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Area forecast discussion 
National Weather Service Topeka Kansas
1132 PM CST Tue Nov 25 2014

..update to aviation forecast discussion...

Short term...(this evening through wednesday)
issued at 237 PM CST Tuesday Nov 25 2014

Next shortwave to affect the forecast area is dropping quickly
southward out of the Dakotas toward the Missouri River Valley.
High clouds have started to move into eastern Kansas, much of which
has been almost 50 degrees this afternoon.

For tonight, the quick clipper brings a fast chance for some
showers across mostly the north and eastern portions of the
forecast area. Soundings suggest column needs to saturate first
before bringing showers to the ground, and as it does so, wet bulb
effect may be enough to mix snow with rain showers. Not
anticipating accumulation, and band should slide from north
central Kansas and northern Kansas in the late evening then across
far eastern Kansas around midnight through a few hours after. By
sunrise expect band to be east of the forecast area, with breezy
northwest winds in its wake. Highs should be a little colder
thanks to the cooler air with this system, with highs in the upper
30s to low 40s.

Long term...(wednesday night through tuesday)
issued at 237 PM CST Tuesday Nov 25 2014

Extended forecast remains dry while a series of disturbances will
fluctuate temps throughout.

The shortwave trough mentioned earlier quickly deepens as it races
east towards the eastern coast Wednesday evening. Ridging builds
over the western Continental U.S. As surface high pressure spreads over the
plains region. For Thanksgiving day, winds starting off light shift
towards the south at 10 mph by the afternoon. Thermal ridge builds
as warmer air advects into western KS, while influence from the
passing high pressure will hold highs into the lower and mid 40s. By
Friday, upper pattern shifts as a a shortwave trough deepens over
the northern conus, and a surface trough develops over the western
High Plains. Southwesterly flow edges thermal ridge into our area as
highs peak into the 50s, perhaps low 60s. Disregarding the outlier
and faster timing of the cold front seen with the GFS, highs stay in
the 60s for Saturday as the boundary approaches from the northwest.
Gulf moisture begins to spread northeastward, just south and east of
the area. A few model solutions are hinting at spotty quantitative precipitation forecast amounts
for far east central KS, unfortunately dry mid level air spreads
quickly behind the front and will maintain a dry forecast on Sunday.
More importantly are temperatures falling Sunday afternoon into the
middle 30s. This airmass does not stick around however as winds veer
and increase from the southwest once again Tuesday with highs
rebounding into the 50s. As this occurs, model guidance is similar
in a deeper longwave trough slowly building over the southwest
conus, bringing precip chances back into the forecast perhaps as
early as Tuesday evening.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1128 PM CST Tuesday Nov 25 2014

A cold front will move through taf sites between 07z and 09z with
winds shifting out of west and light precipitation expected for 1
to 2 hours...probably rain but some chance for light snow/sleet.
Winds then turn out of the northwest shortly after sunrise with
gusts increasing to 25-30 kts at times. Also expect a period of
MVFR cigs from around 14z through late morning or early afternoon
when cloud bases gradually mix out or lift above 3000 feet.


Top watches/warnings/advisories...


Short term...67
long term...Bowen

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