182
FXUS63 KDVN 091050
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
550 AM CDT Mon Mar 9 2026

...Updated for 12z Aviation...

.KEY MESSAGES...

- Near record/record high temperatures today, and are possible
  again on Tuesday mainly south of I-80.

- Severe weather potential late Tuesday afternoon through
  evening with all hazards in play. The greatest threat area is
  mainly near/southeast of a line from Sterling to the Quad
  Cities to Mount Pleasant where an Enhanced Risk (level 3 of 5)
  is in place. Localized flooding is possible with any repeated
  rounds of storms.

- Active pattern for the latter half of the week into the
  weekend with additional precipitation chances, some of which
  could be snow as temperatures turn cooler and more seasonable.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 333 AM CDT Mon Mar 9 2026

Anytime you start your day off with temperatures near normal highs
you know you`re headed for an anomalously warm day. Low level
warm advection will continue to strengthen for much of the day
ahead of an approaching cold front. Progged 850 hPa temperatures
of 12c to 15c are greater than 99th percentile of climatology
per NAEFS and at or above the max for DVN for the date per SPC
sounding climatology. This anomalously warm airmass combined with
abundant sunshine and a favorable southwest low level flow will
lead to record breaking highs in the 70s for areas south of Hwy 30.
The cold front, which currently is just north/west of the Twin
Cities early this morning, aided by a 5-7 mb post frontal pressure
rise is slated to make inroads this afternoon north of Hwy 30.
This will result in highs there in the 60s, albeit still well above
normal and even potentially still near record territory as evidence
by the 65 record high at Dubuque - see the Climate section below.

The cold front is expected to continue sagging south into the
area tonight, but with weakening post frontal pressure rises and
alignment more parallel to the mid level flow it is expected to
slow and eventually stall out most likely south of Hwy 30 to I-80.
This will lead to quite a low temperature contrast across the
area with lower 40s and possibly a few upper 30s near Hwy 20 aided
by veering flow to the northeast with a chilly Lake Michigan
influence (water temps upper 30s and 40s). Meanwhile, south of the
front an unseasonably mild night is in store with lows in the
50s. The most challenging low temperature forecast and subsequent
higher error bar (greatest uncertainty) will be along the Hwy 30
through I-80 corridors. Can`t rule out some fog development near
to just south of the boundary, but lower confidence as we
potentially develop some stratus with the nocturnal LLJ and also
could bring in some high clouds ahead of our next system.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 333 AM CDT Mon Mar 9 2026

Tuesday remains a day to be vigilant for severe weather, particularly
from QC metro and especially points south/east where SPC continues the
Enhanced Risk or level 3 of 5 risk. All hazards are possible, though
greatest concerns are for supercells yielding a significant hail threat
(golfball size or larger) and a few tornadoes in/near the quadrant
mainly S/E of the Quad Cities into northeast MO and central IL.
This zone has the overlap of the best instability and an impressive
kinematic environment in the pre-frontal warm sector ahead of a
surface low translating eastward along the frontal zone. This setup
like most has some uncertainty. This includes the potential for a
weaker and somewhat nebulous surface low, which is likely tied to
the continued slight slowing of the main synoptic scale ascent
attendant to the phasing of a Rockies shortwave and an ejecting
low from the Baja of California. Large scale height falls
(100-150+ m at 500 hPa) don`t overspread the area until late
Tuesday night into Wednesday, thereby casting some uncertainty
with timing/arrival of forcing, strength of the surface low and
amount of backed low level flow. Soundings also show the
presence of an EML, which in the absence of ascent will likely
suppress convection for much if not all of the daytime hours on
Tuesday. That being said, it would seem as though an increasing
40+ kt nocturnal LLJ should support some development probably
closer to 00z in/near our south/east service area into the
evening. With the presence of the earlier EML and given the
impressive kinematics we will likely see discrete supercells if
storms do indeed fire. The 03z RAP and 00z NAM/HRRR models also
show a 50+ kt jet max shown to overspread SE Iowa and WC
Illinois around 00z through 03z. The current SW to NE
orientation would place the favored right entrance region or
favorable lift quadrant largely just south/east of our service
area or very nearby for a close shave. Something else of note is
the Bunkers right Supercell motion is roughly 250-260 degrees
at 25-35+ kt. Thus, with that motion there will be the potential
for discrete surface based supercells with a tornado threat to
cross the front and become elevated reducing the threat to large
hail. Where this occurs will be pending the location of the
front, but consensus seem to favor between I-80 to Hwy 34...
thus south of Hwy 34 would stand the best potential for sustained
tornado producing supercells or even further south/east as it
looks right now.

