Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 241755

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1255 PM CDT TUE MAY 24 2016

Issued at 956 AM CDT Tue May 24 2016

A number of questions still remain, but given latest radar trends
and current environment, believe ongoing convection will gradually
dissipate as it moves ewd as it encounters unfavorable
environment. How far E these storms will propagate before
dissipating, is uncertain. This will be complicated as both
clearing occurs ahead of the ern cluster of storms and with
clearing behind as the outflow from earlier convection propagates
ewd. This outflow is still expected to initiate convection later
today. With the cluster developing across swrn MO, as well as more
widespread convection developing ahead of it across srn MO, may
need to update PoPs again across srn portions of the CWA to
continue these TSRA ewd across the area. Will continue to monitor
and update as needed.


.SHORT TERM... (Through Tonight)
Issued at 227 AM CDT Tue May 24 2016

MCV located across the eastern Ozarks/southeast Missouri has
been slowly marching east overnight and has had a few showers
associated with it. A handful of the convection allowing models
develop some thunderstorm activity with this feature toward sunrise,
while others do not. Of more importance is the convective complex
developing across north central Kansas at this time. Model guidance
is struggling on the details of how this feature evolves/moves
today. Some models advance it south-southeast into southwest
Missouri this morning essentially keeping the CWA dry, while others
march it east along I-70 into east central Missouri by this
afternoon/evening. Given the elevated nature of the convection and
its ties to the low level jet and location of the best instability
across the central/southern Plains I would suspect that this
activity will initially propagate toward southwest Missouri this
morning, but the residual outflow will help to initiate additional
convection further northeast along and south of I-70 this afternoon
as the atmosphere diurnally destabilizes. Some of these storms could
become strong/severe with large hail and damaging wind gusts being
the primary threats.

The diurnal activity should weaken with sunset and move east of
the area during the early evening. Next round of thunderstorms
should develop overnight as the low level jet intensifies and
another shortwave ripples across the region. This activity will be
centered further northwest though (thinking along and north of
I-70 in Missouri). These storms will have the potential of
producing large hail.


.LONG TERM... (Wednesday through Monday)
Issued at 227 AM CDT Tue May 24 2016

Convective trends become harder to pin down as much of it will
again depend on what occurs each night. At this point it appears
that the morning convection on Wednesday will move east and the
atmosphere may destablize enough for another round of
thunderstorms during the afternoon/evening, though more
isolated/scattered due to the weak ridging in the wake of the
overnight/early morning shortwave.

Pattern remains active through the weekend and into next week, with
chances of thunderstorms each day and temperatures remaining warm
with highs in the 80s each day.



.AVIATION...  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1238 PM CDT Tue May 24 2016

For KCOU/KUIN...Outflow, evident in sat image, may be a focus for
additional TSRA development this afternoon. If these storms
develop, believe UIN will have best chances of impact given COU
continues under convective debris. Expect MCS to develop tonight
west of the area and move into the region late tonight into Wed
morning. Confidence in timing remains low, but decided to back off
onset due to latest guidance. Otherwise, expect VFR conditions
with generally sly winds.

Specifics for KSTL/KSUS/KCPS: Ongoing SHRA with isod TS over ern
MO is expected to continue to dissipate and slowly sink swd this
afternoon as it moves ewd. Will leave mention of VCTS to account
for this area of precip, but also for convection mentioned above
to possibly propagate swd into the region. Expect area of TSRA
mentioned above to possibly impact terminals mid to late Wed
morning as a s/w moves ewd thru the area. Exactly where any
nocturnal convection tracks is uncertain attm, and will leave only
mention of VCTS for now. Otherwise, expect VFR conditions outside
of any convection with generally sly winds.





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