Area Forecast Discussion
Issued by NWS St. Louis, MO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
000
FXUS63 KLSX 300441
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1141 PM CDT SUN MAY 29 2016

.UPDATE...
Issued at 916 PM CDT Sun May 29 2016

Showers and thunderstorms have developed this evening over
northeast Missouri in an area of weak low level moisture
convergence seen on the RAP. Latest objective analysis shows this
area has near 2000 J/kg MUCAPE and 30kts of effective shear.
Expect these storms to gradually weaken later this evening as the
low level ridge move across the area causing the convergence to
weaken. Otherwise, will increase cloud cover with convective debris
moving into the area from the Plains. Lows tonight still look on
track.

Britt

&&

.SHORT TERM...  (Through Late Tonight)
Issued at 248 PM CDT Sun May 29 2016

Scattered diurnal cumulus field has developed across much of the
forecast area this afternoon.  Could not rule out an isolated shower
across southeast MO and southwest IL late this afternoon where there
is a little better low level moisture and instability, but will
leave the forecast dry for now as the probability is very low.  The
cumulus clouds should dissipate early this evening due to the loss
of daytime heating.  There will likely be some high level clouds
tonight.  Discounting the GFS model which has light QPF and chance
pops over northeast MO late tonight.  It does not appear that there
will be enough forcing or moisture to generate any precipitation
late tonight, and will go with the dry solutions of the NAM and
ECMWF models. The surface wind will become light or even calm this
evening with a surface ridge over our area. There should be enough
radiational cooling to allow temperatures to drop into the lower 60s
late tonight/early Monday morning over most of the area with a few
spots in the upper 50s for lows.

GKS

.LONG TERM...  (Monday through Next Sunday)
Issued at 248 PM CDT Sun May 29 2016

Most of the holiday will be dry, but low level flow will bring
moisture back into the region with rain chances increasing as the
day progresses and first in a series of shortwaves slide through
area. So have slight chance/pops mainly for areas along and west
of Mississippi River. Highs will be in the mid to upper 80s
Monday.

Rounds of activity to persist through midweek with best chances of
storms Tuesday night and Wednesday, so have likely pops for most of
forecast area. Have some decent CAPES on Wednesday with frontal
boundary moving through, but it is still too far out to determine if
we will see any severe weather by mid week. Highs through midweek
will be in the in the upper 70s to mid 80s.

Then cold front to exit region bringing in slightly cooler and drier
wx through at least Saturday. However, highs will still be near
normal, in the mid to upper 70s. Could see wet pattern return for
next Sunday, but for now just kept slight chance/low end chance pops
at this time.

Byrd

&&

.AVIATION...  (For the 06z TAFs through 06z Monday Night)
Issued at 1137 PM CDT Sun May 29 2016

Isolated showers and thunderstorms continue to be generated across
northeast Missouri into west central Illinois late this evening. A
few of these may affect KUIN through 08Z. Mainly dry and VFR
weather is expected through the rest of the period at the TAF
period. Only exception may occur at KCOU tomorrow when scattered
showers move into central Missouri during the afternoon. Have
included a VCSH to accommodate this risk.

Specifics for KSTL: Dry and VFR conditions are expected the next
30 hours.

Britt

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$

WFO LSX



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.