135
FXUS63 KDMX 102302
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
602 PM CDT Fri Jul 10 2026

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- Scattered showers and storms this afternoon into evening
  mainly in southern Iowa. While an isolated strong storm is
  possible towards the IA/MO border, widespread severe weather
  is not expected. Spotty heavy downpours are likely. Conditions
  are also favorable for funnel clouds.

- Patchy fog possible again overnight into early Saturday in
  mainly western and northern Iowa, where skies clear faster.

- A strong upper level high pressure ridge will set up over the
  central U.S. this weekend into next week, bringing mostly dry
  conditions and very warm temperatures Sunday and beyond.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 237 PM CDT Fri Jul 10 2026

Main focus in the short term is on the MCV out of Nebraska this
morning has developed showers and storms over northern Missouri into
southern Iowa as expected early this afternoon. The environment is
fairly similar to yesterday with around 1500 J/kg of MLCAPE, higher
at the surface, though with weak capping still in place. Shear
remains very weak, less than 10 knots in much of the area, with
slightly higher values closer to 25-30 knots right along the IA/MO
border. With the weak shear, and as noted in the previous
discussion, it will be difficult for storms to organize and maintain
the further north you go (north of about I-80). South of I-80, and
especially right along the IA/MO border the parameter space is a bit
better and would be the location should any stronger storms be able
to develop/maintain in our area with a risk for some brief hail or
gusty winds. This is in line with the SPC Day 1 Level 1 of 5
Marginal Risk that goes up to the IA/MO border. In between the IA/MO
border and about I-80, we have already seen showers/storms initiate
and while the severe threat remains low in this area with the
conditions already discussed, the weak shear is leading to slow
moving storms which could easily lead to some locations receiving
some heavy downpours and rain totals adding up quickly given the
nearly stationary to slow moving nature of the storms and pwats of
around 1.5". Some minor flooding could be possible should one of
these storms occur over a poor drainage or urban area, though
widespread flooding is not expected with this area of southern Iowa
most able to take rain with 3 hour flash flood guidance closer to 3-
4". Severe storms and flash flooding already ongoing in northern
Missouri are not far away from our southern coverage area border so
we will certainly watch these storms and rainfall amounts closely.
Just like yesterday as well, the environment does remain quite
favorable for funnel clouds with an area of overlapping surface
vorticity and 0-3 CAPE in southern to portions of eastern Iowa.
This is once again highlighted well with the non-supercell
tornado parameter in SPC Mesoanalysis with a few funnel clouds
already reported with developing showers in southern Iowa early
this afternoon. This will likely continue with developing
showers until around sunset. Have covered this area with a SPS
for the funnel clouds.

Storm coverage today will largely be diurnally driven and should
start to wane by around sunset. Dry conditions return late this
evening and continue through Saturday, outside of a stray shower in
the south, with models continuing their southerly track for storms
on Saturday as noted this time yesterday. The residual moisture
could lead to patchy fog development again overnight into early
Saturday as skies begin to clear with the light winds expected to be
in place. The most likely locations are in the north and west with
cloud cover hanging on longer in the south and east. Temperatures
remain more seasonal through Saturday with highs in the mid 80s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 237 PM CDT Fri Jul 10 2026

Dry and increasingly warm conditions are forecast from Sunday
through much of next week as an upper ridge builds and tracks
eastward through at least mid week. High pressure at the surface
will keep winds light and skies mainly clear outside of some
diurnal cumulus at times. Southerly flow starts to return early
in the work week leading to warming temperatures in the upper
80s to low 90s Tuesday and beyond with heat indices topping out
around the mid to occasionally upper 90s at times. Certainly
warm, but looking to be below heat headline criteria.
Precipitation chances then return later in the week in at least
the east into Friday, though at this time range there is still a
fair amount of model spread and plenty of time to refine the
forecast.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 602 PM CDT Fri Jul 10 2026

While VFR conditions are expected through the period, there are
several challenges as well. Showers with embedded storms are
most numerous over southern Iowa at the start of the period with
another storm southwest of ALO moving to the southwest.
Expectation is storm near ALO will be outside of the VC area by
the start of the period. Confidence is no higher on impacts at
OTM so will continue PROB30 for a few hours this evening.
Otherwise, patchy fog is forecast to develop toward sunrise
Saturday over western Iowa and will monitor trends to see if any
light fog is needed in the terminals in future issuances.
Diurnal cumulus is expected to develop mid to late morning
Saturday that should dissipate near the end of the period.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...05
LONG TERM...05
AVIATION...Ansorge