Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 232106
Area Forecast Discussion
National Weather Service Goodland KS
206 PM MST Mon Jan 23 2017
.SHORT TERM...(Today through Wednesday)
Issued at 318 AM MST Mon Jan 23 2017
Upper ridging will persist through today ahead of an approaching
shortwave trough. Surface low will develop over northeast Colorado
associated with the upper wave, with a warm front extending into
northwest Kansas. Breezy southwest winds south of the front will
aid in downslope warming where afternoon temperatures will
reach the upper 50s to around 60. Upper wave will cut off tonight
over northeast Colorado with scattered rain and snow showers
developing late. The system will track across the Nebraska/Kansas
border area on Tuesday with much colder temperatures, scattered
rain and snow showers and windy conditions. Accumulations will be
light, less than an inch, mainly north of I70. Some light
wraparound snow showers or flurries will linger into Tuesday night
before ending, with winds gradually diminishing. Dry but cold
northwest flow is expected on Wednesday with highs in the low to
mid 30s and partly sunny skies.
.LONG TERM...(Tuesday night through Monday)
Issued at 204 PM MST Mon Jan 23 2017
Forecast concerns will be precipitation/wind at the beginning of
this period followed by temperatures. Satellite showing an
amplified pattern from the Pacific into North America. At jet
level...the Canadian and Ecmwf were doing a little bit better on
the strong jet near and to the southwest of the area. At mid
levels...models started out fine with only subtle differences.
Tuesday night...strong jet is to the east and south of the area.
The 00z Ecmwf and 12z Canadian continued to be the slowest and
furthest south of the upper low. The 12z Ecmwf however came in
further north closer to the the other output. The brunt of this
system should be felt outsider our area.
Even with the system track not in a favorable position to produce
significant precipitation, in this case snow, there is enough
moisture and lift with okay but not great theta-e lapse rates that I
cannot rule out some light precipitation occurring this period.
So stuck with the slight chance to low chance pops the builder
gave me and blended/serpiscd with my neighbors.
Incoming cold air and the winds will be the main issues for this
period. Gradient and downward motions will still be tight/rather
stronger during the night, especially in the first half. With that
and collaboration populated the wind grids with Consmos.
Wednesday/Wednesday night...Any precipitation should be done by the
beginning of this period so removed the slight chance pops from the
northeast portion of the area that the builder gave me. There is
still enough of a gradient along with some downward motion to keep
windy conditions going through most of the day. Temperatures will be
colder and what the forecast builder gave me looks reasonable and
did not change.
During the night the surface ridge moves in and the winds will drop
off. However models are indicating that there will be increasing mid
and high level cloud cover. I did trend temperatures down slightly
because of all this.
Thursday...Northwest winds continue but will be not as strong as the
day before. Some warming occurs and could not argue against what the
blender gave me.
Thursday night through Monday...open wave in northerly flow aloft
moves through Thursday night into early Friday. After that, strong
ridging builds over the western portion of North America leaving the
area in northerly flow aloft. On Sunday this ridge is flattened and
pushed a little west as a shortwave trough moves into the north
central portion of the country on Monday.
It does look dry through the period, and that is reflected in what
the builder gave me. There looks to be a gradual warming trend
through the period. However will have to be careful that this
northerly flow will not sneak some colder air into the region.
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1035 AM MST Mon Jan 23 2017
VFR conditions will prevail through the first 12hr of the TAF
period, with decreasing confidence on prevailing conditions. After
06Z a cold front followed by light easterly flow may bring light
freezing drizzle, freezing fog, and low stratus to KMCK and
possibly KGLD. The timing/axis of main low level moisture push is
still uncertain and consensus of guidance does not support
prevailing lower conditions at this point. I was confident enough
in the pattern to introduce 6sm/3000ft to KMCK for the 10Z-14Z
period, but going forward we may need to introduce IFR/LIFR tempo
groups if consistency increases.
Gusty south winds at KGLD should decrease to 12kt or lower this
afternoon as low pressure shifts east and surface gradient
weakens. Winds will shift to the east-northeast then west at KMCK
through the TAF period as the cold front moves across the region,
and may shift to the west quicker at KGLD. Stronger winds will
develop at both KGLD and KMCK by the end the TAF period behind
this cold front.