580 
FXUS63 KEAX 062137
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
337 PM CST Sun Jan 6 2013

.DISCUSSION...

Short Range (Today through Tuesday)...

Main forecast issues for the week currently look to be restricted to 
Wednesday and the days beyond, leaving the beginning of the work 
week rather quite. 

A cool surface high sliding across the region continues to push 
its way across the Lower Missouri River Valley. This has kept 
conditions across the region near seasonally normal under clear 
skies. Surface high will continue its march east overnight, putting 
eastern Kansas and western Missouri on its backside for Monday. 
Southerly return flow behind the surface ridge will help lift 
temperatures back above normal. Have modified the going forecast 
temperatures to reflect some of the lingering snowpack across areas 
of northwest, central and northeast Missouri, though only by 
shaving a degree or two off. Otherwise for Monday, expect winds to 
come up some on the back side of the high as 925mb winds will be 
ranging between 25 to 30 knots as boundary layer mixing kicks in 
after sunrise. 

Tuesday...temperatures will climb a little more (50s south of the MO 
River) ahead of a surface trough that will swing through Tuesday 
night. This will help set the stage for moisture return later in the 
week as a cutoff low lifts out of northern Mexico. 
 
Cutter


Medium Range (Wednesday through Sunday):

Medium range models now handling mid week closed/cut-off upper low 
better. Now appears the 00z ECMWF was an outlier and way too slow. 
12z ECMWF is now more in line with latest GFS, at least through 12z 
Thursday. 12z GFS, while the most progressive, has slowed down some 
while the ECMWF has sped up enough that confidence is relatively 
high on overall forecast through Thursday. That being said cannot 
rule out ensuing model runs will slow system down some more due to 
it being cutoff from the mean flow. Have continued the trend started 
yesterday and slow down the arrival of precipitation and strip it 
out entirely from Wednesday. Thursday still looks like the best bet 
for widespread precipitation. Thermal profile continues to favor all 
rain through Thursday. 

Attention then turns to the weekend system which previously had poor 
model agreement. However, the 12z model runs have trended towards 
more of a consensus with the ECMWF showing the greatest overall 
change. The ECMWF has sped up the arrival of the next system into 
the western CONUS and now shows a negatively tilted shortwave 
rotating through the base of the mean upper trough Friday 
night/Saturday. This is very similar to what the GFS developed on 
yesterday's run and continues with today's 12z run. With an overall 
positive tilt to the main upper trough the frontal boundary 
stretching from the central High Plains into the western Great Lakes 
will likely move little until the negatively tilted shortwave 
mentioned above passes by. This will keep the CWA within the warm 
sector, and much above average temperatures, through at least the 
first half of Saturday. Precipitation chances will be kept low due 
to the uncertainty of timing the shortwave and proximity of the 
frontal boundary. As it currently stands Friday looks to be a day 
between systems and could very well end up being dry.

MJ


&&

.AVIATION...

For the 18Z TAFs...With a cool surface high sliding across the center
of the nation today through Monday, expect VFR conditions to prevail
at the terminals. Exception might be early morning fog in KSTJ, but
at this time it looks unlikely. Otherwise, winds will come around to
the south overnight and become rather gusty as the high moves to our
east Monday morning. 

Cutter

&&

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

$$

WFO EAX