Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 242012

Area Forecast Discussion
National Weather Service Saint Louis MO
312 PM CDT TUE MAY 24 2016

.SHORT TERM...  (Through Late Tonight)
Issued at 312 PM CDT Tue May 24 2016

Ongoing storms across srn MO are expected to continue to propagate
ESE this afternoon and shud be E of the CWA by 00z. Some lingering
SHRA with isod TS may continue for a couple of hours. Still expect
development just N of the CWA with a few storms drifting south into
the nrn couple of tiers of counties before dissipating. Have kept
PoPs at low chance or less due to uncertainty in timing and

Focus will be on MCS development across NEB/KS. While it appears the
bulk of the activity will remain N of the CWA. However, as this
system breaks down the upper level ridge, it seems that activity
will drop into wrn portions of the CWA late tonight and likely
persist into Wed morning.  More on that below.

Otherwise, some guidance suggests that additional storms may develop
within the broad WAA further S across the srn half of the CWA. Have
kept PoPs rather generic due to uncertainty in how the event tonight
will unfold.


.LONG TERM...  (Wednesday through Next Tuesday)
Issued at 312 PM CDT Tue May 24 2016

Several rounds of convection can be expected for the remainder of
the work week and into the weekend with southwest flow shortwaves
moving through the region coupled with persistent warm, moist and
unstable southerly low level flow.  Convection is expected to sweep
northeastward through our forecast area Wednesday morning into the
early afternoon hours ahead of a shortwave and on the nose of a
south-southwesterly low level jet.  Much of the convection should
shift east-northeast of the forecast area by late afternoon,
although could not rule out a few storms redeveloping during the
late afternoon/early evening along any left over outflow boundaries
from the morning storms.  May be a lull in convective activity
during the late evening and overnight hours Wednesday night. Prefer
the drier solution of the NAM model during this time period over the
GFS.  Looks like mainly just scattered diurnal showers/storms
Thursday afternoon and early evening.  With a little more solar
insolation expected and less morning convection, highs should be
warmer on Thursday and easily around 10 degrees above normal for
late May.  More widespread convection is expected on Friday and
Friday night as an upper level trough approaches our area from the
Plains.  Highs on Friday will be cooler due to the increased cloud
cover and greater coverage of showers/storms.  Fairly widespread
convection will continue on Saturday as the upper level trough
becomes more negatively tilted and moves northeastward through our
area.  Should see less active weather by late Saturday night and
continuing for the remainder of the weekend after the upper level
trough shifts northeast of the region.  For the start of the next
work week the warm and humid weather pattern will continue with
mainly scattered afternoon and early evening showers and storms with
mainly weak southwesterly upper level flow and weak surface winds
due to a weak surface pressure pattern.



.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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