866 
FXUS63 KTOP 201738
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1238 PM CDT Sat Oct 20 2018

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 216 AM CDT Sat Oct 20 2018

07Z water vapor imagery showed an upper low over western Ontario 
with one shortwave rotating across Lake Huron and a second shortwave 
digging through southern MN. A broad upper low was noted off the 
coast of southern CA with ridging over the northern Rockies. At the 
surface, high pressure was building south along the lee of the 
Rockies and much dryer air was moving in with the surface ridge. 

The forecast for today and tonight is for clear skies and dry 
weather due to a lack of forcing over the central plains and a dry 
airmass moving in. Cold air advection through the day is expected to 
keep highs cooler. But forecast soundings do show mixing to 850MB 
and good insolation may offset the cold air advection somewhat. 
Think highs will range from around 60 to near 65 degrees. The center 
of a high pressure system is progged to move across northeast KS 
tonight. With the boundary layer decoupling and clear skies 
providing a good setup for radiational cooling, have trended lows a 
few degrees colder into the upper 20s across northeast and east 
central KS where winds are likely to remain light. Lows are forecast 
to be in the mid 30s across north central KS where the light winds 
may be more temporary as the center of the high passes east quickly.

.LONG TERM...(Sunday through Friday)
Issued at 216 AM CDT Sat Oct 20 2018

Transitioning into the extended period, a predominately quiet and
seasonable forecast is expected into the middle of next week. A
shortwave trough is progged to translate southeastward across the
Great Lakes region Monday afternoon -- shunting a weak surface 
trough axis through the CWA. Little moisture is expected to reside
along the boundary, as a result precipitation is unlikely. Ahead 
of the front Sunday afternoon, southerly winds may gust up to 25 
MPH. 

The broad upper low currently off the coast of CA is progged to be
absorbed within the upper flow and traverse the central Plains
Wednesday into Thursday. Scattered, light rain showers are
probable Wednesday afternoon/evening, although a substantial dry 
layer beneath 10kft should limit rainfall efficiency with
accumulations predominately less than 0.1". The midlevel ridge 
axis is progged to re-amplify across the western US by the end of
next week. Additional rain showers are possible Thursday into 
Friday as a shortwave trough traverses portions of the mid-MO 
river valley.

In regards to temperatures, the entire period is likely to see
near-normal or slightly below-normal temperatures. High
temperatures are expected to range from the upper 50s to the
middle 60s with lows in the low to middle 40s. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1227 PM CDT Sat Oct 20 2018

For the 18Z TAFs, VFR conditions will be the rule. Winds decrease
by late afternoon near KTOP/KFOE as the gradient continues to
relax. Surface ridge expands over the area tonight and then return
flow gradually develops by morning with winds veering from the
southwest. 

&&

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

$$

SHORT TERM...Wolters
LONG TERM...Baerg
AVIATION...Drake