Alert archive / Illinois / Special Weather Statements in 2022

Special Weather Statement, NWS Quad Cities, IA

August 3, 2022Scott County, Iowa; Mercer County, Rock Island County, Illinois

NWS Quad Cities, IA issued this special weather statement at Aug 3, 2022, 9:13 AM CDT for Scott County, Iowa; Mercer County, Rock Island County, Illinois. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 3, 2022, 9:13 AM CDT (14:13 UTC)
Expired
Aug 3, 2022, 9:45 AM CDT
In force
32 min
Issued by
NWS Quad Cities, IA
Hail
0.50 in
Wind
40

Counties Scott County, IA, Mercer County, IL, Rock Island County, IL

The radar

The Quad Cities radar (KDVN), 10 km from the middle of the area, began a volume at 14:14 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 2.2 hours before the alert went out and 6 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2022-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2069 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2022-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 152 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
2069 J/kg
Mixed-layer CIN
-232 J/kg
Mixed-layer LCL
1408 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
152 m²/s²
0-3 km storm-relative helicity
145 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Quad Cities, IA wrote its last area forecast discussion before this special weather statement went out at Aug 3, 4:44 AM CDT, 4 hours 29 minutes earlier.

Area forecast discussion, Aug 3, 4:44 AM CDT, 4 hours 29 minutes before
Area Forecast Discussion
National Weather Service Quad Cities IA IL
444 AM CDT Wed Aug 3 2022

...AVIATION UPDATE...

.SYNOPSIS...
Issued at 252 AM CDT Wed Aug 3 2022

Strong southwesterly flow aloft has set up over the area, ahead of
the incoming system. With this, we have started to see moisture
increase throughout the area. Thus, we are looking at quite a muggy
start to the day, with much of the area showing dewpoints in the low
to mid 70s! Temperatures are not much higher than that. Thus, this
is what we consider "air that you can wear." We have stayed dry
through the night, but with the approaching cold front and the
current state of the atmosphere, we will end up seeing precipitation
by mid morning. While heat headlines are not expected today, very
warm and humid weather will still result. In the extended, above
normal temperatures still remain, with a more active pattern ahead
of us.

&&

.SHORT TERM...(Today and Tonight)
ISSUED AT 252 AM CDT Wed Aug 3 2022

The main story for the short term will be the weak surface low that
drags a cold front through the area today. Precipitation timing has
been pushed back a little bit since last forecast, with the current
thinking being the cold front pushing into the area by mid morning.
Showers and embedded storms are expected to rapidly develop in
central IA after sunrise and move into our area. At this time, we
are not expecting much on the severe side of things, but a stray
strong to severe storm cannot be ruled out. Best chance to see any
strong to severe storms will be later in the day, when we get some
heating ahead of the front. Generally, the areas to watch will be
east of the Mississippi River in the afternoon. The Storm Prediction
Center has highlighted these areas in a Marginal Risk for Severe
Weather, with a Slight Risk for the far southeast. Primary hazards
are looking to be damaging winds and isolated large hail.

With the threat of showers and storms through the day, that means
that we will be mostly socked in with clouds. Thus, we have gone
ahead and lowered temperatures even more. As I mentioned yesterday,
this "cooler trend" continues. While we will still be in the upper
80s and very humid, heat index values are progged to be in the 90s.
Thus, heat headlines are no longer expected today.

Tonight, post frontal airmass kicks in as high pressure slowly makes
its way in from the north. Humidity isn't expected to drop much
until around midnight local time. Once the dew points go down, we
will start to see the temperatures drop as well. Temperatures
overnight will range from the low 60s in the northwest to near 70
in the southeast. Most of the area will remain dry, with the best
chance to see any precipitation in our far southeast. Chances are
higher that the southeast will stay dry overnight.

.LONG TERM...(Thursday through Tuesday)
ISSUED AT 252 AM CDT Wed Aug 3 2022

Key Messages:

1.  Heat returns in the long term as ridging builds into the area.
2.  Next chance for any pops is late in the weekend to start the
week.

Discussion:

Little unchanged in the long term.  Ridging builds into the area,
leading to warmer temps across the area. High temps will climb from
the 80s into the 90s for the weekend as the ridge builds in.
Saturday looks like the hottest days as temps in the low to upper
90s are forecast across the area.  As is typical with heat, do we
get that warm and mix down drier air or do we stay cooler and the
Tds make the heat indices approach Heat Adv levels.  At this time,
it is difficult to tell which wins out.  Regardless, its going to be
hot through the weekend.

Towards the end of the weekend, models still agree on a better wave
passing north of the area and bringing cold front into the area.
Chances for storms return for Sunday into Monday.  Boundary looks to
stall near the area and could lead to chances for pops for a day or
so.

