Iowa City, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

142
FXUS63 KDVN 042353
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
653 PM CDT Mon May 4 2026

...00z Aviation Update...

.KEY MESSAGES...

- Gusty winds will be seen this afternoon and evening as a cold
  front passes through. Gusts upwards to 25-35 mph will be
  possible, which may result in localized/brief visibility
  reductions due to blowing dust.

- Scattered showers and storms will pass through the area this
  afternoon/evening, where a few strong to severe storms will be
  possible.

- Below normal temperatures are expected Tuesday through the
  remainder of the week, gradually increasing at the end of the
  week, with low-end chances for light rain showers.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 221 PM CDT Mon May 4 2026

This afternoon and evening, strong mixing will result in gusty winds
throughout the area, with southwesterly winds ahead of the front and
north-northwesterly behind. We will generally see gusts between
25-35 mph, but a few higher gusts cannot be ruled out. This
will especially be true for areas along the approaching cold
front and for a few hours after frontal passage into tonight.
This may result in localized areas of blowing dust, as we have
seen over the weekend. Although, it should be localized and
result in brief visibility reductions if we do see some blowing
field dust.

Broad upper trof over the Upper Great Lakes region will slowly sag
south through the evening and night, with strong westerly flow set
up along the southern edge of this. This westerly flow starts out
towards the Rockies, which will help guide weak waves toward the
area through the night and tomorrow. Although, this
afternoon/evening we will see a cold front pass through the area,
associated with the seasonally strong surface low north of the Great
Lakes Region. Along this cold front, we will see isolated-scattered
showers/storms develop and pass through the area from northwest to
southeast. We can see showers/storms develop as early as 4PM north
of I-80, but confidence on the start time is lower owing to plenty
of dry air present. Coverage will gradually increase along the front
between 4-6PM, with better chances/coverage for areas south of I-80,
especially after 6PM. A few of these storms may be strong to severe
later this afternoon and evening. A look into model soundings would
favor wind being the primary threat, owing to plenty of dry air
resulting from strong evaporative cooling, with hail being
secondary. The better threat to see any hail will be south of I-80,
generally along/south of Highway 34. CAM soundings indicate better
instability (1500-2000 J/kg CAPE) and decent mid-level lapse rates
for hail in those areas.

By around 10PM, we should see the strongest storms move out of our
area, leaving us with post-frontal showers and storms through the
remainder of the night. The nighttime activity should largely remain
along/south of the Highway 34 corridor. Although, these will also be
relatively scattered in nature. QPF for the event as a whole will
remain low, with the whole area generally seeing <0.10-0.25".
Residual cloud cover will help moderate temperatures in the upper
40s tonight, with much of the area remaining dry. As we go into
Tuesday, we remain under influence of the large upper trof sitting
over the north-central CONUS. With that, weak bouts of energy will
continue to pass through the area, brining on/off showers and storms
tomorrow for areas along/south of Highway 34. This will not be a
washout, with QPF remaining low. Rather, a gloomy day with cooler
air and cloudy skies will be seen. For the remainder of the area, we
will see quite the change from the previous couple of days
temperature-wise, with post-frontal airmass keeping us in the upper
50s to low 60s. Winds will remain light and out of the north, with
mostly cloudy skies throughout.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 221 PM CDT Mon May 4 2026

Wednesday... A high pressure anchors well to the west, with
a surface low north of the Great Lakes Region, advecting in
cooler air from the north. Temperatures are forecasted to be
5-10 degrees below average for this time of year with highs in
the mid-50s to low 60s and lows in the mid-30s to low 40s. Some
clouds will stick around due to cyclonic flow aloft over the
region.

Thursday... The longwave trough that has been lingering over the
Northern Plains for the first half of the week will finally eject
off to the east, pulling a shortwave southeastward with it. A 500 mb
vorticity maximum is forecasted to pass across Iowa on Thursday
providing some lift for light rain showers as winds shift from
northerly to westerly. This will kick off a warming trend as highs
climb into the mid-60s.

Friday-Sunday... Northwest flow aloft returns with the potential for
a couple shortwave passages, similar to a clipper pattern. A weak
front Friday could bring additional showers with southwesterly flow
at the surface, bumping highs closer to 70. Saturday will be mostly
dry before the ECMWF ensembles and GEFS hint at a mid-level
frontogenesis band developing to our south across Missouri ahead of
a surface low deepening over the south-central Plains. This could
bring some stratiform rain into southern Iowa, but there is general
uncertainty in the northern extent of this precipitation and amounts.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 645 PM CDT Mon May 4 2026

The sctrd line of thunderstorms are south of almost all the TAF
sites except BRL and will have to use TEMPO through 9 PM at BRL
for passing thunderstorms with gusty winds and at least small
hail. Otherwise a cold front producing the storms will continue
to sag southeastward through the area with sfc winds veering to
the northwest and becoming gusty for 1-3 hours after FROPA
before diminishing some by mid to late evening. We will also
have a temporary cloud clear out through midnight, before a
post- frontal mid deck slides back in from the west. Some light
rain may try to spread in from the west late tonight and into
Tuesday morning especially south of I-80 and mainly effecting
the BRL site. Overall it may be mainly VFR late tonight and
Tuesday, with the BRL site having the potential for flirting
with MVFR VSBYs from rain Tue morning. Northwesterly sfc winds
of 10-15 KTs re-establishing by Tue afternoon.

&&


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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Delaune
AVIATION...12