053
FXUS63 KLBF 122342
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
642 PM CDT Sun May 12 2024

.KEY MESSAGES...

- Three storm systems will cross the cntl/nrn Plains during the
  next 7 days- One tonight and Monday, then Tuesday night and
  Wednesday followed a third Thursday night and Friday.

- The risk of anything more than an isolated strong or severe
  thunderstorm during the next 7 days is low at this time.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 318 PM CDT Sun May 12 2024

The area of deformation and rain operating across scntl and
swrn Nebraska this afternoon should shift south and east as the
upper low across Colo moves east into KS tonight. The rain
forecast uses the short term model blend plus the NAM and HREF.

Rain processes have been top-down and this suggests lapse rates have
moistened up. Nonetheless, isolated thunderstorms are underway
across the Sandhills and south of Interstate 80. The forecast
continues isolated thunderstorm chances overnight. The thunderstorms
are mainly for the early evening hours as suggested by the HRRR
echo tops product. A warm sector has opened up across the
Sandhills, ncntl and swrn Nebraska this afternoon supporting
instability. Sfc obs show this underway and an approaching cold
front from the north supports thunderstorms this evening.

All of this rain should be south and east of the area by mid morning
Monday. Drier air will move in aloft for partly cloudy skies. The
temperature forecast Monday uses the short term model blend plus the
NBM 50th. Wrn/ncntl Nebraska will be under a WAA zone Monday
afternoon and this will support highs in the mid 70s.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 318 PM CDT Sun May 12 2024

The next item of interest is the prospect of showers and thunderstorms
Tuesday afternoon and Tuesday night. The models show an upper
level disturbance off the coast of British Columbia moving east
through the nrn Plains during this time. Only the NAM and GEMreg
models show storms developing across ncntl Nebraska Tuesday
afternoon. The concern is winds aloft at h500mb will be strong,
30-45kt, K-indices well in the 30s to near 40 and perhaps 1500
J/KG of MLCAPE will be in place. The models are in good
agreement showing this disturbance off of BC moving through the
Dakotas during the afternoon for upper level support. All of
this could support an isolated strong or severe thunderstorm
chance across ncntl Nebraska.

Additional shower and thunderstorm chance is in place for a
cold front moving through Tuesday night with rain chances
lasting into Wednesday.

A storm system south of the Aleutians will track south and
east, perhaps crossing the nrn Plains Thursday or Friday,
according to the ECM. The GFS tracks the system through the
central provinces of Canada. The forecast is for isolated
thunderstorms with this system but it`s worth noting the ECM
with it`s srn storm track suggests significant post-frontal
convection Friday night.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 641 PM CDT Sun May 12 2024

Isolated showers and thunderstorms will continue to impact the
Sandhills and into southwest Nebraska through the evening. Small
hail, wind gusts up to 40 mph and briefly heavy rainfall will cause
some minor aviation concerns as visibility restrictions are also
possible. Showers will diminish during the wee hours of Monday
morning with VFR conditions returning to the region through the
afternoon.

&&

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

&&

$$

SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Kulik