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Area forecast discussion
National Weather Service Omaha/valley NE
620 am CDT sun Jul 21 2019

Short term...(today through Monday night)
issued at 326 am CDT sun Jul 21 2019

Showers and thunderstorms continued to develop through the overnight
hours, to the north of a stationary surface boundary draped from
western Kansas to around Falls City, NE. The main area of concern was
from the far southwest corner of Iowa up to the Platte River in
eastern Nebraska, as an increasing low level jet pulled more moisture into the
region, fueling thunderstorm activity. In fact, pwats were estimated
to be over 2", which would be close to, if not higher than the daily
Max recorded precipitable water for this region. Thankfully, given the lack of
recent rainfall across the area, flash flood guidance was fairly
high across eastern Nebraska and southwest Iowa early this morning.
However, flash flood warnings were issued just to our south in
northwest MO.

Precipitation is forecast to continue through the morning hours
today. Unfortunately, any showers and storms will continue to be
very slow moving, creating the potential for very heavy rainfall
where training occurs. Therefore we will continue to keep a close
eye on any flash flood potential for today. Precipitation coverage
will generally begin to diminish in the afternoon hours, as the
better instability begins to move south of the forecast area, and
support from the low level jet has waned. However, there may be an uptick in
activity, mainly south of I-80, in the mid to late afternoon as an
upper trough pushes in from the west. A few storms today may have
the potential to produce strong winds and hail, in addition to
heavy rainfall. A very small chance for a tornado cannot be ruled
out as well. Overall, rainfall totals are expected to be around 1
to 3 inches through this evening, with locally higher amounts of
up to 5 inches possible, mainly across far southeast Nebraska and
southwest Iowa.

But, there is some good news. We will get a considerable amount of
relief from the heat. High temperatures across most of the County Warning Area
today will be near, if not lower than minimum temperatures that we
saw over the last several days. Highs are forecast to range from
the lower 70s in northeast Nebraska to the lower 80s in far
southeast NE/southwest Iowa. Lows Sunday night will fall well into
the lower 60s and upper 50s across the area with lingering
precipitation finally exiting the County Warning Area shortly after midnight.

Dry weather will continue into Monday as high pressure builds into
the region. Temperatures will remain pleasant, with highs in the
mid to upper 70s and lows dipping into the mid to upper 50s.

Long term...(tuesday through saturday)
issued at 326 am CDT sun Jul 21 2019

High pressure will continue to dominate across the central conus,
keeping US dry through the majority of next week. Temperatures will
gradually climb closer to normal, starting with highs in the upper
70s on Tuesday, and eventually reaching the mid to upper 80s by late
in the week. Models continue to indicate that the ridge will
eventually begin to break down late this week, with shower and
thunderstorm chances returning Thursday night and into the


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 620 am CDT sun Jul 21 2019

A large complex of showers and thunderstorms over portions of
eastern NE as of 6 am is expected to progress east-southeast this
morning with klnk being most directly affected. There, variably
gusty winds will continue for the next few hours along with MVFR
to IFR ceilings and visibilities. Koma will likely remain on the
northeast periphery of the heavier and more persistent
precipitation, as will kofk. Latest model guidance is suggestive
that the showers and storms will shift to the southeast of the taf
sites by mid to late afternoon with prevailing VFR conditions by
late afternoon or early evening.


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