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

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FXUS63 KEAX 180431

1131 PM CDT Fri Apr 17 2015

Issued at 718 PM CDT FRI APR 17 2015

Updated the forecast this evening to up the POPs across northern
Kansas City and points north into the northwest corner of Missouri.
Looks like a bit of isentroipic assent associated with a spoke of
vorticity rotating north through eastern Kansas and western Missouri
has sparked some showers and/or isolated thunderstorms to the north
of Kansas City. Can not rule out more widespread development of
storms later this evening, but lack of any current radar trends or
cloud development on satellite seems to indicate that it will likely
be after midnight before more widespread activity develops to our
southwest and sweeps through during in the early morning hours of


.SHORT TERM...(This Evening through Sunday Night)
Issued at 337 PM CDT FRI APR 17 2015

Overview: Closed upper low currently over the Four Corners region
will evolve into an open wave during the weekend as an upper trough
amplifies over the northern CONUS. This upper low will be
responsible for an active period of weather across the region
tonight into Sunday.

Tonight: In the short-term, a band of showers and embedded
thunderstorms rapidly dissipated along the KS/MO border, and has
temporarily stabilized much of the area seen as a decrease in the
low-level cumulus field. A lull in precipitation is expected for
much this evening, with only slight chances for isolated convection to
develop over the western CWA. Additional convection is expected to
develop over the Central Plains later this afternoon/evening. This
activity will eventually shift eastward into portions of the forecast
area overnight. With marginal wind fields and instability expected to
support much in the way of storm organization, severe weather is not
expected tonight.

Saturday through Saturday night: Widespread convection is expected
to be ongoing Saturday morning, although the exact eastward extent
remains uncertain, primarily tied to position of upper low and
convective evolution/outflow. As the day progresses, may see a break
in the precipitation over portions of the area, before another round
of convection develops. The amount of instability by afternoon will
be tied to how much, if any, clearing can occur from morning
convection. Currently, instability is expected to be marginal, with
MUCAPE around 1000 J/KG. Wind fields will gradually increase as the
day progresses with the upper low making slow eastward progress. The
western half of the CWA is likely to see the most favorable
combination of strengthening wind fields and marginal instability,
and there is a slight chance a few storms during the afternoon/early
evening may be strong to briefly severe. Again, much will depend on
the eventual behavior/evolution of overnight/AM convection.
Thunderstorms are expected to remain possible during the
evening/overnight periods on Saturday.

Sunday through Sunday night: Another lull in convection is possible
early Sunday, and again will monitor the degree of any potential
clearing leading to increased instability. The open wave will
approach/move across the region Sunday into Sunday night. Models
have been persistent in developing a primary surface low over SE MO
by Sunday morning with another shortwave trough swinging around the
opening wave. This results in strongly veered surface winds over the
area, helping to decrease low-level shear over the forecast area. A
cold front will move through the CWA Sunday afternoon, likely
spawning additional thunderstorms along the boundary. Depending on
the amount of destabilization, a few strong to isolated severe
storms will be possible with this activity, with a marginal hail and
wind threat. Precipitation will finally come to an end from west to
east around midnight Monday.

While the overall severe weather threat remains low for our area
through the weekend, the potential for localized flooding will
increase over the coming days in areas that receive consecutive
rounds of moderate to heavy rainfall. Precipitable water values will
remain well above seasonal levels as the upper wave slowly moves
through the area. Will closely monitor convective trends overnight
and the need for a flood watch for the potential of several rounds of

.LONG TERM...(Monday through Friday)
Issued at 337 PM CDT FRI APR 17 2015

A semi active period remains for the mid range and extended period,
as marginal residual moisture remains in the area. A broad trough to
the east/northeast will keep the majority of the area within a large
scale northwest flow regime aloft, which will preclude and real
focus for rain chances mid week, but mid range models do indicate
the chance for some mid level ascent to round the trough. Expect
only a batch of very light rain on Wednesday, with only very minor
accumulations. For the late part of the week, perhaps a more focused
batch of precipitation will be in store for the area as southerly
surface flow advects some some modest moisture back into the area.
Once the weak mid level ridge moves through the area southwest flow
aloft is progged to move in, which could bring more widespread
convection for the late part of the week, into next week. Much too
early to nail down specifics of timing and/or amounts, but with some
decent moisture moving in, along with a look at some mid level
ascent associated with a trough out west, it appears that rain is
well within reason for late next week.


.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1129 PM CDT FRI APR 17 2015

VFR conditions will likely prevail at the terminals through the rest
of the overnight hours as the forecast for storms looks to have
slowed. Storms still look likely in the morning, but now it appears
that it will be after sunrise before anything sweeps across our
terminals. Thunderstorms are forecast to redevelop in the late
afternoon hours. Otherwise, easterly surface wind overnight will veer
to the south through the morning hours, with speeds remaining less
then 10 knots.




LONG TERM...Leighton
AVIATION...Cutter is the U.S. government's official web portal to all federal, state and local government web resources and services.