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Area forecast discussion
National Weather Service Topeka Kansas
1125 am CST Thu Nov 14 2019

Synopsis...
issued at 218 am CST Thu Nov 14 2019

08z water vapor imagery showed a broad upper trough over the
plains and Great Lakes with upper ridging along the West Coast.
Within the trough, one shortwave was moving east through the mid
MS River Valley while a second wave dug south along the central
rockies. At the surface, high pressure was slowly building south
into the Central Plains with a weak frontal boundary across
eastern OK and central MO.

&&

..update to aviation forecast discussion...

Short term...(today and tonight)
issued at 218 am CST Thu Nov 14 2019

For today and tonight, the wave digging south along The Rockies
is progged to remain west of the forecast area leaving subsidence
over northeast Kansas. So dry weather is expected through tonight.
Think there should be some weak cold air advection with the
surface ridge sliding through the state. But this should be offset
by some sunshine by this afternoon. So have kept forecast highs
generally in the mid 40s. Clearing skies and light winds should
allow for temps overnight to fall into the lower and middle 20s.

Long term...(friday through wednesday)
issued at 218 am CST Thu Nov 14 2019

The forecast for Friday through Wednesday remains dry. Although
there remains some opportunity for precip chances, mainly for late
Saturday night and Sunday and possible again Monday afternoon.
Models have trended in keeping an upper trough, expected to move
over the Central Plains on Sunday, more phased with the northern
stream. As a result, vorticity advection and forcing for precip
appear to be better organized as the trough passes overhead. The
GFS even suggests there will be some marginal moisture advection
ahead of the wave. Unfortunately GFS forecast soundings still show
some dry air that needs to be overcome and think this is the
reason for a lack of quantitative precipitation forecast. On the other hand, the European model (ecmwf) and NAM
seem to also be trending towards a little more moisture.
Considered inserting a slight chance pop for this, but the
National blend of models seems to favor a dryer solutions. So have
kept the forecast dry for now and will see how newer model runs
come in. For Monday afternoon and evening, there continues to be a
signal for a low amplitude wave within the northwest flow to clip
northeast Kansas. Models have been a little inconsistent in placement
of some light quantitative precipitation forecast. Think the overall probability for measurable
precip may be around 10 percent so have not mentioned precip
chances in the forecast.

For Tuesday and Wednesday, shortwave ridging is progged to develop.
There are some issues with the models handling the synoptic pattern
by the middle of next week as they show the potential for the
pattern to split with energy cutting off over California. Have not change
the temp forecast to much from the previous forecast. Today looks to
be the coolest of the next seven. Temps look to be closer to normal
through the weekend with highs in the mid and upper 50s and lows in
the 30s. Mild weather is expected to start off next week with highs
in the 60s as heights rise.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1115 am CST Thu Nov 14 2019

High pressure will continue to allow for VFR conditions through
this taf period. Surface winds will turn light and variable around
sunset before increasing tomorrow morning out of the south. Some
steam fog over area rivers and lakes is possible early tomorrow
morning, but that would be unlikely to impact terminals. Thus,
there is no mention of reduced visible in tafs.

&&

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

$$

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