Area Forecast Discussion
Issued by NWS Goodland, KS
FXUS63 KGLD 192105
Area Forecast Discussion
National Weather Service Goodland KS
305 PM MDT Wed Oct 19 2016
.SHORT TERM...(This evening through Thursday)
Issued at 245 PM MDT Wed Oct 19 2016
Latest upper level analysis shows a long wave trough over the
central CONUS. Within the trough are a few smaller scale
features. One of these short wave troughs was moving into Central
Nebraska. Ahead of it scattered rainshowers with some lightning
were seen on radar. Another trough was moving into Nebraska from
the west. Ahead of this trough showers were beginning to develop
due to the steep lapse rates up to 600mb and the low level
moisture moving in from the northwest.
For the rest of the afternoon and the evening foresee the area of
developing showers to continue east across the northern 1/3 or so
of the Tri- State Area. Meanwhile the other area of showers that
has been moving across the Tri-State Area will exit by early
Tonight the Tri-State Area should be rain free by midnight or
earlier. Overnight frost will develop for counties along the KS/CO
border. Frost development is expected in the counties just east of
the advisory, however the greatest areal extent of frost and the
coolest temperatures will be in the advisory area. Low lying
locations in East Central Colorado may have a hard freeze. A weak
cold front will move through beginning in the overnight hours.
Thursday morning the weak front will move through the rest of the
Tri-State Area. During the afternoon a surface high will move
through causing the winds to be light and turn back to the south.
.LONG TERM...(Thursday night through Wednesday)
Issued at 123 PM MDT Wed Oct 19 2016
A weak short wave trough moves through the apex of the initial
upper ridge that moves east of the Rockies and across the high
plains Thursday night and early Friday. The subsequent broad major
ridge axis moves past the Rockies and over the Plains States on
Friday and Friday night with another weak upper short wave trough
moving through the apex of the ridge on Saturday. The weak short
wave trough moves east with the ridge reamplifying over the
Rockies and High Plains Sunday through early Monday. The whole
pattern gets shifted east as a low pressure area dives south into
position off the Pacific Northwest by Tuesday morning with
southwest flow aloft and weak embedded short waves lifting out
across the Central High Plains region Monday and Tuesday.
The forecast area appears to remain mostly dry and warmer than
average through the extended period. High Temperatures should be
well into the 70s with lows mostly in the upper 30s to the upper
40s. The exception is the precipitation possible Tuesday night as
the upper short wave trough lifts out across the forecast area.
The issue that far out is the ECMWF and GFS have solutions that
become increasingly divergent between Tuesday and Wednesday. The
ECMWF strengthens the initial trough more than the GFS while the
GFS latches on to the second trough more and deepens it further
than the ECMWF over the southwestern U.S.
Do not have enough confidence in either model scenario at this
time to vary from the Superblend solution of producing isolated
to chance POPS with light QPF across portions of the GLD forecast
area during the Tuesday night time frame.
One upcoming coordination issue may be the possibility of frost
across portions of the forecast area on Thursday night/early
Friday morning. Skies are expected to be initially clear, but low
temperatures may be affected by increasing clouds. Am not
confident at all in issuing a frost/freeze highlight for that
period at this time. Also have a possible frost/freeze highlight
for tonight/early Thursday morning and don`t want to confuse the
issue at this point.
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1059 AM MDT Wed Oct 19 2016
VFR conditions expected for the TAFs. Clouds will clear by late
afternoon then return tonight as the corridor of clouds over
southern Wyoming moves over the TAF sites. Winds will shift from
the north to northwest as the clouds return tonight.
KS...Frost Advisory from 2 AM MDT /3 AM CDT/ to 9 AM MDT /10 AM CDT/
Thursday for KSZ001-013-027-041.
CO...Frost Advisory from 2 AM to 9 AM MDT Thursday for COZ090>092.
NE...Frost Advisory from 2 AM to 9 AM MDT Thursday for NEZ079.