734
FXUS63 KDVN 290717
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
217 AM CDT Sun Jun 29 2025

.KEY MESSAGES...

- Hot and humid weather continues today.

- A threat for storms is expected mainly tonight, with the
  highest chances from late evening into the overnight period.
  A few strong to severe storms are possible.

- The pattern looks to dry out for the early to middle part of next
  week.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 212 AM CDT Sun Jun 29 2025

A warm, humid, and clear night is found over eastern Iowa, northeast
Missouri, and Illinois through 2 AM.  Temperatures have cooled off
to the lower to mid 70s, and will likely not cool much more as dew
points are holding in the lower 70s.   While our weather is quiet,
much of Minnesota through SD and northeast NE has been dealing with
strong to severe storms since last evening. This activity is moving
east and southeast, and is showing signs of running into convective
inhibition as it approaches Iowa. With the LLJ positioned along the
Missouri river to SW MN axis, the remaining overnight storms should
move into western Iowa, and keep our CWA dry through the morning.

Much like yesterday, sunshine and a hot air mass will allow for
temperatures to rise to the lower 90s, with dew points of 70-74.
Heat index readings of 94-100 are expected, generally like
yesterday.

Today now appears to be mainly dry, as mid level capping is
expected, with an EML near 5000 ft. Even the most aggressive models
w/r/t convection today, show this deep warm layer aloft. This warm
layer should keep warm sector storms limited today, but not
impossible. I`ve kept pops very low through the afternoon hours,
mainly slight chances. We do expect storms to fire along the
approaching cold front this afternoon, or a modified position of the
front through storm outflow. These storms will require both
convergence along the boundary to form, as well as support from the
weak short wave passing eastward aloft. What that means for our
area:  we`ll be waiting.  While mesoscale storm interactions /
outflow could push this axis into our western counties towards 5-
7PM, it looks like the best threat for storms and better rain
coverage will be overnight as the warm layer aloft cools a bit, and
may be use the remaining mixed layer CAPE of 1K+ to form storms. In
general, I`ve greatly undercut NBM pops which came in at 60-80% for
this afternoon through tonight and Monday. I do not see a strong
signal that storms will be widespread enough to support this, but
the decrease in inhibition overnight does support high chance to
lower end likely 50-60% pops.

Monday, the short wave will be passing through the area, and
scattered storms/showers are possible through the day. Highs are low
confidence with clouds and showers around, but lower to mid 80s see
on target given the time of year, and very little CAA behind the
front.

QPF has now been reduced to under 0.25 for this entire event by WPC.
That said, the air mass definitely will support isolated heavy
rains.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 212 AM CDT Sun Jun 29 2025

Tuesday through Wednesday continues to be a dry period within our
forecast, as high pressure moves through the region in the wake of
the upper trof Monday. However, beyond that period, Thursday through
Friday may see some activity as warm air at lower levels builds
back into the region, with northwest flow aloft. This will
certainly offer a potential for showers and storms later in the
week, but little certainty in timing or placement at this point.


There are some early indications that Friday and Saturday will see
near advisory levels of heat once again as an upper ridge builds
over the region. That potential is a little vague out this far as
models have greatly varied in the extended forecast the past few
days.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1210 AM CDT Sun Jun 29 2025

A slow moving cold front will approach eastern Iowa Sunday
evening, though it may not pass through the area until Monday
morning. VFR conditions with light south to southeast winds can
be expected from late tonight through Sunday evening, when
scattered storms will enter the region. We will continue to
forecast a Prob30 for thunderstorms, but push that back until
the mid evening hours. Any storm would be capable of localized
IFR conditions in heavy rain, and variable gusty winds over 30
kts.

&&

.HYDROLOGY...
Issued at 220 AM CDT Sun Jun 29 2025

Forecast crests along portions of the Cedar River have continued
trend a bit lower into next week. All flood watches on the
Ceder have been discontinued. The flood warning for Marengo on
the Iowa River remains a low confidence minor flood warning.

&&

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

&&

$$

SHORT TERM...Ervin
LONG TERM...Ervin
AVIATION...Ervin
HYDROLOGY...Ervin