Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 250821
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
321 AM CDT MON JUL 25 2016

.SYNOPSIS...
Issued at 319 AM CDT Mon Jul 25 2016

The latest SFC analysis was indicating a frontal system pushing
south and east of the local area but slowing/stalling along the way
acrs southeastern KS, up through central and northeastern IL and
into lower MI. A ridge of high pressure was dumping south acrs the
northwestern high plains. Aloft, the current water vapor loop was
indicating a short wave trof pushing eastward acrs the western GRT
LKS, with wake upper ridging starting to bulge up the northwestern
plains.

&&

.SHORT TERM...(Today and Tonight)
ISSUED AT 319 AM CDT Mon Jul 25 2016

Today...Some debris mid and high clouds will continue to stream up
acrs portions of the CWA through mid morning off convective systems
acrs KS and MO, but then expect upstream both sfc and upper ridging
to build from acrs the MO RVR Valley and acrs IA for a clear off.
The CU rule suggests some cumulus development of sctrd coverage
moving out of WI and acrs portions of NW IL this afternoon, but
nothing to ruin sunny sky wording acrs most of the CWA. Northwest
winds of 10 to 15 mph in in-building sfc high pressure gradient. A
post frontal day for less humid and not as hot conditions, but still
expect enough mixing in lingering warm thermal profiles to drive
widespread high temps into the mid 80s, and the normal warm bias
locations pushing the upper 80s. The Hwy 20 corridor may be more in
the way of low to mid 80s. Dry-down mixing and advection from the
northwest should help keep a lid on sfc DPTS, but crop/plant
evapotranspiration will battle this process some and keep values up
at least in the mid 60s.

Tonight...most of the 00z run model solutions settle incoming sfc
anticyclone center right overhead for sfc wind decouple to light and
variable or calm overnight. With expected clear to mainly clear
skies and lingering sfc moisture, will add at least patchy fog to
the grids late tonight. There looks to be the potential for some
dense fog banks in areas before dawn Tue morning, but will have to
see how SFC DPTs respond and what cross-over temps occur this
afternoon to further assess. Will go with widespread lows in the low
to mid 60s.    ..12..

.LONG TERM...(Tuesday through next Sunday)
ISSUED AT 319 AM CDT Mon Jul 25 2016

High pressure remains in control through Tuesday night, then a
transition toward a more active pattern returns thunderststorm
chances, especially for the Wed through Fri period. Hot and very
humid weather is not likely to make a return, with temperatures
likely near or even below late July normals through the week.

Tuesday: Surface high pressure, initially overhead, will provide
another day of relatively low humidity, light winds and nearly full
sunshine boosting highs into the lower to mid 80s.

Wednesday through Friday: A building ridge over the western U.S.
west will keep the very warm temperatures confined well west of the
local area. The resulting NW upper level flow with embedded
shortwaves and returning moisture will set up a favorable setup for
periodic thunderstorm chances throughout. However, unlike the past
several days, both precipitable water and MUCAPE values, as shown by
at least the GFS and SREF, should not approach extreme values. Thus,
conditions will be much less favorable for flash flooding and severe
weather. Consensus has highs in the lower to mid 80s with overnight
lows in the 60s.

Next weekend: The ECMWF, and to a less extent the GFS, begin to
shift the western upper ridge eastward, and also suggest a period
without an active low level boundary in the local area. This would
result in a lower potential for thunderstorms, along with warmer
temperatures.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
ISSUED AT 1116 PM CDT Sun Jul 24 2016

The cold front has cleared the area, shifting the wind to the
northwest and bringing a noticeable drop in both the temperature
and humidity. VFR CIGS will linger at area TAF sites through
tonight, giving way to clear skies Monday morning.

&&

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

$$

SYNOPSIS...12
SHORT TERM...12
LONG TERM...Sheets
AVIATION...DMD



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