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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
334 PM CDT Friday Jul 3 2015

Synopsis...
issued at 136 PM CDT Friday Jul 3 2015

Scattered fair weather cumulus clouds were common during the early
afternoon...especially along and east of the Mississippi
River...along with abundant haze/smoke. Afternoon temperatures
were in the low to middle 70s.

&&

Short term...(this evening through saturday)
issued at 136 PM CDT Friday Jul 3 2015

Quiet conditions will continue through the entire short term
forecast period with little in the way of sensible weather.

For tonight...expect a clearing sky and light wind...allowing
overnight temperatures to drop into the middle to upper 50s. There
may be some light fog...but visibilities will not be low enough to
be an impact...with the exception of the aviation community. For
the 4th of July Holiday...expect more haze with some afternoon
cumulus developing. The haze should keep afternoon temperatures down
slightly...despite the moderating airmass. Based on this
afternoons temperatures...a 2 to 4 degree bump yields highs generally in
the 81 to 83 degree range.

Long term...(saturday night through friday)
issued at 136 PM CDT Friday Jul 3 2015

Overview...a cold front will bring a good chance for showers and
thunderstorms on Monday into Monday night across eastern
Iowa...western Illinois...and northeast Missouri. Expect warm and
humid conditions preceding the front on Sunday...with slightly
cooler but still humid weather on Monday. High pressure will then
move across the Midwest and Great Lakes Tuesday through Thursday
resulting in pleasant temperatures and mostly dry weather.

Sunday...seasonal with very warm and humid conditions. Forecast
highs are several degrees above consensus because daytime mixing in
S/SW low-level flow combined with nearly full solar insolation
should bump maximum temperatures into the middle to possibly upper 80s. Forecast
soundings are showing bl mixing up to 850mb where temperatures are near 16-
18 c...1000-500mb thickness values should reach to 576 dam.

Monday and Monday night...a middle-level trough is forecast to push
into North Dakota/Minnesota/Wisconsin through the day which will
keep associated synoptic dynamics north of the dvn County Warning Area. At this
time...it appears the best chance for showers and storms over east
Iowa/west Illinois/NE Missouri is during the late afternoon and through the
evening. However...there may be remnant showers/storms that move
through during the late morning into the early afternoon from convection
that developed in the plains on Sunday. Increasing clouds will hold
temperatures down compared to Sunday. There should be a west to east
gradient ranging from the upper 70s across the western forecast area
to the middle 80s over the far east.

High surface dewpoints in the upper 60s to lower 70s on average will support
moderately high MUCAPE values between 2500-3500 j/kg. However...with
the main shortwave so far to the north...0-6 km bulk shear will be
mostly under 30 kts...precluding widespread severe potential. Simply
based on the thermodynamics isolated strong to severe storms are
possible. Additionally...precipitable waters potentially near 2 inches...or 1.5-
2.0 Standard deviations above normal for early July...means
torrential rainfall rates are possible with the strongest storms.

Tuesday and Wednesday...very nice stretch of weather as surface high is
in control. Expect highs in the upper 70s and lows near 60 f...mostly
dry conditions...and comfortable humidity.

Thursday and Friday...pattern will slowly begin to change with
southwesterly surface-850mb winds increasing downstream of a middle-level
trough developing over the northern rockies. Surface dewpoints and
humidity will be increasing during this time but overall threat for
rain looks to remain low until the aforementioned trough approaches
the forecast area possibly Friday night into Saturday.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1230 PM CDT Friday Jul 3 2015

Expect light and variable winds becoming light westerly overnight.
Other than few/scattered diurnal cumulus this afternoon...the sky will
be clear. There is some potential for some MVFR fog during the
early morning at all taf sites...but dense fog development not
expected.

&&

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

$$

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

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