Bottom line, the potential is there for significant severe weather
Tuesday late afternoon through evening, so you`ll want to pay
close attention to the weather especially for areas from the Quad
Cities south/east into central IL and northeast MO.

This severe threat will likely diminish mid to late evening, but the
arrival of the deeper synoptic scale lift and residual boundary
will support additional rounds of showers and storms, particularly
south of Hwy 30 and especially near/south of I-80. With PWATs
of 1.1 to 1.3 inches or roughly 2+ sigma there is the potential
for localized flooding with any repeated rounds of convection and
heavy downpours. 00z HREF LPMM through 00z Wednesday shows pockets
of 1-2  inches and ensemble means continue to hint also at a swath(s)
of similar amounts 1-3 inches. WPC ERO continues to highlight
south of I-80 with a Slight Risk for excessive rainfall. Due to
the ongoing drought much of the area will see beneficial rainfall,
but any areas again that get into repeated activity given the
anomalous moisture could wind up with several inches in a short
time that could result in a flooding threat.

High pressure will build in behind this system for later Wednesday
and Wednesday night ushering in drier and cooler conditions.
The break from the active weather will be short-lived however, as
deterministic models and ensembles support a clipper system
diving through Upper Midwest and Great Lakes Thursday. Consensus
takes the track of the low to our north, but strengthening warm
advection/isentropic ascent will bring a good chance for a quick
shot of mainly rain Thursday night - highest probabilities (60-70%)
north of Hwy 30. Can`t rule out a few flakes north of Hwy 20, but
the strength of the WAA should keep this mostly if not all rain.

Heading into the weekend we remain in active W/NW flow aloft and
will see periodic precipitation chances, as waves/clipper systems
are shuttled down in/near the region. We will likely continue to
see a roller coaster of temperatures - quick warming in the
warm advection followed by cooling in the wake of these systems.
Despite still some fairly large IQRs in NBM during this time they
are centered near seasonal normals.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 532 AM CDT Mon Mar 9 2026

VFR conditions will persist through 06z/10th. After 06z there is
a chance (20-30%) for patchy fog and stratus and lower
conditions of IFR/MVFR. LLWS will be the main concern until 14z
this morning, as W/SW winds aloft near 2kft agl of 40-50 kt
outpace the surface winds around 10 kt with occasional gusts
near 20 kt. After 14z, with mixing southerly surface winds
should gust with more frequency to around 20 kt. The winds will
become light this afternoon and evening, and variable at
KCID/KDBQ while remaining predominantly from the south at
KMLI/KBRL, as a frontal boundary sags into the region. Weak
convergence could bring some fog and stratus potential near the
boundary overnight, but low confidence on location/extent
combined with it being late in the TAF period precludes mention
at this time. In addition, a strengthening NE flow off Lake
Michigan could advect in some lower stratus at KDBQ and possibly
KMLI late in the period, but again confidence is too low to add
mention at this range.

&&

.CLIMATE...
Issued at 333 AM CDT Mon Mar 9 2026

Record High Temperatures:

March 9:
KBRL: 74 in 1986
KCID: 68 in 2021
KDBQ: 65 in 1977
KMLI: 71 in 2021

March 10:
KBRL: 76 in 1955
KMLI: 74 in 1955

&&

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

&&

$$

SHORT TERM...McClure
LONG TERM...McClure
AVIATION...McClure
CLIMATE...McClure