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Area forecast discussion 
National Weather Service Omaha/valley NE
620 PM CDT Friday Sep 4 2015

Short term...(tonight through monday)
issued at 256 PM CDT Friday Sep 4 2015

Upper trough along the West Coast and ridge across the Great Lakes
will remain in place overnight. The subtle wave that brought
convection to the area this morning continues to pull away from
the region.

The next wave is across the central rockies...and will likely
develop convection across the northern Front Range tonight.
Meanwhile...a low level jet will redevelop overnight...which could
bring additional isolated convection to northeast Nebraska after
midnight...but the better chances will exist just northeast of
the forecast area across northwest Iowa and southeast South Dakota. If
anything does develop late tonight...it could linger Saturday
morning then go through a diurnal cycle and end before noon.

The remainder of Saturday will be mostly dry...with breezy
southerly winds and hot temperatures once again. With dewpoints still in
the upper 60s/lower 70s...this will create afternoon heat index
values 95 to 100 in some spots. While below advisory criteria...if
you will be outdoors doing any pre Holiday activities...its
something to think about...just be sure to remain well hydrated
with lots of water and take it easy. The next subtle wave could
trigger convection across the High Plains...that could affect
northeast Nebraska late in the afternoon.

Storm chances remain Saturday night north of i80 as the subtle
upper wave moves through...combined with a low level jet. Could be
lingering activity mostly along/north of i80 Sunday morning...that
should exhibit typical diurnal behavior and weaken or diminish by
afternoon.

The front then moves into the forecast area Sunday afternoon/evening.
Wind shear could range 30 to 40 knots in some areas...and instability
could increase to 2000-3000 j/kg. Given that the front will be
impacting the area during peak heating...stronger storms seem
likely...and severe probabilities should warrant at least a
marginal outlook for severe weather along/south of i80 Sunday
afternoon evening when probability of precipitation into the 60/70 percent range. Most
precipitation should push south into Kansas/MO by daybreak Monday...but a few
showers could linger in southeast Nebraska Monday morning.

Precipitation chances increase again by Monday afternoon as the next wave
and moisture return overruns the surface front to our south.

Long term...(monday night through friday)
issued at 256 PM CDT Friday Sep 4 2015

Surface front may lift northward a little Monday night near the
Kansas/NE border. This should trigger additional thunderstorms across
the region...with highest probability of precipitation again at 60/70 percent south of
i80. A few showers could linger early Tuesday before the upper
wave pushes east of the region. It will be cooler next week with
the front south of the region. Highs middle week only reach the middle
to upper 70s...which would be below normal by a few degrees. The
next front moves into the area Wednesday night through Thursday
which will bring the next chance for scattered storms.

&&

Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 620 PM CDT Friday Sep 4 2015

Generally expect VFR conditions through the period. Isolated thunderstorms and rain
will be possible...but chances not high enough to mention at any
of the taf sites for now. Kofk seems to have the best chance...so
did mention a middle level ceiling there later tonight. Low level wind shear will
develop as the low level jet increases...then should end middle to
late morning Saturday.

&&

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

$$

Short term...Dewald
long term...Dewald
aviation...Miller

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