617 
FXUS63 KTOP 190820
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
220 AM CST Thu Dec 19 2019

.SYNOPSIS...
Issued at 220 AM CST Thu Dec 19 2019

08Z water vapor imagery showed an upper low moving towards the 
four corners region with a closed upper low over the Gulf of 
Alaska. Shortwave ridging was noted over the central plains. At 
the surface, a trough of low pressure extened from the norther 
plains south into the southern high plains while weak surface 
ridging remained along the TX gulf coast. 

&&

.SHORT TERM...(Today and tonight)
Issued at 220 AM CST Thu Dec 19 2019

For today and tonight, there is not a lot of change from the 
previous forecast. The upper trough to the west is expected to 
approach the area with very limited moisture available. So the 
forecast continues to call for dry weather. The main question is 
how warm will temps get. With the snow on the ground expected to 
limit mixing once again and some increasing clouds, think highs 
today will only be a few degrees warmer than yesterday in spite of
the southerly return flow pattern advecting warm air north. Have 
highs in the mid 40s where the snow still appeared to be fairly 
deep on satellite and upper 40s where a good deal of the snow had 
already melted. For tonight partly to mostly cloudy skies and 
continued southerly surface winds should keep lows in the upper 
20s to around 30. 

.LONG TERM...(Friday through Wednesday)
Issued at 220 AM CST Thu Dec 19 2019

For Friday and Friday night, some marginal moisture is progged to
move into eastern KS, but by this time much of the forcing from 
the developing closed low is expected to have shifted east. By 
Saturday the forecast area is progged to increasingly be under the
influence of an upper ridge. This ridging is forecast to persist 
into the first part of next week. For the middle of next week, 
there is increased uncertainty in the forecast due to some model 
variability. Specifically the GFS has trended faster with a lead 
wave lifting out of the western upper trough. Meanwhile the ECMWF 
is much weaker with any initial wave and about 18 hours slower 
with its progression. So while there remains some signal for POPs 
in the Tuesday night to Wednesday time frame, the discrepancies 
make it hard to go with anything more than a slight chance at this
point.

Models show a good warm air advection pattern developing for the 
weekend and into next week. By this time it is expected that snow 
will have little to no impact on temps so have continue with a 
warming trend and bumped highs up for Sunday and Monday when temps 
could warm into the mid and upper 50s. 

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1121 PM CST Wed Dec 18 2019

VFR conditions are expected through the TAF period. LLWS
conditions will persist through 12-14Z as a 40-45 kt LLJ at
800-1000 ft remains over the area. Southerly winds will remain 
predominately below 10 kts through the period. Lastly, marginal
LLWS conditions are possible near the end of the TAF period at all
sites. 

&&

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

$$

SYNOPSIS...Wolters
SHORT TERM...Wolters
LONG TERM...Wolters
AVIATION...Baerg