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

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
804
FXUS63 KEAX 181718
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1118 AM CST Wed Jan 18 2017

.Update...
Issued at 1117 AM CST WED JAN 18 2017

The 12Z TOP sounding shows a strong inversion with low level
moisture trapped underneath it. Forecast soundings across the area
suggest some improvement in the fog based on limited mixing of the
boundary layer but low clouds likely lingering through the
afternoon for those areas that are already socked in. This is
especially the case the further east into the clouds on goes. Have
updated the forecast to increase the cloud cover substantially
this afternoon. This also has the effect of dropping temperatures
due to lack of insolation. So have dropped temperatures into the
mid to upper 40s.

Update Issued at 428 AM CST WED JAN 18 2017

Given an expansion of reported 1/4 mile visibilities across the
area, have issued a Dense Fog Advisory through 9 AM for areas
across eastern Kansas and western Missouri. Areas of freezing fog
may form slick spots on elevated surfaces Wednesday morning.

&&

.Discussion...
Issued at 329 AM CST WED JAN 18 2017

Low level stratus has been slow to advect eastward through early
Wednesday morning. Areas of clearing remain mostly west of I-35,
with resulting fog having quickly formed from radiational cooling. A
mid-level cloud layer approaching from the southwest, now as far
north as much of central Kansas, will continue to mitigate dense fog
potential as it pushes northeast through the morning. Have thus held
off on a Dense Fog Advisory given the expected patchy nature of fog
potential. Areas of freezing fog have been observed across eastern
Kansas and western Missouri, which may present the possibility of
slick spots on elevated surfaces during the morning commute. Fog is
expected to erode by the mid-morning hours with daytime heating.

A broad trough over the southwestern CONUS will lift northeast
through the morning and eventually provide steady southwest flow
aloft by the afternoon. This will help to erode lingering cloud
cover and push high temperatures for Wednesday above 50 degrees for
most areas and temps in the upper 40s for areas across north
central to northeastern Missouri. This warming trend will remain
in place as warm advection continues until next week. Overnight
lows through this period will also remain above freezing for most
areas until late in the weekend.

As the southwestern trough lifts northeast, broad ascent will
accompany low level moisture transport, sufficient for a chance of
rain showers across central Missouri. Rain totals will remain light,
generally less than 0.05 inches. The greater impact will be with the
potential for advection fog early Thursday morning. Low level
moisture will advect from the south into the Iowa border and beyond
beginning Wednesday night. Surface dewpoints will begin to increase
as a result and may see areas of patchy to widespread fog as surface
temperatures cool early Thursday morning. Chances of precipitation
will taper off east to west by Thursday evening as the upper wave
lifts into the Great Lakes Region Friday morning.

Temperatures on Friday will continue to rise as warm advection
persists. Could see afternoon highs reach over 60 degrees south
of the Missouri River both Friday and Saturday. Better chances of
widespread precipitation will begin Sunday morning into Monday as
a deep upper level trough matures over the Southern and Central
Plains. While the greatest forcing for activity will remain well
to the south, sufficient moisture transport will wrap around the
attendant surface low, with resulting widespread precipitation
possible across the local area. Thermal profiles will support all
rain throughout the duration of the event. The active pattern
will then continue into the mid-week as another upper level system
approaches the area. Periods of mixed precipitation are possible
with this system, as cold advection returns by the end of the
period.

&&

.Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1117 AM CST WED JAN 18 2017

The fog that has been affecting the terminals should lift by this
afternoon. But low ceilings will likely persist into the evening
before improving, temporarily early tonight. Continued moisture
advection into the area will result in LIFR ceilings and
potentially fog developing again tonight and into tomorrow
morning.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...Dense Fog Advisory until 2 PM CST this afternoon for KSZ057-
     103>105.

MO...Dense Fog Advisory until 2 PM CST this afternoon for MOZ004-005-
     013-014-021-022-028>030-037-043.

&&

$$

Update...CDB
Discussion...Welsh
Aviation...CDB



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