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Area forecast discussion 
National Weather Service Omaha/valley NE
319 am CDT sun Oct 4 2015

Short term...(today through tuesday)
issued at 315 am CDT sun Oct 4 2015

A small chance for showers today...then a gradual warming trend
early next week...are the primary highlights of this forecast.

Upper low was deepening as it settled south along the coast of
California. Strong southwest flow ahead of this feature was tapping
sub tropical moisture from off the western Mexico coast...streaming
through the Southern Plains into eastern Nebraska. One shortwave
noted on water vapor loops was moving out of eastern Colorado this
morning...with 60kt middle level jet punching into Nebraska. Scattered
showers were the result from southwest to central Nebraska...and
isolated returns were noted in northeast Nebraska. Extrapolation of
wave and associated precipitation suggests northeast Nebraska will
have a chance for showers through most of the morning before wave
lifts north of our area this afternoon.

Otherwise we are looking at abundant middle and high level clouds today
across all of eastern Nebraska and western Iowa...tied to
aforementioned moisture plume. This combined with easterly low level
wind component spells only tepid warming this afternoon. Highs only
in the lower 60s will be common...and northeast Nebraska will likely
stay in the upper 50s.

By Monday...western upper low will have bottomed out in Southern
California where it will begin a slow eastward drift into Tuesday.
Ahead of the low...middle level ridging will expand north into the
plains...providing a background environment for warmer temperatures.
At the surface...southerly winds will gradually return as high
pressure ridge slowly moves to the east...and at the 850mb level
southwest flow will promote warming temperatures as well. The main
caveat for strong warming is pesky middle level cloud cover brought on
by fading subtropical moisture plume and persistent warm advection.

But we should still see warmer temperatures than this weekend...with
models consistently putting highs close to 70 Monday and in the middle
70s Tuesday. Overnight lows will also gain a few degrees each
night...with lows likely in the lower 50s Tuesday morning.

Long term...(tuesday night through saturday)
issued at 315 am CDT sun Oct 4 2015

Models seem to be converging on a similar solution for much of
next week as far as middle level flow is concerned. Southwestern
upper low is forecast to drift east into West Texas by Thursday
where it should stall and gradually fill. Stronger northern
stream flow initially across southern Canada into the Great Lakes
will settle south a bit as strong shortwave trough rides across
the northern rockies and drops into the plains by Wednesday night
or Thursday. This scenario is fairly consistent between GFS/European model (ecmwf)
and is not far off from our current forecast.

So we should see one more mild day on Wednesday when southerly flow
and warm advection strengthen ahead of approaching wave. Then
somewhat cooler Pacific air will follow wave Thursday through
Saturday. Precipitation could begin as early as Wednesday afternoon
given warm advection regime...but best chances are forecast
Wednesday night into Thursday when wave and associated front sweep
through our region.


Aviation...(06z tafs for kofk...klnk and koma.)
Issued at 1138 PM CDT Sat Oct 3 2015

VFR conditions expected through the forecast period.


Oax watches/warnings/advisories...


Short term...dergan
long term...dergan

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