217
FXUS63 KBIS 052046
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
346 PM CDT Sun May 5 2024

.KEY MESSAGES...

- Southeast winds gusting to 50 mph continue over western and
  south central North Dakota into late tonight. Thereafter,
  focus for higher winds Monday shifts east including all of
  central North Dakota including the James River Valley.

- Widespread showers and isolated to scattered thunderstorms
  are expected late tonight through Tuesday, especially in far
  western North Dakota.

- There is a conditional risk of strong thunderstorms Monday
  afternoon, mainly across southern parts of the state.

- Focus for stronger winds shifts to southwest North Dakota for
  Tuesday, after winds shift westerly.

&&

.DISCUSSION...
Issued at 221 PM CDT Sun May 5 2024

Current surface analysis places low over the Northern and
Central Rockies, with broad high over the Midwest. This is
resulting in a tight pressure gradient through the Central into
the Northern Plains. Upper level analysis places ridging over
the Northern Plains ahead of low that is now pushing through
Great Basin. Over our neck of the woods, gusty southeast winds
continue in the tight pressure gradient, especially over western
into south central North Dakota. Strongest winds now focused
over southwest North Dakota where some gusts around 50 mph have
been noted.

For tonight, upper low passes over the Rockies with surface low
pushing to the lee side of the Rockies into the plains of
Montana/Eastern Wyoming. In the meantime, a low level jet will
also be intensifying. Gusty southeast winds therefore will
continue through the evening into the overnight given the
gradient and possible enhancement from the jet, but will start
to ease up over western North Dakota after midnight, while
continuing over portions of central North Dakota. In the
meantime, rain shower chances will gradually be on the increase
with the upper low continuing its approach.

On Monday, upper low becomes influenced by a low to the
northwest and becomes negatively tilted as it works into the
Northern Plains, but still remains closed. Chances for
showers/storms will continue to spread across the area, with the
highest chances remaining to the west. There remains some
concern for severe potential over southern portions of the area,
with the potential remaining rather consistent per multiple
runs of the CSU machine learning probabilities. Forcing will be
ample giving the lifting boundary, and 0-6KM deep layer shear
will be more than ample at ~40-60kts, just instability remains
in question. The next issue is winds, with the focus for gusty
southeast winds shifting more into central/eastern North Dakota
with the surface low lifting into the far western
Dakotas/eastern Montana. Pressure gradient remains rather tight,
so expect another round of gusts to 50 mph.

As we get into the overnight into Tuesday, low lifts northeast
well into the Northern Plains and loiters over the region. Still
some question on the exact implications of the dry slot and how
far west it will go. Speaking of Tuesday, northwest winds
become a possible concern over the southwest, but again the
intensity of the winds depend on how far north the surface low
lifts.

Precipitation chances remain through Wednesday and possibly
into Thursday pending the departure of the low from the region.
Seasonably mild temperatures expected.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1250 PM CDT Sun May 5 2024

Gusty southeast winds are expected to continue over most
locations through the forecast period. VFR conditions will
prevail until late tonight as periods of rain start to move into
the area from west to east. Ceilings will drop to MVFR to IFR
levels Monday morning.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 4 AM CDT /3 AM MDT/ Monday for NDZ001-002-
009-010-017-018-031>033-040-041-043-044.
Wind Advisory from 6 AM Monday to midnight CDT Monday night
for NDZ003>005-011>013-022-023-025-037-048-051.
Wind Advisory until midnight CDT /11 PM MDT/ Monday night for
NDZ019-020-034-042-045.
Wind Advisory until midnight CDT Monday night for NDZ021-035-
036-046-047-050.

&&

$$

DISCUSSION...JJS
AVIATION...JJS