Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 222340

Area Forecast Discussion
National Weather Service Topeka KS
640 PM CDT Sun Apr 22 2018

Issued at 250 PM CDT Sun Apr 22 2018

19Z water vapor imagery shows a closed upper low over the Ozarks
while the surface low associated with this was over the lower MS
river valley. Radar and satellite showed moisture from the low
pressure system was continuing to rotate into eastern KS. Further
west, an area of low pressure was noted over the desert southwest
and a better defined shortwave was located over the Pacific


...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Monday)
Issued at 250 PM CDT Sun Apr 22 2018

For tonight and Monday, the forecast is for the weather to
continue to dry out. The general consensus is that as the upper
low continues to drift east any forcing for precip will come to an
end with general subsidence increasing. There may be some
sprinkles linger across east central KS through the evening, but
measurable precip looks unlikely.

Clouds could make overnight lows tricky as some models show the
potential for mid level clouds holding on across eastern KS. Where
skies are more likely to clear out, have lows in the lower 40s
across north central KS with mid and upper 40s across eastern KS
where the cloud cover may hang on. Models mix the boundary layer
pretty deep on Monday in spite of a weak ridge axis over the
region. Because of this and with more insolation with the higher
sun angle, trended highs up a degree or two expecting most areas
to reach the lower 70s.

.LONG TERM...(Monday night through Sunday)
Issued at 250 PM CDT Sun Apr 22 2018

There continues to be a couple chances for rain through the mid
week. For Tuesday afternoon through Wednesday, there remains some
uncertainty in how the shortwave energy will evolve as it moves
through the plains. Nevertheless most guidance shows a slower
progression to the wave whether it is opened or closed. Because of
this have a chance for rain through the day Wednesday. Don`t have
much confidence in including likely POPs just yet given the
varying solutions with the energy and trying to highlight one
period with a better chance than another. Models do not show much
if any instability developing with the system so will not include
a mention of thunder in the forecast. Most of eastern KS looks to
remain mild Tuesday with highs reaching the lower 70s, but there
could be a good gradient in highs as the wind shift and increasing
clouds move into north central Kansas through the day. So think
highs will be in the 60s for areas west of Manhattan. Wednesday
could end up being another cloudy and cool day with scattered
showers. So highs are held down into the upper 50s and lower 60s.

For Thursday and Thursday night, models continue to indicate
another shortwave will move through the northwest flow and
potentially amplify as it move across the central plains. The
ECMWF and Canadian show light QPF with the frontal passage, but
the GFS remains dry. There are even some timing difference between
the ECMWF and Canadian. So only have some slight chance POPs for
now, but think there may eventually be a better chance Thursday
afternoon and evening. Hopefully models will start to converge on
a common solution soon.

Upper ridging is progged to develop for Friday through Sunday.
Because of this will keep a dry forecast with warmer temps. The
GFS does show some elevated convection developing within a warm
air advection pattern Saturday night. However it is not supported
by the ECMWF and Canadian, and I think it may be because it is
less amplified with the shortwave Thursday night. Given the recent
trends have been for slower solutions to the waves, think the GFS
may be a little early with return flow Saturday night and will
keep the forecast dry for now.


.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 635 PM CDT Sun Apr 22 2018

VFR conditions persist this forecast period as clouds generally
decrease and a dry airmass settles completely into the region.




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