327
FXUS63 KLBF 210905
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
405 AM CDT Sun Jul 21 2024

.KEY MESSAGES...

- Chances of showers and thunderstorms last through Monday
  night, with a low threat of severe weather. Afterwards, the
  chances for precipitation remain low for the remainder of the
  week.

- By mid week, the pattern sets up for a warmer and dryer
  pattern. With a return of warmer and dryer conditions fully
  setting in by late week, concerns for fire weather conditions
  may increase.

&&

.SYNOPSIS...
Issued at 402 AM CDT Sun Jul 21 2024

Upper air analysis and satellite imagery show an upper level
disturbance over central Iowa and a high amplitude ridge over the
western United States. The ridge extends into northern Alberta and
northern Saskatchewan. At the surface, high pressure is observed
over the Great Plains. On satellite, remnants of thunderstorms are
tracking south across the Dakotas this morning, and areas of fog are
observed developing over central Nebraska.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 402 AM CDT Sun Jul 21 2024

Through the early morning hours, the fog developing over central
Nebraska should continue to spread west. Patchy fog to areas of fog
will be possible across portions of north central Nebraska this
morning, mostly along and south of a line from O`Neill to Broken
Bow. The fog is expected to clear out around mid morning.

Through the rest of the afternoon, slight chances (20-30 percent) of
showers and thunderstorms persist across western and north central
Nebraska. Forcing appears relatively weak this afternoon, however
sufficient moisture will be available for a few quick thunderstorms.
The forcing for any potential storms this afternoon will be mainly
in the form of a PV anomaly with the upper level disturbance in Iowa
along with an embedded shortwave in the upper level flow. The
expected amounts of CAPE are quite low, generally less than 1000
J/kg, and shear is quite meager. At this time, have serious doubts
that any storms this afternoon would grow into any organized
convection.

Another round of showers and thunderstorms is expected again on
Monday. Another round of shortwaves progress through the upper level
flow, with suggestions of additional PV anomalies as the focus for
forcing. Much like Sunday, organized convection appears unlikely,
with mostly widespread and weak thunderstorms bringing some light
showers across western and north central Nebraska. Some of the more
aggressive CAMs hold storms together a bit longer, but the severe
threat continues to remain low.

Another concern in the short term is smoke and haze from fires
across the northern United States and Canada. The smoke was quite
apparent on satellite last evening, and the HRRR picks up the plume
quite nicely. Went ahead and added smoke and haze from the HRRR
model in the latest forecast. The near surface smoke is mostly
expected across portions of the Nebraska Panhandle, whereas the
vertically integrated plume (smoke aloft) is stronger over the
Sandhills and the Highway 83 corridor. Not expecting that this will
bring much impact on visibilities throughout the region, so much as
bring hazy skies through at least Monday afternoon.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 402 AM CDT Sun Jul 21 2024

As the week progresses, the upper level ridge is expected to
establish a bit more over portions of western Nebraska. As this
occurs, chances for precipitation become quite slim through the end
of the week. Along with the decreasing precipitation chances,
temperatures will begin to warm back up by late week. Spaghetti
plots are in fairly consistent agreement on a ridge breakdown
late week. Additionally, forecast soundings hint at inverted V
patterns and strong mixing of mid level winds to the surface.
With this being later in the week, it will certainly be worth
keeping a close eye on, as the combination of the warm, dry
pattern along with potential gusty winds could lead to increased
fire weather conditions.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 1145 PM CDT Sat Jul 20 2024

VFR conditions will prevail through the bulk of the forecast
period.

Overnight a few mid to high level clouds from convective debris
will traverse the area but otherwise a light wind and mainly SKC
will dominate. There is a small probability (10-30%) for fog to
work into the Platte River valley and possibly as far northwest
as KLBF, but confidence remains too low to include at this
point. Then, while isolated TSRA will develop through the
afternoon Sunday, the best organized threat for TSRA should
hold off until after 00Z Mon in the northern part of the state
and affecting KVTN.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Richie
SHORT TERM...Richie
LONG TERM...Richie
AVIATION...Stoppkotte