Flash Flood Warning 7, NWS Des Moines, IA

337 
WGUS73 KDMX 071114
FFSDMX

Flash Flood Statement
National Weather Service Des Moines IA
614 AM CDT Sun Aug 7 2022

IAC033-081-189-195-071415-
/O.CON.KDMX.FF.W.0007.000000T0000Z-220807T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cerro Gordo IA-Hancock IA-Winnebago IA-Worth IA-
614 AM CDT Sun Aug 7 2022

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 AM CDT THIS 
MORNING FOR NORTHERN CERRO GORDO, NORTHERN HANCOCK, WINNEBAGO AND 
WORTH COUNTIES...

At 614 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 4 and 8 inches of rain have 
fallen across southern portions of Worth and Winnebago counties. 
Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Forest City, Northwood, Lake Mills, Manly, Rice Lake, Buffalo 
  Center, Thompson, Plymouth, Fertile, Leland, Kensett, Grafton, 
  Crystal Lake, Woden, Hanlontown, Rake, Joice, Rock Falls, 
  Scarville and Bolan.

This includes the following highways...
	Interstate 35 between mile markers 200 and 218.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4350 9397 4350 9302 4320 9302 4323 9397

FLASH FLOOD...RADAR INDICATED

$$

Donavon

Area Forecast Discussion
National Weather Service Des Moines IA
308 AM CDT Sun Aug 7 2022

.DISCUSSION.../Today through Saturday/
Issued at 132 AM CDT Sun Aug 7 2022

Key Messages:

- Heavy rain threat continues across northern Iowa into the early
  morning hours.
- Hot again central/south today. More showers and storms likely
  especially by late afternoon and evening.

Convection and heavy rain threat is ongoing over northern Iowa as we
head through the heart of the overnight hours. Initial round of
activity last afternoon and evening was mainly focused
along/north of a quasi-stationary cold front and low level CAPE
axis. Redevelopment has now occurred along the nose of a
strengthening LLJ and corridor of enhanced moisture convergence.
The atmosphere remains juiced in this area with surface Td in the
low 70s beneath a plume of Pacific monsoonal moisture cresting the
top of an upper ridge. GOES-R has sampled PW values as high as
2.3" in northern Iowa tonight. Multiple round of convection with
embedded intense rainfall rates will lead to pockets of heavy
rainfall by daybreak, likely nearing 4-6+" in some locales. Dry
soils and mature crops will mitigate a share of the flash flood
threat outside of urban areas. Some flood concern may develop if
higher end totals are realized. Convection percolates further
south into central Iowa as toward the morning hours, but should
fade away and move east as the low level jet begins to taper off.

Frontal boundary is very lethargic today and makes only meager
southward progression. Hot temps once again south of the boundary
and guidance continues to trend upward. Forecast was warmed
closer to the mean of model guidance however the guidance spread
is significant, especially over central Iowa, and likely due to
uncertainties with cloud cover and convective trends. Thus opted
to leave the heat advisory alone for now. Synoptic support for QG
ascent remains as upper shortwave trough holds west over the
northern Plains, which may spark additional iso/sct convection
through the day. Pinpointing timing/location/coverage is difficult
at this point as hi-res models struggle to resolve mesoscale
details in the wake of overnight convection, but most models do
agree on a peak in coverage again late this afternoon and evening
central and north. A few more intense updrafts are possible with
severe wind gusts and heavy rain the primary threat.

Upper shortwave finally kicks east Monday and shoves the frontal
boundary south of the area. Some precip chances linger into Monday
before the forecast dries out again through the rest of the day.
Tuesday looks quite nice as a Canadian surface ridge axis drops
south through the region. Expect highs in the low 80s and much
more comfortable humidity. The heat reprieve is short lived as the
upper ridge builds again out west and migrates east through the
end of the week. Highs make a return again to near 90 Wednesday
and high probability of above normal temperatures lasting into
next weekend, especially for the western half of the state.

