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Area forecast discussion 
National Weather Service Omaha/valley NE
330 PM CDT Friday Jul 3 2015

Short term...(tonight through monday)
issued at 325 PM CDT Friday Jul 3 2015

The primary forecast concerns are in regards to thunderstorm potential from
late Saturday night into Monday.

Our area remains in northwest middle level flow. A few shortwaves were
embedded in this flow. The strongest wave was moving over southwest
Canada at 12z this morning. 12 hour height falls were about 120
meters in northern British Columbia/northern Alberta and this was
associated with a 100 plus knot jet maximum at 300 mb. Surface analysis
early this afternoon showed weak high pressure over the area.

Tonight and Saturday...that area of high pressure at the surface
will move off to the east with southerly flow increasing...
especially Saturday. There may be some patchy fog late tonight...
but right now did not feel it was needed in the grids or public
forecast. The middle levels will be warming during this period. 700
mb temperatures locally this morning were 5-6 degrees c but will
reach 8-10 degrees c by Saturday evening. Look for lows tonight
in the upper 50s/lower 60s and highs Saturday mainly 82 to 86.

Forcing and moisture amount are not impressive but may be enough
for isolated showers or thunderstorms Saturday night...mainly after
midnight. These could linger into Sunday morning. The rest of
Sunday looks warm and dry...with middle levels continuing to warm
which will tend to strengthen the cap. A frontal system will be
moving toward the area for Sunday night...with increasing thunderstorm
chances. Timing of storms is also problematic...and some severe
weather appears possible. This threat...especially Sunday evening
across northeast Nebraska...is conditional if the cap breaks.
Rain chances should be highest after midnight Sunday night.
Precipitable water values will increase to around two inches...so
locally heavy rain will be possible.

The front will continue to push southeast on Monday...so kept probability of precipitation
mostly in the 40-60 percent range.

Long term...(monday night through friday)
issued at 325 PM CDT Friday Jul 3 2015

This period starts out on the cool side with weak northwest middle
level flow. That flow turns to the west...and then southwest late
in the week as a trough moves into the western United States.

High pressure building in at the surface early in the week will
bring mainly dry weather by Tuesday. As that high pressure moves
away...precipitation chances will increase into the 20-30 percent range.

Highs of 75 to 80 Tuesday should warm to the middle 80s by Thursday/
Friday. Lows in the upper 50s/lower 60s Tuesday should moderate
into the middle and upper 60s by late in the work week.

&&

Aviation...(18z tafs for kofk...klnk and koma)
issued at 1225 PM CDT Friday Jul 3 2015

MVFR ceilings are lifting at kofk and are close at klnk. Will leave
MVFR mention in for a couple of hours at kofk...then VFR ceilings at
both kofk and klnk fl035-050 this afternoon. Some patchy fog
possible Saturday morning.

&&

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

$$

Short term...Miller
long term...Miller
aviation...zapotocny

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