Area Forecast Discussion
Issued by NWS Goodland, KS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KGLD 191717

Area Forecast Discussion
National Weather Service Goodland KS
1117 AM MDT Wed Apr 19 2017

.SHORT TERM...(Today through Friday night)
Issued at 306 AM MDT Wed Apr 19 2017

Forecast issues will be chances of precipitation through the period.
Satellite showing an amplified and blocky flow over the Pacific into
western North America which then transitions to a progressive flow
over the rest of the country. A rather strong shortwave was moving
across Wyoming.

At jet level...models were close with the Nam and Canadian doing a
little better than the rest. At mid levels...the Canadian and Nam
were also doing a little here as well. The Nam and Rap were doing
well at the surface. Models started out slightly cool on the low
level thermal field but were not too bad.

Today/tonight...An area of stratus and fog has developed to the
north of the front and surface low. So kept or only adjusted
slightly what the previous shifts left for me. Models still showing
some cape and even some light qpf. However there does not look like
a lot of moisture around and neighbors are not going for anything.
However I still would not be surprised if virga or sprinkles took
place. Temperatures will warm with more sun and warmer 850 mb
temperatures so adjusted high temperatures up a little.

Left front quadrant looks to move just north of the area early
today. Jet axis starts out over the northern portion of the area
early in the night. The right rear quadrant moves over and affects
the southeast half of the area during the last half of the night.
Shortwave trough also moves through during the night with adequate
theta-e lapse rates. So have put a slight chance of showers in the
last half of the night.

Thursday/Thursday night...Right rear quadrant remains over the
northern portion of the area during the morning before moving away.
Shortwave ridging during the day will keep it dry. Northerly winds
and cooler air moving will make for cooler temperatures over today.
The ridge moves east during the night as incoming system approaches
from the west. A shortwave trough, negatively tilted, along with a
mid level warm air advection pattern rotates into the area from late
in the evening into the overnight hours.

Based on the above, the builder pops look good and did not make any
changes. There appears to be elevated cape in the column along with
negative theta-e lapse rates in the southwest half. So added
isolated thunderstorms to the rain showers in that area.

Friday/Friday night...There are still some model differences in the
evolution and position of the incoming upper low. The Nam cuts off
the low further north. The latest Ecmwf and Gfs are in good
agreement in developing/moving the low from southeast Colorado and
southwest Kansas during the morning and then moving it into south
central Kansas in the afternoon. The Canadian does the same thing as
the Ecmwf and Gfs except does it slower.

The last two runs of the Gfs are almost identical. The latest Ecmwf
is very close to the 12z run and is just a little further south. The
Gefs mean and a vast majority of the members support the Gfs and
Ecmwf. Considering the ridging in advance of system and behind along
with the strong jet behind the trough definitely fits in with this
scenario. So the day looks wet.

So as a result, I nudged up pops up a little bit. Also there looks
to still be elevated cape in the column and so inserted embedded
thunderstorms. For the day, I also nudged high temperatures down a
little in the southwest half where cloud cover and precipitation
will keep temperatures a little cooler than what the builder gave

Precipitation should gradually decrease during the night as the
system moves east. Temperatures will get cold enough in the far west
that the rain and snow will mix for a short time.

.LONG TERM...(Saturday through Wednesday)
Issued at 210 AM MDT Wed Apr 19 2017

At the start of the extended period the models are showing northwest
flow aloft while ridging builds over the High Plains region. This
will produce dry conditions for most of the weekend over our CWA.
Another disturbance looks to track across the Dakotas and towards
the Great Lakes on Monday and Tuesday. However; only the tail end of
the front associated with this system looks to pass over our local
area. So at this time I see no impact to the region other than maybe
some strong winds.

The next big system to impact the region looks to make its
appearance on Tuesday night and Wednesday. As this system looks to
have similarity to last Friday`s system. As an upper level trough
over the Pacific Northwest dives southeast towards Colorado then.
This looks to produce another round of much needed precipitation on


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1114 AM MDT Wed Apr 19 2017

Wraparound cloudiness behind the front may impact KMCK with MVFR
ceilings for a couple of hours early this afternoon, then becoming
VFR as the cloudiness dissipates.

Scattered high based virga/showers may develop across the region
this afternoon with daytime heating and cold air aloft, but are
not expected to impact operations.

Northerly surface winds will continue to gust to 20-30kts behind
the cold front that moved through this morning, diminishing after




AVIATION...024 is the U.S. government's official web portal to all federal, state and local government web resources and services.