&&

.AVIATION.../For the 06Z TAFS through 06Z Sunday night/
Issued at 1141 PM CDT Sat Aug 6 2022

Rounds of storms north affecting mainly KMCW and KALO with some
potential at KFOD through 16z with another period from 20z
through aft 00z. MVFR/IFR cigs possible at times with stronger
convection. Though some uncertainty in timing, some storms may see
gusts 35-40kts as well with 3/4 to 2sm vsby through 13z. Details
for convection aft 18z more uncertain and better handled by next
update. /rev

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 10 AM CDT this morning for IAZ004>007-015>017.

Heat Advisory from noon today to 8 PM CDT this evening for
IAZ070>072-081>086-092>097.

&&

DISCUSSION...Martin
AVIATION...REV

Hazardous Weather Outlook
National Weather Service Des Moines IA
904 PM CDT Sat Aug 6 2022

IAZ023>028-033>039-044>050-057>062-073>075-080215-
Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun-
Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-
Boone-Story-Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-
Poweshiek-Warren-Marion-Mahaska-
904 PM CDT Sat Aug 6 2022

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

Thunderstorms are possible north tonight. An isolated severe
storm with 60 mph winds may occur. Locally heavy rainfall is
possible, mainly north of Highway 30.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Thunderstorm chances will continue Sunday through Monday morning.
The overall threat for severe weather is low but locally heavy
rainfall is possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is possible later tonight.

IAZ004>007-015>017-080215-
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
904 PM CDT Sat Aug 6 2022

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

A Flood Watch is in effect for tonight through Sunday morning.
Please refer to the National Weather Service website at
weather.gov/desmoines for further details.

Thunderstorms are possible tonight. An isolated severe storm with
60 mph winds may occur.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Thunderstorm chances will continue Sunday through Monday morning.
The overall threat for severe weather is low but locally heavy
rainfall is possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is possible later tonight.

IAZ070>072-081>086-092>097-080215-
Cass-Adair-Madison-Adams-Union-Clarke-Lucas-Monroe-Wapello-Taylor-
Ringgold-Decatur-Wayne-Appanoose-Davis-
904 PM CDT Sat Aug 6 2022

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

A Heat Advisory is in effect for the area Sunday afternoon.
Please refer to the National Weather Service website at
weather.gov/desmoines for further details.

A few scattered thunderstorms are possible tonight but are
expected to remain further north. Severe weather threat is low but
locally heavy rainfall is possible.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Thunderstorm chances will continue Sunday through Monday morning.
The overall threat for severe weather is low but locally heavy
rainfall remains possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated today.

Dodson

Special Weather Statement
National Weather Service Des Moines IA
1240 AM CDT Sun Aug 7 2022

IAZ017-026>028-070645-
Bremer IA-Cerro Gordo IA-Franklin IA-Butler IA-
1240 AM CDT Sun Aug 7 2022

...A strong thunderstorm will impact portions of northwestern Bremer,
northern Franklin, northern Butler and southern Cerro Gordo Counties
through 145 AM CDT...

At 1240 AM CDT, Doppler radar was tracking a strong thunderstorm near
Rockwell, or 14 miles south of Mason City, moving east at 25 mph.

HAZARD...Very heavy rainfall has occurred with these storms with
         some areas receiving over 3 inches of rain already. An
         additional 1-2 inches is possible with these storms. Winds
         in excess of 30 mph are also possible.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Ponding of ponding of water on roadways,
         low visibilities, and rises in small streams and creeks.

Locations impacted include...
  Greene.

This includes Interstate 35 between mile markers 174 and 190.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 4275 9245 4286 9350 4287 9350 4309 9343
      4306 9302 4291 9302 4291 9243
TIME...MOT...LOC 0540Z 275DEG 21KT 4295 9311

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...30 MPH

Donavon

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
114 AM CDT SUN AUG 7 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0100 AM     HEAVY RAIN       GARNER                  43.10N 93.60W
08/07/2022  M3.20 INCH       HANCOCK            IA   TRAINED SPOTTER

&&

RD