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fxus63 kdvn 171134 

Area forecast discussion
National Weather Service Quad Cities Iowa Illinois
634 am CDT Tue Oct 17 2017

..aviation update...

issued at 324 am CDT Tue Oct 17 2017

An area of high level clouds overspread eastern Iowa and northern
Illinois during the overnight hours. A southerly breeze averaged 5
to 10 mph. Early morning temperatures ranged from the upper 40s to
mid 50s.


Short term...(today and tonight)
issued at 324 am CDT Tue Oct 17 2017

The main forecast issue in the short term period is temperatures.
Warm air advection will continue to pick up today with a southwest
breeze gusting around 20 mph and plenty of sunshine. Have bumped
afternoon highs up slightly, especially west where the warmest
850mb temps will reside. Afternoon highs should reach the upper
60s to low 70s, about 10 degrees above normal for the date.

For tonight, expect a mostly clear sky and a south wind staying up
around 5 to 8 mph. Lows will be in the mid to upper 40s.

Long term...(wednesday through monday)
issued at 324 am CDT Tue Oct 17 2017

Wednesday through Friday...rather breezy mild day Wed ahead of
incoming sfc front squeezed in between ridge centers. Mixing up to
base of 800 mb mb inversion combined with plenty of insolation make for
widespread highs Wed in the low to mid 70s. Then a dry frontal passage lays
through the area Wed night into Thu morning, with weaker sfc wind
flow and mixing expected in the vicinity of this feature for Thu.
With not much in the way of airmass change, highs on Thu may be
similar to Wed or a degree or two cooler due to less mixing depth.
Passing sfc ridge and upstream llvl trof/front organization acrs the
Western Plains re-invigorates warming southerly return flow by
Friday. Currently projected llvl thermal profiles supports
unseasonably mild highs in the mid to upper 70s for Fri, with an
outside chance at an 80 degree reading somewhere as long as the day
remains sunny.

Saturday through Monday...latest suite of medium range model runs
still advertise increasing southerly warm moist conveyor up off the
western Gulf and to the leeside of an approaching l/west upper trof
with an associated north-to-south oriented sfc front. This should
bring about the next passing precip event to the area sometime this
weekend, but still within model variances at this point. The general
trend with the 00z runs is a bit more progression with the sfc
front. Both the 00z GFS and European model (ecmwf) now break out wings of warm
frontal showers and even some thunder earlier in the day Sat acrs
the cwa, before the main event of frontally scooped up long fetch
conveyor of showers and embedded thunder sweep through later Sat
night into Sunday morning. The slower European model (ecmwf) lingers rains well into
Sunday and is less wet, while the more progressive GFS sweeps the
rain east by mid Sunday morning. The GFS is also more bullish with
it's moisture draw this far north and produces well over an inch of
rain in the south half of the County Warning Area. The European model (ecmwf) is more in the way of
0.25 to 0.75 of an inch for the local area with its higher amounts
acrs the western County Warning Area. For now will still target Sat night into early
Sunday as the main precip window with high pops, but wonder with
amplified upper trof and flanking ridges, if further model runs will
trend slower again.

Post-system cool down then looks on tap for early next week, with
some chance for sctrd instability showers later Monday and in/under
base of deepening cool core upper trof overhead. ..12..


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 633 am CDT Tue Oct 17 2017

Low level wind shear will continue until 14-15z this morning
before surface winds increase from the soutwest. Kcid/kdbq will
gust at or above 20 kts this afternoon. Otherwise, expect some
passing high clouds this morning with VFR conditions through the


Dvn watches/warnings/advisories...


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