Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

560
FXUS63 KEAX 221027
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
427 AM CST Thu Feb 22 2018

.Discussion...
Issued at 426 AM CST THU FEB 22 2018

The wintry precipitation continues this morning across much of the
forecast area, with freezing rain and some wintry mix being
reported south of HWY 36 and snow/sleet north of HWY 36. Those
north of HWY 36 should see a change over to freezing rain near
dawn as cloud ice introduction decreases. The precipitation will
continue through the morning hours before lifting north. Between a
tenth and two tenths of an inch of ice is expected. A short break
in the precipitation is then expected across much of the forecast
area late morning through early afternoon, but can`t rule out
some patchy drizzle/freezing drizzle. Temperatures are expected to
warm more than yesterday, but there is some uncertainty to how
warm we get. In general, models bring those in central MO to the
low 40s, with areas west reaching the mid 30s. While it is not
totally out of the realm of possibilities, it doesn`t seem likely
due to the easterly surface wind, cloud cover, and the
ice/snow/sleet accumulations. Therefore, have cooled temperatures
during the day today a few degrees. With that said, our southern
third of counties could still see a change over to rain late this
morning before the precipitation moves out.

A second round of precipitation, if you will, is expected to move
north into the area later this afternoon, but by the time this
occurs, most of the forecast area temperatures should be above
freezing, with the exception of our northwest corner and northern
tier of counties. In these areas, freezing rain will be the
primary precip type, but temperatures will actually continue to
increase for the first part of the night due to WAA, so some
liquid rain will eventually start to mix in. With the expected
continuation of freezing rain in these areas, the Winter Weather
Advisory now goes until midnight Friday morning. The
precipitation should exit the area early Friday morning.

This weekend, the upper level trough that is currently over the
Pacific Northwest will move through the Plains providing upper-level
support for more precipitation. At the surface, a lee-side trough
will take shape and move a warm front and then a cold front
through the area. While there are a few differences between the
NAM, GFS, and ECMWF, they all show this system having strong
dynamics with the upper-level trough taking on a negative tilt as
it passes overhead. This and the robust surface low bringing
ample moisture and instability could lead to storm development,
and potentially strong storm development. The system is scheduled
to move out of the area Sunday morning, with high pressure moving
in behind. The high pressure should keep us dry for the early part
of next week.


&&

.Aviation...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1113 PM CST WED FEB 21 2018

A weather system will be pushing into the area with a mix of
precipitation with mostly freezing rain, freezing drizzle, and
ice pellets south of the Missouri River and snow to ice pellets
north of the River. KMCI will be right on that line with mostly a
mix of ice pellets and snow transitioning to all freezing rain by
8-9Z. This freezing rain looks to last 4-5 hours and may cause
issues in the morning with take off and landing. This will
basically be the case with all the airfields in the morning
timeframe until the system pushes out around 14-15Z. A total of
between 0.05-0.1 inches of ice accumulation are possible for the
southern terminals with more snow and ice pellet accumulation to
the north. To go along with this wintry mix of precipitation will
be an IFR ceiling that will reside from around 8-9z until the end
of the period. Ceilings look to lower slightly at the end of the
period and may result in some of the airfields beside KMCI going
into an alternate minimum category. A second round of
precipitation is expected to push into the region around 21z and
surface temperatures will drive what type of precipitation falls.
It looks like the freezing line will push just north of KMCI,
leaving everything south to be rain while everything north will be
freezing rain. If this freezing line shifts south then
precipitation would result in freezing rain. With only one or two
degrees making the difference this period will be monitored and
updated with the latest temperature forecast in subsequent
forecasts. Ceilings will drop below alternate minimums between
00-03z which will last through the end of the period.


&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...Winter Weather Advisory until noon CST today for KSZ057-060-
     103>105.

     Winter Weather Advisory until midnight CST tonight for KSZ025-
     102.

MO...Winter Weather Advisory until noon CST today for MOZ017-021>025-
     028>033-037>040-043>046-053-054.

     Winter Weather Advisory until midnight CST tonight for
     MOZ001>008-011>016-020.

&&

$$

Discussion...Grana
Aviation...Barham



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.