689
FXUS63 KDVN 021744
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1244 PM CDT Thu May 2 2024

...Updated for 18z Aviation...

.KEY MESSAGES...

-  Upper level pattern remains active, with periodic chances for
   showers and storms through next week.

-  There is the risk for heavy rain and a Marginal Risk for
   Severe Weather today and into this evening.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 247 AM CDT Thu May 2 2024

A mild and wet day is expected throughout the forecast area today,
as a slow moving upper low passes north of the area. At the surface,
warm advection showers and storms will start the day, as the warm
front associated with the surface low passes through the area. With
that, the surface low will track southwest to northeast, skimming
our far northwest. Cold front will also pass through late this
afternoon and evening, which will be another focus for further
showers/storms this afternoon and evening. PWATs between
1.25-1.50" will be seen in a narrow axis along and west of the
Mississippi River, which will serve as a corridor for heavier
rainfall. These areas may see anywhere between 0.75-1.50" of
rain, with locally higher amounts possible. While we have a
Slight Risk for Excessive Rainfall in these areas, our
confidence remains low on the flash flood threat, as these areas
are abnormally dry or in drought. Thus, the ground should be
able to easily soak up much of the rain. Main areas that may see
some impacts will be urban centers.

We will have a low-end severe risk as well, with the SPC
highlighting our whole area in a Marginal Risk (level 1/5).
Confidence in this is low at the moment, with our focus being on
areas along/east of the Mississippi River seeing the best chance for
any strong to severe. Instability will be lacking throughout the
area, as dense cloud cover and rainfall will be seen through much of
the morning. Areas east of the Mississippi will miss out on much of
the rain early on, which may allow them to build more instability.
If we can get that, the shear is more than sufficient to favor
strong to severe storms. If we end up seeing strong/severe storms,
main hazards will be wind and hail, with the tornado threat being
secondary.

Much of these showers and storms will continue into the evening,
decreasing in coverage from west to east overnight. Much of the area
should be free of rain by sunrise Friday. Temperatures overnight
will stay relatively mild, with most in the 50s, thanks to residual
cloud cover moderating the temperatures.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 247 AM CDT Thu May 2 2024

Pattern remains active through at least the first half of the long
term period. Upper wave from Thursday continues to trek northeast
through the northern Great Lakes, with another wave digging south
into the area on Saturday. Much of Friday appears to remain dry
after the bulk of the precipitation pushes east, with more showers
and isolated storms approaching the area Saturday. Severe weather is
not expected Saturday. Rather, it is looking to be a gloomy day,
with light rain.

The next system to bring heavier rain and storms will be early next
week, as a deepening wave over the Rockies pushes into the Plains,
becoming negatively tilted and quickly punching through the Upper
Midwest Monday night. Although, that trough of low pressure stalls
over the northern US, slowing filling in and weakening. While that
remains north of the area, bouts of energy passing through may bring
the chance for persistent showers and gloomy conditions. There is
much uncertainty with how this will play out, generally given the
lacking moisture. While this does not seem to be a washout by any
means, there will be nearly daily chances for precipitation next
week, with plenty of dry periods in the mix as well.

Temperatures next week will be similar to what we are seeing now,
with much of the area remaining in the 70s to low 80s. Thus, aside
from the rain chances, it should be a nice week!

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1233 PM CDT Thu May 2 2024

An active TAF period is in store for the area thanks to a nearby
cold front and an approaching disturbance aloft. Rain showers
currently in the KCID/KDBQ vicinities will give way to renewed
shower and storm development areawide in the next 2-4 hours,
with impacts expected mainly expected at KMLI/KBRL (TEMPO groups
have been included in this forecast). Conditions will
deteriorate to MVFR, with heavier showers and storms bringing
brief drops to IFR. There is a low risk that these storms will
be severe, with the primary risks being variable wind gusts
around 40-45 kts and large hail. These storms will move east by
03.00z, with leftover MVFR rain showers and ceilings along the
front persisting through the evening hours. Conditions will
improve to VFR after 03.06z, with gusty winds decreasing and
veering to the north.

For Friday morning, latest CAMs are hinting at fog development
at KCID/KDBQ thanks to leftover moisture from rains from this
morning. However, this is low confidence, so have only
introduced a brief drop to MVFR visibilities. Look for more
detail in this from later shifts.

&&

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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Gunkel
AVIATION...Speck