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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
1148 PM CDT sun Jul 27 2014

Short term...(this evening through monday)
issued at 314 PM CDT sun Jul 27 2014

Tonight...vigorous vorticity maximum noted across the south half of WI...with
low level trough spoke reflection extending from northwest Minnesota across central WI and
toward surface low over lower Michigan. Part of this trough to make it across the
northeastern County Warning Area overnight...but by then heating of the day will be
well over and will walk out any lingering/isolated showers in the
northeastern County Warning Area by 02z. In-wrapping cumulus/stratocu will start to
decrease diurnally after sunset...but may hang on across the
northeastern half long enough through late evening to warrant
partly cloudy to even periods of mostly cloudy wording in these
areas through 11 PM or later. Northwest boundary layer flow to keep
cool air/dry advecting overnight and will keep widespread low
temperatures in the middle to upper 50s going...with some lower 50s possible
near the Highway 20 corridor if cloud cover can clear enough. If it
were not for the mixing northwest surface winds maintaining 7-12 kts
overnight in in-building high pressure gradient...there might be a
shot at record or near record low temperatures at dbq and mli.

Monday...Canadian high pressure to continue to engulf the plains and
upper MS River Valley...with incoming gradient still lingering enough
to make for north winds of 10 to 20 miles per hour through early afternoon
before starting to relax again. Amplifying northwest steering flow
will look to usher down another vorticity complex across northwest into
central Iowa...with several models breaking out light showers across
central into eastern Iowa as the day progresses. While low level lapse
rates will be very steep again...building low to middle level inversion
just above the mixed layer may limit much in the way of precipitation
generation. Plus low level moisture sources dry mixing out. Will keep the
forecast dry for now...with just more cellular cumulus of sctrd to broken
levels forming again by afternoon. Despite robust low level mixing...
incoming cool pool looks to be to an extent that high temperatures will be
limited to the 70s/well below normal...ongoing highs look good and
will make little change. ..12..

Long term...(monday night through next sunday)
issued at 314 PM CDT sun Jul 27 2014

Medium range models continue to be in good agreement with developing
a high amplitude ridge /heat dome/ over the western US with a deep
trough over the eastern Continental U.S.. this upper air pattern will create a
prolonged northwest flow aloft over the Midwest. Pleasant conditions
are expected this week as high pressure builds in from the north
bringing below normal temperatures and low humidity. Highs will be
in the upper 70s to around 80 with overnight lows in the upper 50s
and lower 60s. Late in the week/next weekend the long range models
indicate there is a chance of showers or thunderstorms with warming
surface temperatures and shortwaves rotating through northwest flow
aloft.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1147 PM CDT sun Jul 27 2014

Canadian high pressure building over the northern plains will
provide VFR conditions over the area tonight through Monday.
Winds will be light north to northwest. Although not in the
forecast...there is a low potential that a patch of MVFR clouds
with bases around 2000 to 2500 feet over southern WI could briefly
impact the dbq terminal overnight. Otherwise...there will be a
scattered to broken cloud cover over the region with bases above
5000 feet tonight...then fair weather cumulus clouds at that level
during the daytime hours Monday.

&&

Dvn watches/warnings/advisories...
Iowa...none.
Illinois...none.
MO...none.
&&

$$

Short term...12
long term...Kuhl
aviation...sheets

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