637
FXUS63 KDVN 290812
AFDDVN

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

.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 /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1237 AM CDT Mon Apr 29 2024

VFR to MVFR conditions are being seen throughout, but will
continue to trend all VFR by 12z. Spotty showers are being
seen, but we are not expecting much of an impact from these.
BRL will be the terminal that sees more of an impact, as they
are along an area of stratiform rain, with lower cigs. Winds
will remain out of the south tonight, shifting southwesterly and
gusting upwards to 25 KTs by 18z. Cloud cover will start to
decrease through the day as well.

&&

.HYDROLOGY...
Issued at 1124 AM CDT Sun Apr 28 2024

Rainfall over the past 24+ hours has resulted in mostly within bank
rises on area rivers, especially across the southern CWA where the
heaviest rains of 1-2+ inches has also resulted in flooding on
portions of the Fox River and La Moine River. The Fox River appears
to be cresting early this morning below the forecast of moderate
flood stage. Some rain has occurred early this morning, but mostly
east of the basin. Will await the new forecast later this morning,
but barring anything unforeseen confidence is lowering on it
reaching moderate flood stage. The Skunk River at Augusta is still
forecast to reach minor flood stage today, but the latest trends
show the river may be close to cresting at near action stage.
Similarly it appears that most of the QPF overnight has stayed
mainly east of the basin, and therefore confidence in it reaching
flood stage is lowering. Lastly, the La Moine River at Colmar is
above moderate flood stage. The basin did see additional rain
overnight, however it appears to be lower than forecast and as
such it may likely crest a few tenths of a foot lower over the
next 12 hours.

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...Gunkel
HYDROLOGY...McClure