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fxus63 kgid 181120 

Area forecast discussion
National Weather Service Hastings NE
620 am CDT Wed Sep 18 2019

Short term...(today and tonight)
issued at 429 am CDT Wed Sep 18 2019

Southwest flow aloft is occurring as a compact, but vigorous
shortwave trough heads to the northeast across the northern
plains. The associated cold front is beginning to make some
headway into our cwa, but is in the process of stalling, and may
stall a little earlier than previous forecasts. This has prompted
ME to expand some slight chances over much of the County Warning Area this
afternoon and into the night. Most numerical models are rather
meager with pops and qpf, but the GFS (a clear outlier), paints US
with quite a bit higher chances of precip. With lack of much
forcing, and only enhanced cape to work with, i'm going to side
with lower pops here. However, with the stalled front draped
across US along with a decent amount of instability, I felt
compelled to have something in there. That being said, I can't
rule out a strong storm seeing that cape should easily surpass
2000 j/kg this afternoon, and MUCAPE will as well tonight as well.
The hrrr and the namnest, among others, are advertising a linear
mesoscale convective system developing late tonight after midnight, with these solutions
indicating that we could be scraped by this as the far western
edge of the potential mesoscale convective system may make it just within our County Warning Area. With
such small scale features, I don't want to get too cute with pops
for now, and put a bit of an increase in pop in our far east, as
it will likely be almost all east of US.

Long term...(thursday through tuesday)
issued at 429 am CDT Wed Sep 18 2019

The stalled front looks like it eventually washes out as flow
becomes more south. The remnants of the surface front may be
enough to spark more storms on Thursday. The pressure gradient
looks reasonably strong on Friday to bump up wind speeds to just
under what we experienced on Monday.

It appears our next decent chance of rain looks like Friday night
as a cold front is forecast to sweep through and finally
introduce truly drier and cooler air, associated with a much
stronger and deeper trough than the one that is tracking across
the northern plains today.

Although specifics are difficult as numerical model forecasts
diverge, it does appear we will get truly cooler and drier air, as
highs eventually fall into the 70s toward the end of the long term
forecast. We could have another shot at some rain, especially late
Saturday night.

We will continue to be in an active pattern, but we are
consistently forecasting a completely dry period for Sunday night
into Monday.


Aviation...(for the 12z kgri/kear tafs through 12z thursday)
issued at 559 am CDT Wed Sep 18 2019

Low level wind shear concerns have ended and wind speeds have sharply decreased
as the expected slow-moving cold front is in the vicinity. Wind
direction will be a bit tricky as the front is relatively week,
and as the boundary stalls, there will not be that strong of a
north component. Will hang on to some thunderstorms in the vicinity late this afternoon and
into the evening as some elevated Post-frontal convection may
occur, but not very likely. After 06z Thursday, models indicate
the potential for an mesoscale convective system to head south across eastern Nebraska,
but for now, it appears that this should remain far enough east of
both terminals to keep this out of the forecast. Some models are
indicating getting close to low level wind shear potential in the 08 to 10z
Thursday time frame, but this appears weak enough to keep out of
the forecast at this time.


Gid watches/warnings/advisories...


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