Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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FXUS63 KEAX 270532

1232 AM CDT Sun Jul 27 2014

Issued at 1022 PM CDT SAT JUL 26 2014

Quick update this evening to account for latest trends. Have removed
pops through the overnight period as no precip is occurring across
the CWA. In fact...latest arriving 00z NAM maintains a dry fcst despite
the expected passage of a cold front overnight. Main issue continues
to be warm air aloft which is providing modest capping aloft as seen
on latest AMDAR soundings from MCI. Moreover...large scale forcing
for ascent remains very weak as region remains in an areas of NVA
following this afternoon/s MCV passage. In general...could no longer
justify slgt chc-chc pops any longer given the current trends and
fcst has been adjusted accordingly.


.SHORT TERM...(This Evening through Monday Night)
Issued at 323 PM CDT SAT JUL 26 2014

The main concern for the near term is if we see any additional
convection, where it may be and whether we see any severe

The MCV moving over the eastern portions of the forecast area has
blossomed new showers and storms east of the forecast area. While
there is modest instability for this area to work with, shear
remains very weak. Subsidence on the immediate tail end of the MCV
should inhibit additional convection temporarily. Focus then shifts
to storms in eastern Nebraska, whether they will survive further
south and if additional convection can develop in between the back
edge of the MCV and the Nebraska convection. There are a few fairly
large negatives. The first and what may inhibit storms all
together, is very warm air aloft. The 18Z TOP, OAX and SGF soundings
all showed, to some degree, a strong cap from very warm air aloft.
The second is relatively weak shear further south. This factor
though will become less of an issue as stronger winds aloft build
south and eastward ward and enhance shear further to the south and
east this evening.

Short-term higher resolution models favor very limited or even dry
conditions this evening and tonight. And even the coarser synoptic
scale models don`t indicate much precipitation moving into or
developing within the forecast area. It seems more likely that the
warm air aloft will inhibit convection despite there being robust
instability and increasing shear across northern Missouri. At this
time the risk of severe weather is very conditional on whether
enough forcing and/or cooling of air aloft can overcome the cap. So
for now, have maintained chance PoPs across mainly the northeastern
third of the forecast area for the evening hours.

The cold front will move through the area tonight and usher in
cooler and drier air to the region. There may be some showers/storms
develop along the front but as previously mentioned, shear decreases
further south and there will remain a nose of warm air aloft likely
inhibiting development. The cooler and drier air moving in will
result in highs in the 80s for both Sunday and Monday with dewpoints
in the 50s.

Regarding the heat advisory, temperatures will have the potential to
rebound quickly and limited mixing has kept dewpoints in the low to
mid 70s. It seems the greatest potential for areas to see at least a
few hours of excessive heat will Miami and Cass southward. For now
will keep the advisory going until we`re past peak heating and the
potential for a quick spike into the mid 90s has passed.

.LONG TERM...(Tuesday through Saturday)
Issued at 323 PM CDT SAT JUL 26 2014

Tuesday through Saturday: Models continue to advertise a highly
amplified upper trough to reside over the eastern CONUS through much
of next week. This will result in unseasonably cool weather to
persist during the extended period. Maximum readings each afternoon
are expected to only warm into the lower 80s, with low temperatures
in the lower 60s. A dry atmosphere is expected to remain in place
with relative humidity below 20 percent through the H7-H4 layer.
Continued a slight chance of precipitation Thursday and Friday, but
overall probabilities remain low for any measurable rainfall during
the period.


.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1227 AM CDT SUN JUL 27 2014

First of two frontal boundaries to sag south across the region
overnight. The first will result in a wind shift to the
northwest...while the second will result in the influx of much drier
air after 12z. In between these to boundaries...moist low-level
conditions will support developing MVFR VSBYs at STJ after 10z.
Conditions should quickly improve after 12z with northwest winds
increasing to 10-15 kts during the daylight hours.




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