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Area forecast discussion
National Weather Service Kansas City/Pleasant Hill MO
1114 PM CDT Tue Apr 15 2014
issued at 406 PM CDT Tuesday Apr 15 2014
No major systems to contend with over the next 7 days but there will
be a couple of weak features which will bring a threat of relatively
light precipitation...one on Thursday and the other Saturday
High pressure from the Great Lakes into East Texas will shift quickly
east with increasingly strong southerly flow spreading west to east
tonight. A very strong low level jet with h8 winds from 50-60kt is
expected to develop from the Texas Panhandle through west Iowa later
tonight. This swath of winds will overspread the County Warning Area on Wednesday
with strong mixing generating sustained surface winds from 20-25kt
with gusts approaching 40kts or just below Wind Advisory criteria.
These winds will also draw in an elevated warm and dry mixed layer.
See fire weather section for details on fire weather danger.
A clipper type upper system will zip through NE/IA/MN Wednesday
night and force a cold front into the County Warning Area. While the clipper passes
to the north the cold front will likely stall somewhere over the
County Warning Area. Models are similar in handling a second more southern shortwave
tracking east out of Colorado on Thursday. Layered frontogenesis will
likely provide sufficient moist ascent to wring out some light rain.
While the GFS, which just 3 days ago had forecast a snowstorm here,
is tracking the bulk of the rain further south, even the European model (ecmwf) and
NAM have been trending further south as well. So, have trimmed back
pops and shifted area further south.
Friday and saturday:
Benign weather pattern as a shortwave ridge shifts northeast with
increasing warm air advection. After a cool start on Friday we
should see seasonal or slightly warmer temperatures on Saturday.
A southern stream system with increasing isentropic ascent will
likely generate scattered convection starting as early as Saturday
night. System looks weak enough with minimal instability to preclude
a severe threat.
Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1110 PM CDT Tuesday Apr 15 2014
Cirrus continues to spill across the terminals at midnight. However
the big aviation story will deal with marginal low level wind shear through daybreak
followed by very gusty winds on Wednesday. Winds should begin to
increase across western Missouri and eastern Kansas through the
night, with kmci (due to it's elevation) likely seeing gusty
conditions. Have maintained low level wind shear at both mkc and stj. Otherwise an
increasing pressure gradient and strong low level jet will allow near Wind
Advisory level winds (30 mph sustained/45mph gusts) to form by mid-
morning Wednesday and continue through mid-afternoon. By 4pm, winds
will begin to subside slightly.
A front will approach the area in the evening with a wind shift to
the northwest after 03z. VFR conditions are expected with this front
and any cloud cover accompanying it.
issued at 406 PM CDT Tuesday Apr 15 2014
As has been the case since late winter the models appear to be over-
forecasting the surface dewpoints. The source region of this dry
airmass, the southern High Plains into western KS, saw dewpoints from
the single digits into the middle 20s. Have gone much lower than
guidance forecast on dewpoints and potential to go even lower.
However, not enough confidence to go to extremes as a strong
southerly surface wind will be trying to draw up modified Gulf
moisture. Late morning/afternoon relative humidity values at or below
25 percent, winds in the 20-30kt range plus native grasses still well
cured for the most part despite the recent heavy rains the County Warning Area could
reach or exceed red flag warning criteria. For now will issue a Fire
Weather Watch and allow the midshift to reassess the need to upgrade.
In addition, many agencies have been doing prescribed Burns today
over the Flint Hills as well as parts of our western cwa, thus
justifying at least the issuance of a watch for Wednesday.
Kansas...Fire Weather Watch from 11 am CDT Wednesday through Wednesday
evening for ksz025-057-060-102>105.
MO...Fire Weather Watch from 11 am CDT Wednesday through Wednesday
evening for moz001>008-011>017-020>025-028>033-037>040-