526
FXUS63 KDVN 042344
AFDDVN
Area Forecast Discussion
National Weather Service Quad Cities IA IL
544 PM CST Wed Mar 4 2026
...Updated for 00z Aviation...
.KEY MESSAGES...
- Challenging forecast continues through Friday night with
several rounds of showers and thunderstorms tonight through
Friday night.
- There is a level 2 out of 5 risk for severe thunderstorms
Friday into Friday night. There are two rounds possible; One
on Friday morning and a second Friday night.
- Near record high temperatures possible on Friday. Above normal
temperatures continue into next week.
&&
.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 112 PM CST Wed Mar 4 2026
Currently, an MCS is passing well to our south across the
Interstate 70 corridor with trailing precipitation moving into
Hancock and McDonough Counties. A rumble of thunder is possible
this afternoon. Rainfall amounts will be light with some mist
or drizzle to the west in far northeast Missouri and southeast
Iowa. Confidence is low on precipitation to the west of the MCS
reaching the ground, with drier air on east to northeast winds
across the area.
In the near term, water vapor shows a strong shortwave trough at
500 mb moving into the central Plains. The model consensus
has this neutrally tilted shortwave moving across the area
tonight with the best lift arriving by midnight and continuing
overnight as a weak low level jet develops. Showers and a few
thunderstorms are forecast to develop, but have still lowered
chances slightly due to lower coverage on the CAMs overnight.
In the wake of the morning convection, shortwave ridging is
forecast to build back into the area and bring quiet weather
during the day on Thursday. Like this morning, patchy dense fog
is possible through the mid morning hours especially if rain is
light overnight. High temperatures on Thursday will be
noticeably warmer and range from the lower 50s along the Highway
20 corridor to lower 60s in Scotland County MO and Van Buren
County IA.
Late Thursday into Friday, the flow aloft will become more
amplified as a deeper trough moves into the Intermountain West
with a stronger shortwave ejecting northeastward into Nebraska
and Kansas by 00 UTC Saturday. Shortwave energy ahead of this
wave is forecast to bring increasing chances of showers and
storms late Thursday night into Friday morning. A stronger low
level jet Friday morning may lead to greater shower and
thunderstorm coverage than tonight. The best window for showers
and storms is 4 AM to 10 AM Friday. Hail will be the main
concern with any of these storms with elevated CAPE across the
area.
Confidence in precipitation timing is lower for the second round
of storms late Friday afternoon into Saturday morning across
the area with differences in the location of the warm front
Friday as well as the timing of the cold front and best lift
Friday night with it being possibly as late as Saturday morning.
The cold front will be nearly parallel to the the winds aloft
allowing for a slower frontal evolution. This will cause warm
temperatures and higher dewpoints to linger across the area
Friday night with temperatures in the 60s as late as midnight or
06 UTC.
A potentially slower cold front will offset the storms from the
better thermodynamics with model forecasts showing 500 J/KG of
MUCAPE. Deep layer shear is strong at 60 to 70 knots Friday
night as the better kinematics overspread the area. However the
shear vector will be oriented along the front meaning that
storms will tend to stay closer to the front and lift along it.
CAPE profiles in the NAM and GFS are tall and skinny meaning
that damaging winds will be the main threat as a QLCS moves
across the area. The 0 to 3 KM shear vector is also oriented
parallel to the front so mesovortex and tornado potential will
depend on any storms that accelerate toward the northeast.
Even if thermodynamics are weak, the synoptic environment will
still result in winds near severe limits with winds near 60
knots just above 850 mb.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 112 PM CST Wed Mar 4 2026
This Weekend-Early Next Week...strong northwest winds behind
frontal passage will start the period with decreasing clouds. A
beautiful stretch of weather is forecast this weekend with dry
conditions and comfortable humidity. Timing of the frontal
passage friday night into Saturday will cause high temperatures
on Saturday to occur early in the day with temperatures during
the day ranging from the upper 40s in east central Iowa to the
mid 40s in west central Illinois. Highs in the upper 50s and
low 60s is forecast Sun, with even warmer temperatures back
closer to 70 degrees on Monday! The roller coaster temperatures
continue.
Split flow is forecast to develop across the CONUS by midweek as
a trough is forecast to dig from southern Canada into the Upper
Midwest and bring chances of precipitation to the area by the
end of the period with temperatures dropping into the 40s by
midweek.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 535 PM CST Wed Mar 4 2026
In general expecting a degradation to widespread IFR/LIFR
conditions in low clouds and fog tonight across the terminals.
Areas of VLIFR in dense fog is possible, particularly at KBRL
and KMLI toward 06z and through 15z Thursday. Areas of drizzle
will also be possible with the lower clouds at times through
Thursday morning. Late tonight and through mid morning on
Thursday a system will bring a chance (30-50%) for showers
and isolated storms. This was handled with a PROB30 mention
for showers at KMLI and KBRL which look to have the best
potential. Lightning is possible as mentioned, but confidence is
too low. Guidance supports a gradual improvement to IFR and
MVFR by Thursday afternoon with the potential for VFR at KBRL.
&&
.CLIMATE...
Issued at 1222 PM CST Tue Mar 3 2026
Record High Temperatures:
March 6:
KBRL: 73 in 1910
KCID: 73 in 2005
KDBQ: 69 in 2000
KMLI: 73 in 2005
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.
&&
$$
SHORT TERM...Cousins
LONG TERM...Cousins/Ervin
AVIATION...McClure
CLIMATE...Gross
NWS DVN Office Area Forecast Discussion