927
FXUS63 KDVN 010742
AFDDVN
Area Forecast Discussion
National Weather Service Quad Cities IA IL
242 AM CDT Wed Jul 1 2026
.KEY MESSAGES...
- Extreme Heat Warning continues through Thursday evening for
much of the area with ongoing prolonged period of hot and
very humid conditions. Daily peak heat index values of 100 to
110 and nighttime low temperatures only dropping into the mid
to upper 70s.
- Humid conditions will continues into the holiday weekend.
Cloud cover and slowly increasing storm chances will help to
lower ambient temperatures. Storm chances will increase from
the west and north into the weekend. Some storms may be strong
to severe as well as have the potential to produce locally
heavy rainfall.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 240 AM CDT Wed Jul 1 2026
No adjustments made to the ongoing heat headlines for now. Stout
upper ridge and EML centered from the lower MS RVR Valley to the
central Atlantic is keeping the ring of fire pattern close by from
the deep southwest plains, the MO RVR VAlley and ringing around the
northern half of the GRT LKS. Main fcst concern for the day if any
convection can bleed into the CWA from the west or north, or develop
in our area. Looking at the thermal profiles and lingering ridge
placement, it`s more likley most of the CWA will stay dry through
12z Thu as opposed to have storms blowing through it. BUt there is
another nice nocturnal LLVL convergence swath happening again
tonight acrs the eastern SD/NE border region and extending just
south of the IA/MN border into southern WI. There is a chance that
some of this activity may make it down into the northern cWA along
the Hwy 20 corridor or even pushing Hwy 30 if they manage some cool
pool assistance. Will have to account for this potential with at
least some low to moderate CHC POPs in the north mainly after
midnight and into Thu morning before they start to decay diurnally.
If some mature storms can make it into the north, damaging winds
would be the primary threat as well as locally heavy rain.
As for temps today, little in the way of airmass change and expect
similar highs as yesterday with a lot of lower 90s and a few spots
approaching the mid 90s. Wednesday night lows
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 240 AM CDT Wed Jul 1 2026
Thursday...This is the period and into Friday where the model
ensembles suggest wave and jet energy continue to suppress the
amplitude of the southeast ride and allow the flattening and
southeastward adjustment of the main storm track acrs the central
plains into the GRT LKS. May have to account for some lingering
storms or debris in the north Thu morning, while further south
things heat up again warranting the Extreme Heat Warning extension
in those areas through Thu evening. With the southeastward
adjustment of the mass fields, will have to watch the new
convergence zone shifted more acrs central IA for convective
initiation Thu afternoon and evening with any short wave or MCV
arrival in the flow aloft. Even with marginal looking shear profiles
currently that far out, there should be very high MUCAPE fields of 3-
4K J/kg to fuel strong convection. Will have to watch for an
isolated storm in the afternoon mainly in the west, with better
chances locally coming mid Thu evening and into the overnight period
as upstream convective development acrs central IA propagates
eastward potentially as an MCS. Damaging winds, heavy rainfall and
possibly some hail would be the concerns Thursday and Thursday night.
Friday through Tuesday...Boundaries and cloud cover left over from
the Thursday night storms will help to hold down temperatures and
also provide boundaries for diurnal convection Friday afternoon that
will continue into Friday night.
Starting Friday, rain chances will increase to 30-50% but not all
areas will see rain.
Saturday through Tuesday Assessment...a certainty (>95%) that humid
conditions will continue. Low (20-30%) confidence on storm timing
and areal coverage.
Another disturbance moving through the Midwest Saturday and Saturday
night currently looks to have the better chances to produce rain.
This may or may not be in the form of an organized storm complex.
Right now, the model consensus has rain chances at 30-55% with the
better chances along/north of I-80.
Starting Sunday, there are additional upper level disturbances/waves
progged to move through the area each day. However, there are timing
differences. The main message is that while there are rain chances
for each day, not everyone will see rain. Additionally, areal
coverage of any precip is low at 15 to 25 percent.
&&
.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1240 AM CDT Wed Jul 1 2026
Generally a VFR TAF fcst as long as the storms stay west and
north of the TAF sites, which the majority of CAMs and
deterministics suggest. But they may get into the VCNTY of DBQ
and possibly CID toward the end of the TAF cycle. Otherwise,
don`t expect MVFR BKN CU to develop acrs the CID and DBQ sites
like yesterday, although there still may be some SCT coverage.
South to southwesterly sfc winds to continue but may not be as
quite gusty on Wed as the past few days. With the lighter winds
currently ongoing overnight, have added back the LLVL wind shear
with southwesterly 2K FT AGL LLJ of 35-40 KTs into Wed morning.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Extreme Heat Warning until 10 PM CDT this evening for
IAZ040>042-051>054.
Extreme Heat Warning until 10 PM CDT Thursday for IAZ063>068-
076>078-087>089-098-099.
IL...Extreme Heat Warning until 10 PM CDT this evening for ILZ001-
002-007.
Extreme Heat Warning until 10 PM CDT Thursday for ILZ009-
015>018-024>026-034-035.
MO...Extreme Heat Warning until 10 PM CDT Thursday for MOZ009-010.
&&
$$
SHORT TERM...12
LONG TERM...12/08
AVIATION...12
NWS DVN Office Area Forecast Discussion