334
FXUS63 KDVN 140707
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
207 AM CDT Sun Jul 14 2024

.KEY MESSAGES...

- The heat continues for today and Monday with peak heat indices
between 100 to 110 F...slightly offset by winds of 10 to 20 mph.

- Strong isolated thunderstorms are possible this evening and
  overnight again, with low confidence on them occurring.
  Another organized round of heavy rain and severe weather is
  forecast Monday PM into Tuesday as a strong cold front
  arrives.

- Moderate to major river flooding continues on the Mississippi
  River with most sites crested or cresting in the coming days.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 204 AM CDT Sun Jul 14 2024

Our local area was brushed by strong convection late in the evening,
affecting Stephenson co with heavy rain and gusty winds, while areas
just east were greatly impacted by torrential rains.  This ring of
fire zone just to the northeast is forecast to be active again
today, but could be a bit farther northeast than the past 24 hours.

At the start of today, area wide, some very high based showers
and storms could be ongoing on top of the LLJ position aimed
into Wisconsin. This could bring some scattered activity for a
few hours, with limited impacts to brief downpours. Otherwise,
we`re closely watching the convective cluster moving through the
Twin Cities this morning, as that could again brush the
northeastern counties with stronger thunderstorms.

Otherwise today will be hot and breezy!  Like yesterday, a moist air
mass, combined with peak crop evapotranspiration will help dew
points rise to the 72 to 77 range, and with temperatures in the 90
to 94 range, heat indices will reach 100 to 105 in many areas.
A heat advisory will be issued for all counties, from 1 PM to 8
PM.

Tonight, a low chance exists that strong to severe storms can again
brush our northeast is there, but most models continue to keep the
action well northeast of our CWA. CAPE over 4000 will ensure any
activity will be strong of it happens.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 204 AM CDT Sun Jul 14 2024

The hot weather will continue on Monday with chances for scattered
showers and storms as a cold front gradually drops in from the
north. Models continue to show a strong EML, but the frontal
position could serve to erode that with time, especially after dark.
The ample CAPE over 4000 J/KG would support strong storms, as would
the increasing shear from the westerly flow aloft. For now, pops are
in the 40-60% range by Monday night into Tuesday morning.

The main threat for Monday night`s storms will be damaging winds,
but another threat is heavy rainfall over 2 inches. We`ll advertise
some heavy rain threat through the night Monday night, as the front
timing has slowed, with less northwest flow establishing itself
until later Tuesday.

Tuesday night through the weekend ahead continue to appear cooler
than normal, and extremely pleasant. Overnight lows well into the
50s are forecast on several nights, giving our air conditioning a
bit of a break.

ERVIN

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1240 AM CDT Sun Jul 14 2024

An organized thunderstorm cluster near the Twin Cities as of
06Z will likely track into southwest Wisconsin by the pre-dawn
hours. This will possibly impact DBQ near/shortly after
daybreak (50 percent chance) while reaching MLI is a lesser
chance (20%). Otherwise through early morning, patchy MVFR
ceilings are possible mainly toward DBQ.

South-southwest winds this afternoon will have gusts that
should occasionally reach 20 kt and probably regularly exceed at
MLI and BRL. As for thunderstorms this afternoon and evening,
confidence is low in whether they will occur, but if they
happen they should be minimal coverage (20-30%). So not enough
confidence to include mention in the TAFs at this point.

&&

.HYDROLOGY...
Issued at 938 AM CDT Sat Jul 13 2024

The crest on the Mississippi River is now between Keithsburg,
IL and Gladstone, IL (L/D 18). Upstream of New Boston (L/D 17)
river levels continue to fall. New Boston and Keithsburg are
just starting to show signs of falling. As the broad crest
continues to attenuate, areas from Gladstone downstream to
Gregory Landing should begin a very broad crest over the next
day or two.

Tributary Rivers:

On the lower Cedar River near Conesville, IA, minor flooding
continues. Over the next 24 to 36 hours the flooding is forecast
to end.

The lower Wapsipinicon River near Dewitt, IA will remain in
moderate flood through mid-day Sunday before falling into minor
flood. A fairly rapid drop in water levels will commence Sunday
afternoon and night as backwater effects from the Mississippi
River decrease.

Minor flooding continues on the lower Iowa River at Oakville due
to backwater effects from the Mississippi. With the broad crest
on the Mississippi now just south of Keithsburg, IL, water
levels on the lower Iowa River will slowly fall to and then
remain around flood stage over the next four days.

&&

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

&&

$$

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