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FXUS63 KDVN 261753
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1253 PM CDT Wed Jun 26 2024

.KEY MESSAGES...

- Rain ending this morning with north winds ushering in much
  less humid air

- Heavy rain with showers and thunderstorms for early Friday
  into Saturday morning, some storms possibly severe Friday PM

- Storm chances again for Monday into Tuesday

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 350 AM CDT Wed Jun 26 2024

Showers will come to an end this morning as a cold front moves
well southeast of the area and a much less humid air mass builds
into the area from the north. Skies will become mostly sunny by
mid afternoon as temperatures reach into the lower to middle
80s. Winds will increase from the north at 10 to 20 MPH by late
morning with dew points dropping into the mid 50s to lower 60s.

Tonight, high pressure will be over the area bringing clear
skies and light winds to the area. It will be a good night to
open the windows, as overnight lows drop into the upper 50s to
low 60s.

Thursday will be a pleasant day with mostly sunny skies and
light winds. Highs will be in the upper 70s to low 80s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Issued at 350 AM CDT Wed Jun 26 2024

Thursday night through early Tuesday, the global models suggest
a rather strong zonal flow across the northern United States
which will keep the heat and humidity to our south. Two systems
will track across MN and WI during this period. The first one on
Friday will bring the possibility of heavy rains and severe
storms to the area once again. The second one currently expected
late Monday into Tuesday will bring rain chances along with
heat and humidity, with lower 90s for parts of the area. The SPC
has a Slight Risk, level 2 of 5, for the western 2/3 of the CWA
with a Marginal Risk, level 1 of 5, for our NW IL counties for
severe storms. At this time, hail, strong winds, and tornadoes
are all possible. It currently looks as though the focus will be
more to our southwest for Friday afternoon, with storms nearer
the cold front. Early Friday morning through midday, shower and
storms will be moving through which appear to be non-severe,
however could bring the possibility for heavy rainfall. WPC has
the entire area in a Slight Risk (level 2 of 4) for excessive
rainfall for Friday am into Saturday, with rainfall totals of 1
to 2 inches across the southern two thirds of the area. Another
round of storms is expected to move into the local area in the
evening and overnight timeframe, which may be severe. Both, the
severe and heavy rain potentials will be better refined in later
forecasts. The heavy rain risk has better confidence, and thus
more concern as to how it will affect the ongoing flooding
across the area. This will need to be watched closely.

Things quiet down for the weekend with pleasant temperatures as
high pressure moved through the area. Then, on the back side of
the high, return southerly flow will bring warmer and more
humid air back into the region along with rain chances, mainly
for later on Monday and into Tuesday.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1238 PM CDT Wed Jun 26 2024

High pressure is forecast to move across the area through the
TAF period resulting in VFR conditions. Clouds will begin to
build into the area late in the period ahead of a storm system
that is approaching the area from the west. Northerly winds will
be gusty this afternoon but decrease to around 5 knots after 00
UTC.

&&

.HYDROLOGY...
Issued at 1207 PM CDT Wed Jun 26 2024

Changes...

Flood warnings have been issued for the Mississippi River from
Keokuk, IA down through Gregory Landing, MO. The flood warning
for Gladstone, IL (L/D 18) has been raised to the major
category.

Flood warnings have been issued for the Cedar River for Cedar
Bluff and Conesville, IA.

Flood warnings have been issued for the Iowa River from Wapello
to Oakville, IA.

Discussion...

The Mississippi continues to rise with multiple locations
expected to reach flood stage by Friday. The flood crest is still
north of La Crosse, WI so much of the Mississippi will likely
remain above flood stage through the middle of July. Crests on
the Mississippi north of L/D 15 look to occur around the Forth
of July. South of L/D 15 crests will occur after the Forth of
July.

There is a high to very high probability that the Mississippi
will reach major flood stage before cresting from L/D 15 down
through L/D 17 in the July 3-10 time frame.

On the Cedar River the Crest is currently located in the Cedar
Falls area with crests occurring in Vinton, Palo and Cedar
Rapids areas in the Friday to Saturday time frame.

Water from the Cedar River will bring the lower Iowa River above
flood stage downstream from the confluence with the Cedar River.
Right now the Iowa River at Columbus Junction is not forecast to
reach flood stage. That may change depending upon where and how
much rainfall occurs late Thursday night into Friday night.

More rainfall is expected Thursday night through Saturday which
will have the potential to be heavy. This rainfall is not
included in the current river forecasts. As such, one should
expect changes to the crest forecasts based on the forecast QPF.

Outlook...

The overall weather pattern looks to remain quite active through
the Forth of July and potentially into the middle of July. The
MJO which has been weak to non-existent for much of June is
forecast to strengthen over the next 10 days and is forecast to
move from phase 2 to phase 4 over the next two weeks. Phase 3
and 4 of the MJO climatologically correlates to above normal
rainfall for the upper Midwest and Mid-Mississippi Valley.
Indeed the Climate Prediction Center has a 40-50 percent
probability of above normal precipitation July 3-9.

&&

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

&&

$$

SHORT TERM...14
LONG TERM...14
AVIATION...Cousins
HYDROLOGY...08