-- Discussion containing changed information from previous version are highlighted. --
645
FXUS63 KDVN 232341
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
641 PM CDT Mon Sep 23 2024

.KEY MESSAGES...

- Near normal temperatures to start the week will become
  slightly above normal by weeks-end, with most in the upper
  70s.

- Light precipitation will be seen tonight and into Tuesday
  morning, with chances dropping off until late in the week.

- Much uncertainty remains on the forecast from Friday and
  through the weekend, owing to interactions between a potential
  tropical system and cutoff upper low.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 142 PM CDT Mon Sep 23 2024

Weak wave and attendant surface low currently draped over Missouri,
forecast to progress northeast slowly though the day and night, as a
deeper wave quickly digs in from the north. This stronger wave will
bring in much dryer air through midweek. Although, prior to that,
the weaker wave will pass through tonight, bringing the chance for
precipitation as it exits. The rain will be far from widespread and
heavy, with the main areas seeing the bulk of the precipitation
south of Interstate 80 and east of the Mississippi River. Current
guidance favors anywhere between 0.10-0.25" of rain for those that
see the scattered showers. Isolated thunder cannot be ruled out,
owing to some low MUCAPE, but confidence remains low. Cloudiness
tonight will help moderate temperatures a bit, with most remaining
in the mid-upper 50s.

Tomorrow, with the surface low in close proximity still, we will
continue to see clouds throughout much of the area. Through the day,
cloud coverage will start to scatter out and clear from northwest to
southeast. Precipitation chances will be limited to those east of
the Mississippi River tomorrow, with much of the area being dry by
noon. Conditions tomorrow will be very similar to those seen today,
with widespread temperatures near 70 and a light breeze.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 142 PM CDT Mon Sep 23 2024

Midweek will remain quiet, as the wave that digs into the region
Tuesday filters in much dryer air. Dry air and a northerly wind will
result in beautiful weather, with temperatures in the mid 70s and
mostly clear skies. Confidence in this for Wednesday and Thursday
remain high, with decreasing confidence as we progress to the week`s
end and the weekend.

Towards the end of the week, the forecast grows more uncertain.
Guidance is hinting at the potential for quite the tropical low to
develop over the Gulf of Mexico, with a northerly trajectory. This
will interact with the forecast cutoff low over the southeastern US,
which resulted from the wave digging in our area Tuesday, bringing
us the beautiful weather. How these two systems interact remains
uncertain. A lot of this will be determined by the track of the
potential tropical cyclone, which will be directly impacted by the
cutoff low over the same area. Thus, we will have to monitor how
these two features interact. Although, the farther east that the
potential tropical system stays, the dryer the weather would seem
for us. We will remain under largely easterly flow due to this
pattern, which isn`t quite favorable for moisture return. Guidance
seems to have followed this thinking in the last couple of runs, as
they keep us dry through part of the weekend. The wildcard remains
the path of the potential tropical system and its post-tropical
counterpart. As the last discussion alluded to, we may see a
Fujiwara interaction with the upper low and potential tropical
system, which can work to pull the post-tropical low counter-
clockwise around the cutoff low, bringing a larger pool of moisture
towards our forecast area. Thus, that scenario would result in
precipitation chances for the area. Latest forecast trends are
trending a little wetter, which would be a result of the second
scenario. Unfortunately, much uncertainty exists though, especially
with the fact that we still have yet to see a tropical cyclone
form. Thus, stay tuned for future updates.

Aside from potential precipitation chances this weekend, the long
term looks to remain near normal, temperature-wise. Any increase in
cloud cover due to the weather system(s) may lead to impacts to
temperatures. So, plenty of unknowns lie ahead of us. One thing that
I can mention is that we are not expecting widespread heavy rain,
nor severe weather, at this moment. While this is subject to change,
confidences in any severe weather locally remains low.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
-- Changed Discussion --
Issued at 641 PM CDT Mon Sep 23 2024

We continue to expect a mixed bag in terms of flight category
impacts over the next 18 hours. A trough of low pressure is
expected to support increasing chances of showers tonight,
mainly across our southeastern areas, including the BRL and
MLI TAF terminals. Confidence remains highest for MVFR/IFR
conditions for BRL, but more uncertain on IFR conditions for
MLI. CID and DBQ appears to be too far northwest to really get
into the low stratus and showers, but we will have to watch
just how far this stratus deck reaches. If showers can become
heavy enough, MVFR visibility reductions appear most likely.

Easterly winds this evening will become more variable overnight,
becoming more northerly during the daylight hours Tuesday,
around 5 to 10 knots.
-- End Changed Discussion --

&&

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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Gunkel
AVIATION...Schultz