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Area forecast discussion 
National Weather Service Springfield MO
1159 am CST Sat Dec 20 2014

Short term...(today and tonight)
issued at 340 am CST Sat Dec 20 2014

Low level clouds continue to blanket the region early this morning
with areas of light fog also occurring. There are pockets of fog with
visibilities dropping below a mile at times, but web cams and
observations show that this is not widespread and is only
occurring at times in spots. Still there could be some patchy
areas of fog with visibilities below a mile this morning.

An upper level trough is pushing across the area early this
morning as a secondary wave is also currently pushing southeast out
of Nebraska into northern Missouri. Clouds had been clearing from
west to east across central Kansas overnight behind the lead
shortwave trough. This clearing though has slowed its eastward push
over the last few hours, and clouds are starting to spread north
out of Oklahoma into south central Kansas filling clouds back over
location that were clearing.

Low level moisture remains high across the south and the low level
winds will remain out of the south and expect the moisture to
continue to advect north today, like we are currently seeing
across Kansas. Therefore do not think we will see much clearing
across the area today, with yet another cloudy day expected. The
cloud cover will keep temperatures cooler, however they will
likely be warmer than the last few days. This is because dry air
in the mid levels is advecting into the region behind the
shortwave troughs. Though this dry air advection will be above the
low level moisture, it should make the cloud deck not as thick as it
has been the last couple days when we only saw highs warm a degree or
two from morning lows. As result highs should warm into the lower
40s this afternoon.

The low level moisture should continue to push across the western
portions of the forecast area tonight and have included patchy fog
again for areas generally along and west of Highway 65 tonight
into Sunday morning. This fog should generally be light, a lot
like what is currently occurring across the area. Cloud bases
should start to rise from east to west across eastern Missouri as
drier surface air spreads west and think this will limit fog
potential east of Highway 65 tonight into Sunday morning.

Long term...(sunday through friday)
issued at 340 am CST Sat Dec 20 2014

The cloudy conditions will likely hold on tight across the western
portions of the forecast area on Sunday, but may see some breaks
in the clouds start to occur across the Eastern Ozarks Sunday. Due
to clouds, did knock a few degrees off highs on Sunday, but still
expect temperatures to warm into the middle to upper 40s Sunday
afternoon.

An upper level trough will then push across the plains Sunday into Sunday
night. An upper level low will develop across the northern plains
keeping the main trough axis across the plains through Tuesday. However,
shortwave troughs will move off the main low and across the area
Sunday night into Tuesday before the low and main wave finally
kick through the area Tuesday night into Wednesday. With the shortwaves
tracking through the area could see rain at times from late Sunday
night into Tuesday. It is not expected to rain during this whole
period but will be possible as energy tracks through the area at
times from late Sunday night into Tuesday. Temperatures will
remain warm enough for all rain during this time as the main wave
remains to the west keeping a southwest flow and warm air over the
area.

As the wave kicks through the area later Tuesday into Wednesday
a cooler air mass will spread into the area. There could be some
wrap around light snow on the back side of this low later Tuesday
into Wednesday. This precipitation will be on the light side and
not expecting any accumulations.

An upper level ridge will quickly build over the region on
Thursday resulting in a warm and sunny day as highs top out in the
40s and 50s.

Another upper level wave will then push through the region Thursday
night into Friday. Medium range models differ on the exact timing
of this system. Also, they differ on the amount of moisture return
ahead of the system. With a front pushing south into the Gulf during the
middle of the week, think the 00z European model (ecmwf) may be over doing moisture
return, and have generally gone more with the 00z GFS on the
moisture return. Went with a consensus on the timing and the
track of the system. The track should be far enough north for any
precipitation that can develop to be all rain with the potential
for some light snow possible wrapping around the back side if it
can squeeze it out.

&&

Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1138 am CST Sat Dec 20 2014

A slow improvement in flight conditions will continue this
afternoon, especially at Joplin and Springfield where mainly MVFR
is expected. The Branson terminal will also improve, but will
remain very close to the low end MVFR/high end IFR threshold.
Flight conditions are then expected to deteriorate again tonight
as ceilings lower and fog develops. Dense fog again appears
possible around Branson. As has been the case the last couple of
mornings, ceilings/visibilities will then slowly improve Sunday
morning.

&&

Sgf watches/warnings/advisories...
MO...none.
Kansas...none.
&&

$$

Short term...wise
long term...wise
aviation...schaumann

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