Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 211909

Area Forecast Discussion
National Weather Service Quad Cities IA IL
209 PM CDT Mon May 21 2018

Issued at 150 PM CDT Mon May 21 2018

The weak low continues to slowly drift northeast through our CWA
this afternoon. While the rain amounts have been light since Noon,
when the mid level dry air spread over the region, the low level
convergence in the northern sections continues to generate drizzle
and fog. South of the low track, mild air and very limited heating
has allowed for temperatures to climb to the lower to mid 70s.


.SHORT TERM...(This Evening through Tuesday)
ISSUED AT 150 PM CDT Mon May 21 2018

While the low moves away tonight, the weak flow around it and
saturated low levels will keep conditions damp and mainly cloudy
tonight. Any clearing, which is possible south tonight, will be
accompanied by fog. That fog may be dense and could warrant an
advisory. With the low clouds tonight, temperatures will be slow
to fall, and dewpoints should be maintained. Thus lows in the mid
50s north to the lower 60s south. Any showers after 6 PM will be
isolated and rapidly ending in the far east and northeast.

Tuesday should see a cloudy morning northeast, possibly dense fog
in the south, with improving conditions everywhere during the day,
as high pressure moves through the region. This surface high will
move quickly east, but the upper level ridge is expected to remain
west of our CWA. That sets the stage for warm advection
thunderstorms well northwest of the CWA Tuesday night, which
could, in a dissipating mode, slide towards the CWA after
midnight. While pops are in the chance range late at night
northwest, it seems any significant thunder will remain well west
of our area.

.LONG TERM...(Tuesday Night through Monday)
ISSUED AT 150 PM CDT Mon May 21 2018

Warm and rather humid weather will last through the extended, with
some threat for thunderstorms at times, with the southern edge of
the zonal flow aloft nearby, and at times a weakness in the upper
ridge indicated by models. This mid summer pattern does not
support high pops and anyone with outdoor plans this Memorial Day
weekend should view this as typical summer weather, not a wash

Highs in the lower to mid 80s each day will drop to the lower to
upper 60s at night. This pattern would support hot and humid
weather if the moisture transport were stronger, but with the gulf
appearing blocked by the flow around the tropical disturbance
there, we`ll just be dealing with Midwestern transpiration from
soil and plants.



.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
ISSUED AT 1219 PM CDT Mon May 21 2018

Low pressure will very slowly move northeast over the area this
afternoon, moving through the lower Great Lakes tonight. Winds
will gradually shift from east to south to west to northwest as
the low passes by, but they will remain light to under 10 kts in
all times. Through late afternoon, CIGS will vary from 200 ft to 8
ft AGL, with occasional fog/drizzle/light rain lowering visibility
to 1 to 4 miles. This LIFR condition will slowly improve,
especially on visibility towards evening, before some possible fog
again overnight.

Tuesday, improvement to VFR should eventually occur in all areas
as the system moves farther away.




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