513
FXUS63 KDVN 161740
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1240 PM CDT Wed Apr 16 2025

.KEY MESSAGES...

- Nice seasonable to slightly above normal day today.

- Isolated to scattered elevated showers and thunderstorms possible
  late tonight.

- Unsettled weather pattern still looks in line for Thursday through
  Friday with some severe potential.

- Another storm system possible on Sunday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 315 AM CDT Wed Apr 16 2025

Today...A fair weather and seasonable mid April day on tap as a weak
sfc ridge migrates eastward acars the region. Increasing
southeasterly LLVL return flow by afternoon and some insolation to
help boost temps well up in the 60s for most of the area.

Tonight...Approaching ridge-riding short wave and classic looking 30-
45 KT southwesterly LLJ converging acrs the area with it`s plume of
THTA-E advection, will look to spark isolated to sctrd elevated
showers and thunderstorms acrs the CWA mainly after midnight
tonight. Mid layer Thermo and kinematics even suggest a little more
robust cell may be able to produce at least some small hail into
Thursday morning. Ongoing 10-20 MPH southeasterly sfc winds will
make for a milder night in the 50s to upper 40s.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 315 AM CDT Wed Apr 16 2025

Thursday...Would expect Thu morning to be unsettles as the wing of
elevated showers and storms continues to spread east and northeast,
maybe not making it out of the local CWA until midday or early
afternoon. Then as broad southwesterly steering flow sets up from
the southern Rockies to the northern GRT LKS, increasing EML acrs
the area and ongoing LLVL return flow may lead to a mainly dry
warming Thu afternoon and early evening with temps getting boosted
into the upper 60s to low 70s with sfc DPTs in the 50s.

Thu night, many indications suggest the renewed convective
development zone will lay out along LLVL convergent zone from
the IA/SD/MN tri-state region and eastward acrs southern MN/IA
border into WI. With the ongoing fcst sounding indicated strong
capping EML in place, this activity would stay north of the
local area into Friday morning. But other supercellular
convection that will look to develop in high shear and better
heating area late Thu afternoon and evening acrs eastern NE and
the mid MO RVR Valley, will look to propagate eastward acrs IA
elevated style feed on a 40-50 KT southwesterly LLJ. If they can
maintain overnight and make it into the DVN CWA from the west
still mainly in supercell mode, again high effective storm layer
shear and optimum thermodynamics in place would support large
hail. With any pressure perturbation in a strong cell, couldn`t
rule out a damaging microburst as well.

Friday...Definitely an uncertain convection mode and development day,
with what ever happens and lingers out of Thu night effecting the day
Friday and the models can`t pick up on this. But the latest suite of
ensembles suggest a progressive enough sfc wave and front into the
GRT LKS with a trailing front down into the southern plains that we
may get lucky and the new forced convection takes off just to the
east and south of the DVN CWA Friday afternoon and evening. Current
Day 3 marginal and slight risks are laid out acrs the east half of
the CWA as a precaution, but if the latest trends are on it these
outlooks are too far west. Temps a real challenge depending on
storms lingering out of Thu night and especially frontal
placement/progression speed. The current loaded blend has an 80 in
the east, and low 60s in the far northwest.

Saturday through Tuesday...If current synoptic scale wave timing has
any idea, Sat would be a cooler post-frontal day with some
overrunning showers still possible in the south. Then eyes turn to
the next large wave piece to eject out of eastern Rockies/Plains
upper trof. How far north or south it goes and phasing takes shape
is still very uncertain with ongoing model descrepancies. But late
in the weekend into early next week will be a window to watch for a
potentially strong storm system to lift out somewhere acrs the mid
CONUS.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1240 PM CDT Wed Apr 16 2025

VFR conditions will prevail through the period with southeast
winds becoming gusty Thursday morning. Kept PROB30 storm
chances in for pre-dawn and morning hours. Some MVFR conditions
will be possible with storms. Lower ceilings will be possible
Thursday morning and beyond the end of the period, but opted to
only introduce MVFR cigs for now at CID, MLI, and BRL.

&&

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

&&

$$

SHORT TERM...12
LONG TERM...12
AVIATION...14