566 
FXUS63 KTOP 012027
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
327 PM CDT Mon Apr 1 2019

.SHORT TERM...(This evening through Tuesday)
Issued at 325 PM CDT Mon Apr 1 2019

Aside from a slight chance of showers along the Nebraska border 
tonight, expect seasonal and dry weather conditions for tonight 
and Tuesday.

Broad longwave ridging spanned the eastern two-thirds of the 
CONUS this afternoon with a well-defined shortwave trough/cutoff 
low progressing through the Ozarks. Subsidence behind this trough 
as noted in water vapor imagery cleared out skies over the 
forecast area this afternoon, but return flow and deeper moisture 
were already working into western and north-central Kansas as 
evident by the development of a CU field with peak heating this 
afternoon. This deeper moisture works into the eastern part of the
state tonight ahead of a weak H500 trough axis currently along 
the Wyoming/Nebraska border. A weak surface baroclinic zone will 
likewise slide from central Nebraska to near Topeka by 12Z and 
decays during the day on Tuesday. 

Surface to H850 frontogenesis wanes as the boundary approaches 
the area, but some residual showers are possible along the 
Nebraska border tonight as this band of forcing moves through. 
Depending on the strength of the warm nose and mid-level lapse 
rates, there is a non-zero chance that MUCAPE values could exceed 
100 J/kg with the EL around -20 to -25 C. Therefore, did mention a
slight chance of thunderstorms in the forecast, but the likelihood
of there being even showers, much less thunderstorms, is quite 
low. Dry sub-cloud layer profiles will promote efficient 
evaporation of any precip generated in the H800 to H700 saturated 
layer, limiting the degree of any precipitation reaching the 
surface.

For Tuesday, surface high pressure builds into the area on the 
heels of the departing trough and will result in light winds and 
seasonal temperatures for the daytime hours with little in the way
of CAA in the lower troposphere behind the departing boundary.

.LONG TERM...(Tuesday night through Monday)
Issued at 325 PM CDT Mon Apr 1 2019

Several rounds of precipitation are forecast for mid-week and
again this weekend with temperatures fluctuating around normal for
this time of year.

The upper level pattern amplifies Tuesday night ahead of an
approaching shortwave/PV lobe ejecting from a quasi-stationary low
along the coast of British Columbia. Increasing theta-e advection
ahead of this trough--coupled with modest isentropic ascent--could
fuel showers Tuesday night into Wednesday, with a strong EML 
limiting any thunderstorm potential. Highs on Wednesday will 
depend on the exact location of the developing warm front with 
some variability noted in the short to medium range guidance in 
its exact placement. Most of the forecast area should reside in 
the warm sector, promoting highs in the low to mid 60s despite 
ample mid to high cloud cover. 

As the H300 trough digs southeastward, the surface cyclone 
reflection also pulls southeastward and drags the now inverted 
surface trough through the forecast area through the day on 
Thursday. Multiple rounds of showers and thunderstorms are likely 
along this boundary, but deep shear profiles will not be 
conducive for any organized thunderstorms with the main jet 
displaced over the Southern Plains. Highs will be tempered on 
Thursday given the ample clouds and precipitation, but will be 
quick to recover by Friday and Saturday under a progressive flow 
pattern that will promote the return of +12 to +14 C H850 air for 
the weekend, resulting in highs in the 60s and even 70s during 
this time. Confidence in the timing and characteristics of our 
next disturbance over the weekend is low at the present time, but 
do expect that there will be precipitation at some point during 
this time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 100 PM CDT Mon Apr 1 2019

VFR conditions are expected for the TAF period with southwesterly
winds backing to the north overnight. There is a slight chance of
showers and possibly a thunderstorm along the KS/NE border
overnight tonight.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Skow
LONG TERM...Skow
AVIATION...Skow