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Area forecast discussion
National Weather Service Topeka Kansas
630 PM CDT sun may 28 2017

..update to aviation forecast discussion...

Short term...(this evening through monday)
issued at 239 PM CDT sun may 28 2017

As of 19z a closed upper low continues to spin across the Great
Lakes region. At the surface, high pressure continues to build in
across the Central Plains. Sunny skies will continue through the
remainder of the day with high temperatures reaching the lower 80s!
A weak surface front will sag southward through the outlook area
late tonight/early Monday morning. Decent mid level frontogenesis
and saturation will be coupled with the front which could result in
a few rain showers especially along the Kansas/NE border. However, a dry
boundary layer is expected, therefore expect the majority to remain
as virga or a few sprinkles. Low temperatures will drop into the
middle 50s tonight. Winds will remain out of a northerly direction
throughout Memorial Day. Temperatures will remain quite pleasant
however, with highs approaching 80 Monday afternoon!

Long term...(monday night through sunday)
issued at 239 PM CDT sun may 28 2017

On Tuesday morning the weak front will be stalled out over portions
of southeast and central KS, which will be the focus for showers and
maybe a few storms. These showers may linger into the afternoon as
that boundary remains fairly stationary. At the same time a weak
shortwave will push another boundary southward during the afternoon
and evening. Models are depicting a weak cap in place therefore
surface heating and minimal forcing along the front will result in
showers and storms. The northwest flow aloft is contributing to deep
layer shear around 40 to 50 kt. Depending on the residual low level
moisture left behind the previous front cape along with the shear
could be enough to support stronger updrafts. The main question will
be the quality of the moisture return in the short time return flow
can get established ahead of the front. The consensus for the
highest MLCAPE values on Tuesday afternoon is around 2000 j/kg,
which is in response to dew points around 60. Surface high pressure
will build into the central US on Wednesday, which reinforces the
return flow across the area. Within this pattern the models are
depicting some sort of mesoscale convective system developing in NE and progressing eastward
Wednesday night. This mesoscale convective system or associated outflow could push into far
northeast Kansas resulting in the development of showers and storms.
Thursday and on an upper level low lifts out over the Southern
Plains. This will place the forecast area in between this low and
northwest flow aloft. As the low weakens into an open wave and
becomes absorbed into the northern stream precipitation chances
increase for the weekend.

&&

Aviation...(for the 00z tafs through 00z Monday evening)
issued at 626 PM CDT sun may 28 2017

VFR conditions persist for the forecast period. A weak cold front
sags south into the terminals. Could be enough lift in the low to
mid levels to see a few sprinkles fall out of scattered deck. Have left
out of tafs due to low probability near the 12z time frame.

&&

Top watches/warnings/advisories...
none.
&&

$$

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