Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 300831
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
331 AM CDT SAT JUL 30 2016

.SYNOPSIS...
Issued at 330 AM CDT Sat Jul 30 2016

Weak upper low embedded in a broad trough still over the area
producing plenty of low stratus along with light to calm winds. A
band of showers and isolated thunderstorms was located across
southern Lake MI and on into western lower MI. Water vapor movie
loops showed a short wave moving eastward into western IA. 3 am
temperatures across the cwa were in the mid 60s to lower 70s.

&&

.SHORT TERM...(Today and Tonight)
ISSUED AT 330 AM CDT Sat Jul 30 2016

Today: Similar weather pattern as the past couple of days with
weak upper level low/trough over the area, combined with a short
wave arriving from the west. Operational models a bit more
aggressive with precipitation so have raised pops somewhat. The
better forcing and moisture look to be mainly in our northern and
eastern counties so will have pops in the 40-50 percent range.
Elsewhere 20-30 pops. There will be plenty of low stratus this
morning giving way to more sunshine this afternoon. This will push
maximum temperatures into the upper 70s to lower 80s, and increase
instability.

Precipitation: Isolated showers early this morning will increase
to scattered showers and thunderstorms later this morning and
afternoon, as the convective temperature is reached. Similar to
yesterday the showers and storms will be drifting slowly to the
west/southwest. With PWAT`s close to 1.50 inches heavy rainfall
will occur in the stronger storms, which may cause localized flash
flooding. However, not expecting this to be widespread. Deep layer
shear is very weak, but similar to the past several days a couple
of brief funnel clouds may form on any boundaries in the cwa.

Tonight: Models finally shift the upper trough/short wave quickly
into the OH Valley as heights begin to rise. Any lingering showers
or storms will have ended by late afternoon or early evening so
much of the night will be dry. Skies should be partly cloudy but
with light winds and lingering moisture there may be patchy or
areas of fog, for later shifts to add if needed. Lows will be in
the lower to mid 60s.

.LONG TERM...(Sunday through Friday)
ISSUED AT 330 AM CDT Sat Jul 30 2016

On Sunday, the Nam is an outlier among the synoptic models in
translating a more vigorous vort max into the area during the
afternoon hours, with convection developing across the south before
00Z. Will continue to favor the slower solutions and hold off pops
until later Sunday night. Southern counties look most favored for
organized storms, along the 850mb moisture convergence axis with
support from short wave energy along the periphery of the upper
ridge. The main issue will likely be localized heavy rain.

For Monday, expect the gradual warming trend to continue with
seasonal highs in the 80s. Storms will persist into the morning
hours, with potential for some redevelopment during the afternoon.
Of more concern is a somewhat consistent signal of late pointing
toward a potential MCS Monday night into early Tuesday which could
produce more locally heavy rain over portions of the forecast area.

Tuesday afternoon into Thursday, any convection is expected to be
isolated in nature as the region is impacted by a broad upper ridge.
Expect hot and very humid conditions, especially Wednesday and
Thursday, with potential for heat indices over 100 degrees. The most
extreme conditions are expected south of Interstate 80.

By Thursday night into Friday, a boundary is forecast to move
through the area, accompanied by somewhat cooler temperatures and
scattered showers and thunderstorms.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
ISSUED AT 1142 PM CDT Fri Jul 29 2016

Residual low level moisture and weak convergence should foster
stratus and fog overnight into mid morning Saturday, with
conditions lowering into mvfr and ifr with areas of lifr and
possibly vlifr. Anticipate conditions to gradually improve to
vfr during the afternoon. With weak convergence and upper low
in proximity can`t rule out some showers and possibly a storm,
especially with afternoon heating, but too difficult to pin down
favored location and timing thus left out any mention with 06z
tafs. Winds will generally be light northerly through the cycle.

&&

.DVN Watches/Warnings/Advisories...
IA...None.
IL...None.
MO...None.
&&

$$

SYNOPSIS...Haase
SHORT TERM...Haase
LONG TERM...RP Kinney
AVIATION...McClure



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