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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
1241 PM CDT Thursday Sep 3 2015

issued at 235 am CDT Thursday Sep 3 2015

Upper ridging and warm and humid air remains in place with little evidence
of any changes. Persistence will be a major contributor to the forecast.
Isolated precipitation in Wisconsin will approach far NE sections of
the forecast area. Area temperatures are similar to last night at 2
am...ranging from 66 to 74 degrees with patchy clouds and light south


Short term...(today and tonight)
issued at 235 am CDT Thursday Sep 3 2015

Short term forecast confidence assessment...good or above average with
once again little sensible weather issues. Persistence and cloud cover
impacts on high temperatures main issue. Like past couple of days this
is at or below low end of guidance. Could be even cooler if more clouds
hang around as in yesterday since were now into early September.

Today...very minor changes. Lowered maximum temperatures most places a
degree of so with highs of 86 to 91 suggested. Winds from the south
at 5 to 10 kts under mostly fair sky and heat indices to rise into
the lower 90s in the afternoon most locations. Isolated shower or
storm may skirt far NE section late PM into the evening hours. If
clouds are in yesterday...highs may still be too high
by at least a couple of degrees.

Tonight...similar to past few nights. Mostly fair with lows upper
60s to around 70 degrees with a light south wind. Should be dry to
mostly dry with risk of isolated evening shower or storm NE sections.

Long term...(friday through wednesday)
issued at 235 am CDT Thursday Sep 3 2015

Main forecast concern in the long term forecast are the chances for
rain from a shift to a more seasonal pattern across the area. The
end of the weekend through the middle part of next week will see
rain and thunder chances across the County Warning Area. My confidence is
increasing that we will see measurable precipitation during this time.

Through most of the weekend the weather will be quiet. Unseasonably
warm temperatures across the area will lead to hot late Summer days
with heat indices reaching into the upper 90s. Sunday afternoon the
remnants of tropical moisture impinge on western areas of the County Warning Area.
With near 12c 700 mb temperatures and convective temperatures that will be large....I
have low confidence that we will see any precipitation across the area.
Did go with a schc probability of precipitation and put it from 21z to 00z Monday. Overnight a
front is forecast to move through the area bringing the best chances
for precipitation across the area.

Sunday night through the rest of the period. The front will move
through the area after 00z on Monday. Cape will be decreasing. While
there will be plentiful low level shear...there will be a dearth of
deep layer shear and MUCAPE. Organized strong storms look unlikely
at this juncture. What may be of larger concern is a threat for
heavy rain associated with any thunderstorms. The cold front is
expected to sag south of the qca and stall out across our area.
This could lead to repeated rounds of convection and heavy rain.
This looks to be of larger concern. At this time will leave out of
the severe weather potential statement as mesoscale features needed for heavy rain are hard to
predict this far out. This needs to be monitored going into the


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1231 PM CDT Thursday Sep 3 2015

A VFR afternoon and evening at most taf sites with light southwesterly
surface winds. A boundary sagging out of WI and northeastern Iowa may
produce an isolated shower or thunderstorm in extreme east central
Iowa and northwestern Illinois...but threat and coverage confidence not
there to put in the dbq taf just yet. Also for dbq...will have to
watch for a broken MVFR deck to push southwest out of WI and possibly
get in the vicinity tonight into Friday morning. Otherwise with light
south winds tonight and mainly clear skies...the chance for MVFR fog
there toward sunrise for most of the taf sites. ..12..


Dvn watches/warnings/advisories...


short term...Nichols
long term...Gibbs

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