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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
607 PM CST Tuesday Dec 1 2015

issued at 315 PM CST Tuesday Dec 1 2015

12z upper air analysis has an 850mb low in southwest Minnesota with an 850
mb cold front from Upper Michigan...through Indiana...and into
northeast Texas. A trough ran from the low into southwest Kansas.
Satellite and radar trends show wrap around clouds from the storm
system moving east across Iowa with snow showers developing. Little
if any clouds ran from northeast Illinois into the Southern Plains.

18z surface data has a low in southwest Minnesota near krwf. The main
front ran east from the low across Wisconsin and then south into
Ohio and then Mississippi. Dew points were in the 30s and higher
east of the Mississippi and into the Ohio Valley. Dew points were in
the 20s across the central and northern plains.


Short term...(late this afternoon through wednesday)
issued at 315 PM CST Tuesday Dec 1 2015

Radar trends show isolated to scattered snow showers have broken out
west of a Freeport to Ottumwa line. Based on rap trends...these snow
showers will continue through the late afternoon and into the early
evening hours generally west of a krfd to Kirk line. A dusting is
possible on the grass and elevated surfaces. Pavement temperatures
are above freezing so the snow should melt on the roads.

There may be a lull in activity late this evening before new snow
showers develop across the area as the upper low moves into
Wisconsin. The better chances generally look to be along/north of I-
80 and any accumulation should be a dusting.

On Wednesday...the nocturnal snow showers will move out of the area
during the morning. There may or may not be a lull in activity in
the late morning. Accumulations Wednesday morning should again be a
dusting at best.

New diurnal snow showers will develop Wednesday afternoon with the
better chances east of the Mississippi. The best chances for snow
showers actually look to be east of I-39. The question Wednesday
afternoon is will there be any new accumulation. At best there may
be a dusting on the grass or elevated surfaces.

Long term...(wednesday night through tuesday)
issued at 315 PM CST Tuesday Dec 1 2015

Main forecast concern for the long term are the above normal
temperatures forecast through the period and a chance for
precipitation at the end of the period. At this time it looks like
there is a low chance for precipitation and a good chance for temperatures
to reach near 50 this weekend.

Large scale ridging will turn to SW flow late during the week.
Moderation under this ridge along with the SW flow will lead to well
above normal temperatures. Highs on Saturday could be as high as 10
degrees above normal across most of the area. Little to no sensible
weather is expected during this time with the exception of some
clouds associated with a middle level wave middle week.

Middle weekend an advancing middle level wave and trailing cold front are
forecast to sweep through the area. Models are in good agreement
with the large scale pattern and flow. However...the mesoscale
features associated with the cold front are leading to limited
forecastability for any precipitation along the front. At this time...the
best chances for precipitation look to be across southern zones. This will
likely change as we approach the weekend. Regardless...most of the
long term forecast looks to bring warmer temperatures and quiet
weather to the area.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 602 PM CST Tuesday Dec 1 2015

Mostly VFR conditions the next 24 hours. The region to remain under
cyclonic flow resulting in lots of clouds with scattered flurries and
snow showers. The heaviest snow showers may lower visibilities to 2
miles or less for short periods of time with bases down to 1-2k above ground level.
Otherwise...visibilities to be 6 plus miles with ceiling at or above 3k above ground level.


Dvn watches/warnings/advisories...



short term...08
long term...Gibbs

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