Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 222033

Area Forecast Discussion
National Weather Service Quad Cities IA IL
333 PM CDT Sat Oct 22 2016

Issued at 330 PM CDT Sat Oct 22 2016

At 2 PM CDT...generally clear skies with temperatures in the 60s
and south to southwest winds of 5 to 15+ MPH noted across the forecast
area. Upstream analysis shows next front with little moisture to
arrive late Sunday. Dry conditions should continue for at least
the next 3 days.


.SHORT TERM...(This Evening through Sunday)
ISSUED AT 330 PM CDT Sat Oct 22 2016

Short term forecast confidence assessment...good or above average with
little sensible weather issues. Forecast highs and lows most to all
locations should be within 3 degrees tonight with highs tomorrow possibly
a few degrees still too low for later shifts to reassess.

Tonight...clear and south winds of 3 to 6 MPH should allow for temperatures
to fall back well into the 40s with lower 40s northeast to the upper
40s far south.

Sunday...westerly winds of 10 to 20+ MPH expected before front passes
mid to late day. Decent BL mixing suggested most locations may be a
couple degrees too low and in some places 3+ degrees warmer. Otherwise,
a splendid late October day, mainly 67 far northwest to 74 degrees.

.LONG TERM...(Sunday Night through next Saturday)
ISSUED AT 330 PM CDT Sat Oct 22 2016

Sunday night and Monday...Post-frontal high pressure building down
acrs the upper MS RVR Valley Sunday night. Associated drier sfc dpt
advection and northerly LLVL flow decreasing late under mainly clear
skies to make for lows in the mid to upper 30s north of I80, to the
lower 40s in the south. Broad scale omega upper ridge as well as
western GRT LKS sfc anticyclone to make fro a fair wx Monday with
near normal temps. Light southeasterly return flow increasing Mon
night into Tue morning ahead of west central plains llvl cyclogenesis
region, to make for lows not quite as cool as what occurs Sun night-
Mon morning.

Tuesday and Wednesday...The main weather story will be the rather
vigorous wave undercutting the ridge and propagating eastward acrs
IA from late Tue night through Wed evening. Digging extent of
the upper jet max, as well as wave energy deflection by lingering
ridging suggest a further south path of the main low as compared to
older model runs, and the 12z GFS and ECMWF seemed to have picked
up on this and have adjusted further south some. Thus the latest
thinking would suggest elevated WAA type rain band increasing north
of I80 from west to east later Tue afternoon and especially at night
as saturation processes of the lower layers matures. With the
further south trend, the precip may be mainly stratiform rain Tue
into Tue night. Will keep isolated embedded thunder as Tue night
progresses and into early Wed morning, as plume of mid layer MUCAPES
of 300-500 try to arrive from the west and southwest. Longer range
PWAT feed projection also will look to spike well above normal into
the 1.2 to 1.4 inch range by Wed. Thus half inch to over an inch
possible along and north of the HWY 30 corridor by Wed morning with
the highest amounts acrs the western HWY 20/HWY 30 corridors.

Showers with embedded thunder to progress eastward acrs the area Wed
into Wed evening, with the main sfc low probably moving along along
or just north of I80. Southern edge of main Def Zone-like precip
band will look to continue to clip the HWY 30 and points north areas
into early Wed evening before starting to diminish. If the currently
projected PWAT feed is close, these northern areas may get up to
another inch of rain on wed on top of what they got Tue night. Rain
and clouds will look to hold temps down in the 50s even along and
south of the main warm front acrs much of the area, with maybe just
the far south touching 60. The far north may be held to around 50 or
the low 50s. A further south main low track adjustment in later model
runs will make all these parameters have to shift to the south as
well. A breezy post-wave day on Thu with eventual clearing by mid
afternoon from west-to-east...highs in the 50s to low 60s.

Thursday through next Saturday...longer range projections suggest
eastern GRT LKS L/W troffiness and re-amplifying mid conus upper
ridge to make for little in the way of organized precip makers at
the end of the week, maybe until a ridge-riding short wave can
gather enough moisture feed to possibly produce some showers in or
near the local area later on Sat. Current suite of medium range
models are really varying on strength and timing of this potentail
weekend cyclone acrs the upper midwest. But ensemble mean path and
timing suggests pre-system warm draw to make for above normal temps
again by next Saturday.   ..12..


.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
ISSUED AT 1216 PM CDT Sat Oct 22 2016

Weak high pressure will result VFR conditions with clear to mostly
clear skies and light southwest to south winds the next 24 hours.





SHORT TERM...Nichols
AVIATION...Nichols is the U.S. government's official web portal to all federal, state and local government web resources and services.