-- Discussion containing changed information from previous version are highlighted. --
818
FXUS63 KOAX 201654
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1154 AM CDT Thu Jun 20 2024

.KEY MESSAGES...

- Rain chances continue through Saturday and then return to the
  forecast Tuesday and Tuesday night. Isolated occurrences of
  severe weather and/or flooding are possible, especially
  across portions of northeast NE and west-central IA.

- Gradually warming temperatures through the weekend into early
  next week. Heat indices approaching 100 to 105 on Monday and
  Tuesday.

&&

.DISCUSSION...
Issued at 410 AM CDT Thu Jun 20 2024

Widespread temps in the 60s this morning aren`t all that far off
of the high temps set earlier today. Omaha`s high of 75 was the
coolest high of the month so far under the influence of CAA sky
that averaged 90% cloud cover.

The front stalled just south of Falls City / Des Moines / Topeka
pushes north over the next 24 hours due in part to the ridging
in the eastern US expanding west and increasing heights across
Iowa and Nebraska. Southerly surface flow helps produce some
WAA. Even then, the front isn`t done with us as it crash south
again this weekend.


.TODAY...

Currently a few scattered thundershowers are bookending the
area. The first batch are along the front draped across
northern Kansas, through far northwest Missouri, clipping Page
County in far southwest Iowa. Falls City, NE has recorded a
trace of precip in the past hour. 280 miles north, spotty
convection has dropped some showers over Cedar and Knox counties
along the SD state line. This area of convection is associated
with diffluent flow at 500 hPa and the nose of a nocturnal LLJ -
a common feature during June in the Great Plains. The
precipitation will grow in coverage and intensity as a mid-
level wave works in from the west over the course of the day.
The majority of QPF will be falling on the northern side of the
Missouri River in SoDak, but chance PoPs seem warranted in the
northern tier of Nebraskan counties. HREF chances for 2" of rain
in 24 hours is about 40% in northeast Nebraska and double that
north of SD`s I-90. Chances for 2" will be under 20%. But were
that precip to be realized on this side of the river, flash
flooding could result.

PoPs (40%) peak around noon and again around midnight as the
remnants of a prospective MCS pushes west to east along or just
north of the NE/SD state line.

.FRIDAY...

More precip is possible along the front still progged to be
lying near the SD border on Friday in a near repeat of
Thursday`s convection. Most will fall in SoDak with chances
growing late Friday night as a deterministic models whip up
another MCS working through the Sand Hills.

High temps on Friday will crest near 90F; a 5F (south) to 15F
(north) boost from Thursday`s expectations.

.Saturday...

A shortwave trof will drag the pesky and tenacious front *back*
through the area, this time acting as a cold front. Best diurnal
instability will occur in far southeast Nebraska and southwest
Iowa due to the front`s timing which will pass through Omaha
and the Lincoln metros early in the afternoon.

.SUNDAY AND EARLY NEXT WEEK...

A break in precip for Sunday and Monday can be attributed to the
transient shortwave ridge. Sunday`s highs will mostly be relegated
to the upper 80s with mid-90s on tap for Monday afternoon.
Tuesday will bring a cold front, but not before temps soar once
again. Both Monday and Tuesday bring heat concerns with forecast
heat indices reaching 105 in spots. The cold front may bring an
opportunity for strong to severe thunderstorms and heavy rain.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
-- Changed Discussion --
Issued at 1154 AM CDT Thu Jun 20 2024

MVFR to IFR ceilings are expected to gradually improve to VFR
this afternoon with only passing mid clouds by late this evening
overnight. Ongoing showers and storms are expected to remain
north of the TAF sites with any additional development most
likely doing the same, but can`t completely rule out a stray
shower or storm hitting a site this afternoon/early this
evening. Otherwise, winds will be southeasterly to southerly at
or below 10 kts.
-- End Changed Discussion --

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.

&&

$$

DISCUSSION...Nicolaisen
AVIATION...CA