197
FXUS63 KEAX 161732
AFDEAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1232 PM CDT Wed Oct 16 2013
.SHORT TERM...(Today through Friday)
Issued at 329 AM CDT WED OCT 16 2013
08Z surface analysis shows that cyclonic flow, associated with a
filling trough over the western Great Lakes, extended as far south
and west as NE KS/nrn MO. Meanwhile, a surface high pressure ridge
was centered over SE CO with its axis stretched across srn MO into
the mid Mississippi Valley. A narrow area of clearing wedged through
central MO, anchored between widespread stratus to the north and
persistent convective mid level cloud cover to the south associated
with the upper jet.
For today, short term model guidance suggests that the cyclonic
influence will quickly lose its grip over NE KS/nrn MO by late
morning. It's not surprising that even at a favorable time of night,
cloud cover has actually been eroding as it tries to reach a Kansas
City-Moberly line. This may be roughly the southern limit of broken-
overcast through this morning, with temperatures some 5-7 degrees
colder in the clearing zone across west central MO/ern KS. On the
heels of this system, a secondary trough will dig into Iowa/Nebraska
this afternoon, spreading extensive mid cloud cover back into the
area. This will make temps tricky for this afternoon, with sunshine being
highly variant across the CWA. All things considered, diurnal heating
may end up evening out and saw no reason to vary from a 57-60 range.
Clouds will continue to spread in from the southwest early this
evening ahead of the approaching trough. 00Z models show that this
secondary trough closes off and quickly goes from positive to neutral
to negative tilt. Pre-existing mid level baroclinity coupled with a
cyclonically curved jet stream suggest that differential PVA ahead of
this trough may have enough support for a band of rain to develop
this evening despite the lack of a larger moisture source. Certainly
a light QPF event, but will retain 20-30% POPs along and SE of a
Kansas City to Kirksville line this evening and tonight.
After a break Thursday afternoon and some milder readings,
persistent large scale troughing will deliver another slug of cloud
cover Friday, and possibly some light rain late Friday afternoon
into Friday night.
.LONG TERM...(Saturday through Tuesday)
Issued at 329 AM CDT WED OCT 16 2013
Little change in the medium range portions of the forecast, as
eastern 2/3rds of the CONUS will be dominated by a large upper
trough. Shortwave energy which moves through the region Friday will
bring slightly cooler air in for the weekend, with temperatures
either side of 60 both days or about 5-10 degrees below normal.
Heading into next week, several waves of energy will drop southward
out of Canada, rotating around the upper trough. Each of these waves
will bring a limited chance for light rain, with one of these waves
timed in around Monday.
For those concerned with the end of the growing season and potential
arrival of frost/freeze conditions, begin keeping an eye on the
middle of next week for a much stronger shot of cold air poised to
plunge into the CONUS. GFS/ECMWF both advertise a potent cold front
moving through the area Tuesday night, with 850mb temperatures
dropping well below zero over much of the central Wednesday through
Friday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1232 PM CDT WED OCT 16 2013
MVFR stratus will continue to slowly erode across the area, and could
mix enough to lift ceilings to above 3 kft even in areas of far
northern and northeast Missouri that may not see breaks in the
clouds this afternoon. Stratus should exit the region by this evening
but will be replaced by a midlevel cloud deck lifting in from the
southwest tonight. Cloud bases should stay above 8 to 10 kft with
this second surge of cloud cover. Northwest winds will gradually
turn to the west this evening, then becoming light and variable
overnight.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...Bookbinder
LONG TERM...Dux
AVIATION...Laflin