Iowa City, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

457
FXUS63 KDVN 061954
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
254 PM CDT Fri Jun 6 2025

.KEY MESSAGES...

- Shower and storm chances (30-60%) this weekend, particularly
  each afternoon.

- Level 1 out of 5 severe weather threat (damaging winds) for
  portions of the area Sunday PM.

- Generally seasonal temperatures before warming up by mid-
  week next week.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 245 PM CDT Fri Jun 6 2025

Wildfire smoke may linger tonight as weak subsidence builds in,
and may foster a continuation of some hazy skies with minor
visibility restriction at times possible along with reduced air
quality. Otherwise, mainly clear to partly cloudy tonight and
seasonal with lows mostly in the 50s.

Saturday, a mid level shortwave will progress eastward from
the Central Plains reaching the lower Great Lakes by
late Saturday night. This will bring increasing chances for
showers. Best forcing and moisture favors the bulk of the
precipitation focusing to our south, but sufficient overlap
glancing our area to bring the likelihood (60-70%) of
rain near to south of I-80 from Saturday afternoon exiting in
the early evening. Deep layer shear 0-6km is 30-35+ kt could
support some potential for organized storms, although
instability appears to rather low with around 500 j/kg MUCAPE
and thus the severe weather threat appears to be rather low.
Rain amounts appear to be mostly light at 0.25 inch or less,
though some locally higher amounts are possible with any storms.
Heaviest rains should focus further south across parts of
Missouri. The increase in clouds should limit highs mainly to
the lower to mid 70s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 245 PM CDT Fri Jun 6 2025

A digging upper low to our north and attendant upper diffluence
and PVA coupled with a surface cold front will provide another
chance (40-60%) for showers and storms on Sunday. The timing of
the front has slowed to where the models indicate the potential
for more instability (1000-1500+ j/kg of MUCAPE) Sunday
afternoon, especially from around the QC metro on south and
east. Deep layer shear is strong enough (40+ kt) to bring some
risk for strong to even severe storms and SPC has expanded the
Marginal Risk /level 1 out of 5/ to include areas roughly along
and east of a Freeport, Illinois to Fairfield, Iowa line.
Timing looks to be mainly 2-7 PM, and could possibly be even a
smaller window with potentially storm motions at 40 kt. With
southwest low level flow and fairly unidirectional wind fields
through the mid levels the main threat would appear to be damaging
winds. Drier air post-frontal should bring a dry night Sunday
night into Monday morning.

With the upper low traversing the Great Lakes Monday into
Tuesday, we`ll continue with periodic shower chances with
perhaps the potential for a few storms as well as energy rotates
around the low and across the Midwest.

There is good agreement in the medium range deterministic and
ensembles on the upper low exiting Tuesday followed by mid/upper
level ridging. This should provide a stretch of dry weather with
a warming trend Tuesday into Thursday.

Beyond, there still remains increasing uncertainty late next
week on the strength of the ridge and subsequent PoP/temps. Some
guidance indicates a weaker ridge, which would allow for more
energy to plow through the ridge axis and lead to shower and
storm chances. Meanwhile, other guidance continues with a more
amplified ridge, which would support a continuation of drier and
warmer conditions.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1220 PM CDT Fri Jun 6 2025

Predominantly VFR conditions expected throughout the period along
with light winds. Brief visibility 3-6SM in haze/smoke is
possible at times, with low smoke concentrations near surface
trapped by weak vertical mixing this afternoon and subsidence tonight.

&&

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

&&

$$

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