Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 092327
Area Forecast Discussion
National Weather Service Goodland KS
427 PM MST Fri Dec 9 2016
.SHORT TERM...(This evening through Saturday)
Issued at 159 PM MST Fri Dec 9 2016
Main forecast concerns will be fog coverage through tomorrow morning
and high temperatures tomorrow. Fast west to northwest flow aloft
continues across the area. At the surface, arctic high pressure has
pushed off to the east as a strengthening lee trough has developed
to our west. This has tightened the pressure gradient allowing
southerly winds to increase low level moisture over the western
portion of the area, especially over the snow field.
Models having a little difficulty in the handling of the low level
moisture and cloud fields today. The Nam tends to be overdone and
the Gfs is too dry and does not have enough cloud cover. The Sref
seems to have the best handle. High resolution guidance, including
the Nam, brings in stratus once again tonight with the main question
of how much if any fog.
The Nam does have a bad habit of overdoing fog in this scenario. It
did get the stratus right from yesterday. However because of the
increase of low level moisture already in the west and the other
high resolution guidance showing fog developing during the night in
the same place as the current higher dewpoints, although some models
develop the fog faster than others, believe some mention of fog is
warranted. Even though the models differ on timing of fog
development they do agree on the area. So was confident enough to
add patchy fog, freezing due to much below 32 degree temperatures,
for along and east of the Colorado border from late this evening
into tomorrow morning.
The next question will be how fast does the cloud cover decrease.
Some cloud cover does hang on into the afternoon the east and
northeast portions of the area. At this time went with a blend with
the warmest temperatures along and west of the Colorado border and
the coolest in the far northern and eastern sections. However am
uncertain on this.
.LONG TERM...(Saturday night through Friday)
Issued at 212 PM MST Fri Dec 9 2016
Generally west to northwesterly flow aloft prevails during the long
term period, with a few chances for precipitation as disturbances
pass over the region. Temperatures are more seasonal to start the
period before another blast of arctic air moves into the area.
A shortwave moves across the High Plains Saturday night, sending a
cold front through the region. This disturbance generates a slight
chance of light snow along the Nebraska border early Sunday before
moving out. Currently, no snow accumulation is expected with limited
Dry conditions return by Sunday night and carry on into Monday, with
temperatures rising slightly on Monday ahead of the next system. A
stronger cold front traverses the area Monday night into Tuesday,
bringing a blast of colder air.
Light snow will be possible Tuesday night into Wednesday following
the front as strong high pressure comes down towards the High Plains
and a shortwave moves passed Colorado. This appears to be the best
chance for precipitation during the long term, but would not put too
much stock into it until further down the line. Nearly zonal flow
continues on Thursday.
An upper trough travels from the west coast to the Plains towards
the end of the week, creating additional chances for snow. Will see
how discrepancies with the location and timing of this trough are
resolved in the coming days.
High temperatures trend up into the 40s for Monday. This is followed
by a dip, with highs in the 20s and 30s the rest of the work week.
Lows drop from the 20s Saturday night to the single digits for
Tuesday and Wednesday nights. Will need to monitor how cold
guidance trends with this airmass.
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 427 PM MST Fri Dec 9 2016
For KGLD...VFR conditions with scattered low/mid clouds thru 10z
Saturday. From 10z-15z Saturday...MVFR conditions with ceilings
down to BKN020 and visibility in fog to 3sm. Aft 15z Saturday...
VFR w/ mainly scattered high clouds. Winds SSW around 10kts.
For KMCK...VFR conditions with BKN045 thru 10z Saturday. 10z-17z
Saturday 3-6sm in fog at times with ceilings ranging from
OVC015-025. Aft 17z Saturday...MVFR w/ ceilings BKN030. Winds LGT/VAR
thru 10z Saturday...becoming E around 10kts thru 14z Saturday.
From 14z Saturday onward...ESE around 10kts.