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fxus63 koax 181108 
afdoax

Area forecast discussion
National Weather Service Omaha/valley NE
608 am CDT Wed Sep 18 2019

Short term...(today through friday)
issued at 343 am CDT Wed Sep 18 2019

Primary concern is heavy rain potential into the weekend and the
continued rising levels on the Missouri River.

The region remains in moist southwesterly flow aloft between
amplified ridging to our east and broad troughing across the western
Continental U.S.. a surface cold front extends northeastward from northwestern
Kansas into north central Nebraska and into southeast Kansas. Broad
isentropic lift over the area has produced scattered showers across
northern portions of the County Warning Area overnight ahead of this cold front.
As our nocturnal low-level jet begins to diminish after day-break,
showers and thunderstorms are expected to diminish as well
leaving much of the late morning/early afternoon dry. Meanwhile,
the weak surface front will nearly stall and extend from southwest
to northeast across the forecast area by mid-afternoon.
Thunderstorms are forecast to develop near the boundary by late
afternoon/early evening as a series of embedded mid-level
shortwaves move northeast across the area. Training convection is
possible as low /mid-level flow parallels the boundary. Pwat's are
forecast around 200% of normal for this time of the year with
pw's around 1.5-2" at times. Convection will likely increase
through the night as a veering nocturnal low-level jet increases.
Rainfall amounts of near 0.75-1.50" is possible in the heavy
rainfall axis with locally heavier amounts possible. A few
scattered showers could linger through the day Thursday,
especially in our eastern counties, but much of the day should
remain mostly dry.

Long term...(friday night through tuesday)
issued at 343 am CDT Wed Sep 18 2019

The next chance for rain will come Friday night into Saturday as a
surface front slides south across the area ahead of a large
mid/upper level moving northeast across the the High Plains. Ahead
of this trough will reside a moisture-rich environment with
pwat's still about 200% of normal. Heavy rain is certainly a
possibility once again.

An upper-level shortwave trough will move east across the Central
Plains later in the weekend which will keep showers and
thunderstorms in the forecast. Surface high pressure begins to build
over the area for early next week bringing drier and cooler weather
to the region.

&&

Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 604 am CDT Wed Sep 18 2019

A few spotty showers and storms will be possible this morning,
potentially affecting koma and klnk. There should be a break in
precipitation this afternoon, before rain chances increase
overnight. Generally VFR conditions are expected, however MVFR or
lower will be possible in and around thunderstorms.

&&

Hydrology...
issued at 343 am CDT Wed Sep 18 2019

Minor to moderate flooding will continue along the Missouri River
from Decatur south to Rulo with flood warnings in effect. Rivers
are forecast to crest Wednesday through Saturday due to the runoff
from heavy to record rainfall over South Dakota. Additional
rainfall over the next few days could impact these forecasts and
potentially delay the crests. The Current River forecasts take
into account the rainfall forecast only for the next 24-hours.

&&

Oax watches/warnings/advisories...
NE...none.
Iowa...none.
&&

$$

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