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

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FXUS63 KEAX 012128

428 PM CDT Wed Apr 1 2015

Issued at 427 PM CDT WED APR 1 2015

Tonight - Thursday:

In the very near term an area of convection tied to a pesky MCV over
southwestern MO is expected to track northeast and graze the far
southeast CWA through early evening. Have increased PoPs over this
region to account for this.

Attention then turns back to the west and northwest and focuses on
two areas...the NE/SD cold front and an area of accas from western
KS into the TX Panhandle. Per latest RAP analysis and visible
satellite imagery the airmass remains capped within the cold fronts
baroclinic zone. Low-level moisture taking its time to arrive.
Latest NAM/RAP suggest CIN may not be eroded till closer to 00Z.
Still expect a line of convection to form this evening with the
front sliding east-southeast overnight. This activity expected to
reach far northwest MO towards midnight and then continue across
northern MO. Second area being watched is the KS accas and 12z NAM
defined a h7 shortwave/vorticity max that will move out of CO this
evening. Last several runs of the convective allowing HRRR generates
an expanding area of elevated convection which tracks east
overnight, crossing the KS/MO border after midnight. 18z NAM qpf
hints at this convection but delays the arrival till after 09z. Will
side towards the HRRR for now.

While the severe threat will be greatly muted due to its arrival
time and minimal instability some generous qpf is possible over our
northern and western counties. The latter due to the southerly low
level jet veering overnight and paralleling the cold front which
could result in some post frontal training for several hours.

Convection likely to exit the CWA quickly from west to east
Thursday morning. However, model consensus indicates the front will
stall just south of the CWA, close enough that low chance afternoon
PoPs necessary across the far southern counties to account for
potential late afternoon redevelopment.

Thursday night - Friday night:

The aforementioned stalled front will likely remain just south of
the CWA during this period. However, post frontal stratiform or weak
elevated convective rains are likely north of the boundary Thursday
night into Friday morning. An upper level trough is progged to shift
eastward within a pseudo westerly flow with pieces of energy
ejecting ahead of it through the Central Plains. This should allow
for some isentropically induced rain to form and affect most of the
CWA. The rain chances will end by Friday afternoon with the passage
of the trough axis. Temperatures will be on the cool side and hover
in the 50s all day.

Clearing skies, light winds and cool high pressure will probably
send Sat morning lows to freezing or below.....with a good chance
for a frost.

Saturday - Sunday:

Should be a rather benign weekend with weak ridging aloft
translating eastward and surface pressure falls across the plains
generating a southerly breeze. Should be a very pleasant weekend
with above average temperatures.

Sunday night - Wednesday:

Looks like an unsettled pattern. Southwesterly flow sets up with the
passage of the upper ridge allowing for increasing moist warm air
advection. Considerable model uncertainty on PoPs and timing of the
next cold front. GFS is much faster and brings a cold front through
Monday night in response to a fast moving shortwave coming out of
the desert southwest on Monday whereas the 12z ECMWF shows no sign
of this wave...maybe A poor reflection by 12z Tuesday. In any event,
there is the potential for a couple pieces of weak energy to be
embedded within the southwesterly flow and give us a chance for some
convection. Temperatures are likely to remain above average for the
first part of the week.


.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1236 PM CDT WED APR 1 2015

Scattered convection over southwest MO will move into parts of west
central and much of central MO after 19z and last into the early
evening hours. Generally VFR ceilings except briefly MVFR with the
strong storms.

Gusty southerly winds into early evening. Winds veer to the northwest
with passage of cold front after midnight.

Otherwise, will delay arrival of line of convection associated with
approaching cold front by a few more hours with activity crossing
into far northwest MO after midnight. Strongest storms/heaviest
precipitation should be across northern MO with activity becoming
more scattered and less intense to the southwest. Line should weaken
as it shifts southeast into west central and central MO towards
sunrise. MVFR ceilings most likely with the convection, probably
several hours of IFR over northern MO. Precipitation will end from
west to east by late morning with ceilings improving to VFR by mid




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