Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 072111

National Weather Service Topeka KS
311 PM CST SUN FEB 7 2016

.SHORT TERM...(This Evening through Monday)
Issued at 311 PM CST SUN FEB 7 2016

Main upper low continues to sink southeast out of Minnesota with
another wave diving southeast over eastern South Dakota per recent
water vapor imagery. Mid cloud ahead of this feature was through
northern Nebraska with lower ceilings entering this portion of the
state. Pressures were rising quickly behind the second wave with
temps mainly in the 30s and gusts above 40kt common. Winds haven`t
quite reached Advisory levels so far but mixing being maximized at
this time and could yet see at both sustained and gusts values get
into this range over the new few hours.

Cold air advection ramps up tonight as the wave passes but remains
rather dry aloft. Upstream stratus still moves in however with
strong pressure gradient keeping winds up and at least some chance
for mixing into it through the night. Deepest mixing potential still
looking to be during the daylight hours of Monday with 850mb winds
still near 60 kts as boundary layer winds become more aligned with
the winds at this level. Have higher confidence in a widespread
Advisory then, especially for gusts. Could see winds in northeastern
locations near Advisory speeds just before dawn but have too little
confidence in this occurring during this atypical time. Models remain
consistent with minor surface-based CAPE developing via the mixing
and bring various ideas of shower development in the overnight to
midday hours before drying occurs near the top of the mixed layer.
Could see some very light accumulations result, but it continues to
present as more of a rapidly dropping visibility concern given
expected wind speeds.

.LONG TERM...(Monday Night through Sunday)
Issued at 311 PM CST SUN FEB 7 2016

The pattern becomes dominated by a long wave trough over the
eastern half of the country for next week. This is expected to
keep a northwest flow aloft and allow high pressure to
occasionally build south through the plains with the bulk of the
cold air remaining over the upper Midwest. Models show some weak
signs for trace precip events Tuesday night and Wednesday as high
pressure builds through the middle MO river valley. While there is
no significant wave noted in the model progs, there are some bands
of mid level frontogenesis with reasonable saturation in those
levels. However vertical motion does not appear to be very strong
as a result of the frontogenesis. So have kept a dry forecast
going and will watch trends from later model runs. The only other
opportunity for precip looks to be on Sunday. The GFS and ECMWF
have not had the best continuity in the extended periods, and now
they only show an open wave within the northwest flow affecting
the forecast area for the later half of next weekend. In fact the
GFS and ECMWF have trended warmer such that any precip would be
all rain.

In the expected pattern of northwest flow and occasional surface
ridging, a persistent gradient of cool temps over northeast KS to
relatively warmer temps in central KS is anticipated. Models tend
to keep the really cold air to the northeast of the forecast area
and don`t really show any major warm ups for the next week.
Because of this have stayed fairly close to the model consensus
as the forecast area looks to be within the stronger gradient for


.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1146 AM CST SUN FEB 7 2016

VFR conditions should dominate particularly in the first half of
the forecast. Wind speeds are the main challenge with deep mixing
possibly leading to brief strong wind gusts around 20Z and again
late in the forecast. Could have more stronger gusts between 0Z
and 15Z but this appear less common. At least small chances for
brief visibility and ceiling restrictions remain in this same
window with snow shower potential but too little for a mention


.TOP Watches/Warnings/Advisories...
Wind Advisory from 8 AM to 6 PM CST Monday for KSZ008>012-

Wind Advisory until 6 PM CST this evening for KSZ008-020-021-



LONG TERM...Wolters
AVIATION...65 is the U.S. government's official web portal to all federal, state and local government web resources and services.