Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 280818
Area Forecast Discussion
National Weather Service Goodland KS
218 AM MDT WED SEP 28 2016
.SHORT TERM...(Today through Friday night)
Issued at 216 AM MDT Wed Sep 28 2016
Forecast issues will be temperatures and if there will be a chance
of precipitation at the end of this period. Satellite showing an
amplified flow from the Pacific into eastern North America. Flow
over the country is being dominated by large/slow moving upper low
that is centered near the Great Lakes.
A cold front is located over northeast Nebraska. The Canadian and
Gfs were doing a little better at the mid levels to start out. The
Sref was doing a little better on the surface. The Canadian and Gfs
were starting out best on the low level thermal field.
For today/tonight...Strengthening mid/upper level ridge and dry air
will be in place. As a result, the initial and only detail on how
warm it will get will be how fast the above mentioned cold front
move in from the northeast. All models are pretty consistent in
bringing the wind shift/cooler air from northeast to southwest.
Guidance is showing cooler temperatures east and warmer west which
makes sense and went close to.
Very light wind field in place, especially over the eastern third.
Cooled off the lows a little from the previous forecast as a result
For Thursday/Thursday night...Pressure gradient and 3 hour pressure
falls increase during the day, especially over the western half. So
should see near breezy to breezy conditions in the western half.
Still should have plenty of sun due to strong ridging aloft and dry
air. The combination of a cool start and upslope/return flow winds
bringing recycled cool air, will make for temperatures 5 to 8
degrees cooler than todays. Will be another cool night but should be
a little warmer due to more wind.
For Friday/Friday night...New model data is consistent in position
of the eastern conus low. Not only is it slow to move east it
actually starts moving it back slowly to the northwest. Comparing
current model run to the previous run, the models are all consistent
in a slower/further west solution. This makes sense since there are
strong ridges on either side of the system, the same jet wind speeds
on either side of it, and there is no kicker to move it. The affect
of this will be to keep higher heights/stronger ridging aloft over
As a result, the air mass remains drier with what mid level lift
there is still out to the west of the area. Deterministic qpf and
Gefs ensemble qpf output also keep the chance of measurable out to
the west of our area. So will keep this period dry for now.
Models are a little warmer this day than Thursday. Am a little leary
of this since system to the east is slow to move and expect little
warm air advection with light upslope winds. Since most guidance
is consistent on this will use a blend for the high temperatures.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 127 PM MDT Tue Sep 27 2016
For this extended forecast period, the main concern will be a large-
scale pattern shift that is expected to take place across the
Continental United States. Early in the period (tomorrow night
through Friday), a large upper level low will be situated over the
eastern United States, a ridge of high pressure dominating the Great
Plains, and a weakening Rex Block over the western United States.
For Thursday and Friday, anticipate dry weather and seasonable
temperatures as a result of this Great Plains ridge.
The large-scale upper level pattern shift will take place this
weekend. The eastern US low lifts northeast into southeastern
Canada, the high pressure ridge weakens, and a large upper level
trough moves from the Pacific northwest toward the Rockies. As the
trough begins to influence the High Plains, there could be a few
isolated storms Saturday and Sunday. However, moisture and
instability appear quite low so this could easily amount to nothing
as the weak lead disturbances pass through.
The main upper level trough should move out across the Great Plains
next week; the exact day depends on which guidance member you
choose. As this disturbance passes through, showers and storms are
possible. In addition, a cold front should pass as well. Cooler
temperatures should be expected behind the front. Current
indications are that below freezing temperatures are unlikely but
this will be something to keep an eye on.
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1120 PM MDT Tue Sep 27 2016
VFR expected at both KGLD and KMCK through the TAF period. High
pressure aloft will result in clear skies and light winds.