Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46
FXUS63 KDVN 122023

Area Forecast Discussion
National Weather Service Quad Cities IA IL
323 PM CDT Tue Sep 12 2017

Issued at 321 PM CDT Tue Sep 12 2017

Large cloud shield off Irma remnants swirling acrs much of the south
central to southeastern CONUS, with llvl circulation evident
currently acrs the northern AL/MS/TN border region.This feature
continues to enhance subsidence fields/high pressure to it`s north
which includes the local area. Thus generally dry conditions to
continue through the end of the week. But digging upper trof acrs
the Pacific NW and Intermountain region later this week to disrupt
the blocked pattern, with increasing warmth into the weekend along
with rising chances for precip with moisture return by late Saturday
into Sunday.


.SHORT TERM...(This Evening through Wednesday)
ISSUED AT 321 PM CDT Tue Sep 12 2017

Tonight...With ongoing dry subsidence fields, just expect varying
amounts of the cloud shield rotating acrs the area tonight,
especially the southeastern third to half of the DVN CWA. There may
be a mid deck pushing into the southeast late tonight after
Midnight, but feel even sprinkles will have trouble making it into
the far east and southeastern CWA through sunrise and go with a dry
fcst. With the clouds and enough of a gradient to keep at least 4-6
MPH wind going in the southeast, these areas may have trouble
dipping out of the mid 50s. Otherwise will play the cooler of
guidance lows and even undercut those in some locations where drier
sfc dpts linger. All in all, a lot of 50-55 degree readings by early
Wed morning and a shot at an upper 40. Where there is a higher sfc
dpt field in the upper 50s in the northwest, where winds will go
lighter near a sfc ridge lobe and less cirrus expected, at least
some patchy fog may form before dawn.

Wednesday...Expect more high and some mid clouds filtering the
insolation in the east and southeast on Wed, possibly limiting temps
in those areas to the mid and upper 70s like what is currently
taking pace acrs central into southern IL ATTM. Otherwise, thinner
cloud cover and ongoing dry airmass to allow for more lower 80s acrs
the area, with some areas pushing the mid 80s. Again, will side with
the dry solutions and keep light showers and sprinkles at bay just
to the east/southeast of the local fcst area Wed morning into early
afternoon and will go with unmentionable 10-14 POPs in these
areas.   ..12..

.LONG TERM...(Wednesday Night through next Tuesday)
ISSUED AT 321 PM CDT Tue Sep 12 2017

Southerly flow ahead of a weak cold front will result in a warming
trend through the end of the week into the weekend. Nudged
Saturday`s max temps slightly above the SuperBlend into the mid to
upper 80s, but still not as high as the raw GFS/ECMWF which have
lower 90s for most of the CWA. Model 850mb temps near 20 C are
supportive of highs around 90 F - as long as cloud cover is minimal.

Scattered showers and thunderstorms are possible mainly Saturday
night into Sunday morning along and ahead of a cold front.
But significant 500mb height falls are forecast to stay well north
of E Iowa/NW Illinois, so forcing for ascent and the threat for
widespread appreciable rainfall is low. As a result, the abnormally
dry to drought conditions (depending on location in the CWA) will

For Tuesday and beyond, the GFS is a wet outlier with an active warm
front setting up, while the CMC and ECMWF are dry with an upper
ridge expanding over the central U.S. If the latter models are
correct, very warm temperatures would return for the middle to end
of next week. Uttech


.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
ISSUED AT 1241 PM CDT Tue Sep 12 2017

High pressure/subsidence fields north of Irma remnants will
maintain another VFR TAF cycle through Wed morning. Just varying
amounts of passing high clouds off Irma circulation, and east to
northeast winds of 5-10 KTs going light overnight. Will not put
any VSBY reduction in the TAFS for now, but a low chance of some
fog late tonight where winds go calm and cirrus very thin mainly
toward/in the VCNTY of CID and DBQ.    ..12..




LONG TERM...Uttech
AVIATION...12 is the U.S. government's official web portal to all federal, state and local government web resources and services.