457
FXUS63 KDVN 191748
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1248 PM CDT Wed Jun 19 2024

...18z Aviation Update...

.KEY MESSAGES...

- Scattered thunderstorms today and not as hot

- Hotter again Friday and Saturday

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 410 AM CDT Wed Jun 19 2024

Today: Cold front just to the west of the forecast area was
producing a band of showers and thunderstorms from southwest IA
to northeast IA early this morning. This front will continue to
slowly move southeast across the entire forecast area as the day
progresses. This front getting a nudge to the southeast as low
pressure tracks from Lake Superior to James Bay. Scattered to
clusters of showers and storms should occur today, with the
higher chances 50-70 percent in our northwest, with lesser pops
to the southeast. This scenario will also continue into this
evening as the front begins stalling in far northern MO.

Forecast soundings indicate that shear and instability will be
even less than what was given me yesterday. As a result, SPC has
removed our area from the Marginal Risk that was in place.
However, any stronger storm could still produce gusty winds to
40 mph and heavy downpours with PWAT`s of 1.60 inches and storms
moving northeast at 25 mph.

There will be a nice temperature gradient across our area with
highs in the upper 70s at Independence, IA to 92 at Macomb, IL.

Tonight: The main area of scattered showers and storms will
remain roughly across our northwest half, as the front begins
returning northward as a warm front. Lows will range from the
mid 60s nw to the lower 70s se.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 410 AM CDT Wed Jun 19 2024

Thursday through Friday: With the warm front lifting north of
the forecast area, the main concentration of thunderstorms and
heavy rainfall will once again be in southern/central MN and WI.
(This additional rain will raise concerns for flooding later
this month especially on the Mississippi River as the water
flows downstream into our area. Stay tuned to updated river
forecasts).

As a result of the front well to our north, our temperatures
will turn hotter again with much of the area having highs in
the lower 90s. The NBM temperatures have shown a warm bias
lately and I have lowered these readings a couple of degrees.

Little change in forecast reasoning from yesterday:

This weekend: Global models similar in developing a stronger
trough and surface low tracking from the northern Plains to the
northern Great Lakes region. This sweeps a cold front across our
forecast area Saturday afternoon and night, which may offer the
potential for strong to severe storms. This is a pattern change
as this deepening trough into the eastern United States breaks
down the persistent heat dome. Highs in the lower to mid 90s on
Saturday and then in the 80s on Sunday.

Early next week: Another pattern change to a heat dome building
in the southern Plains with hot weather returning to our area
with highs again in the lower 90s. Pattern recognition suggests
MCS`s riding the edge of the heat dome will impact near or
across the forecast area. Stay tuned!

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1242 PM CDT Wed Jun 19 2024

As a northeast-to-southwest oriented front sags acrs the area in
from the west, some MVFR to low VFR cumulus will continue to the
east of the front and spread eastward increasing into IL this
evening. The watch will be on for pre-frontal isolated to sctrd
showers and thunderstorms that may pass by in the VCNTY of most
of the TAF sites this afternoon into the evening. A few may be
strong with gusty variable winds and temporary reduced VSBYs
down to under 2 miles as they pass by with heavy rain and winds.
A rather slow passage of the front will bring about a sfc wind
veering to the northwest and then eventually north to northeast
through the TAF sites later this afternoon and evening. Some
uncertainty with regards with post-frontal low MVFR to IFR
clouds late tonight into Thu morning that some models want to
do. But may trend with lower MVFR early Thu morning for now at
most sites except BRL.


&&

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

&&

$$

SHORT TERM...Haase
LONG TERM...Haase
AVIATION...12