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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
246 PM CDT sun Apr 26 2015

Synopsis...
issued at 245 PM CDT sun Apr 26 2015

Other than a few cumulus clouds mainly across northern
Illinois...the sky was sunny through early afternoon. Middle
afternoon temperatures were generally in the 55 to 60 degree
range...with a northeast breeze.

&&

Short term...(this evening through monday)
issued at 132 PM CDT sun Apr 26 2015

The main forecast issues in the short term period are temperatures
and frost potential for tonight.

Surface high pressure will remain in place across the forecast
area through the period. Have followed previous shift idea of
favoring the lower end of temperature guidance...especially with winds
likely lighter than previous night. This yields low 30s
north...middle 30s central...upper 30s south. Temperatures across the north
will likely be near or slightly warmer than Sunday morning...when
there were only reports of patchy frost. So...will expand the
mention of patchy frost a bit farther south in the forecast
zones/grids...but lacking the expectation of widespread frost...will
not go with a headline at this time.

For Monday...modest airmass modification should produce highs
roughly 3 to 5 degrees higher than today...generally in the 60 to
65 degree range.

Long term...(monday night through sunday)
issued at 132 PM CDT sun Apr 26 2015

High pressure will remain over the Great Lakes Monday night through
Wednesday resulting in quiet weather with cool nights and warm days.

Light winds late Monday night into early Tuesday morning may allow
for some patchy frost to again develop in sheltered low areas and
river valleys across the north half of the area.

A gradual increase in clouds late Tuesday night and early Wednesday
should prevent any additional frost from developing. However...one
cannot entirely rule out some very localized frost.

Wednesday night on...

The model consensus continues the quiet and dry conditions across
the area Wednesday night through Thursday night with stalled high
pressure over the Great Lakes. Temperatures should average a little
above normal.

A weak upper level disturbance begins moving out of the plains on
Friday. The model consensus has dry conditions on Friday due to
limited moisture.

Friday night the model consensus has slight chance probability of precipitation as the
previously mentioned upper level disturbance moves through the area.
Moisture is quite limited and the forcing is weak so the possibility
does exist that Friday night might be dry.

Starting next weekend the models begin diverging on their respective
solutions. The overall big picture does suggest the potential for
the weather pattern becoming more active.

Due to differences in the individual model solutions...the model
consensus has mainly dry conditions for Saturday with slight chance
to chance probability of precipitation Saturday night into Sunday.

&&

Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1214 PM CDT sun Apr 26 2015

Expecting VFR conditions through taf period with high pressure in
place across the region. A northeast breeze will drop off under 5
kts this evening.

&&

Dvn watches/warnings/advisories...
Iowa...none.
Illinois...none.
MO...none.
&&

$$

Synopsis...rp Kinney
short term...rp Kinney
long term...08
aviation...rp Kinney

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