&&

.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
ISSUED AT 434 AM CDT Wed Aug 3 2022

VFR conditions will last through mid morning. Around 15Z and
beyond, we can see MVFR conditions from the showers and storms
that move through. Heavy rain and thunderstorms will likely drop
cigs and vis, especially after 18Z. After 00Z Thursday, we will
start to see the showers and storms move out, leaving us in
northwest winds and clearing skies. VFR conditions will last
through the night and into tomorrow.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

SYNOPSIS...Gunkel
SHORT TERM...Gunkel
LONG TERM...Gibbs
AVIATION...Gunkel
Hazardous weather outlook, Aug 3, 4:04 AM CDT, 5 hours 9 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
404 AM CDT Wed Aug 3 2022

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-040915-
Buchanan-Delaware-Dubuque-Benton-Linn-Jones-Jackson-Iowa-Johnson-
Cedar-Clinton-Muscatine-Scott-Keokuk-Washington-Louisa-Jefferson-
Henry IA-Des Moines-Van Buren-Lee-Jo Daviess-Stephenson-Carroll-
Whiteside-Rock Island-Henry IL-Bureau-Putnam-Mercer-Henderson-
Warren-Hancock-McDonough-Scotland-Clark-
404 AM CDT Wed Aug 3 2022

This Hazardous Weather Outlook is for portions of north central
Illinois...northwest Illinois...west central Illinois...east
central Iowa...northeast Iowa...southeast Iowa and northeast
Missouri.

.DAY ONE...TODAY AND TONIGHT

Threat for thunderstorms today, where some may be strong to
severe in the afternoon. Best chances to see strong to severe
storms will be east of the Mississippi River. The Storm
Prediction Center has issued a Slight Risk for severe weather in
our far southeast, with a Marginal Risk for those along and east
of the Mississippi River. Primary hazards will be damaging winds
and isolated large hail.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

Next chance for possible heat headlines will be over the weekend,
with temperatures over 90 and increasing humidity once again.
There is also a chance for thunderstorms Sunday and Monday. The
chance for severe weather appears low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this afternoon and evening.

In the hours before

Special weather statement, Aug 3, 9:13 AM CDT, 0 minutes before
Special Weather Statement
National Weather Service Quad Cities IA/IL
913 AM CDT Wed Aug 3 2022

IAZ066>068-078-089-ILZ007-009-015-016-024-031445-
Mercer IL-Whiteside IL-Carroll IL-Rock Island IL-Henry IL-Scott IA-
Clinton IA-Des Moines IA-Muscatine IA-Louisa IA-
913 AM CDT Wed Aug 3 2022

...Strong thunderstorms will impact portions of Rock Island, central
Mercer, northwestern Whiteside, northwestern Henry, south central
Carroll, northeastern Des Moines, southeastern Louisa, Scott, east
central Muscatine and southeastern Clinton Counties through 945 AM
CDT...

At 912 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Donahue to near New Boston. Movement was
northeast at 35 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Davenport, Moline, Rock Island, Bettendorf, Clinton, East Moline,
Aledo, Silvis, Eldridge, Milan, Colona, Camanche, Le Claire, Coal
Valley, Fulton, Hampton, Port Byron, Blue Grass, Buffalo and
Andalusia.

This includes the following highways...
 Interstate 74 in Iowa between mile markers 1 and 5.
 Interstate 80 in Iowa between mile markers 287 and 306.
 Interstate 80 in Illinois between mile markers 1 and 6.
 Interstate 74 in Illinois between mile markers 1 and 11.
 Interstate 88 near mile marker 1.
 Interstate 280 between mile markers 1 and 18.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4194 9007 4119 9052 4107 9105 4170 9068
TIME...MOT...LOC 1412Z 247DEG 32KT 4166 9064 4117 9093

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

DC

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 3, 9:45 AM CDTSpecial Weather StatementDVNBenton, Iowa, Linn30 min
Aug 3, 10:02 AM CDTSpecial Weather StatementDVNDes Moines28 min
Aug 3, 10:19 AM CDTSevere Thunderstorm WarningDVNBenton, Buchanan, Delaware, Jones, Linn26 min
Aug 3, 10:46 AM CDTSpecial Weather StatementDVNBuchanan, Cedar, Delaware, Johnson, Jones, Linn44 min
Aug 3, 11:02 AM CDTSevere Thunderstorm WarningDVNDelaware, Dubuque, Jones28 min
Aug 3, 11:28 AM CDTSevere Thunderstorm WarningDVNDelaware, Dubuque18 min
Aug 3, 6:10 PM CDTSpecial Weather StatementDVNDubuque35 min
Aug 3, 9:44 AM CDTSpecial Weather StatementDVNWhiteside31 min
Aug 3, 12:20 PM CDTSpecial Weather StatementDVNMercer25 min

Nearby

Special Weather Statements in Illinois, 2022Special Weather Statements in Iowa, 2022Every special weather statement in 2022

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.