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Area forecast discussion 
National Weather Service St Louis MO
345 am CDT Sat Aug 2 2014

Short term: (through late this afternoon)
issued at 345 am CDT Sat Aug 2 2014

Areas of fog, some of it dense, will persist until sunrise. Expect
the fog to dissipate pretty quickly thereafter. Looks like the rest
of the day should be pretty uneventful. Northwest flow aloft will
persist, but as opposed to friday's shortwave trof passing
overhead, today a shortwave ridge will be building across the area.
Temperatures should be continuing to moderate today with highs
generally a couple of degrees above friday's.


Long term: (tonight through friday)
issued at 345 am CDT Sat Aug 2 2014

A longwave upper trough will persist over eastern North America thru
Tuesday. The models have had depictions of upper level disturbances
rolling into our area in the resultant northwest flow but have had varying
strengths and timing and never were very consistent. Well that
really hasn't changed with this set of model runs, with most saying
another disturbance will drop down late Sunday. The moisture looks
decent with the disturbance attempting to supply the lift, but
soundings also show a capping inversion around 600mb. Sided with a
dry forecast but went into the 10-14% pop range however. Heading
into early next week starting with Monday, a frontal boundary will
move into the northern part of MO and central Illinois and provide added
focus for rain showers and thunderstorms and rain development. Have added pops back into
Monday and Monday night, mainly around the Quincy and Hannibal areas
with the mid level cap also weakening enough to provide for deep
convection where a focus can be found.

For mid and late next week, the models have shifted a bit in their
depictions. Gone is the strong storm system that gets stalled in
the upper Midwest, with a more disjointed and split flow in its
place with placement of any upper level disturbances too low
confidence to base a forecast off of...with ridging to attempt to
build in for next weekend. All in all, a rather low confidence
forecast on many fronts. The one thing of some consistency going in
this period is presence of a frontal boundary for Tuesday thru
Thursday and have largely maintained the at or above climo pops
(20%+) as a result.

Max temps should be at or slightly above normal thru Wednesday, with
a bit of a drop for a day on Thursday, with a return to above normal
for Friday and into next weekend.



Aviation: (for the 06z tafs through 06z Saturday night)
issued at 1147 PM CDT Fri Aug 1 2014

Areas of fog are continuing to develop late this evening with ksus
just falling below 2sm. Now expect all of the taf sites to have
fog tonight, with the lowest visibilities most likely at ksus and
kcps. Visibilities may vary though...going from MVFR to LIFR
depending on the Airport with the lowest visibilities being
between 10-12z. Fog should lift by 13z as it has the past several
mornings with scattered clouds developing between 16-18z. Expect
dry conditions with light winds through the period.

Specifics for kstl: still expect some MVFR fog to develop at the
terminal between 10-13z because of the higher moisture in the
atmosphere tonight. Otherwise expect a dry conditions with light
winds the next 30 hours.



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