Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 212012
Area Forecast Discussion
National Weather Service Goodland KS
212 PM MDT Fri Apr 21 2017
.SHORT TERM...(Today through Sunday tonight)
Issued at 407 AM MDT Fri Apr 21 2017
Main forecast issues will be current precipitation event, how cold
to make low temperatures Friday and Saturday nights, and the winds
on Sunday. Satellite showing an amplified flow that now extends from
the Pacific into North America. Incoming system is now
developing/digging into Colorado.
At jet level...models started out well and about the same with a
very slight advantage to the Nam. At mid levels...the models tended
to be too fast/far east with heights/features with the Nam and
Canadian doing the best. The Nam and Ecmwf were looked to be doing
the best with the surface pattern. The Nam and Canadian were doing a
little better than the Gfs and Sref with the low level thermal
Today/tonight...System is developing into Colorado as advertised by
yesterdays and tonights model output. A number of shortwave ahead of
the main system have and will move through the upper low arrives.
System slows down a little as it develops/moves across the area.
Models differ on position and speed with agreement worse than what
was shown 2 days ago.
However considering the position of low, mid level forcing, upslope
through 700 mb and favorable theta-e lapse rates, mainly southwest
half, most if not the entire area will receive measurable
precipitation with amounts decreasing further north and east.
Precipitation will be the most widespread from mid morning to mid
afternoon before starting a decreasing trend. Temperatures are
starting out a little warmer due to cloud cover and are pretty close
to expected maxes. However, there will not be much of a chance of
temperatures rising much.
Some subtle changes for tonight. Precipitation decreases through the
night as system moves off. However, now models start elongating the
trough and bring/rotate additional shortwave/mid level lift around
from the north. So precipitation will last longer in the west. There
looks to be a mix of rain and snow late. Also more cloud cover in
place do not expect temperatures to be able to drop as much.
Saturday/Saturday night...Jet axis and possible left front quadrants
will be near/over the southwest portion of the area through the
morning. Also because of elongated portion of the trough/shortwave
rotating through, precipitation will now last through the morning
with a mixture of rain and snow through mid morning. Right now do
not have any precipitation during the afternoon. However decently
cold air aloft could cause instability showers to develop. Day shift
will have to look into this.
Of concern is low and especially mid level cloud cover will last
longer/most of the day and that could impact temperatures especially
in the west. Did not make any changes to the temperatures and day
shift will need to take another look at this.
A little complex low temperature forecast. Winds will become light
over most of the area with little to no cloud cover. However surface
ridge moves through rather quickly with south to southwest winds
increasing after midnight. Winds looks to stay light the longest in
the east and that is where the coldest temperatures will be.
Currently do not have freezing temperatures but that could be
possible in the east. Frost should develop over most of the area
with the most frost in the east.
Sunday/Sunday night...cold temperatures/frost ends by mid morning.
Main stories for this day will much warmer temperatures, due to
ridging along and a much drier air mass in place, and the strong
southerly winds which may end up being more important. Very tight
pressure gradient and 3 hour pressure falls of 5 to 6 mb will make
for windy conditions. After consulting with neighbors have used
consmos to increase the wind speeds. At this time the relative
humidities look to stay just above 20 percent.
.LONG TERM...(Saturday night through Friday)
Issued at 212 PM MDT Fri Apr 21 2017
Dry weather starts out the long term period before the return of an
active pattern. Temperatures climb through Monday and decrease
Warming temperatures and dry conditions result from a ridge building
over the region Saturday night and Sunday. The combination of clear
skies, light winds, and temperatures bottoming out in the low/mid
30s leads to the potential for frost Saturday night into Sunday
morning. Winds do begin to strengthen in the morning which may
inhibit frost development, especially over the western portion of
the forecast area, but stay lighter further east.
Southerly winds peak in the afternoon as a lee trough develops along
the Rockies. Wind gusts of 30 to 40 mph are possible, making for a
windy day. Flow aloft turns zonal Sunday evening as the ridge
The next system travels across the northern Plains on Monday, with
most of its precipitation up in the Dakotas. However, there is a
chance some showers could develop as far south as locations north of
I-70 as the wave moves through and a cold front pushes south.
Another disturbance traverses the High Plains on Tuesday along with
a second blast of cooler air, dropping temperatures and generating
A stronger trough forms over the western CONUS on Wednesday and
pushes east onto the Plains through Friday, bringing the region a
better opportunity for precipitation. Rain showers and the
occasional chance for some thunder linger through the end of the
work week with this system. There are differences in the timing,
location, and strength of this feature, so will have to wait to
Temperatures climb from the low/mid 70s on Sunday to the 70s/low 80s
on Monday. Cooler air filters in and temperatures gradually decrease
into the upper 50s/low 60s by Thursday. With the exception of
Saturday night, lows are generally in the upper 30s and 40s.
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1119 AM MDT Fri Apr 21 2017
Rain showers continue to move across northwest Kansas and
southwest Nebraska. Moderate showers over NW Kansas have reduced
cigs to IFR and VIS 3-6 SM at KGLD this morning and this will
continue to be possible through the early afternoon. I couldn`t
rule out vis below 3sm, but this is more likely to be very
brief and not worth adding to TAF. MVFR conditions are more
likely at KMCK with lighter precip. Isolated thunderstorms can`t
be ruled out, but coverage is not worth vicinity mention at this
This activity should transition eastward and decrease in
intensity through 00Z, with precip possibly ending at KMCK first.
Both terminals should see VFR conditions by the mid evening hours.
There is a chance that lingering low level moisture near the
Colorado state line could support fog or stratus redevelopment
towards KGLD 09Z-14Z, but confidence is low that this would impact
the terminals (more likely over eastern Colorado). Winds should
shift from the southeast to the north as a front moves across the
region, with winds tonight and Saturday morning below 10kt.