Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 281157

Area Forecast Discussion
National Weather Service Quad Cities IA IL
657 AM CDT Fri Oct 28 2016


Issued at 330 AM CDT Fri Oct 28 2016

The latest sfc analysis was indicating high pressure slipping off to
the east acrs the southern GRT LKS and OH RVR Valley, while a low
pressure system was organizing over the far northwestern high plains.
Sfc pressure falls were really increasing acrs the eastern
Dakotas, while the pressure gradient between the two main systems
was tightening acrs the central plains up into the upper MS RVR
Valley. Aloft, 00z upper air analysis and mid/high level moisture
flow fields seen on water vapor imagery, were indicting broad
upper ridging occupied much of the western into central CONUS.


.SHORT TERM...(Today and Tonight)
ISSUED AT 330 AM CDT Fri Oct 28 2016

Today...A windy and unseasonably warm late October day appears to be
on tap. Just marginal mixing up into base of building inversion/warm
wedge aloft supports widespread highs in the 70s, with most areas in
the mid to upper 70s. A deeper mix would even allow for an 80 degree
reading in some spots. But with extensive cirrus shield flowing
around the periphery of the upper ridge filtering the insolation
today, and various model guidance highs really varying from each
other with mixing depth, am hesitant to go too warm. But may gamble
and lean toward the warmer 00z ECMWF MOS guidance. Fcst soundings
and downward momentum transfer in tightening llvl pressure gradient
support southeast to south winds of 15 to 25 MPH sustained this
afternoon, with gusts 30 to 38+ MPH. Dry down-mixing to battle
higher sfc dpt advection from the south, but values should still
rise into the low to mid 50s as the afternoon progresses. Thus
higher RH values in the lower 60s to mid 50 percent range should
limit a widespread fire danger, but may touch upon some fire
spread potential in unharvested crop fields south of I80 in the

Tonight...125 KT upper jet max streaking along the U.S./Canadian
border will dampen upper ridge axis some, while the main sfc low
skirts out of the northern plains and into the north central GRT LKS
by Sat morning. Trailing sfc front will sag southward toward the
northern CWA by morning, being slowed by coming parallel to mean
steering flow and development of west central plains sfc wave on
it`s western flank. Thus it appears breezy evening winds will
decrease diurnally into the overnight as the front approaches from
the north/northwest. Still with expected cirrus and possible mid
clouds, as well as being in the warm sector expect overnight lows to
range in the upper 50s to lower 60s. These overnight lows closer to
normal highs for this time of year. The NAM breaks out dense fog in
the convergent VCNTY of the front along the HWY 20 corridor later
tonight and into early Sat morning, but feel that model may be
overdoing it in a warming dry precursor day and will not mention the
potential acrs these areas yet in any products. Will let the day
shift assess the fog chances near the front.    ..12..

.LONG TERM...(Saturday through next Thursday)
ISSUED AT 330 AM CDT Fri Oct 28 2016

Mostly dry to dry and generally above normal temperatures.

Long term forecast confidence assessment...good or above average with
limited sensible weather issues. Main topic this cycle is limited risk
of isolated, non-severe storms late Saturday and again middle of next
week. Precipitation amounts both events should be light to locally moderate.
Otherwise, most highs and lows should be within 3 degrees. Prefer a
default mix of 50/50 blend of GFS with Hi-res ECMWF.

Saturday and Saturday Night...A weak cool front will drag across the
region. Highs ahead of the front will rise well into the 70s with upper
60s suggested north of highway 30. Chance of showers with light amounts
Saturday night behind front. Local tools suggest not enough instability
and forcing to support having isolated storms. Any rain amounts are
likely in light category and generally spotty over norther 1/2 of area.
Mins behind front to fall into mid 40s north to mid 50s south.

Sunday and Sunday Night...Fair and cooler with only slightly above normal
temperatures. Highs 55 to 65 and lows 45 to 55.

Monday and Monday Night...decent moderate southerly winds ahead of next
system should allow for highs upper 60s to upper 70s and mins in the

Tuesday through Wednesday...frontal system to bring clouds with showers
and isolated storms Tuesday night through Wednesday night. Highs generally
60s to near 70 south and mins 45 to 55 degrees. Rainfall totals mainly
suggested to quarter inch or less with isolated to scattered .25 to
.75 inch amounts with PW`s less than 1.25 inches with no major wave
or forcing suggested.

Thursday and Friday...once again slightly above normal with highs mostly
upper 50s to mid 60s and lows mostly in 40s with some upper 30s possible.


.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
ISSUED AT 646 AM CDT Fri Oct 28 2016

Areas of MVFR fog, along with patches of LIFR CIGs especially in
VCNTY of DBQ, will lift after 9 AM CDT this morning. Then VFR CIGS
and VSBYs through evening with brisk south to southeasterly sfc
winds of 15-25 KTS and higher gusts. If southerly sfc winds decrease
to 10-15 KTs along with loosing the gusts by mid evening, 50 KT
winds just 2000 FT AGL from 240 degrees will produce llvl wind
shear conditions for much of the night until around 5-7 AM Sat
morning when the winds are expected to veer west and decrease some
as a front pushes in from the northwest. Some chance that
convergent flow around the front may produce lower CIGs and MVFR
to IFR fog in the VCNTY of DBQ by early Sat morning, but won`t go
quite that pessimistic yet in the TAFs.    ..12..




LONG TERM...Nichols
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