Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 151152

Area Forecast Discussion
National Weather Service Quad Cities IA IL
652 AM CDT Sun Oct 15 2017


Issued at 321 AM CDT Sun Oct 15 2017

The main passing sfc low was noted up near Green Bay ATTM, with eyes
on northern LK MI and deepening to under 1000 MB. Associated
trailing sfc front was pushing acrs the eastern CWA, with lingering
precip conveyor shuttling up along it. Temporary chill down behind
this system for today into Monday under digging mid CONUS upper
trof, then the mean steering flow looks to flatten again for a temp
moderation back above normal as the week progresses.


.SHORT TERM...(Today and Tonight)
ISSUED AT 321 AM CDT Sun Oct 15 2017

Today...tight cyclonic pressure gradient with an embedded
isallobaric rise surge behind the northeastern WI sfc low, will
continue to drive windy conditions acrs the area this morning, with
a few sites in the north not all that far away from advisory
criteria at times until midday and early afternoon gradient
relaxation commences. In general, sustained northwest winds of 20 to
near 30 MPH with gusts well up in the 30s this morning. Robust cool
advection ongoing from the northern plains today to keep highs in
the 50s, thus most sites will have been warmer overnight than they
will be during the day after frontal passage. wrap around cloud
cover will hang on until afternoon scattering out from southwest to
northeast. CU rule parameters suggest any early clearing holes this
morning to "CU" back up for mostly cloudy skies until the clearing
/subsidence takes better hold as the afternoon progresses. The
brisk winds will also relax as the afternoon progresses with
progressive low pressure migration into the northeastern GRT LKS.

Tonight...with sky clear out and upstream sfc ridge lobe adjustment
right acrs the local area for light sfc winds, the challenge becomes
how cold will we get and frost formation potential. Looking at what
upstream sfc temps are doing under clear skies in the central
plains, lends credence to H85 MB cool ridge rule supporting
widespread lows in the mid to upper 30s tonight. These temps and
ambient sfc layer conditions should allow patchy to a few areas of
frost formation acrs much of the northern 2/3`s of the fcst area,
with low lying and river valley regions north of I80 favored. For
now with still marginal sfc temps and coverage expected, will hold
off of an advisory and let the day crew take one more look. But will
continue to touch upon in other products.   ..12..

.LONG TERM...(Monday through next Saturday)
ISSUED AT 321 AM CDT Sun Oct 15 2017

The main theme of the long term period continues to be dry
conditions with a gradual warming trend.

Highs Monday will be in the low 60s, with northwest flow aloft. The
upper pattern will gradually shift from northwest, to zonal, and
eventually southwest late in the period. Highs should be in the low
70s by Friday into Saturday, about ten degrees above normal.

No pops in the forecast until late Saturday. The 15/00z GFS and
ECMWF have similar timing with the arrival of the next significant
wave. The GEM is a fast outlier, and have removed the low pops
generated by the consensus model blend during the day Saturday.

Dry conditions mean no significant impacts to area rivers for the
coming week, with in bank rises forecast on many tributaries and the
mainstem Mississippi.


.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
ISSUED AT 645 AM CDT Sun Oct 15 2017

Ongoing MVFR deck will lift and scatter out from the west as the
day progresses, but most of the TAF sites may not go VFR until
late afternoon. Turbulent wind profiles in the low to mid levels
this morning, with northwesterly sfc winds gusting to at least 30
KTS through midday. High pressure arriving from the west to bring
about clearing skies and decreasing sfc winds for a VFR night
tonight. Valley and ground fog late tonight/early mon morning should
stay away from any TAF site.    ..12..




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