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Area forecast discussion...updated aviation 
National Weather Service St Louis MO
1233 PM CDT Thu may 28 2015

Short term: (through late this afternoon)
issued at 323 am CDT Thu may 28 2015

Weak frontal boundary that moved south through forecast area
yesterday has stalled out just south of region. It will begin to
lift back north through forecast area today, with some scattered
showers and thunderstorms possible mainly during the afternoon
hours. In the meantime, storm complex over central Kansas early
this morning will continue to track to the east, reaching central
MO by midday. At this point, it will be in the weakening stages.
Otherwise, it will be warm and a bit muggy with highs in the low
to mid 80s and dewpts in the 60s.

Byrd

Long term: (tonight through wednesday)
issued at 323 am CDT Thu may 28 2015

By tonight, first in a series of more vigorous shortwaves will begin
to slide through forecast area. Showers and thunderstorms will be on
the increase with best chances still expected Friday through
Saturday. As for severe weather potential, it will be with main cold
front Friday afternoon and night, and again on Saturday. It
continues to hinge on how much instability can be attained in the
warm sector ahead of boundary.

Temperatures will remain on the warm side through Friday, with highs
in the 80s. Then colder air to filter in as front moves through. By
Sunday, precipitation to taper off and will see highs only in the
60s.

Beyond that, upper low becomes cut off and lingers over Arkansas
through rest of forecast period. Could see diurnally driven showers
and thunderstorms, mainly for southern portions of forecast area,
from Monday through Wednesday, so have slight chance pops during the
daytime hours. Highs to moderate through the period, warming back
into the 80s by Wednesday.

Byrd

&&

Aviation: (for the 18z tafs through 18z Friday afternoon)
issued at 1220 PM CDT Thu may 28 2015

An east-west oriented warm front was located just south of Interstate
70 extending from southern Kansas across southern MO into southern Illinois
at midday. A warm and unstable air mass was located along and
south of this front. The front will slowly lift northward this
afternoon allowing the northward spread of the warm and unstable
conditions and fueling scattered showers and thunderstorms. Already
an organized cluster of storms is located south of kcou and thus
have a tempo group this afternoon, while the coverage and direct
impacts are less certain for the St. Louis region terminals and
opted for thunderstorms in the vicinity. Will monitor closely thru the afternoon and amend as
needed if direct terminal impacts are evident. Much of this
activity should diminish at sunset however another area of showers
and thunderstorms originating in western MO this afternoon has
potential to impact kcou early this evening and possibly KUIN.
Otherwise a mix of high-end MVFR and low-end VFR cigs are expected
this afternoon with potential for MVFR cigs again on Friday
morning.

Specifics for kstl:

A warm front will move north of the terminal this afternoon allowing
for the northward spread of warm and unstable conditions. Scattered
showers and thunderstorms are possible within the St. Louis Metro
area between 19-23z however direct terminal impacts are uncertain
given the scattered coverage of storms and have opted at this time
for thunderstorms in the vicinity. Will monitor closely thru the afternoon and amend as needed
if direct terminal impacts are evident. Much of this activity
should diminish at sunset. Otherwise a mix of high-end MVFR and
low-end VFR cigs are expected this afternoon with potential for
the same flight conditions again on Friday morning.

Glass

&&

Lsx watches/warnings/advisories:
MO...none.
Illinois...none.
&&

$$

Weather forecast office lsx

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