419 
FXUS63 KEAX 050441
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1041 PM CST Thu Jan 4 2018

.Discussion...
Issued at 255 PM CST THU JAN 4 2018

Mid-level clouds have streamed into much of the forecast area, and 
with surface high pressure nearby with little advection, a chilly 
airmass has remained in place. Lows tonight will remain below 
normal, but a few degrees warmer than minimum temperatures last 
night. Winds will also remain light, becoming easterly, keeping wind 
chill values far from dangerous levels. An embedded wave within the 
northwest flow aloft allowing for vertical saturation to occur in 
the vicinity of decent frontogenetical forcing centered at H8 will 
result in a band of snow likely to evolve over northeast Missouri 
this evening into tonight. Current radar reflectivity shows an 
expansion of echoes across central Iowa into northern Missouri, 
presently in the form of virga. Cloud bases have been running around 
6-10kft, and light snow is currently reaching around 3kft AGL before 
sublimating. Expect further saturation in the low levels to occur, 
with light snow reaching the surface by this evening. Total snow 
amounts in the far northeastern CWA will average a couple tenths of 
an inch of snow, to a little more than one-half inch in Schuyler 
County. 

A thickish cirrus canopy is expected for Friday, keeping the 
strongest surface heating at bay. Rising heights and an evolving 
warm front will result in modest temperature gradient across the CWA 
Friday through Saturday. Highs over northeast Missouri will remain 
in the teens, in part thanks to the anticipated new snow cover from 
tonight, to the lower/middle 30s over east central Kansas into west 
central Missouri. Wind chills may be of concern Saturday morning 
over northeast Missouri, with feel like temperatures around 15 below 
zero.

A weak shortwave trough will come on shore in the Pacific northwest 
and glide southeastward within the northwest flow toward the 
forecast area. With decent moisture advection, the shortwave should 
bring enough ascent to get some light to perhaps moderate rain at 
times on Sunday. Overnight lows on Saturday night into Sunday 
morning should be below freezing, so the initial isentropically 
ascended warm-air advection precipitation on Sunday morning may come 
in the form of mixed wintry precipitation. Dry air in the mid levels 
and a warm nose indicated by GFS soundings would conceive an idea 
that ice particles would have a hard time surviving to the surface, 
so freezing rain or sleet could be possible early Sunday morning. 
Best chance for this freezing precipitation would be across far 
northeastern Missouri, where temperatures will linger the coldest. 
South of of I-70 overnight lows should stay in the upper 20s, so the 
warm air advection should get temperatures above freezing pretty 
quickly. Even as temperatures warm above freezing, sheltered or 
shaded areas could see slick spots during the morning hours during 
the initial bout of precipitation. 

A warmup commences early next week with temperatures finally 
reaching to above normal levels with highs in the middle 30s to well 
into the 40s. Dry weather is anticipated until the next storm system 
arrives middle/late in the work week, bringing more active weather. 
The type of precipitation and timing are still evolving and details 
will improve as better sampling occurs. 

&&

.Aviation...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1041 PM CST THU JAN 4 2018

VFR conditions are expected to continue through the TAF period.
Winds will gradually turn from southeast to east-northeast during
the overnight hours, increasing to sustained speeds around 10 kts
by mid-morning.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&

$$

Discussion...Blair
Aviation...Laflin