Area Forecast Discussion
Issued by NWS North Platte, NE
FXUS63 KLBF 282330 AAA
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
630 PM CDT SUN AUG 28 2016
.SHORT TERM...(This evening through Monday)
Issued at 349 PM CDT Sun Aug 28 2016
An upper level low pressure system currently centered very near
the four corners, will track east and weaken tonight into Monday.
Models have been keeping the majority of the precipitation
associated with this system to the south of the area tonight into
Monday. Will maintain however a slight chance for showers and
thunderstorms within a weak deformation zone area that sets up
later tonight into Monday across the eastern through southern
portions of the forecast area. Otherwise an increase in mid and
high level cloudiness is expected tonight with a partly sunny day
Monday. This will have a minimal impact on high temperatures
Monday across the southeast portions of the area, where mid 80s
are generally expected. North and western areas will see upper 80s
to lower 90s where there will be less cloud cover.
.LONG TERM...(Monday night through Sunday)
Issued at 349 PM CDT Sun Aug 28 2016
Monday night through Wednesday...the upper low across Arizona is
moving very slowly east today. The models lift the low into the
Central Plains Monday and open it up at the same time producing a
disorganized area of showers and thunderstorms across Srn and Cntl
Neb. The forecast uses a blend of the NAM12...GFS and ECM models.
The NAM12 was the farthest north with system and the most
aggressive. If that model verifies...deep easterlies develop and
winds at the sfc actually become east northeast for a time as the
system deepens across Swrn Neb. The model consensus shows the
development of a shear axis forced by separate High pressure systems
across the Rockies and the Midsouth. This would produce a more
narrowly focused area of showers and thunderstorms affecting parts
of Northern KS and South and Cntl Neb. Pops are limited to 30 to 40
percent across Srn Neb affecting areas mostly south of interstate 80
including Custer County.
The temperature forecast uses a blend of guidance plus bias
correction for highs in the upper 70s to around 80 south...low to
mid 80s north. This is a solid reflection of the amount of cloud
cover the models are forecasting. Lows fall into the upper 50s to
The models continue to show dew points in the 50s to mid 60s. The
ARW...SREF and NAM12 models show fog forming Tuesday morning. The
NAM12 and SREF show fog forming Wednesday morning also...which is
beyond the range of the ARW which is a 48-hour forecast. The
forecast is for areas of fog Tuesday morning and the forecast for
fog Wednesday morning will wait on the performance of the model
forecast Tuesday morning.
Wednesday night through Sunday...rain chances subside Wednesday and
backdoor high pressure builds into the upper Midwest Thursday. Once
again...the models have cooled the temperature forecast as a result
of this high pressure building south from Canada. Thus highs
Thursday will probably continue in the lower 80s and warm into the
mid to upper 80s Friday through Sunday. This is a result of low
pressure reforming on the Northern High plains and drawing warm air
off the high plains.
South winds would continue through Sunday. The ECM maintains south
flow through day-10 as a result of a blocking ridge in the North
Pacific. Dew points would remain in the 50s to mid 60s with the
south winds. The ECM and GFS low cloud procedure gives a definite
signal for morning stratus and perhaps fog. This would also help
keep down down with a later start to solar heating.
Winds aloft at 300 mb increase Friday and beyond. This is
the result of an upper level trof dropping through the Pacific
Northwest. The forecast is for chance pops Saturday night and
Sunday. The multi parameter severe weather ensemble procedure
suggests a modest chance for severe storms but nothing definitive.
The better forcing is across the Dakotas and Upper Midwest.
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 624 PM CDT Sun Aug 28 2016
Increasing mid and high clouds expected over mainly southwest
Nebraska tonight with scattered mid and high clouds over northern
Nebraska. Some scattered thunderstorm activity over northeast
Colorado and the southern Nebraska Panhandle shold stay out of
western Nebraska over night. Winds will become light and variable
this evening and will pick up out of the south around 10kts Monday
morning late. Some thunderstorms are possible over southwest
Nebraska from KIML to KLBF Monday afternoon but do not have strong
confidence and have left out of KLBF taf.