300
FXUS63 KDVN 291516
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1016 AM CDT Mon Apr 29 2024

...Hydrology Update...

.KEY MESSAGES...

- Active forecast remains through the long term, with near daily
  chances for precipitation after Monday.

- Temperatures will remain above normal through midweek,
  trending towards normal for the end of the week.

- Recent rainfall, along with the forecast for more this week,
  will result in rises along area rivers. River flooding is
  currently happening on some rivers, with the potential for
  more through the week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 247 AM CDT Mon Apr 29 2024

Through the day today, the upper low slowly pushes northeast into
the northern Great Lakes. The associated surface low will follow a
similar track, with a cold front dragging through our area shortly
after noon. Any rainfall that we will see today will be confined to
the early morning hours, as the overnight showers push out of the
area. Moisture will be limited as we progress towards the afternoon
hours, which will allow for a dry frontal passage. With more dry air
working in, we will start to see clouds clear through the day as
well. Surface high pressure will slide through our south this
evening and tonight, which will allow for clear and calm conditions
overnight. Temperatures are forecast to drop into the 40s and low
50s tonight as a result.

A quiet start to the week is expected. Happy Monday!

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 247 AM CDT Mon Apr 29 2024

A few disturbances are forecast to pass through the flow midweek,
with the potential for a more potent wave to impact the area
Thursday/Friday. Much of the week, above average temperatures will
be seen, with most in the mid-upper 70s. Towards the end of the
week, temperatures moderate near normal, as we will be socked in
clouds and rain.

Tuesday, an upper wave will pass through the area, with the vort max
forecast to pass through that evening. Compared to the last forecast
package, this has gone down in intensity for our area, keeping the
strongest forcing just north of the area. Guidance is in general
agreement on seeing showers/storms with frontal passage that
evening/night, but there are some differences with moisture content.
The latest trend is for a line of strong to severe storms well west
of the area dying upon arrival in our area, leaving us with some
scattered showers and storms in a broken line. With the vort max
farther north, the best chance to see the stronger storms will be in
our northwest, if the line stays organized upon arrival. Timing is
generally captured well amongst guidance, with them also indicating
that this will move through quickly. SPC introduces a Marginal Risk
(level 1 of 5) for our western counties. Confidence is low on severe
potential, with the best chances west of the forecast area.
Although, we will continue to monitor as more short term guidance
comes in.

After that system, we will start to see a potent wave deepen over
the Rockies mid-late week. We will see a few leading impulses pass
through the area, leading to persistent showers/storms for the
remainder of the week. This will be a wet period, with the
potential to see quite a bit of rain. With recent rains and more
forecast, some rises along area rivers are expected. The parent
wave developing is the one that has our attention though.
Although, there is plenty of uncertainty with this, as well as
major timing differences amongst guidance. Although, all long
term guidance shows this system. If this wave deepens enough and
we get that negative tilt upon arrival, this will bring the
potential for strong to severe storms late in the week.
Although, it is too soon to say for sure. WPC is highlighting
our area in the risk for Excessive Rainfall from midweek through
the end of the week, as they are currently forecasting between
1-3+ inches of rain by the week`s end for some. Thus, flash
flooding will be possible, as well as rises along area rivers.
So, just be mindful and stay up to date on our forecasts!

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 520 AM CDT Mon Apr 29 2024

Spotty showers (20%) will linger through mid morning with the
passage of a weak cold front along with a period of
MVFR ceilings. There is a low chance (30%) of IFR ceilings
at KDBQ this morning. As diurnal mixing increases, MVFR ceilings
should lift to VFR late morning through mid afternoon. South
winds will veer to WSW and become gusty at 15-30+ kts. Weak high
pressure building in tonight will result in winds becoming light
and variable. Can`t rule out some patchy ground fog late in the
period (after 08z) given the recent rain and a steep, shallow low
level inversion, but confidence is too low for mention at this time.

&&

.HYDROLOGY...
Issued at 1006 AM CDT Mon Apr 29 2024

The flood warning in effect for the Skunk River at Augusta has
been cancelled this morning, as the river crested just below
action stage overnight and continues to fall this morning.

Elsewhere, flood warnings continue for Wayland (Fox River) and
Colmar (La Moine River). The former will drop below flood stage
this afternoon, while the later remains on track to see moderate
flooding through Wednesday as routed flow from overnight rains
work through the basin.

Heavy rains remain possible later this week again as forecast by
WPC. The timing of this rain would fall just past the crest on most
active tributary rivers. Keep a general awareness of rivers in the
week ahead, as this wet pattern continues to evolve.

&&

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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Gunkel
AVIATION...McClure
HYDROLOGY...Speck