Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 242021

321 PM CDT Sun May 24 2015

.SHORT TERM...(This Evening through Monday)
Issued at 243 PM CDT SUN MAY 24 2015

The forecast issue tonight is how much rain will fall on the
flooded areas in the southeast part of the forecast area. At 19
UTC, a large-scale upper trough was moving northeast out of the
southern plains. The 12 UTC short-range models were in decent
agreement with the progression of the precipitation this evening.
Heaviest rainfalls should fall across Missouri sparing eastern
Kansas of heavy rainfall. However, it appears likely that a band
of showers and isolated thunderstorms should move through this
evening. The latest HRRR is consistent with previous runs in this
scenario as are the rest of the convective resolving meso-scale
models. Although widespread heavy rainfall is not expected, it
would not take much rainfall to cause more flooding problems.
Therefore, we will keep the flash flood watch going and we can
cancel it early if necessary.

Additional thunderstorms are developing over southeast Colorado
which the hi-res NAM brings east into our west counties late
tonight. Keep a small POP going along with clouds late tonight and
Monday morning.

Both the 12 UTC NAM/GFS bring an EML into northeast KS in the wake
of the ejecting upper trough. Model soundings suggest a decent
cap over the area on Monday with more than modest surface based
CAPE by afternoon. On the synoptic scale, a shortwave should once
again be moving through the southern plains, but it should be too
far south to impact our weather. Meanwhile, the models develop
convection near the synoptic boundary over parts of central KS/NE.
Will keep pops going for late afternoon development over our
northwest counties. The GFS has a deeper 500 mb low over the
central plains by next Sunday while the ECMWF is not as deep and
more progressive.

.LONG TERM...(Monday Night through Sunday)
Issued at 243 PM CDT SUN MAY 24 2015

The weather pattern remains unsettled through the forecast period
and we will have thunderstorms chances almost every period. The
large upper trough over the desert southwest slowly moves into the
central plains during the period. The 12 UTC ECWMF/GFS agree
with the general progression, but there are significant differences
in the details. At the surface, there will be a boundary in the
vicinity which will be heavily influenced by mesoscale influences.
Meanwhile, the Gulf of Mexico will remain open for business with
moisture advection into the central Plains. Will keep
thunderstorms chances going with more humid and warm weather close
to seasonal normal`s.


.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1245 PM CDT SUN MAY 24 2015

Today and early evening, there are a couple mid-level shortwaves
that will impact the TAF sites. Much of this activity will be in
the late afternoon and early evening with the possibility of some
thunderstorm activity developing which could bring some periods of
low end MVFR CIGS/VIS to the terminals. Outside of this, there are
some spotty areas of light showers right now. Not completely
confident any of these will impact the terminals. Therefore, have
left only VCSH for both the afternoon and then again a chance in
the early morning. Lower confidence on the morning showers. But again,
generally expecting VFR outside of some brief periods with the thunderstorms.


FLASH FLOOD WATCH through Monday morning FOR KSZ026-039-040-



SHORT TERM...Johnson
LONG TERM...Johnson
AVIATION...Drake is the U.S. government's official web portal to all federal, state and local government web resources and services.