628
FXUS63 KUNR 140846
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
246 AM MDT Fri Jun 14 2024

.KEY MESSAGES...

- Chances for showers and thunderstorms through the weekend and
  into next week.

- Above normal temps continue through Saturday, cooling off moving
  into next week.

&&

.DISCUSSION...(Today Through Thursday)
Issued at 214 AM MDT Fri Jun 14 2024



Current surface analysis shows high pressure centered over the
Dakotas, with a surface low over south central Wyoming this
morning. Upper level models show upper ridge sliding over the
northern and central plains, while upper low sits over the
southwestern CONUS. Mostly clear skies this morning, with clouds
moving in from the southwest. Temperatures currently sit in the
mid 50s to mid 60s across the forecast area, with light and
variable winds. Ridging and associated high will allow for
another warm day today, with highs generally in the 80s.

As the high slides east of the forecast area, low level southerly
flow moves in, increasing theta-e and moisture through the day. Low
level jet also sets up over the region this morning, increasing
chances for showers/storms mainly over southwestern SD, then
spreading throughout the region as the day progresses. Models show
increasing CAPE to 1000-2000 j/Kg this afternoon, with the highest
CAPE values from northeastern WY into northwestern SD. As surface
low approaches, increasing cloud cover may hamper CAPE values for
some areas, however if storms are able to fire up, modest shear
(30-40kt) should be enough for supercell potential. Best chance
for severe will be in the afternoon and evening hours with large
hail and stronger winds being the main threats.

Saturday continues the above normal temperatures, with highs
climbing into the upper 80s to low 90s for much of the forecast
area. Daytime heating and some weak instability may allow for some
isolated showers/storms through the day, however better chance
comes later Saturday night into Sunday as a cold front pushes
through the region. Timing of the front may limit any severe
potential for Saturday, but boundary moving through will cool
things down for Sunday into early next week. Mostly dry conditions
through much of Sunday, however mid-level disturbance will
increase precipitation chances late Sunday into Monday and
potentially another disturbance affecting the region on Tuesday.
The latter half of next week, models show broad ridging build over
the central and eastern CONUS, which may push any disturbances to
our north, and bring warmer and drier conditions back into the
region.

&&

.AVIATION...(For the 06Z TAFS Through 06Z Friday Night)
Issued At 925 PM MDT Thu Jun 13 2024

Isolated showers and thunderstorms are possible mainly over
southwestern South Dakota after 06Z tonight, continuing through
Friday morning. Additional isolated storms are possible in the
afternoon.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...Dye
AVIATION...JC