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Area forecast discussion 
National Weather Service Des Moines Iowa
331 am CDT Sat Aug 30 2014

Synopsis...
issued at 320 am CDT Sat Aug 30 2014

Weak cold front will exit the state today with weak ridge passing
over Iowa this evening. Next frontal system will move into the High
Plains late Sunday night and pass through Iowa Monday. High pressure
will then dominate the weather patter through middle week.

&&

Short term /today/...

Issued at 320 am CDT Sat Aug 30 2014
low pressure system will continue to pull eastward through the early
morning hours...with lingering lighter precipitation across the
north and the east in the morning hours. System will finally push
east...bringing a much needed dry day for central Iowa today. Given
amount of low level moisture have kept fog mention through the
morning hours...with the potential for dense fog in the west where
winds will be lighter in the early morning hours. However...believe
clouds will help limit fog...and have left dense fog mention out
at this time...though will continue to monitor. Also given amount of
moisture have kept clouds a bit longer into the afternoon...though
as system pushes east middle level dry air will work in and will see
clearing. Warm air advection will begin to increase in the south and west in the
late afternoon...and have therefore kept highs near going.



Long term /tonight through Friday/...
issued at 320 am CDT Sat Aug 30 2014

Decent Theta-E advection sets in tonight and do have some concern
over that for late tonight as low level jet begins to pick up. Will need to
be watched for the later forecasts for the possibility of some
elevated convection late tonight. The main weather story for this
package will be late Sun afternoon and Sun night. With the
passage of the cold front and decent dynamics in place...strong
to severe thunderstorms will be possible expecially over the
northwest half of the state. Feel the window will be somewhat
narrow with the very moist airmass in place...precipitable waters approaching 2
inches...and the k index exceeding 40.

Following the cold front...mild airmass will be in place with
temperatures above normal through a good pattern of the week. Rain chances
will decrease for the middle part of the week with the next frontal
system expected to bring thunderstorms about Friday or Sat into the
weekend.

&&

Aviation...30/06z
issued at 1214 am CDT Sat Aug 30 2014

Ceilings and visibility trends will be the primary concern through Sat
morning as upper low and associated scattered convection passes
through Iowa. Conditions are quite variable across the state at 05z
ranging from LIFR to VFR. Although confidence in details is
low...generally kept scattered showers/isolated thunderstorms going
through 09z or so as system exits. Surface flow will be weak
behind surface trough passing through central Iowa at the moment and
coincident with plenty of lingering low level moisture so lowered
ceilings/visibilities before typical diurnal rebound into VFR conditions
later Sat. Category confidence low so started with IFR/MVFR
although either side of that may occur.



&&

Dmx watches/warnings/advisories...
none.
&&

$$

Synopsis...MS Aug 14
short term...awb
long term...MS Aug 14
aviation...small

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