depending on the amount of solar
insolation in the morning, which is low confidence as it could
be cloudy with still some spotty convective activity, sporadic
40 mph wind gusts could result. During the afternoon within the
residual moisture transport plume, a short wave is forecast to
track northeast across the CWA, with some longitudinal spread in
guidance. Either way, high PoPs remain in order especially mid-
afternoon through evening. Ahead of this wave in the far
eastern CWA (north central Illinois), some surface-based storms
may be able to pop with forecast temperatures in the mid 70s at
or slightly above the forecast convective temperatures. A strong
storm or two cannot be ruled out with this. Otherwise, within
the broader shield of rain there is some signal for embedded
thunderstorms, probably of a 20-30 percent coverage type.
Rainfall amounts Sunday afternoon just northwest of the short
wave center will probably see over one half inch of rain with a
30 percent chance of exceeding one inch per latest NBM data.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 240 PM CDT Sat Apr 11 2026

A broader western CONUS trough on Monday will gradually move
east-northeast and over the Midwest by Wednesday, potentially
acquiring a negative tilt as it does so. With a surface front
in the vicinity, likely oscillating some due to mesoscale
effects, this presents an active pattern in the region.

Monday...Confidence is high in the surface warm front lifting
north of the area by or during Monday morning. An elevated mixed
layer (EML) is forecast to move over, and deterministic
guidance generally is void of any short waves in that time. So
those two together currently indicate much of if not the entire
daytime could be quiet in our forecast area, and a warm and
increasingly humid one with high temperatures 75 to 80 favored
and dew points increasing into the mid 60s. Convective
development is most favored ahead of the low which currently is
in the southern Minnesota region later Monday. The right
entrance region of the jet is forecast to move a little more
north of east, while thickness diffluence would support
organized convection potentially tracking a little more south of
east and being more problematic for our area with a severe wind
threat Monday night. So tough to say at this point yet. Also,
some isolated low-level jet forced convective development may
sprout over our area Monday night as well.

Tuesday and Wednesday...The first low pressure weakens while a
second, stronger one deepens in the western to central Plains
Tuesday. This type of setup is common with a slow-moving western
CONUS upper trough. The surface boundary on most guidance is
forecast to be slightly north to over the area and likely
reacquiring warm frontal characteristic Tuesday P.M., although
that may depend on any mesoscale convective influences that are
simply too difficult to pinpoint at this distance. If no
convective effects, temperatures should be able to top 80
areawide with 15-17C under a southwesterly low-level jet and a
very warm starting point to the day (60s -- potential daily
record warm lows for April 14). Obviously with a warm front in
the area during mid-spring, that will be a time period to watch,
including possible heavy rainfall Tuesday night. As that low
approaches the area, possibly the best kinematics of the few
days spread over the area Wednesday, although timing differences
become much more evident in ensemble memberships and
deterministic guidance at this point. All in all, this presents
a 48 hour period or so from Monday night through Wednesday
evening with some severe weather threat, with specific
magnitudes and timing being more resolved as we draw closer.

Beyond...Pattern looks to stay active but possibly more
progressive during the latter half of next week. With no
significant cool air behind it, temperatures should remain
above normal.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 644 PM CDT Sat Apr 11 2026

MVFR conditions to persist for a few more hours at CID/DBQ
before improving to VFR. An increasing LLJ will bring a low
chance for scattered showers/isolated storms after midnight
primarily at CID/DBQ and opted to keep PROB30 wording for this
occurrence. LLWS around 1500ft to develop at all the terminals
and will persist through at least 12z. Attention then turns to
another shortwave that will bring scattered showers and storms
to much of eastern IA and northwest IL mid-morning through the
afternoon hours Sunday. Confidence in thunder mention too low to
include at CID/DBQ at this time, but have opted for PROB30
groups at MLI/BRL where higher confidence resides. In addition,
a strengthening pressure gradient will bring gusty SSW winds
over 30kts at times beginning late morning through the afternoon
hours.

Late in the period, MVFR cigs will move into eastern IA behind
the shortwave, with some guidance even hinting at IFR
conditions developing very late or just behind this TAF cycle.


&&

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

&&

$$

SHORT TERM...Friedlein
LONG TERM...Friedlein
AVIATION...Gross