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

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FXUS63 KEAX 042330

630 PM CDT Sat Jul 4 2015

Issued at 325 PM CDT SAT JUL 4 2015

The holiday continues to be as benign as forecast with some clouds
in the upper levels streaming through and temps running below
normal for early July. Surface high pressure responsible for this
pleasant weather has already begun shifting off toward the east,
allowing for southerly return flow on its backside, already noted
across eastern KS and extreme western MO. Despite this return flow
setting the stage for WAA as well as atmospheric moisture to be on
the increase tomorrow, looks like wedge of mid- to upper-level
drier air will inhibit widespread precip chances until the
approach of the well-advertised frontal boundary on Monday.
Any pop-up convection tomorrow will generally be possible across
the western third of the forecast area, with increasing chances
overnight across NW MO as the LLJ ramps up.

Models are still trying to come into better agreement with the
details of the fropa on Monday with differing timing between the
GFS, ECMWF, and NAM. The 12Z NAM was the fastest (with the 18Z NAM
coming in a little slower) and the 12Z ECMWF coming into better
agreement with the timing of the 12Z GFS. With the front still
just outside of the range of the higher-res models, the next
update or two will be able to incorporate those models into the
forecast as well. What has been very consistent from run-to-run,
day-to-day is that the potential for at least moderate to possibly
heavy rainfall continues to be the primary concern with this
system. PWATs look to be above average even for this time of year,
and the potentially slow moving nature of the front will
contribute to the heavy rainfall threat. With zonal flow aloft and
an ill-defined upper-level synoptic pattern to help the front
remain progressive, model output QPF is hinting at over 2 inches
of rain falling on already saturated grounds. From a severe
weather potential, with the aforementioned limitations in mind, it
looks to be on the lower side with fairly insignificant deep layer
shear, although plentiful SB instability ahead of the front will
be readily available before model soundings show a transition to a
deep layer moisture profile reminiscent of the discussed moderate
to heavy rainfall threat.

Decent precip chances remain in the forecast through late Tuesday
as the front slows and struggles beyond southern MO. It is from
around the middle of the week onward that model divergence on
solutions in a zonal and weaker flow pattern yields lowering
confidence in the latter portions of the forecast period.
Perturbations trekking through keep the extended forecast period
unsettled as the region sits under a more typical summertime pattern.

Temperatures returning to normal for this time of year arrives
tomorrow with highs in the upper 80s, continuing through Monday
across the southern two-thirds of the forecast area on Monday
ahead of the front and precip. Cooler temps arrive on Tuesday
behind the front and most likely under cloud cover with temps
slowly on the rebound through the rest of the week. Lows will
respond accordingly with the warmest overnight temps looking to be
tomorrow night under southerly flow.


.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 630 PM CDT SAT JUL 4 2015

VFR conditions expected through the fcst period. Light southeast
winds of 4-8 kts overnight will increase to 10-15 kts after 13z as
daytime mixing commences. Upper CI this evening will give way to
scattered fair weather CU centered around 4 kft by late morning.
Cannot rule out an isolated shower or storm by mid/late afternoon but
anticipated areal coverage precludes mention for now.




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