182
FXUS63 KLBF 041759
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1259 PM CDT Tue Jun 4 2024

.KEY MESSAGES...

-  Ongoing showers and thunderstorms exit the area later this
   morning, with dry conditions then expected to prevail for
   Wednesday and Thursday.

-  Persistent shower and thunderstorm chances return for Friday
   and into early next week, with the threat for severe weather
   uncertain.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 401 AM CDT Tue Jun 4 2024

Currently, showers and thunderstorms persist for much of western and
north central Nebraska, with the greatest coverage currently east of
HWY 83. This convection is occurring in the wake of a quick
moving outflow boundary, which is currently dropping through
central Nebraska. A cold front is moving eastward through the
Panhandle, with temperatures in the middle to upper 60s ahead of
the front across the area.

For the rest of this morning, expect scattered shower and
thunderstorm chances to persist ahead of the encroaching cold
frontal boundary. Convection has largely remained rather benign this
morning, though at least a couple instances of wind gusts in excess
of 45 miles per hour have been observed this evening (one of which
being a heat burst at KIML). These general thunderstorms are
expected to persist for a few more hours this morning, before the
cold front pushes through the are and ends the threat from west to
east. Local rainfall amounts exceeding 0.50" will be possible
through late this morning. Aloft, an upper level low currently
positioned across northern MT/southern Saskatchewan will continue to
push east today, with a trough axis moving overhead late this
morning. Behind this trough axis, heights rise quickly, with
subsidence increasing aloft. This will lead to gradually clearing
skies this afternoon from west to east. A combination of mechanical
mixing (as cold advection increases behind the cold front) and
eventually diurnal mixing should lead to strengthening northwest
winds late this morning, as higher momentum flow is mixed downwards.
H7-H85 flow of 25-35kts will promote surface wind gusts of 30-35mph
through early this afternoon, with winds then weakening into this
evening. Temperatures range from the middle 70s across northern
Nebraska to the low/mid-80s south of I-80 this afternoon.

For Wednesday, upper ridging begins to amplify across the western
CONUS, with the high pressure center anchored over the Four Corners.
Height rises persist across the area, and H5 heights look to
approach and exceed the 90th percentile climo by Wednesday night.
This, combined with increasing low level warm advection, will send
highs back into the 80s for northern Nebraska, and into the lower
90s for areas south of I-80 tomorrow afternoon. By late tomorrow
afternoon, a weak surface low will push across the SD/NE border,
with a weak surface front pushing through the area. This will advect
drier air into the area in its wake, and will help temper to temper
any heat concerns tomorrow. Lows tomorrow night fall into the upper
40s to 50s, with the drier air in place and winds weakening as
surface ridging spills into the area.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 401 AM CDT Tue Jun 4 2024

The area remains under the influence of the upper ridge again on
Thursday, though highs will be cooler in the lower 80s in the wake
of Wednesday`s cool front. By Friday, increasing southerly flow on
the backside of the departing surface high will lead to increasing
moisture return, with a narrow corridor of upper 50 to perhaps low
60 dewpoints advecting across western Nebraska. As instability
increases during the afternoon, convection is expected to develop
across the high terrain of WY/CO. This could move eastward into
western Nebraska with time, with at least some threat for strong to
severe thunderstorms. Discrepancies remain in ensemble/deterministic
guidance with respect to the positioning of the moist axis (and
associated instability), and leads to low confidence with respect to
where convection will track. This will need to be monitored, as a
return of strong to severe thunderstorms will be possible for
western Nebraska Friday evening.

The threat for thunderstorms looks to persist into this weekend and
early next week, with the area remaining in the broad northwesterly
flow regime aloft. Additional weaker frontal boundaries will likely
drive the degree of any severe weather threat each day, and
confidence remains low for now. By Monday, a stronger front will
drop into the area, in association with a surface low dropping
southward across the Great Lakes. Ensemble guidance continues to
point towards elevated (40-60% of >0.1") probabilities of more
widespread precipitation in association with this boundary, and this
looks to be the next shot at precipitation coverage higher than just
scattered thunderstorms. Lesser precipitation chances could exist in
the wake of this stronger front, with at least some guidance pushing
this front to near the Gulf Coast through Tuesday. This would leave
much drier air in place across western and north central Nebraska,
limiting chances for showers and thunderstorms.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1258 PM CDT Tue Jun 4 2024

VFR conditions are expected through the forecast period.

Lingering mid-level clouds will clear west to east through this
afternoon, leaving clear to mostly clear skies overnight into
Wednesday. Winds will gradually wane this evening, veering as
they do and becoming southwesterly by Wednesday morning when
gusts may again approach 20 knots.

&&

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

&&

$$

SHORT TERM...Brown
LONG TERM...Brown
AVIATION...NMJ