Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO
FXUS63 KEAX 262033
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
233 PM CST Sun Feb 26 2017
Issued at 233 PM CST SUN FEB 26 2017
The forecast over the next few days is going to vary greatly in
time and area. Temperatures tonight will fall into the 20s and
30s, but we`ll warm up into the 50s and 60s as a warm front lifts
north into the area. This front may spread some showers across the
area and will also lead to higher humidity as a surge of
relatively warm dewpoints moves northward behind the front.
Heading into Tuesday, winds will veer to the southwest ahead of an
approaching cold front and in the vicinity of a pre-frontal trough.
Forecast soundings continue to show deep mixing in a corridor along
the trough and as a result dewpoints drop considerably during the
afternoon. It continues to look like at least very high fire
danger will develop over portions of east central KS and west
central Missouri, where the deep mixing scours out dewpoints and
transports strong winds aloft to the surface. While there is a
chance for showers and thunderstorms, mainly in our
southern/southeastern zones during the day, the chance for
precipitation looks much greater in the post-frontal cold
advection regime late in the evening and overnight. During the
day, while instability develops in our southeast, winds are veered
to the southwest and there is little convergence along the pre-
frontal trough. Forecast soundings in this area show 500 to
perhaps as much as 750 J/kg MUCAPE. But there also remains some
inhibition to overcome and with little forcing think that it`s
more likely we`ll go through the day with little/no convection.
Once the front moves through though during the evening/overnight
hours, the mid and upper levels begin to cool and saturate with
some elevated moisture present above the inversion. So it looks
more likely that showers and a few storms will develop over the
area during the evening and overnight hours. Strong shear will
remain in place given the fast moving mid to upper flow so a few
strong thunderstorms are possible.
The other aspect of this system is how quickly cold air funnels into
the area, enabling snow to develop. Available models all generate
some snow as the main PV anomaly approaches the area. The NAM is the
most robust, laying down several inches across northern Missouri.
The ECMWF, GFS and the Canadian are much less robust, despite a
similar upper pattern. The main distinguishing feature with the NAM
is the intensity of a frontogenetic band with the passage of the mid-
level shortwave and the maximum lift in the snow growth region. The
finer resolution of the NAM combined with its stronger forcing seems
to be the culprit for its much higher snow amounts. That said, given
the synoptic scale agreement with coarser scale models, feel this
period will need to be watched for potential wintry weather.
The remainder of the forecast looks quiet with split flow
encroaching on or over the region. This pattern should keep us
slightly above normal through the end of the work week but as flow
becomes more persistently out of the south/southwest, much above
normal temperatures are expected for next weekend.
.Aviation...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1106 AM CST SUN FEB 26 2017
With precip moving away/diminishing, VFR conditions are expected
through the forecast. Winds will back to the southeast through the
period but remain light.