Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 241734

Area Forecast Discussion
National Weather Service Topeka KS
1234 PM CDT Tue Apr 24 2018

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 258 AM CDT Tue Apr 24 2018

Early this morning, the surface and mid-level lows were situated
over the Dakotas, with a cold front extending southward into
Nebraska and far northwest KS. As of 08z, water vapor imagery
showed mid-level clouds tracking into portions of north central KS
ahead of the cold front. By sunrise, expect the cold front to be
shifting eastward into north central KS, with the boundary likely
bisecting the CWA by early afternoon. With this frontal passage
today, mid-level clouds will gradually overspread the area from
west to east from mid morning through late afternoon. Despite this
advancing cold front with light northerly winds behind it, models
show a lag in this northerly flow ushering cooler air into the
region. As a result, short-range models show temperatures quickly
rising this morning with highs in north central KS likely managing
to rise into the mid/upper 60s. Further east, have trended a bit
warmer with highs reaching into the low/mid 70s.

Cooler air won`t be the only thing lagging behind the frontal
passage, as the associated precipitation chances with this system
also are continuing to trend slower amongst the models. Model
soundings show increasing mid-level clouds with the advancing cold
front, however there will likely be plenty of low-level dry air that
will need to be overcome.  As a result, have a dry forecast through
the morning hours with scattered rain showers likely tracking
eastward across the area this afternoon through the overnight hours.
These scattered rain showers may come in two batches: one tracking
across northern KS along the northern edge of the advancing mid-
level low, and the second associated with the better moisture and
lift over central to south central and southeast KS.  Despite the
best moisture/lift likely tracking along and south of the southern
edge of the CWA late tonight through the overnight hours, models
show enough isentropic lift present to likely result in widely
scattered showers across much of the outlook area overnight into
Wednesday morning.  Overcast skies from the scattered showers will
likely keep low temperatures tonight in the mid/upper 40s and
possibly even low 50s over far eastern KS.

.LONG TERM...(Wednesday through Monday)
Issued at 258 AM CDT Tue Apr 24 2018

Chances for precipitation look to be increasing into Wednesday as
the upper trough continues southeast across central portions of the
state. Models are in good agreement with the low slightly deepening
in the afternoon and evening, but differ on location of deeper
moisture and forcing. Raising precip chances seems in order, though
not confident enough on coverage across the entire area for anything
above likely range yet. Have also trended temperatures down along
the lines of the wetter solution. Precip amounts also trending up,
but event totals over an inch should be the exception.

Next wave still to follow fairly closely behind, passing Thursday
afternoon and evening. This weaker, open wave keeps coverage of
precip more in doubt, but slightly better low-level moisture
potential could lead to a few thunderstorms, mainly in the evening
as moisture improves with time. Most locations should remain in the
warm sector through the day with highs back in the mid to upper 60s,
with little change Friday as modified high pressure moves in.

The weekend periods begin a transition from northwest flow to
southwest flow aloft as the upper trough off the west coast enters
the CONUS. A warmer and breezier forecast is in order, though have
uncertainty in how fast the trough will push toward the Rockies in
split flow, potentially leaving the trough cut off to the west
through Monday. Precipitation chances remain very low for Friday


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1231 PM CDT Tue Apr 24 2018

Scattered rain showers are expected later this afternoon and into
the evening. The ceilings should remain VFR until around midnight
or shortly after. There is a chance for brief MVFR ceilings during
the 00-06Z time frame. After that there is pretty good agreement
for prevailing rain through the taf period with ceilings going to
IFR by towards late tomorrow morning.




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