644
FXUS63 KDVN 102027
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
327 PM CDT Sun Aug 10 2025

.KEY MESSAGES...

- Several rounds of thunderstorms are forecast through Tuesday.
  Heavy rain is expected with storms now through Monday night.

- Flash flooding is the main concern through the next several
  days with a 25% chance of excessive rainfall west of the
  Mississippi River and a 25-50% chance east of the river. The
  strongest storms could produce torrential rainfall rates
  between 1-3" per hour and locally damaging winds.

- Widespread 1 to 4 inches of rain are possible through Monday
  with some areas receiving higher amounts.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 327 PM CDT Sun Aug 10 2025

A diffuse cold front stretched from east of Kansas City, MO to
near Centerville, IA to near Decorah to near Red Wing, MN. A
Mesoscale Convective Vortex (MCV) left over from this morning`s
storms in Nebraska, Kansas, and Missouri was centered near Des
Moines. The cold front is forecast to stall out over eastern
Iowa, southwest Wisconsin, and northern Missouri this evening
while the MCV advances east-northeastward across eastern Iowa.
Convergence along the front and enhanced forcing for ascent near
the MCV is expected to support another round of scattered
thunderstorms late this afternoon through tonight. Both the NAM
and RAP feature strengthening isentropic ascent to the east of
the front later tonight as a southwesterly low-level jet
develops over northern Illinois and southeast Wisconsin. This
will further aid thunderstorm development. Moisture transport
vectors suggest ample moisture for locally heavy rainfall. The
greatest risk for heavy rain will be this afternoon and evening.

Strong downburst wind gusts are possible with the thunderstorms
and may cause localized wind damage. The Storm Prediction
Center has areas east of the Mississippi River outlined in a
Marginal Risk of severe weather (1 out of 5 risk).

The front will remain over the region tonight through Monday
night. Southwesterly winds near the surface will replenish the
low-level moisture during this time. Several ripples in the mid-
and low-level flow will support additional chances of
thunderstorms through Monday night. Locally heavy rain will
remain possible with the strongest storms.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 327 PM CDT Sun Aug 10 2025

By Tuesday the front will begin to push eastward and take the
rain chances with it. Wednesday is shaping up drier as high
pressure builds into the region. Northwesterly winds will usher
in less humid air with dewpoints in the 60s. By Friday and
Saturday, the upper-level pattern will become favorable for
isolated to scattered showers and thunderstorms. Warm
temperatures with highs in the upper 80s to low 90s are forecast
by Saturday with dewpoints in the middle and upper 70s.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1257 PM CDT Sun Aug 10 2025

Winds are shifting to the S to SSW this afternoon as morning
storms have moved out. A few showers in the early afternoon are
possible at southeastern sites. Models suggest a line or two of
showers and storms developing this afternoon, more likely in the
southeast near KMLI/KBRL. Heavy rain from today may contribute
to fog formation overnight, but fog will be limited in areas of
broader low cloud coverage. Rain is unlikely overnight through
tomorrow morning and winds remain 5 kts or less, leaving MVFR
cigs the primary concern mid to late morning, especially in the
southeast.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Flood Watch until 7 PM CDT this evening for IAZ040>042-052>054-
     064>068-077-078-087>089-098-099.
IL...Flood Watch until 7 PM CDT this evening for ILZ001-002-007-009-
     015-016-024>026-034.
MO...Flood Watch until 7 PM CDT this evening for MOZ009-010.

&&

$$

SHORT TERM...Previous Fcter
LONG TERM...Previous Fcter
AVIATION...NWS