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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
620 am CST Monday Nov 30 2015

..updated aviation discussion...

issued at 300 am CST Monday Nov 30 2015

Bright banding on dvn radar and latest observation from Dubuque
Airport both suggest that some sleet is mixing in with the rain.
Temperatures have fallen to 32 f across Buchanan/Delaware/and
Dubuque counties but Road surface temperatures are a degree or two
warmer thereby precluding much of a threat for icing. Nonetheless
there remains a possibility for light icing on elevated surfaces
and untreated roads/sidewalks. Not expecting anything widespread
but there could be some isolated slick spots as highlighted in the
Special Weather Statement that is in effect for the tier of
counties along Highway 20 through approximately 530 am CST.


Short term...(today and tonight)
issued at 300 am CST Monday Nov 30 2015

Today...surface low track across western Iowa will cause surface winds to
veer to the southeast with time. Temperatures are forecast to slowly
warm to the upper 30s near 40 f by the afternoon. All precipitation
that falls today will fall as plain rain as temperatures remain above

Overall the morning hours look fairly quiet with only isolated to
scattered rain showers and not much in the way of quantitative precipitation forecast. But another
wave of forcing is forecast to move in from the west during the
afternoon/evening providing the bulk of the rain with this event. Layered
q-vector convergence...850mb WV transport...and 925mb-850mb warm air advection
will all increase in the southeast sector of the surface/mid-level low
during this time.

Additional rainfall...from this morning through tonight rainfall
is forecast to range from near 0.25 inches over the southern dvn
County Warning Area to near 0.50 inches across the northwest.

Tonight...cold front forecast to push through east Iowa/west Illinois
between 2-4 am CST. Cold air advection will develop...via gusty southwest winds
of 20-25 miles per hour...changing any residual light showers to flurries or
isolated light snow showers. No snow accumulation is anticipated.
Lows will be in the lower 30s west and middle 30s far
east. Uttech

Long term...(tuesday through sunday)
issued at 300 am CST Monday Nov 30 2015

Expect lingering light snow/flurries Tuesday and Tuesday
night...mainly along and north of the Interstate 80 an
upper level low pushes through the region. Some light snow may
linger into Wednesday morning in the far east. Only minor
accumulations...if any...are expected through the period...although
it does not take much to create a few slick spots. Tuesday will be a
rather raw day with a west/SW wind gusting around 25 miles per hour and temperatures in
the low 30s to low 40s. For Wednesday through Sunday...expect dry
conditions with gradual warming to above normal temperatures. By the
weekend...expect highs in the 40s area-wide with lows in the upper
20s/low 30s.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 607 am CST Monday Nov 30 2015

Conditions will deteriorate through this taf period. As surface low
approaches western Iowa...steady east/southeast winds will develop over east
Iowa/west Illinois. Moisture will increase and periods of -ra will
become widespread during the aftn/evening. Ceilings will drop to
IFR from the middle/late afternoon through at least 06z/Tuesday and could
occasionally fall to LIFR. Visibilities should stay mostly at IFR. Winds
will veer to the SW after 08-09z/Tuesday behind a cold front. Uttech


Dvn watches/warnings/advisories...


short term...uttech
long term...rp Kinney

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