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Area forecast discussion 
National Weather Service Amarillo Texas
620 am CDT sun may 24 2015

ceilings slowly improving at the terminals to begin the 12z taf
issuance. Kama has managed to improve to VFR but a MVFR/IFR stratus
deck surrounds it on all sides. Would not be surprised to see a brief
period of time where this stratus deck moves back over kama. By 15z
all terminals should be VFR and remain VFR through the remainder of
this taf issuance. Surface winds at kama and kdht will veer towards
the southwest through the morning hours while kguy back to a easterly
direction as a Lee side low over northeastern New Mexico deepens.
This low will lift throughout the day and allow kguy to veer towards
the southwest by the end of this taf issuance.


Previous discussion... /issued 433 am CDT sun may 24 2015/

intermittent thunderstorm chances through the period pose the main
forecast challenge.

The upper low responsible for the latest stretch of active weather
was centered over northwest Colorado early this morning. Aside from a
lingering shower across the eastern OK Panhandle...the remainder of
the precipitation has shifted east of the area. A moist southeasterly
low-level upslope flow remains in place...resulting in a low stratus
deck and some patchy fog.

A shortwave trough rounding the parent upper low is currently located
over the panhandles...and will lift northeast into the Central
Plains today. Lift ahead of this shortwave...along with weak low-
level warm air advection/isentropic lift along the axis of a veering low-level jet
could initiate a few isolated showers or weak thunderstorms across
the eastern panhandles this morning. The dryline is expected to mix
into the central panhandles this afternoon as surface low pressure
deepens over far southeast Colorado/northeast nm/the western OK Panhandle.
However...strongly suspect the dryline will lag farther west than
prognosticated by models given all of the recent rain and very wet
grounds...and will likely end up being more diffuse than shown in
models for these same reasons. With this in mind...have kept low probability of precipitation
in this afternoon a little farther west than supported by model
guidance. Isolated to perhaps widely scattered storms could develop
this afternoon along and east of the dryline...although forcing will
be fairly weak. In fact...the area may be experiencing weak
subsidence this afternoon in wake of the aforementioned shortwave
trough lifting into the Central Plains. This will limit storm
chances/coverage. A little stronger forcing will exist across the far
northwest panhandles closer to the core of the upper low. Deep layer
shear will be somewhat weaker today...but still sufficient when
combined with moderate instability to support some strong to severe
storms with large hail and damaging winds the main threats. No
organized or widespread heavy rain is expected today...but precipitable waters will
still remain supportive of some locally heavy downpours with the
storms...which could aggravate flooding problems but likely on a very
localized basis.

Low thunderstorm chances will continue on Memorial Day as another
shortwave trough pivots around the weakening upper low/trough. Timing
of this shortwave will likely place the slightly better thunderstorm
chances across the northeast panhandles...but hard to rule out an
isolated afternoon storm about anywhere. A few storms could again be
strong to severe...but weaker deep layer shear and instability should
preclude any organized severe weather risk.

Tuesday and Wednesday...weak middle-level perturbations continue to
ripple across the region within a still active southern stream. With
lingering moisture and instability still around...could see some
isolated convection both days...but nothing organized or widespread
is anticipated at this time.

It continues to look like the next chance for widespread thunderstorm
activity will come during the latter half of the week...starting
Wednesday night or the next upper trough approaches
from the west. Highest chances at this point look to be Wednesday
night or Thursday into Friday/Friday night...with possibly a drying
trend by the weekend as this trough looks to remain open and more
progressive than the last few.


several rivers mainly across the eastern half of the panhandles will
continue to run at bankfull levels today. They have all dropped below
flood stage...and despite the potential for some secondary
crests...are expected to remain below flood stage. Any thunderstorm
activity the next few days will be of a much more isolated to
scattered nature. This could lead to some localized rises or aggravate
flooding issues on a localized basis...but no widespread heavy rains
or flooding issues are anticipated for at least the next several



Ama watches/warnings/advisories...




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